Search

‘Arrayana’ mandarin is one of the most cultivated citrus species in Colombia, but this fruit has a short postharvest life and is sensitive to chilling injury (CI) during cold storage. Generating strategies that decrease CI to mandarin can reduce quantitative and qualitative losses postharvest. Brassinosteroids (BR) have been used as a sustainable technology to alleviate CI in fruits and improve postharvest quality. This study evaluated the effect of applying the 24-epibrasinolide analogue (EBR), at doses of 5 mg L−1; DI-31 analogue, at 5 and 10 mg L−1; and control, on the main physical and biochemical characteristics of ‘Arrayana’ mandarin stored at 4 °C for 40 days and, subsequently, 7 days at room temperature (shelf life). The application of EBR and DI-31 analogues reduced the appearance of CI in the exocarp of ‘Arrayana’ mandarin fruits by reducing electrolyte leakage, maintaining membrane integrity, and increasing antioxidant activity and phenol content at the end of cold storage and shelf life. This was especially pronounced with 5 mg L−1 of EBR. Similarly, the BR maintained the postharvest quality of mandarins by reducing weight loss, respiratory intensity, and chlorophyll degradation; increasing β-carotene; and maintaining titratable acidity and soluble solids. Our research reports, for the first time, CI tolerance in Arrayana mandarin using natural (EBR) and spirostanic (DI-31) analogues and illustrates the tolerance functionality of the DI-31 analogue on CI in the fruit postharvest.

Citrus fruit quality is defined as the combination of physical and chemical traits; some of which may change during the ripening phase, e.g., acidity and sugar content. A clear understanding of their genetic control would be very helpful for marker-assisted breeding programs especially with regard to the juvenile phase and some reproductive features that hamper the selection of improved hybrids. A genetic study was thus performed on the heredity of quality traits and QTL detection based on segregation in a progeny generated from a cross between clementine cv “Commun” (Citrus × reticulata cv clementine) and mandarin cv “Willow leaf” (C. reticulata Blanco). Parental and consensus genetic linkage maps were constructed using 645 SNP and SSR markers. These maps were represented by 10 linkage groups in clementine and 12 linkage groups in mandarin, representing 75% and 58% respectively of the previously published clementine reference map. A total of 16 traits, including fruit mass, equatorial diameter, juice percentage, total soluble solids, acidity, pH, glucose, fructose, sucrose, and citric and malic acid concentrations were evaluated at three maturation dates. High variations indicating transgressive segregation were found for all traits, with normal or close to normal distributions. QTL analysis performed using the multiple QTL model allowed the detection of 34 QTLs on the three maps. QTLs were distributed in different linkage groups and generally detected at only one date of the ripening phase. The percentage of total variation explained ranged from 12 to 37% per QTL. Major QTLs (R2 ≥ 30%) were detected for equatorial diameter, glucose, and fructose (expressed in percentage dry matter) on linkage groups 8 and 9. Co-localization of QTLs controlling correlated and uncorrelated traits were mainly found on linkage groups 2, 4, 8, and 9, particularly between fruit mass and acidity.

Fungal food spoilage plays a key role in the deterioration of food products, and finding a suitable natural preservative can solve this problem. Therefore, antifungal activity of green mandarin (Citrus reticulata) essential oil (GMEO) in the vapor phase against the growth of Penicillium (P.) expansum and P. chrysogenum inoculated on wheat bread (in situ experiment) was investigated in the current research. The volatile compounds of the GMEO were analyzed by a gas chromatograph coupled to a mass spectrometer (GC–MS), and its antioxidant activity was determined by testing free radical-scavenging capacity (DPPH assay). Moreover, the disc diffusion method was used to analyze the antifungal activity of GMEO in in vitro conditions. The results demonstrate that the Citrus reticulata EO consisted of α-limonene as the most abundant component (71.5%), followed by γ-terpinene (13.9%), and β-pinene (3.5%), and it displayed the weak antioxidant activity with the value of inhibition 5.6 ±0.7%, which corresponds to 103.0 ±6.4 µg TEAC.mL-1. The findings from the GMEO antifungal activity determination revealed that values for the inhibition zone with disc diffusion method ranged from 0.00 ±0.00 (no antifungal effectiveness) to 5.67 ±0.58 mm (moderate antifungal activity). Finally, exposure of Penicillium strains growing on bread to GMEO in vapor phase led to the finding that 250 μL.L-1 of GMEO exhibited the lowest value for mycelial growth inhibition (MGI) of P. expansum (-51.37 ±3.01%) whose negative value reflects even supportive effect of the EO on the microscopic fungus growth. On the other hand, GMEO at this concentration (250 μL.L-1) resulted in the strongest inhibitory action (MGI: 54.15 ±1.15%) against growth of P. chrysogenum. Based on the findings it can be concluded that GMEO in the vapor phase is not an effective antifungal agent against the growth of P. expansum inoculated on bread; however, its antifungal potential manifested against P. chrysogenum suggests GMEO to be an appropriate alternative to the use of chemical inhibitors for bread preservation.

The beneficial effects of Citrus fruits and their secondary metabolites on the cardiovascular system are well established. Moreover, growing evidence suggests beneficial role for prevention of obesity and related dysfunctions. Citrus reticulata Blanco (Rutaceae) is one of the most consumed Citrus fruits, but it is poorly investigated. Mandarin juice obtained from C. reticulata fruits, collected in the Horti Simplicium of Pisa Charterhouse, presents a high amount of flavanone glycosides, including hesperidin and a number of polymethoxyflavonoids, in particular nobiletin and tangeretin. On Wistar rats fed with a high fat diet for 21 days, mandarin juice significantly contained the percentage weight gain, reduced visceral adipose tissue and the inflammatory markers TNF and IL-6. Furthermore, mandarin juice influenced irisin pathway, increasing its plasma levels. Finally, supplementation with mandarin juice contributed to improve mitochondrial membrane potential, partially compromised with high fat diet, making mitochondria less susceptible to harmful events, such as ischemia. Taken together, these results suggest that C. reticulata, through its main metabolites, is able to produce beneficial effects in metabolic syndrome and to promote browning process, through involvement of the novel interesting irisin pathway.

Most of the commercially important citrus scion cultivars are susceptible to Huanglongbing (HLB), which is the most devastating disease the citrus industry has ever faced. Because the rootstock can influence the performance of the scion in various ways, including disease and pest tolerance, use of superior rootstocks can assist citrus growers with minimizing the negative effects of HLB. The objective of this study was to assess rootstock effects on the horticultural performance and early production potential of ‘Hamlin’ sweet orange (Citrus sinensis) trees in commercial field settings under HLB-endemic conditions. Two field trials were conducted in different locations in Central and Southeast Florida. The trials were established in 2015 and included 32 diverse diploid and tetraploid rootstock cultivars and advanced selections. One trial was performed in Highlands County, FL, on a poorly drained flatwoods-type site. Another trial was performed in Polk County, FL, on a well-drained sandy Central Florida Ridge site. Horticultural traits including tree height, canopy volume, trunk diameter, canopy health, leaf nutrient content, yield, and fruit quality were assessed during the 2018–19 and 2019–20 production years. Significant differences were found among trees on different rootstocks for most of the measured traits, particularly tree vigor and productivity, but rootstock effects also varied by location. Rootstocks that induced large tree sizes, such as the diploid mandarin × trifoliate orange hybrids ‘X-639’, ‘C-54’, ‘C-57’, and ‘C-146’, also induced higher yield, but with lower yield efficiency. Most of the tetraploid rootstocks significantly reduced tree size, among which ‘Changsha+Benton’, ‘Green-3’, ‘Amb+Czo’, ‘UFR-3’, and ‘UFR-5’ induced high yield efficiency. Therefore, these rootstocks have the potential to be used in high-density plantings. However, trees on some of these small size-inducing rootstocks had a higher mortality rate and were more vulnerable to tropical force winds. This study provides important information for the selection of rootstocks with the greatest production potential in an HLB-endemic environment, especially during the early years of production.

