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The objective of this work was to estimate the genetic parameters and to evaluate the genotypic diversity of 12 'Tahiti' acid lime (Citrus latifolia) genotypes grafted onto two rootstocks. The experiment was carried out from July 2017 to January 2019, in the municipality of São Mateus, in the state of Espírito Santo, Brazil. Vegetative (stem diameter, canopy projection diameter, and plant height), productive (yield and fruit number), and fruit quality (fruit diameter, soluble solids content, and juice yield) traits were determined. A mixed model was used to estimate heritability and repeatability coefficients, as well as to predict clonal values. Scion diversity was determined through the standardized mean difference of Euclidean distances, and genotypes were clustered by modified Tocher. Clustering quality and trait importance were evaluated using the principal component analysis (PCA). Genotypic variance was observed, which is indicative of the possibility of selection of superior genotypes. The Tocher method showed the presence of three clusters, which is in alignment with the PCA results. The multivariate analyses allows of the selection and the recommendation of superior 'Tahiti' acid lime genotypes. Resumo O objetivo deste trabalho foi estimar os parâmetros genéticos e avaliar a diversidade genética de 12 genótipos de lima ácida 'Tahiti' (Citrus latifolia) enxertados em dois porta-enxertos. O experimento foi conduzido de julho de 2017 a janeiro de 2019, no município de São Mateus, no estado de Espírito Santo, Brasil. Foram mensuradas características vegetativas (diâmetro de caule, diâmetro de projeção de copa e altura de planta), produtivas (rendimento e número de frutos) e de qualidade de frutos (diâmetros de fruto, teor de sólidos solúveis e rendimento de suco). Utilizou-se modelo misto para estimar os coeficientes de herdabilidade e repetibilidade, bem como predizer os valores genéticos. A diversidade entre os enxertos foi obtida por meio da diferença da distância euclidiana média padronizada, e os genótipos foram agrupados pelo método de Tocher modificado. A qualidade do agrupamento e a importância dos caracteres foi avaliada pela análise de componentes principais (ACP). Observou-se variabilidade genética, o que indica a possibilidade de seleção de genótipos superiores. O método de Tocher mostrou a presença de três grupos de genótipos, o que foi congruente com os resultados da ACP. O uso de técnicas multivariadas permite a seleção e a recomendação de genótipos superiores de lima ácida 'Tahiti'.

Persian lime is economically important for Mexico. However, the disease known as Huanglongbing (HLB) causes chlorosis symptoms in the foliage that affect the growth and decreases the yield of the trees. The expression of chlorosis symptoms is associated with starch accumulation and inhibition of antioxidant activity. The objective of the present work was to determine the effect of the application of three resistance elicitors on the expression of three antioxidant genes and on starch and chlorophyll content in Persian lime trees with HLB. Salicylic acid (SA), jasmonic acid (JA) or gamma-aminobutyric acid (GABA) were applied every eight days for nine weeks using a completely randomized design and a one-way ANOVA was performed for the analysis. Expression of APX, CAT and SOD genes was quantified at week nine at four different times. Starch and total chlorophyll content was estimated every three weeks by spectrophotometric methods. The application of the elicitors significantly increased the expression of the three genes, with SA and GABA generating the greatest increase at different times of application. No difference was found in starch and total chlorophyll content at most of the times evaluated. The use of resistance elicitors is promising in the management of HLB in plots already infected, seeking to extend the productive life of the orchards and thus counteract the economic losses caused by HLB.

Energy and water dynamics are crucial for citrus development in the Eastern Amazon. This study aimed to determine the energy balance, water demand, and crop coefficient of acid lime in the northeast region of Pará. A micrometeorological tower was installed in the center of the experimental area to monitor meteorological variables between October 2020 and December 2021. The energy balance and water demand were obtained by the Bowen ratio method. Kc was determined by the ratio between crop and reference evapotranspiration. The results obtained indicate that 63% of the available energy was used by latent heat in the rainiest period, while 60% was used during the less rainy period. Sensible heat used 32% and 34% during the most and least rainy periods, respectively. Soil heat presented a low variation, with an average of 5% for the entire period. Water consumption of the acid lime during the experiment was 1599 mm, with a daily mean of 3.70 mm day−1, while the mean value of Kc was 1.4. These results allow for the design of adequate water supply protocols for the crop in the main citrus pole in the Amazon region.