Made available in DSpace on 2021-06-25T11:48:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA) from Brazil Coatings are generally applied to fruit as microemulsions, but nanoemulsions are still experimental. 'Nova' mandarins (Citrus reticulata) were coated with shellac or carnauba (Copernica cerifera) microemulsions or an experimental carnauba nanoemulsion; these were compared with an uncoated control during storage for 7 days at 20 degrees C. Coatings were also tested on 'Unique' tangors (C. reticulata x C. sinensis) stored for 14 days at 10 degrees C followed by a simulated marketing period of 7 days at 20 degrees C. Fruit quality evaluations included weight loss, gloss, soluble solids (SS), titratable acidity (TA), pH, SS/TA ratio, internal CO2, O-2, fruit juice ethanol, and other aroma volatile content. Sensory visual shine and tangerine (C. reticulata) flavor rank tests after storage were conducted, followed by an off-flavor rating. The carnauba waxes resulted in less weight loss compared with the uncoated control and shellac coating during both experiments. There were no differences in gloss measurements of 'Nova' mandarins; however, shellac-coated fruit ranked highest for shine in a sensory test. For 'Unique' tangors, initially, shellac showed the highest gloss (shine) measurement; however, at the end of storage, the nanoemulsion exhibited the highest gloss, although it was not different from that of the microemulsion. Similarly, after storage, the nanoemulsion ranked highest for visual shine, although it was not different from that of the microemulsion. There were only minor differences in SS, TA, pH, and SS/TA among treatments. The internal CO2 gas concentration and juice ethanol content generally increased and internal O-2 decreased during storage. The highest levels of CO2 and ethanol were found for the shellac treatment, as was the lowest O-2, indicating anaerobic respiration. There were only minor differences among the other coating treatments; however, they were only sometimes different from those of the control, which generally had the highest O-2, lowest CO2, and lowest ethanol. Shellac and the carnauba microemulsion also altered the volatile profile more than the control and the nanoemulsion did, especially for 'Unique' tangors. For 'Unique' tangors, the control and nanoemulsion ranked highest for tangerine flavor and had the least off-flavor at the end of storage. Among the coatings tested, the carnauba emulsions demonstrated less water loss, imparted more sustainable gloss, and caused less ethanol production than shellac, with the nanoemulsion exhibiting higher gloss measurements, less modifications of the atmosphere and volatile profile, and, consequently, better flavor compared with the microemulsion. Sao Paulo State Univ, Sch Pharmaceut Sci, BR-14800901 Araraquara, SP, Brazil ARS, US Hort Res Lab, USDA, 2001 South Rock Rd, Ft Pierce, FL 34945 USA Embrapa Instrumentacao Brazilian Agr Res Corp, BR-13560970 Sao Carlos, SP, Brazil Sao Paulo State Univ, Sch Pharmaceut Sci, BR-14800901 Araraquara, SP, Brazil CAPES: PDSE/201688881.132643/2016-01 FAPESP: 2016/23419-5 CNPq: 407956/2016-6

Mandarin fruits are one of the most popular among the Citrus genus. They are consumed because of their nutritional and health benefits, as well as pleasant taste and smell. This paper describes the identification and characterization of Penicillium expansum, isolated from molded mandarin fruits. The obtained isolates were cultivated on five media [Czapek Yeast Autolysate agar (CYA), MEA (Malt extract agar), Creatine sucrose agar (CREA), Yeast extract sucrose agar (YES), and Oatmeal agar (OA)] and at five different incubation temperatures (5, 15, 25, 30, and 37 ?C). Isolates were sequenced for two molecular loci: internal transcribed spacer and beta-tubulin. Based on the results from morphological, physiological, molecular, and phylogenetic analyses, the recovered isolates were identified as P. expansum. The isolated species was confirmed as pathogenic to mandarin fruits in a pathogenicity test. To the best of our knowledge, this is the first report of P. expansum as a postharvest pathogen of mandarin fruit in Serbia.

Essential oils (EO) from aromatic and medicinal plants generally perform a diverse range of biological activities because they have several active constituents that work in different mechanisms of action. EO from Citrus peel have an impressive range of food and medicinal uses, besides other applications. EO from Citrus reticulata, C. sinensis and C. deliciosa were extracted from fruit peel and analyzed by GC-MS. The major constituent of EO under evaluation was limonene, whose concentrations were 98.54%, 91.65% and 91.27% for C. sinensis, C. reticulata and C. deliciosa, respectively. The highest potential of inhibition of mycelial growth was observed when the oil dose was 300 μL. Citrus oils inhibited fungus growth in 82.91% (C. deliciosa), 65.82% (C. sinensis) and 63.46% (C. reticulata). Anti-Sclerotinia sclerotiorum activity of 90% pure limonene and at different doses (20, 50, 100, 200 and 300 μL) was also investigated. This monoterpene showed to be highly active by inhibiting 100% fungus growth even at 200 and 300 μL doses. This is the first report of the in vitro inhibitory effect of natural products from these three Citrus species and its results show that there is good prospect of using them experimentally to control S. sclerotiorum, in both greenhouse and field conditions.

The world's energy needs generally come from non-renewable sources. In other circumstances, some research on renewable energy is being developed from a variety of different sources, one of which is biomass. Biomass changes the energy system towards the modernization of the bioenergy system by utilizing the concept of biochemical systems (BESs). A microbial fuel cell is known as one of the renewable technologies that convert biomass with the help of microbes to produce electricity. This research is based on a microbial fuel cell based on ecoenzyme Citrus reticulata known as Ecoenzyme fuel cell to determine the electrical value (voltage, current, and power density). Ecoenzyme was made from orange peel waste, molasses, and water with a ratio of 3: 1: 10 and fermented for a month. Meanwhile, the electrode device used was a pencil graphite. Some treatments were carried out to optimize the performance of the system based on the number of electrodes (one pair and three pairs), and the stirring conditions, stirring at 200 rpm and without stirring (0 rpm). The EFC system was run for four weeks (600 hours) with the highest voltage obtained at 650 mV and current at 29.55 mA. The ecoenzyme produced the most significant power density of 750 W/m2 in the treatment of 3 electrode pairs with a stirring speed of 200 rpm. The influence of electrodes and stirring in the MFC system upsurged the electrical value output by 53.7% for a pair of electrodes and 142% for three electrode pairs. Further development will continue to be done to improve the performance and output of the Ecoenzyme fuel cell system as a future renewable energy source in Indonesia.

Repellents are effective personal protective means against outdoor biting mosquitoes. Repellent formulations composed of EOs are finding increased popularity among consumers. In this study, after an initial screening of 11 essential oils (EOs) at the concentration of 33 μg/cm2, five of the most repellent EOs, Perovskia atriplicifolia, Citrus reticulata (fruit peels), C. reticulata (leaves), Mentha longifolia, and Dysphania ambrosioides were further investigated for repellent activity against Aedes aegypti mosquitoes in time span bioassays. When tested at the concentrations of 33 μg/cm2, 165 μg/cm2 and 330 μg/cm2, the EO of P. atriplicifolia showed the longest repellent effect up to 75, 90 and 135 min, respectively, which was followed by C. reticulata (peels) for 60, 90 and 120 min, M. longifolia for 45, 60 and 90 min, and C. reticulata (leaves) for 30, 45 and 75 min. Notably, the EO of P. atriplicifolia tested at the dose of 330 μg/cm2 showed complete protection for 60 min which was similar to the commercial mosquito repellent DEET. Gas chromatographic-mass spectrometric analyses of the EOs revealed camphor (19.7%), limonene (92.7%), sabinene (24.9%), carvone (82.6%), and trans-ascaridole (38.8%) as the major constituents of P. atriplicifolia, C. reticulata (peels), C. reticulata (leaves), M. longifolia, and D. ambrosioides, respectively. The results of the present study could help develop plant-based commercial repellents to protect humans from dengue mosquitoes.

Starch is a biodegradable polymeric carbohydrate that can easily form films and coatings and can readily be obtained from some food industry by-products and wastes, which may contribute to the circular bioeconomy. In this work, we studied the potential of two edible coating emulsions based on pregelatinized potato starch (PPS) and glyceryl monostearate (GMS) alone (F6 and F10) or formulated with the food additive sodium benzoate (SB, 2%) (F6/SB and F10/SB) to control sour rot, an important citrus postharvest disease caused by the fungus Geotrichum citri-aurantii, and maintain postharvest quality of cold-stored ‘Orri’ mandarins. The PPS-GMS coating application was compared to dipping in water (uncoated controls) and dipping in a 2% SB (w/v) aqueous solution. The results showed that the coating F10/SB was the most promising treatment to control sour rot on mandarins, with reductions in disease incidence with respect to the uncoated control samples of 94, 69, and 55% after 2, 4, and 6 weeks of storage at 5 °C, respectively. Coatings formulated without SB were ineffective. Regarding fruit quality, the coating F10 was the most effective to reduce weight loss, maintain firmness, and provide gloss on mandarins stored at 5 °C for up to 6 weeks followed by a shelf-life period of 1 week at 20 °C. The addition of SB to the PPS-GMS coatings adversely affected these coating properties, but the coating F10/SB still reduced weight loss compared to uncoated controls without negatively affecting the fruit physicochemical (juice titratable acidity, soluble solids content, and volatiles content) and sensory quality (overall flavor, off-flavors, external aspect). Overall, the coating F10/SB showed the greatest potential for commercial use as an efficient and environmentally friendly alternative to conventional fungicides and waxes for sour rot control and quality preservation of cold-stored mandarins.

The green, sustainable, and inexpensive creation of novel materials, primarily nanoparticles, with effective energy-storing properties, is key to addressing both the rising demand for energy storage and the mounting environmental concerns throughout the world. Here, an orange peel extract is used to make cobalt oxide nanoparticles from cobalt nitrate hexahydrate. The orange peel extract has Citrus reticulata, which is a key biological component that acts as a ligand and a reducing agent during the formation of nanoparticles. Additionally, the same nanoparticles were also obtained from various precursors for phase and electrochemical behavior comparisons. The prepared Co-nanoparticles were also sulfurized and phosphorized to enhance the electrochemical properties. The synthesized samples were characterized using scanning electron microscopic and X-ray diffraction techniques. The cobalt oxide nanoparticle showed a specific capacitance of 90 F/g at 1 A/g, whereas the cobalt sulfide and phosphide samples delivered an improved specific capacitance of 98 F/g and 185 F/g at 1 A/g. The phosphide-based nanoparticles offer more than 85% capacitance retention after 5000 cycles. This study offers a green strategy to prepare nanostructured materials for energy applications.

Aphids are serious pests of a wide range of agricultural crops, including pomegranates and grapevines. In addition, due to the negative environmental impacts of chemical insecticides, these pests are developing important resistance against aphicides. Therefore, one alternative method to control aphids is the use of essential oils (EO). The present study aimed to evaluate the insecticidal activity of Citrus aurantium and C. reticulata peel EO at different concentrations and with different exposure periods to pomegranate and grapevine aphids, Aphis punicae and A. illinoisensis via the topical application method under laboratory conditions. The results reveal that C. aurantium L. EO had greater toxicity against pomegranate and grapevine aphids, with LC50 of 0.37 and 0.82 μL/mL, respectively, at 48 h after application. The highest repellence effect was estimated for C. aurantium EO, at 2.5 μL/cm2, on A. punicae, with a value of 100% after an exposure time of 3 h, in contrast to the 88% repellence estimated for A. illinoisensis. The GC-MS investigation of both essential oils identified limonene, 3-carene, pinene, and p-cymene as active substances that could be attributed to the effects observed. Overall, our results offer a potential tool to control the two aphid species and could help in the development of integrated insect management in pomegranate and grapevine fields.

To identify factors that may reduce mandarin (Citrus reticulata) and orange (Citrus sinensis) consumer acceptance and to acquire information on current consumer thoughts and perceptions, a series of eight focus groups were held in a college town in northern California: four with children and four with adults. Adults mentioned cost proportionately more (P ≤ 0.05) often than children, as well as farm to fork, purchasing preferences, and seasonality. Children mentioned eating preferences, social use, and healthiness more often (P ≤ 0.05). Flavor and taste were important to both age groups, as well as ease of peeling. Both ages viewed oranges as slightly too large and messier than mandarins. Adults felt frustration that oranges and mandarins lack flavor and that quality is not consistent. Many indicated they would be willing to pay more for consistent quality. Children reported relying on availability, appearance, and the basic tastes to guide their choices and did not express a clear preference between mandarins and oranges. Development of a fruit intermediate in size between an orange and a mandarin, either a small orange or a large mandarin, would potentially satisfy an untapped area of the market. Other potential areas of consumer interest are in fruits with edible peels, like kumquats (Citrus japonica) and in more unique, identifiable varieties such as Cara Cara oranges.

Ocimum basilicum (sweet basil) and Laurus nobilis (bay leaves or laurel) have been used in traditional medicine for centuries, and also extensively employed as spices for adding aroma and flavor to various food products. Citrus reticulata (mandarin) is mainly used in food industry for juice production, while its peel as main byproduct contains high concentration of valuable substances. The samples were collected in Lastva Grbaljska (Montenegrin coast) and purchased from the market. Since the oxidative stress results in development of numerous diseases, among them neurodegeneration and diabetes, the antioxidant activity, antineurodegenerative and antidiabetic activities were analyzed, aiming to compare potential of plants cultivated under natural conditions and commercially purchased from the market, as well as to compare the effect of different solvents applied in the extraction process. Water, methanol and acetone extracts of leaves and peel were tested by DPPH and total reducing power (TRP) methods for determination of antioxidant activity, and by acetylcholinesterase (AChE) and α-glucosidase inhibition assays for analyzing the other activities. Total phenolic (TPC) and flavonoid (TFC) contents were also determined. The acetonic extract of L. nobilis from Lastva showed the highest TPC, DPPH, TRP, and α-glucosidase inhibition, while water extract of commercial L. nobilis exhibited the highest AChE inhibition. The leaves of L. nobilis are demonstrated to be promising antioxidant, antineurodegenerative and antidiabetic agent.

The peel of Citrus reticulata can be useful as a kind of traditional Chinese medicine in China. The circular complete chloroplast genome of Citrus reticulata was 160,101 bp in length with the typical quadripartite structure of angiosperms, including 87,721 bp large single-copy region (LSC), 18,394 bp small single-copy region (SSC) of and a pair of 26,993 bp inverted repeat (IR) regions. The overall nucleotide composition of chloroplast genome sequence is 30.5% A, 31.0% T, C (19.6%), G (18.9%), and the total G + C content of 38.5%. A total of 138 genes were annotated in chloroplast genome of C. reticulata. The phylogenetic tree result showed that C. reticulata was evolutionarily close to Citrus sinensis in the family Rutaceae the genus Citrus by the maximum-likelihood (ML) method.

Background: Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen, considered a leading cause of acute and chronic infections in immunocompromised patients. P. aeruginosa uses quorum sensing to control virulence and biofilm formation. To combat this human-resistant pathogen increasing attention has been paid to anti-QS compounds from natural products as potential therapeutic agents. Purpose: To assess the efficacy of C. paradisi (grapefruit) and C. reticulata (mandarin) commercial EOs (obtained by cold-pressing and cold-pressing followed by steam distillation, named EOP and EOPD, respectively) and their majority component, limonene, in inhibiting the effect of QS controlled virulence factors of P. aeruginosa PAO1 and PA14 in a C. elegans infection model. Results: C. paradisi and C. reticulata EOs at 0.125% (v/v) significantly inhibited the in vitro biofilm formation of PAO1 and PA14 strains between 40-50%. This EOs concentration, safe for C. elegans according to the survival and brood size assays, rescued the nematodes from P. aeruginosa infections, reducing their death rate by 20-30% in the paralysis assay, and increasing worm lifespan with median survivals of 6 and 5, respectively, in the slow killing assay (median survival of 3 for non-treated worms). Limonene protected nematodes from death in these assays although less effectively than both EOs species. Grapefruit EOs rescued the nematodes in 45-50% from phenazine-death, while mandarin EOs and limonene rescued them in 30%. In the food choice assay, worms felt more attracted to the PA14 grown with 0.125% of mandarin and grapefruit EOs or limonene spots (with CI=0.11 to 0.18). Conclusion: Our results suggest that C. paradisi and C. reticulata EOPDs, with lower commercial value but similar in vivo effects than EOPs, are sources of anti-QS agents for controlling P. aeruginosa infections, therefore should be considered as potential candidates for the development of novel therapeutics against persistent microorganisms.

International audience; Low temperatures during winter are one of the main constraints for citrus crop. Polyploid rootstocks can be used for improving tolerance to abiotic stresses, such as cold stress. Because the produced fruit are seedless, using triploid scions is one of the most promising approaches to satisfy consumer expectations. In this study, we evaluated how the triploidy of new citrus varieties influences their sensitivity to natural chilling temperatures. We compared their behavior to that of diploid citrus, their parents (Fortune mandarin and Ellendale tangor), and one diploid clementine tree, as reference, focusing on photosynthesis parameters, oxidative metabolism, and volatile organic compounds (VOC) in leaves. Triploid varieties appeared to be more tolerant than diploid ones to natural low temperatures, as evidenced by better photosynthetic properties (P-net, g(s), F-v/F-m, ETR/P-net ratio), without relying on a better antioxidant system. The VOC levels were not influenced by chilling temperatures; however, they were affected by the ploidy level and atypical chemotypes were found in triploid varieties, with the highest proportions of E-beta-ocimene and linalool. Such compounds may contribute to better stress adaptation.

A partir de un sondeo a 203 citricultores en Andalucía, se identifican los principales canales y agentes implicados en la comercialización de cítricos en la Comunidad autónoma y se analizan los criterios de fijación de los precios. Finalmente, se realiza un análisis las ventajas ofrecidas por los distintos sistemas de comercialización utilizados y de las principales problemáticas del sector mencionadas por los productores.

The original publication is available at https://doi.org/10.17660/ActaHortic.2020.1268.36, The external and internal quality of citrus fruit determines consumer acceptance, thereby driving the consumption and demand for fresh fruit. Emphasis is placed on producing a high volume of fruit of good quality, and it is known that light intensity is especially important in influencing sugar content, rind color, and blemish incidence. Extreme environmental conditions are challenging controllable factors. Therefore shade netting is used especially on fruit crops for protection against dramatic climatic events that affect the appearance of the fruit, i.e., excess sunlight, wind, and hail. The study was conducted on 'Nadorcott' mandarin trees planted in 2012 in a commercial orchard in Citrusdal, Western Cape province, South Africa. The aim of this study was to determine the influence of 20% white shade nets on the quality of 'Nadorcott' mandarin fruit. Monthly evaluation of fruit size, rind color, internal quality parameters (°Brix/citric acid ratio) and the incidence of sunburn was performed. The fruit diameter was not influenced by shade net in 2016; however, in 2017 a larger fruit diameter was measured for shade net fruit. Rind color development and internal quality were not influenced negatively by the treatment. Shade net was effective, reducing the incidence of sunburn significantly in both seasons, 2016 and 2017. Moreover, postharvest fruit quality was not negatively affected by the shade net treatments. In summary, our results indicate that shade-netting is a potential preventative technology ensuring unblemished and high quality in 'Nadorcott' mandarins, but further studies are required to evaluate the influence of tree age and microclimatic effect on fruit production and postharvest storage behavior in other citrus cultivars.