El Limón Persa (Citrus latifolia) es una especie atractiva a los productores e inversionistas panameños. La Diversidad Genética de 16 clones de Limón Persa procedentes de dos viveros oficiales; 11 del Ministerio de Desarrollo Agropecuario (MIDA) y 5 del Instituto de Innovación Agropecuaria de Panamá (IDIAP) fue estimada mediante marcadores moleculares Inter Simple Sequence Repeats (ISSR) en el Laboratorio de Biología Molecular de la Facultad de Ciencias Agropecuarias de la Universidad de Panamá. Se seleccionaron 13 de 17 cebadores ISSR evaluados que generaron 30 bandas polimórficas. Se utilizó el Programa Computacional PopGene® para la generación de los resultados. Los resultados reflejaron existencia de 3 duplicados entre las 11 muestras evaluadas procedentes de Divisa y que 2 de las 5 muestras provenientes de Rio Hato se encuentran también establecidas en Divisa con identificaciones diferentes. No se encontraron duplicados dentro de las muestras de Rio Hato. Se concluye las muestras de Divisa (1 y 4) (8 y 10) y (3 y 6) son los mismos genotipos. Igualmente se pudo determinar que las muestras; Divisa 9 y Rio Hato 13, aunque tienen diferente identificación, en realidad son las mismas. Situación que se repite con las muestras Divisa 11 y Rio Hato 12.

The citrus juice industry produces a significant amount of peel residues; it can represent between 18 and 30% of the total weight of the fruit. In recent years, there has been an increase in its use as a source of fiber. The objective of this study was to evaluate the Tahiti lemon peel flour (Citrus latifolia Tanaka) as a fat mimetic (10, 20 and 30%) in a cake. The chemical and nutritional characterization of the lemon peel, the determination of the drying conditions to obtain the flour of the lemon peel, and the physical, chemical, and nutritional characterization of the lemon peel flour and cake was evaluated. A high content of dietary fiber for Tahiti lemon peel (89.15 ± 0.00 g/100 g) and flour (85.30 ± 0.06 g/100 g) was obtained. For the drying conditions to obtain the lemon peel flour, a temperature of 60 °C during 16 h was selected. The cake with greater acceptability had a 10% fat replacement with lemon peel flour, which presented a reduction of 19.16% in the fat content and an approximately double increase in the dietary fiber content. This study suggests that the flour obtained from Tahiti lemon flavedo can be used as a mimetic of fat in cakes, contributing to the nutritional characteristics of the food in which it is included.

Citrus plants presenting the typical huanglongbing (HLB) symptoms have been associated to 16SrIX phytoplasma in the States of Sao Paulo (SP), Minas Gerais (MG), Bahia (BA) and, more recently, Distrito Federal (DF), Brazil. Although in SP and MG states ‘Candidatus Liberibacter asiaticus’ is more commonly associated with HLB, single infection by phytoplasmas also occurs. To date, only 16SrIX phytoplasma induces HLB symptoms in BA and DF, a region free of ‘Ca. Liberibacter spp.’. The objective of this work was to survey for alternative hosts and potential vectors of the 16SrIX phytoplasma in citrus orchards from DF using quantitative real-time PCR (qPCR) detection. Fifty-three specimens encompassing fifteen species of weeds were collected from three Tahiti lime (Citrus latifolia Tanaka) and Ponkan mandarin (Citrus reticulata Blanco) orchards. Only five plants, one Euphorbia sp., one Sida sp., and three Bidens pilosa were positive for the presence of the 16SrIX phytoplasma. Regarding the leafhoppers, 16SrIX phytoplasma was detected in 11/ 38 specimens of Scaphytopius sp. and not detected in 32 specimens of Planicephalus flavicosta. These results suggest that spontaneous vegetation and the leafhoppers Scaphytopius may harbor 16SrIX phytoplasma that can further infect citrus orchards. The capacity of Scaphytopius insects to vector the phytoplasma to citrus plant should be better investigated.