International audience; The green revolution and globalization have profoundly transformed agri-food systems, leading to standardized food products of diminished taste quality. Geographical Indications (GIs) have emerged as powerful regulatory tools for sustaining alternative quality models. In this paper, we analyze GIs as governance tools for “terroir niches”, viewed as sociotechnical systems whose functioning is influenced by specific resources. Building on this framework, we study the reconfiguration of the Corsican clementine production area under a recent Geographical Indication. We show that the innovation trajectory was driven by specific resources (climate, with-leaf marketing), leading to the emergence of a niche that conflicted with the rules of the citrus regime. The implementation of a GI in the early 2000s strengthened this endogenous innovation pathway since it gave the niche renewed protection and prompted systemic changes. These results open prospects for cross-fertilization between GI studies and the Multi-Level Perspective on sustainability transitions.

The objective of the study was to elucidate the best combination of ethylene dose and exposure time aiming the degreening of ‘Ponkan’ tangerines. Fruits harvested with fully green peel were placed in airtight boxes, exposed during 24, 48 and 96 h to ethylene gas at concentrations of 0, 5, 10, 20 and 40 µL L-1, at a temperature of 20 ± 1°C and 90 ± 5% of relative humidity. On every 24 h the fruits were evaluated for color, Hue angle, total chlorophyll and carotenoids in the peel, solutes leakage, soluble solids, titrable acidity, CO2 production and fresh fruit weight loss. The degreening was more pronounced in fruits exposed to ethylene for 96 h, independently the concentration. The electrolytes leakage peel increased linearly in fruit-control and those exposed to ethylene for 24 h. In fruits treated for 48 and 96 h, electrolyte leakage was observed only during ethylene exposure. The accumulated fresh mass loss did not exceeded 1% in the fruits. The ethylene dose did not affected the fruit respiratory behavior. The best combination aiming fruit degreening was the exposure during 96 h with 5 μL L-1 of ethylene, followed by 48 to 72 hours of storage after treatment.

Non-small cell lung cancer (NSCLC) accounts for most cases of lung cancer. The peel oil of Mandarin Citrus reticulata Blanco cv. Dancy (MPO) is a natural source of essential oils and carotenoids. Volatile and non-volatile lipid compounds were characterized by chromatographic methods. We demonstrate that MPO causes a dose-dependent growth inhibition of NSCLC model cells (A549) in culture and tumour growth in vivo of the same cells implanted in nude mice fed with MPO-supplemented diets. MPO induced cell cycle arrest mainly at the G0/G1 phase and reduced the amount of membrane-bound Ras protein along with apoptosis induction. No toxicological effect was found in liver parameters analysed in treated mice and histopathological analyses of their organs did not show any morphological changes. In conclusion, the data suggest that MPO possesses significant antitumor activity without causing systemic toxicity, proposing it as a dietary supplement that may be helpful in cancer prevention. Fil: Castro, Maria Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentina Fil: Rodenak Kladniew, Boris Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentina Fil: Massone, Adriana Raquel. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Patología. Laboratorio de Patología Especial Veterinaria "Dr. Bernardo Epstein"; Argentina Fil: Polo, Monica Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentina Fil: García de Bravo, Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentina Fil: Crespo, Rosana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentina

Introduction – The tangor cv. Ortanique presents positive characteristics for the fresh fruit export market, however little is known about this genotype in Brazil. In this study, we evaluated the ideal harvest time on two rootstocks, the fruit juice carotenoid content and possible postharvest storage of 'Ortanique' fruit. Materials and methods – The cultivar was grafted on 'Swingle' citrumelo and Poncirus trifoliata and was evaluated to the following variables: plant height, diameter and canopy volume, fruit physical and chemical quality [mass, soluble solids (SS), titratable acidity (TA) and the ratio (SS/TA)], production and productive efficiency in each graft combination. Carotenoids content of 'Ortanique' fruit juice grafted on 'Swingle' was qualified by HPLC. The optimal storage time of 'Ortanique' (with or without wax, stored at 10 °C or at room temperature) were determined for six weeks storage. Results and discussion – The rootstock 'Swingle' provided great growth and plant production of 'Ortanique' plants while Poncirus trifoliata delayed fruit maturation. The 'Ortanique' fruit juice contained high levels of β-cryptoxanthin and cis-violaxanthin and the fruit could be stored at 10 °C for six weeks without losing quality. Conclusion – The 'Ortanique' tangor has productive potential for commercial cultivation in Brazil, being late-maturing, its fruit high in carotenoid content and possibly well adapted to long storage for export.

Background: Microorganisms resistant to most antibiotics are rapidly spreading, and there is an urgent and continuous need for novel antimicrobial compounds. The genus Citrus belongs to the family Rutaceae has many biologically active secondary metabolites. Objectives: The purpose of this study was to evaluate antimicrobial activity of essential oil and extract of Lemon (Citrus limon), Mandarin (Citrus reticulata) and Pummelo (Citrus grandis) against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Salmonella typhi. Materials and Methods: The fresh Citrus leaves were shade-dried and powdered. Antimicrobial metabolites were extracted from them by 80% methanol for extract and using a Clevenger-type apparatus for essential oil. Eight different concentrations of the each leaf extract and essential oil were prepared. The antimicrobial susceptibility assay of Citrus leaves metabolites were subjected against four bacterial strains by agar disc diffusion and E-test method. Results: In this study, minimum inhibitory concentrations (MIC) of different Citrus leaf extracts were determined against all four food-borne pathogens. The C. grandis leaf essential oil had potent antimicrobial activity against all four pathogens, and the C. limon leaf essential oil was effective on Gram-positive bacteria. S. typhi was resistant against two leaves essential oils. Conclusions: The results showed that there was no antimicrobial activity effect in all extracts on tested bacteria. In this study, the antibacterial effect of essential oil of Citrus leaves on four strains of pathogenic microorganisms was confirmed. The C. grandis leaf essential oil had the most powerful antimicrobial properties, suggesting its potential application as natural preservative in foods or an effective medicine against different pathogenic microbes. Key words: Antibacterial activity, E-test, Citr

Triploid-breeding programs in citrus are key tool to develop seedless cultivars. Obtaining triploid citrus hybrids may be achieved through different strategies, such as the exploitation of female unreduced gamete in crosses between diploid parents and diploid by tetraploid sexual hybridizations, in which tetraploid genotypes can be used as male or female parents. Genetic configuration of triploid populations from interploid crosses greatly depends on the chromosomic segregation mode of the tetraploid parent used. Here, we have analyzed the inheritance of the tetraploid ‘Moncada’ mandarin and compared the genetic structures of the resulting gametes when used as male and as female parent. The preferential chromosome pairing rate is calculated from the parental heterozygosity restitution (PHR) of codominant molecular markers, indicating the proportion between disomic and tetrasomic segregation. Tetraploid ‘Moncada’ both as female and male parent largely exhibited tetrasomic segregation. However, as female parent, one linkage group (LG8) showed intermediate segregation with tendency towards tetrasomic inheritance, while another linkage group (LG4) evidenced a clear intermediate segregation. On the other hand, when used as male parent two linkage groups (LG5 and LG6) showed values that fit an intermediate inheritance model with tetrasomic tendency. Significant doubled reduction (DR) rates were observed in five linkage groups as female parent, and in six linkage groups as male parent. The new knowledge generated here will serve to define crossing strategies in citrus improvement programs to efficiently obtain new varieties of interest in the global fresh consumption market. EEA Concordia Fil: Garavello, Miguel Fernando. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; Argentina Fil: Cuenca, José. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España. Fil: Garcia-Lor, Andrés. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España. Fil: Ortega, Neus. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España. Fil: Navarro, Luis. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España. Fil: Ollitrault, Patrick. Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD). Amélioration Génétique et Adaptation des Plantes (UMR Agap). Unité Mixte de Recherche; Francia Fil: Aleza, Pablo. Instituto Valenciano de Investigaciones Agrarias. Centro de Citricultura y Producción Vegetal; España.

A novel NAC transcription factor, CrNAC036, can interact with CrMYB68 to synergistically regulate the ripening process of citrus fruit by down-regulating the expression of 9-cis-epoxycarotenoid dioxygenase 5., Although abscisic acid (ABA) is a vital regulator of fruit ripening and several transcription factors have been reported to regulate ABA biosynthesis, reports of the effect of ABA on citrus ripening and the regulation of its biosynthesis by a multiple-transcription-factor complex are scarce. In the present study, a systematic metabolic, cytological, and transcriptome analysis of an ABA-deficient mutant (MT) of Citrus reticulata cv. Suavissima confirmed the positive effect of ABA on the citrus ripening process. The analysis of transcriptome profiles indicated that CrNAC036 played an important role in the ABA deficiency of the mutant, most likely due to an effect on the expression of 9-cis-epoxycarotenoid dioxygenase 5 (CrNCED5). Electrophoretic mobility shift assays and dual luciferase assays demonstrated that CrNAC036 can directly bind and negatively regulate CrNCED5 expression. Furthermore, yeast two-hybrid, bimolecular fluorescence complementation, and dual luciferase assays demonstrated that CrNAC036 interacted with CrMYB68, also down-regulating the expression of CrNCED5. Taken together, our results suggest that CrNAC036 and CrMYB68 synergistically inhibit ABA biosynthesis in citrus fruit by regulating the expression of CrNCED5.

Tetraploid clementine displays mainly tetrasomic inheritance. Genetic structures of 2n SDR and 2 × gametes from DD clementine are complementary and will guides triploids citrus breeding strategies. Triploid breeding is developed worldwide to create new seedless cultivars. Citrus triploid hybrids can be recovered from 2x × 2x sexual hybridizations as a consequence of the formation of unreduced gametes (2n), or from 4x × 2x interploid hybridizations in which tetraploid parents used are most often doubled-diploid (DD). Here we have analyzed the inheritance in doubled-diploid clementine and compared the genetic structures of gametes of DD clementine with SDR unreduced gametes of diploid clementine. Parental heterozygosity restitution (PHR) with DD parents depends on the rate of preferential chromosome pairing and thus the proportion of disomic versus tetrasomic segregations. Doubled-diploid clementine largely exhibited tetrasomic segregation. However, three linkage groups had intermediate segregation and one had a tendency for disomy. Significant doubled reduction rates (DR) rates were observed in six of the nine LGs. Differences of PHR between 2n SDR and 2x DD gametes were highest in the centromeric region and progressively decreased toward the distal regions where they were not significant. Over all markers, PHR was lower (two-thirds) in SDR 2n gametes than in DD-derived diploid gametes. The two strategies appear complementary in terms of genotypic variability. Interploid 4x × 2x hybridization is potentially more efficient for developing new cultivars that are phenotypically closer to the diploid parent of the DD than sexual hybridization through SDR 2n gametes. Conversely, 2x × 2x triploidisation has the potential to produce novel products with characteristics for market segmentation strategies.

Background and Aims The origin of limes and lemons has been a source of conflicting taxonomic opinions. Biochemical studies, numerical taxonomy and recent molecular studies suggested that cultivated Citrus species result from interspecific hybridization between four basic taxa (C. reticulata, C. maxima, C. medica and C. micrantha). However, the origin of most lemons and limes remains controversial or unknown. The aim of this study was to perform extended analyses of the diversity, genetic structure and origin of limes and lemons. Methods The study was based on 133 Citrus accessions. It combined maternal phylogeny studies based on mitochondrial and chloroplastic markers, and nuclear structure analysis based on the evaluation of ploidy level and the use of 123 markers, including 73 basic taxa diagnostic single nucleotide polymorphism (SNP) and indel markers. Key Results The lime and lemon horticultural group appears to be highly polymorphic, with diploid, triploid and tetraploid varieties, and to result from many independent reticulation events which defined the sub-groups. Maternal phylogeny involves four cytoplasmic types out of the six encountered in the Citrus genus. All lime and lemon accessions were highly heterozygous, with interspecific admixture of two, three and even the four ancestral taxa genomes. Molecular polymorphism between varieties of the same sub-group was very low. Conclusions Citrus medica contributed to all limes and lemons and was the direct male parent for the main sub-groups in combination with C. micrantha or close papeda species (for C. aurata, C. excelsa, C. macrophylla and C. aurantifolia – 'Mexican' lime types of Tanaka's taxa), C. reticulata (for C. limonia, C. karna and C. jambhiri varieties of Tanaka's taxa, including popular citrus rootstocks such as 'Rangpur' lime, 'Volkamer' and 'Rough' lemons), C. aurantium (for C. limetta and C. limon – yellow lemon types – varieties of Tanaka's taxa) or the C. maxima × C. reticulata hybrid (for C. limettioides – 'Palestine sweet' lime types – and C. meyeri). Among triploid limes, C. latifolia accessions ('Tahiti' and 'Persian' lime types) result from the fertilization of a haploid ovule of C. limon by a diploid gamete of C. aurantifolia, while C. aurantifolia triploid accessions ('Tanepao' lime types and 'Madagascar' lemon) probably result from an interspecific backcross (a diploid ovule of C. aurantifolia fertilized by C. medica). As limes and lemons were vegetatively propagated (apomixis, horticultural practices) the intra-sub-group phenotypic diversity results from asexual variations. (Resume d'auteur)

International audience; AbstractIn agriculture, not all sociotechnical niches seek to plant the seeds of further regime transition: Some niches are designed to last as stable subnetworks harboring alternative agri-food systems. However, such niches often interact with sociotechnical regimes, leading to controversies, conflicts, and threats to niches sustainability. This situation calls for proactive governance of niche-regime interactions. We studied the innovation process in the “Corsican clementine” niche, using semi-structured interviews and participant observation. We wondered how local actors have been dealing with three controversial innovations: a clementine variety, a biological pest control method, and a pruning technique. Cross-analysis of the three innovations shows that (i) the niche’s innovation pathway can be diverted by regime-driven innovations; (ii) to protect their niche, local actors set collective rules, both formal and informal; and (iii) controversies over technical innovations make niche-regime tensions more visible, leading local actors to make collective decisions for governing the innovation pathway. This study is the first to highlight the key role of sociotechnical controversies in niche governance.

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Protoplast fusion is a useful technique for citrus genetic improvement. Establishment of protoplast technology could produce triploid seedles citrus and new citrus genetic combination. The aim of this research was to establish protoplast isolation, protoplast fusion between pummelo ‘Nambangan’ (Citrus maxima) and keprok ‘Garut’ (C. reticulata), and its protoplast culture. Protoplasts were isolated from leaves of in vitro seedlings of pummelo ‘Nambangan’ and embryogenic callus of keprok ‘Garut’ with two different compositions of enzymes. The results showed that optimum enzymes compositions for cells mesophyl wall degradation were consisted of 0.5 % Onozuka cellulase RS10, 0.5 % Macerozyme R10 and 0.1 % Pectolyase Y23. Optimum enzymes composition for callus embryogenic cells wall degradation were 0.5 % Onozuka cellulase RS10 added with 0.5 % Macerozyme R10. Protoplast fusion was conducted with PEG-mediated. Protoplast mixture were incubated in 40 % PEG for 8-10 min and after that could be observed 40.6 % of unfused protoplasts, 4.6 % of homofused mesophyl protoplasts, 28.2 % of homofused callus protoplasts, 7.8 % of heterofused and 9.6 % of multifused protoplasts from mesophyl and callus. Cells divided at the first week and began to form cell colonies afterwards in liquid culture. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

La estrategia de uso múltiple (EUM) se caracteriza por el manejo de diferentes unidades ecogeográficas (microambientes) y de distintos componentes bióticos y físicos, como también el manejo de procesos ecológicos. En este trabajo se aborda la EUM aplicada a componentes bióticos- algarrobos (Prosopis spp.) y mandarinas (Citrus reticulata)- centrales en dos áreas distintas cultural, histórica y fitogeográficamente. Los Juríes está ubicado hacia el centro-este de la provincia de Santiago del Estero, y el Cerro Mártires es un paraje situado al sur de la provincia de Misiones. A través de la metodología etnobotánica cualitativa se registraron los usos de los taxa considerados, tanto en el pasado como en el presente, y su representación en los microambientes transitados por los pobladores en sus actividades cotidianas. Se observa que los usos actuales son construidos en función de la relación dinámica entre las comunidades, el ambiente y el contexto socioeconómico regional en cada época. Asimismo, los taxa tratados son considerados locales o “de la zona” independientemente de su carácter nativo/exótico, lo que evidencia la apropiación de estos recursos. Se discute el aporte de algarrobos y mandarinas a la sustentabilidad (tanto desde el punto de vista ecológico como social) de las comunidades campesinas, así como diversas estrategias de conservación. A estratégia do uso múltiplo (EUM) é caracterizada pelo uso de diferentes unidades eco-geográficas (microambientes) e diferentes componentes bióticos e físicos, assim como a gestão de processos ecológicos. Neste trabalho, o EUM foi aplicada aos componentes bióticos, algarrobos (Prosopis spp.) e tangerinas (Citrus reticulata) centrais em duas áreas históricas, cultural e fitogeograficamente diferentes: Los Juríes, que está localizado em direção ao centro-leste da província de Santiago del Estero, e Cerro Mártires que está localizado ao sul da província de Misiones. Através da metodologia etnobotânica qualitativa foram registradas as aplicações dos táxons considerados; tanto do passado e como no presente, e sua representação no microambientes percorridos pelas pessoas em suas atividades diárias. Nota-se que os usos atuais são construídos com base na relação dinâmica entre as comunidades, meio ambiente e contexto sócio-económico regional em cada período. Além disso, os táxons tratados são considerados locais ou “da zona”, independentemente do seu caráter exótico/nativo, o que mostra a apropriação desses recursos. A contribuição de algarrobos e tangerinas para a sustentabilidade das comunidades rurais é discutida (tanto do ponto ecológico e social) e várias estratégias de conservação The multiple use strategy (MUS) is characterized by the management of different eco-geographic units (microenvironments) and by different biotic and physical components, as well as by the management of ecological processes. In this study, the MUS was applied to biotic components, algarrobos (Prosopis spp.) and tangerines (Citrus reticulata), that are central in two areas that differ culturally, historically and phytogeographically. Los Juries is located towards the centreeast of Santiago del Estero province, while Cerro Martires is located to the south of Misiones province. Qualitative ethnobotanical methodology was applied and both past and present uses of these taxa have been recorded as well as their representation in those microenvironments transited by inhabitants during their daily activities. It can be observed that present uses are built on the basis of the dynamic relationship between communities, environment and regional socioeconomic context in each period. Furthermore, the treated taxa are considered local or “from the area” independent of their native/exotic character, which puts in evidence the appropriation of these resources. The contribution of algarrobos and tangerines to the sustainability of farming communities (both from the ecological as social point of view) is discussed, as well as diverse conservation strategies Fil: Riat, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; Argentina Fil: Stampella, Pablo César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; Argentina Fil: Pochettino, María Lelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; Argentina

En esta guía se recoge toda la información concerniente a las plagas de moluscos en citricultura: reconocimiento y control.

International audience; Citrus reticulata is considered one of the four main ancestral taxa of cultivated citrus and is widely associated with the mandarin horticultural group. However, several studies suggest introgressions of other taxa and the precise structure of the mandarin group is not known. To analyse the structuration of mandarin germplasm and the potential interspecific introgressions, 208 accessions were genotyped by the KASPar method, with sixty-seven single nucleotide polymorphism (SNP) markers mined in 27 nuclear genes and in clementine BAC-ends. These SNP markers were employed for the study of 208 genotypes comprised of 169 ` mandarin-like' genotypes and 39 genotypes belonging to ancestral taxa. Structure software was used to identify groups within the mandarin germplasm. Six mandarin groups were identified, some of them in agreement with the species defined by Tanaka. Many mandarins were located between these mandarin groups, indicating a high level of admixture between the identified parental groups. New insights in the organization of mandarin germplasm and its structure are presented in this work, which will be useful for better management of citrus germplasm collections.

Polyploid citrus arise by somatic and sexual polyploidization, and both have been used in triploid breeding programs. Sexual polyploidization is mainly achieved by first-division restitution (FDR) or second-division restitution (SDR) meiotic restitution mechanisms. In citrus, mostly SDR producing 2n ovule has been described. However, we obtained 72 tetraploid hybrids from 4x X 2x sexual hybridizations using two doubled-diploid mandarins as female parents ('Moncada' mandarin and 'Fina' clementine) and a diploid hybrid tangor as male parent (clementine X sweet orange—'CSO') suggesting 2n pollen formation. This material was used to confirm the existence of 2n pollen in Citrus and to analyze its origin. SSR and SNP molecular marker analyses revealed that 64 out of the 72 recovered tetraploid plants resulted from the fertilization of a reduced diploid female gamete by unreduced (diploid) pollen from 'CSO', whereas eight tetraploid plants arose from self-pollination of the tetraploid parent. The maximum-likelihood method based on parental heterozygosity restitution (PHR) of centromeric loci identified both FDR and SDR as the mechanisms leading to unreduced male gamete formation. From the 64 unreduced gametes produced by diploid 'CSO' tangor, 41 (64.1%) were originated by FDR, whereas 12 (18.8%) were significant for SDR. Non-conclusive results were obtained for 11gametes (17.2%). The pattern of PHR variation of markers located along the linkage group 2 confirmed our results at population level. To our knowledge, this is the first report of tetraploid citrus progenies arising from unreduced pollen and the first description of the coexistence of two meiotic restitution mechanisms (SDR and FDR) producing unreduced pollen in citrus.

Este documento muestra un nuevo modelo de sistema de cultivo en cítricos llamado Superintensivo, es decir, plantaciones de alta densidad con árboles de reducido vigor con unas 2.200 plantas/hectárea aproximadamente, marcos de plantación más estrechos y formación en setos mediante el empleo de la poda mecanizada, orientado a la recolección mecanizada con equipos cabalgantes sacudidores de follaje, tipo vendimiadora. Se dan a conocer los rasgos fundamentales de este tipo de sistema de cultivo así como las ventajas e inconvenientes que presenta el mismo.

O objetivo do trabalho foi avaliar o efeito de diferentes concentrações de fécula de mandioca na vida útil pós-colheita de frutos 'Mexerica Poncã' durante o armazenamento em temperatura ambiente em substituição ao filme de policloreto de vinila (PVC). Os frutos foram imersos em suspensões aquosas de fécula de mandioca a 0; 1; 2 e 3% (m:v) acrescidas de 0,5mL L-1 de óleo mineral Assist (Bayer Cropscience, da empresa Hoechst Schering AgrEvo UK Ltd. - Inglaterra) ou recobertos com PVC de 14µm de espessura, e armazenados a temperatura ambiente. As amostragens foram realizadas no tempo zero (início do experimento) e a cada dois dias, por oito dias. Foram avaliadas a perda de massa fresca, rendimento de suco, sólidos solúveis (SS), acidez titulável (AT), relação SS/AT e teor de ácido ascórbico. A perda de massa fresca aumentou durante o armazenamento, sendo mais acentuada na dose de 2%. A redução no teor de ácido ascórbico foi maior nos frutos recobertos com filme de PVC. A concentração de fécula de mandioca a 1% foi a que proporcionou melhores resultados quanto à manutenção da qualidade físico-química de frutos de 'Mexerica Poncã' durante oito dias de armazenamento. The objective of this study was to evaluate the effect of different concentrations of cassava starch in postharvest life of fruits 'Tangerine Poncã' during storage at room temperature instead the film of polyvinyl chloride (PVC). The fruits were immersed in aqueous suspensions of cassava starch at 0, 1, 2 and 3% (m/v) plus 0.5mL L-1 a mineral oil Assist (Bayer CropScience, company Hoechst Schering AgrEvo UK Ltd. - Inglaterra) and the film of polyvinyl chloride (PVC) of 14µm thick, and stored at room temperature. The samples were collected at time zero (day of the assembly of the experiment) and then every two days. We evaluated the weight loss, juice yield, soluble solids (SS), titratable acidity (TA), SS / TA and ascorbic acid. The weight loss increased during storage, being more pronounced at a dose of 2%. The reduction in ascorbic acid content was higher in fruits covered with PVC film. The concentration of cassava starch to 1% was the highest values for the maintenance of physical and chemical quality of fruits of 'Mexerica Poncã' during eight days of storage.

Bu çalışmada ticari olarak temin edilen Rutaceae familyasına ait Citrus reticulata Blanco uçucu yağı fizikokimyasal özellikleri ve kimyasal bileşimi incelenmiştir. Fizikokimyasal özellikleri kapsamında uçucu yağın yoğunluk, kırılma indisi ve spesifik çevirme açısı belirlenmiştir. Ayrıca gaz kromatografisi (GK) ve gaz kromatografisi (GK)-kütle spektrometresi (KS) analizi ile kimyasal bileşimi ortaya konmuştur. Uçucu yağın %99.9’una karşılık gelen 12 bileşik tanımlanmıştır. Ana bileşikler limonen (%73.1) ve g-terpinen (%16.0) olarak tespit edilmiştir. Elde edilen bulgular Avrupa Farmakopesi standartları ile karşılaştırılmış ve incelenen uçucu yağın bu standartlara uygun olduğu belirlenmiştir.

The production of cybrids, combining nucleus of a species with alien cytoplasmic organelles, is a valuable method used for improvement of various crops. Several citrus cybrids have been created by somatic hybridization. These genotypes are interesting models to analyze the impact of cytoplasmic genome change on nuclear genome expression. Herein, we report genome-wide gene expression analysis in leaves of a citrus cybrid between C. reticulata cv 'Willowleaf mandarin' and C. limon cv 'Eureka lemon' compared with its lemon parent, using a Citrus 20K cDNA microarray. Molecular analysis showed that this cybrid possesses nuclear and chloroplast genomes of Eureka lemon plus mitochondria from Willowleaf mandarin and, therefore, can be considered as a lemon bearing foreign mitochondria. Mandarin mitochondria influenced the expression of a large set of lemon nuclear genes causing an over-expression of 480 of them and repression of 39 genes. Quantitative real-time RT-PCR further confirmed the credibility of microarray data. Genes over-expressed in cybrid leaves are predominantly attributed to the functional category ''cellular protein metabolism'' whereas in the down-regulated none functional category was enriched. Overall, mitochondria replacement affected different nuclear genes including particularly genes predicted to be involved in mitochondrial retrograde signaling. Mitochondria regulate all cell structures even chloroplast status. These results suggest that nuclear gene expression is modulated with respect to new information received from the foreign organelle, with the final objective to suit specific needs to ensure better cell physiological balance.

Seedlessness is an important trait in the evaluation of commercial mandarin for fresh consumption. However, in the last decade, the presence of seeds in fruit of cultivars considered as seedless has become a problem in different citrus-growing areas because the commercial value is depreciated. Seeds have appeared concomitantly with the introduction of new cultivars that appear to be cross-compatible. To overcome this problem, different strategies have been explored, but a definitive answer is still elusive. The search for alternatives contrasts with how little is known about the basis of the problem: the pollen-pistil incompatibility reaction in mandarin, and the intercompatibility relationship between different cultivars. In this work, we characterized the pollen-pistil incompatibility in the two commonly grown mandarin cultivars Fortune and Nova, and evaluated the intercompatibility relationship between six cultivars with different genetic origins; these cultivars included Fortune (Citrus clementina Hort. ex Tan. × Citrus reticulata Blanco), Nova [(Citrus paradisi Macf. × C. reticulata) × C. clementina), Comune Clementine (C. clementina), Avana apireno (C. reticulata), Primosole (Citrus unshiu Marcov. × C. reticulata), and Simeto (C. unshiu × Citrus deliciosa Ten.). Following the controlled hand pollination in the field, we evaluated pollen tube performance after self- and cross-pollination, as well as intercultivar compatibility by observing pollen tube growth. The results show the self-incompatibility of these cultivars with the pollen tube having been arrested in the style, which explains their seedless condition when planted in solid blocks. The study of intercompatibility indicates a different pollen tube behavior depending on the genotype, as well as on the cross combinations. These results provide a basis to evaluate self- and intercompatibility in citrus, and the effect of close planting of some cultivars., Financial support for this research was provided by the Italian Ministry of Agriculture and Forestry, Project RAVAGRU (Advanced research in citriculture), publication no. 32; by the Italian Ministry of the University, Project PRIN ‘‘The productive process in fruit tree species: molecular, physiological, and agronomical aspects of floral incompatibility and strategies for its control’’; by the Minister of Science and Innovation, EU Feder (Project grant CICYT AGL-2006-13529-CO2-01/AGR); and by the Grupo de Excelencia del Gobierno de Aragón A-43.

The genetic and phytosanitary certification has to guarantee the quality of the propagation material also in Citrus. Traditional methods can be assisted by the techniques of in vitro culture, which are fundamental for the mass production of high quality plants. The encapsulation technology represents an innovative tool to combine the advantages of micropropagation with handling ease, storability, reduced size of the propagules, mechanization potentiality, transportability of the gamic seeds. In this work somatic embryos obtained from in vitro anther culture of the cultivar Mandarino Tardivo di Ciaculli (Citrus reticulata Blanco) were encapsulated in a sodium alginate matrix and synthetic seeds were obtained. The conversion ability in non sterile conditions of the synthetic seeds has been evaluated and the addition to the artificial endosperm of the fungicide Thiophanate-methyl did not limit the further development into plantlets of the encapsulated somatic embryos sown on paper (control) and on perlite. A high level of viability has been observed and conversion in ex vitro conditions on substrates similar to those used in the traditional nursery structures (perlite and paper-filter) has been obtained.

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease for which, thus far, there are no effective treatments. The pericarp of Citrus reticulata, as a traditional herbal drug, has been used for the clinical treatment of lung-related diseases in China for many years. In the present study, the amines from the pericarp of Citrus reticulata were isolated, and their hydrochlorides were prepared. The results of screening using cultured human embryonic lung fibroblasts (hELFs) revealed that, of the amines, 4-methoxyphenethylamine hydrochloride (designated as amine hydrochloride 1) possessed the most potent inhibitory effect. Further in vivo experiments using a rat model of bleomycin-induced pulmonary fibrosis demonstrated that the oral administration of amine hydrochloride 1 significantly lowered the hydroxyproline content in both serum and lung tissue, and alleviated pulmonary alveolitis and fibrosis. Immunohistochemical analysis revealed that amine hydrochloride 1 exerted its inhibitory effect against IPF through the downregulation of lung transforming growth factor (TGF)-β1 protein expression. Our results demonstrated that amine hydrochloride 1 prevented the development of bleomycin‑induced lung fibrosis in rats. Thus, our data suggest that the amines from the pericarp of Citrus reticulata have therapeutic potential for use in the treatment of IPF.

International audience; Different physiological behavior of a wide range of varieties and species belonging to the Citrus genus was analyzed when subjected to salt stress with the aim to seek new sources of tolerance that might be specie-specific. Our goal was to use physiological results obtained along a salt stress in order to clarify if it would be possible to associate them with the known citrus genetic diversity. For that purpose, we have selected 20 different genotypes representing the major species on the basis of the genetic diversity of Citrus genus complemented with one intergeneric hybrid Carrizo citrange (C. sinensis 9 P. trifoliata). A moderate salt stress of 75 mM of NaCl was applied for 12 weeks. For control plants, the main parameters contributing for more than 25 % to the diversity on the two axes of principal component analysis (PCA) were chlorophyll content, photosynthesis and Fv/ Fm under light. However, the dispersal of species and varieties on the PCA did not show any particular structure. Under salt stress condition, four parameters (leaf chloride content, leaf chlorophyll content, photosynthesis and stomatal conductance) contributed more specifically to the dispersion on PCA representation with more than 15 % of contribution for each parameter. Large differences were observed within citrus genus: mandarin and pummelo presented good tolerance to salt stress while citron was very sensitive. Furthermore, all secondary genotypes that presented good tolerance to salt tolerance shared mandarin or pummelo as female parent.

Verniere, C., Perrier, X., Dubois, C., Dubois, A., Botella, L., Chabrier, C., Bove, J. M., and Duran Vila, N. 2004. Citrus viroids: Symptom expression and effect on vegetative growth and yield of clementine trees grafted on trifoliate orange. Plant Dis. 88:1189-1197. Citrus are natural hosts of five viroid species: Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), Hop stunt viroid (HSVd), Citrus viroid III (CVd-III), and Citrus viroid IV (CVd-IV). CEVd and specific sequence variants of HSVd are the causal agents of the wellknown diseases of citrus, exocortis and cachexia. Other viroids have been found to induce different degrees of stunting. Since commercial citrus trees are commonly infected with mixtures of these viroids, only limited information is available on their effect in species other than Etrog citron. A field assay was conducted to establish the effect of each viroid on Commune clementine trees grafted on Pomeroy trifoliate orange. Infected trees were periodically monitored over a 12-year period (1990 to 2002) for symptom expression, growth, and fruit yield. Only CEVd caused bark scaling on the trifoliate orange rootstock and marked dwarfing, both characteristic of exocortis disease as initially described. In addition, very conspicuous bumps were observed in the wood of the rootstock after removing the bark. Only those HSVd variants, previously characterized as pathogenic in several cachexia-sensitive species, induced pits and gum deposits characteristic of this disease in the clementine scion. Bark cracking symptoms on the trifoliate orange rootstock were also observed. They were associated with CVd-IV, HSVd, or CEVd infection, but in the latter, they were only clearly observed in trees that showed mild scaling. Other abnormalities (deep pits, crests, and gummy pits) were not associated with viroid infection. No specific symptoms resulted from infection with CBLVd and CVd-III. HSVd, CVdIV, and CBLVd had little or no effect in growth and yield, whereas CEVd and CVd-III caused a significant reduction of growth and yield, which became more pronounced over time with CEVd infection. Yield reduction was associated mainly with loss of production of large fruits. In general, there was a good correlation between reduction in vegetative growth and yield.

Objetivou-se estudar a influência do fotoperíodo no cultivo in vitro de embriões imaturos oriundos do cruzamento entre tangerineira ‘Poncã’ e laranjeira ‘Pera’. Os embriões foram extraídos de frutos com 3 - 4 cm de diâmetro e inoculados em meio MS, adicionado de GA3 e carvão ativado nas concentrações de 0,3 mg.L-1 e 1 mg.L-1, respectivamente, previamente autoclavado a 121oC por 20 minutos. Os tratamentos constaram dos seguintes fotoperíodos: 8, 10, 12, 14, 16, 18 e 24 horas de luz contínua, na intensidade luminosa de 43 µM.m-2.s-1, a 27ºC, em estufas tipo B.O.D. O tratamento com 16 horas de luz contínua foi realizado em sala de crescimento em intensidade luminosa de 35 µM.m-2.s-1. O experimento foi conduzido em delineamento inteiramente casualizado, com quatro repetições de três tubos de ensaio cada uma. Após 60 dias, melhores resultados para altura da parte aérea, número de folhas, peso da matéria fresca da parte aérea, comprimento das raízes e peso da matéria fresca das raízes foram obtidos com fotoperíodos de 8, 10, 12, 14, 18 e 24 horas. Fotoperíodo de 16 horas proporciona menor desenvolvimento de embriões imaturos. It was aimed to study the influence of the photoperiod on in vitro culture of immature embryos from ‘Poncã’ mandarin and ‘Pera’ sweet orange fruits. The embryos were removed from 30-40-mm wide fruits and inoculated on the MS medium, supplemented with 0.3 mg L-1 GA3 and 1 mg L-1 activated charcoal, previously sterilized at 121°C for 20 minutes. The following photoperiods were evaluated: 8, 10, 12, 14, 16, 18, and 24 hours of continuous light in 43 µM.m-2.s-1 intensity, at 27ºC, in B.O.D chambers. The 16 hours continuous light was performed in growth room at 35 µM m-2 s-1. The statistical analysis used was entirely randomized, with four replications, each one constituted of three tubes. After 60 days, better results for plant height, number of leaves, above ground fresh matter weight, root length, and root fresh weight were obtained with 8, 10, 12, 14, 18 e 24 hours photoperiod. The 16 hours rendered smaller immature embryos development.

En el presente trabajo se evalúa la calidad de fruta y el momento óptimo de recolección de dos grupos de variedades de mandarinas tempranas, Satsumas y Clementinas, sobre citrange Carrizo bajo las condiciones de cultivo del Andévalo de Huelva, más concretamente Río Tinto, con el objeto de determinar su comportamiento agronómico, identificar su interés y transferirlo al sector.

Dada la necesidad de contrastar la adaptación de los nuevos patrones a las diversas condiciones ecológicas y de cultivo, junto a la creciente importancia de la citricultura en Andalucía occidental, se ha realizado un ensayo de `Clemenules´ injertada sobre distintos patrones en una parcela experimental situada en Villanueva de los Castillejos (Huelva), con el objetivo de modernizar y mejorar la competitividad del sector. Para ello, se ha procedido a la identificación y caracterización de nuevos patrones de interés en base a las propiedades inducidas sobre el cultivo.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:00:54Z No. of bitstreams: 1 S0103-90162001000300008.pdf: 27782 bytes, checksum: 0344e9e962e933eccc46d353d6286d3b (MD5) Made available in DSpace on 2013-08-22T19:00:54Z (GMT). No. of bitstreams: 1 S0103-90162001000300008.pdf: 27782 bytes, checksum: 0344e9e962e933eccc46d353d6286d3b (MD5) Previous issue date: 2001-09-01 Made available in DSpace on 2013-09-30T20:00:09Z (GMT). No. of bitstreams: 2 S0103-90162001000300008.pdf: 27782 bytes, checksum: 0344e9e962e933eccc46d353d6286d3b (MD5) S0103-90162001000300008.pdf.txt: 17359 bytes, checksum: 7b2c049f32c27e9cc7226ebcf366f227 (MD5) Previous issue date: 2001-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:15:27Z No. of bitstreams: 2 S0103-90162001000300008.pdf: 27782 bytes, checksum: 0344e9e962e933eccc46d353d6286d3b (MD5) S0103-90162001000300008.pdf.txt: 17359 bytes, checksum: 7b2c049f32c27e9cc7226ebcf366f227 (MD5) Made available in DSpace on 2014-05-20T15:15:27Z (GMT). No. of bitstreams: 2 S0103-90162001000300008.pdf: 27782 bytes, checksum: 0344e9e962e933eccc46d353d6286d3b (MD5) S0103-90162001000300008.pdf.txt: 17359 bytes, checksum: 7b2c049f32c27e9cc7226ebcf366f227 (MD5) Previous issue date: 2001-09-01 O tangor 'Murcote' apresenta necessidade de desbaste de frutos devido a alternância de produção, caracterizado por anos de excessiva produção intercalado com anos de baixa produção, evitando assim, a diminuição da qualidade dos frutos. O presente trabalho teve por objetivo avaliar a eficiência de reguladores vegetais, a auxina ANA (ácido naftalenacético) e ethephon (etileno) no desbaste químico de frutos de tangor 'Murcote' aplicado 40 dias após o pleno florescimento. O experimento foi conduzido em Pratânia, SP, onde plantas de 5 anos de idade, enxertadas sobre o limoeiro 'Cravo', foram pulverizadas com ANA a 0, 100, 200, 300 e 400 mg L-1 e com ethephon a 200, 300 e 400 mg L-1, ambos em solução aquosa juntamente com adjuvante não iônico a 0,05%. A contagem dos frutos foi realizada previamente aos tratamentos em 2 ramos marcados por planta. O ANA não interferiu significativamente no desbaste de frutos, com porcentagens de queda variando entre 7 a 14%, enquanto que as pulverizações com ethephon mostraram maior eficiência no desbaste de frutos, principalmente na dose de 400 mg L-1, promovendo 66,6% de queda de frutos, sem contudo induzir a abscisão foliar. As doses inferiores de ethephon também promoveram desbaste de frutos da ordem de 40%. As porcentagens de queda de frutos foram pequenas, para plantas pulverizadas com ANA, enquanto que a aplicação de ethephon promoveu maior eficiência no desbaste de frutos. Alternate bearing is an important caracteristic of some mandarins that reduces fruit quality and yield in tangor Murcott, and to reduce this effect is necessary to perform fruit thinning to avoid high and low production year by year. To evaluate the effects of plant growth regulators on fruit thinning of the 'honey' orange, an auxin (NAA-naphthalene acetic acid) and ethephon (ethylene), were applied 40 days after full bloom in an experiment carried out at Pratania, S.P., Brazil. Five-year-old plants grafted on Rangpur lime were used, sprayed with NAA (0, 100, 200, 300 e 400 mg L-1 and ethephon (200, 300, 400 mg L-1), both in water solution, containing 0.05% of non ionic wetting agent. Fruit number was determined before treatment applications in two shoots per plant. NAA did not promote significant differences on fruit thinning (between 7 to 14 %), however, the application of ethephon, at all rates, increased fruit thinning by 41.6 to 66.6%, with concentrations of 200 to 400 mg L-1 respectively, without leaf drop. Application of NAA did not promote chemical fruit thinning whereas ethephon showed high percentage of fruit thinning after full bloom with increased concentrations. UNESP IB Depto. de Botânica UNESP IB Depto. de Botânica

Two new species of the genus Diachasmimorpha Viereck, 1913 (Braconidae: Opiinae) are described: D. feijeni spec. nov. from Bhutan (reared from Bactrocera minax (Enderlein) (Diptera: Tephritidae) in fruits of Citrus reticulata Blanco (mandarin)) and D. budrysi spec. nov. from Far East Russia. A key to the Palaearctic species is added, including two similar species (Fopius alternatae (Tobias, 1977), and F. myolejae (Tobias, 1977)).

[EN] The juvenile to adult transition (JAT) in higher plants is required for them to reach reproductive competence. However, it is a poorly understood process in woody plants, where only a few genes have been definitely identified as being involved in this transition. This work aims at increasing our understanding of the mechanisms regulating the JAT in citrus. Juvenile and adult plants from Pineapple sweet orange (Citrus sinensis) and Rough lemon (C. jambhiri) were used to screen for differentially expressed transcription factors (TFs) using a 115K microarray developed on the basis of the CitrusTF database. Murcott tangor (C. reticulata C. sinensis) and Duncan grapefruit (C. paradisi) were incorporated into the quantitative real-time reverse transcriptionPCR validation in order to select those genes whose phase-specific regulation was common to the four species. A browsable web database has been created with information about the structural and functional annotation related to 1152 unigenes of putative citrus TFs (CTFs). This database constitutes a valuable resource for research on transcriptional regulation and comparative genomics. Moreover, a microarray has been developed and used that contains these putative CTFs, in order to identify eight genes that showed differential expression in juvenile and adult meristems of four different species of citrus. Those genes have been characterized, and their expression pattern in vegetative and reproductive tissues has been analysed. Four of them are MADS-box genes, a family of TFs involved in developmental processes, whereas another one resembles MADS-box genes but lacks the MADS box itself. The other three showed high partial sequence similarity restricted to specific Arabidopsis protein domains but negligible outside those domains. The work presented here indicates that the JAT in citrus could be controlled by mechanisms that are in part common to those of Arabidopsis, but also somehow different, since specific factors without Arabidopsis orthologues have also been characterized. The potential involvement of the genes in the JAT is discussed., The Bioinformatics Core Service of the IBMCP (UPV-CSIC) is acknowledged for its help in bioinformatic analyses. This work was supported by Conselleria de Agricultura, Pesca y Alimentacion of Generalitat Valenciana [Proy_IVIA09/03] to G.A., and by the Ministry of 'Economia y Competividad'-Fondo Europeo de Desarrollo Regional (FEDER) [AGL2011-26490] and the Ministry of 'Ciencia e Innovacion' [AGL2008-01491] and Prometeo II 2013/008.