Citrus latifolia is increasingly being cultivated in Mediterranean areas, where the need for precise irrigation implies a sound knowledge of the crop's water requirements, which is carried out by monitoring the tree water status in the plant-soil-atmosphere system. Two year-old lime trees (Citrus latifolia Tan. cv. Bearss) were cultivated in 45 L weighing pot-lysimeters filled with a clay-loam soil and equipped with soil water sensors for recording the real-time soil water status. Irrigation, drainage, pot weight, and agro-meteorological variables were also recorded in real-time. Plant water relations - stem (Ψ) and leaf (Ψ) water potentials, and leaf gas exchange - were periodically measured throughout the experiment. The automated irrigation protocol based on the volumetric soil water content was set to prevent tree water stress (with mean seasonal values of Ψ above -0.8 MPa and 7 μmol m s and 80 mmol m s, for net phtosynthesis and stomatal conductance, respectively). From the soil water pot balance, the computed fortnightly ET mean values throughout the growing season varied from 0.25 to 2.56 L plant day in winter and summer months, respectively. Maximum ET values occurred in July when evaporative demand was highest and lime fruits were in their most active growing phase. For day length, lime tree biomass changes were negligible, and the pot tree weight variations served for ET water balance validation (r=0.92***). The contribution of this work is that it establishes a scalable weighing lysimeter prototype for determining the ET of lime trees grown in Mediterranean semi-arid conditions, using real-time soil water balance monitoring managed by an irrigation automation protocol. This approach could be replicated for precise ET measurements in other crops., This research was supported by Spanish National Plan-FEDER-UE-AGL2016-77282-C03-1 R and PID2019-106226RB-C2 1/AEI/10.13039/ 501100011033, and Seneca Foundation of Region of Murcia (19903/ GERM/15) projects. Conesa M.R. acknowledges the postdoctoral financial support received from the Spanish Juan de la Cierva program (FJCI -2017 -32045)

The aim of this study was to evaluate the physiological response and quality of the ‘Tahiti’ acid lime coated with carboxymethylcellulose (N-CMC), pectin (N-PEC) and starch (N-ST) nanocomposites based on cellulose nanocrystals (NC). Respiratory rate, ethylene production, loss of fresh weight, total chlorophyll and fruit firmness were evaluated during 9 days of storage. At the end of storage, only fruits coated with N-CMC and N-PEC exhibited significantly lower ethylene yield (0.92 and 0.98 μg C2H4 kg-1 h-1, respectively) than fruits coated with CMC and PEC (1.6 and 2.02 μg C2H4 kg-1 h-1, respectively). On the 3rd day of storage, fruits coated with N-PEC showed a respiratory rate (12.01 mg CO2 kg-1 h-1) similar to the fruits of the control (13.52 mg CO2 kg-1 h-1), but it was significantly lower than the fruits coated with PEC (14.93 mg CO2 kg-1 h-1). Only fruits coated with N-PEC showed significantly lower fresh weight losses than the control fruits. Fruits coated with N-PEC had chlorophyll retention levels (18.95 mg g-1) higher than fruits with PEC (13.25 mg g-1). This work showed that the N-PEC nanocomposite, based on NC, was the coating that showed greater potential for preserving quality of the ‘Tahiti’ acid lime.

The management of soil cover plants (intercropping) in orchards can contribute to increase productivity of citrus trees. Thus, the present research aimed to evaluate different planting systems for Tahiti acid lime grafted onto Flying Dragon trifoliate orange, a dwarfing rootstock, at high planting density (1,157 trees ha-1). The study was set up in four tillage systems, using Urochloa ruziziensis as an intercrop species in the orchard, and conducted for five years: no-tillage (NT), no-tillage and no-herbicide (NT-NH), minimum tillage (MT) and conventional tillage (CT; without intercropping). Dry matter (DM) production of biomass in the row and interrow of the orchard was evaluated yearly, as well as weed density, soil physical and chemical characteristics, plant water and nutritional status, and fruit yield of trees. Greater deposition of DM of biomass was observed in the row of citrus planting for treatments NT and NT-NH compared to CT and MT treatments, which led to reduced undesirable weed populations. The NT treatment also provided increases of 79% in potassium (K) nutrient concentrations in the leaves of trees and 60% in exchangeable K in the soil surface layer, in the first two years evaluated. The maintenance of the Urochloa ruziensis mulch in the NT system also provided higher soil volumetric moisture content and consequently lower soil resistance penetration and water stress on trees, evidenced by the predawn plant leaf water potential (

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is the most serious threat to the global citrus industry, and its management has depended mainly on the application of chemical insecticides. The application of plant elicitors can contribute to the insect management and also enhance plant physiology. A set of three different experiments was carried out to evaluate the efficacy of foliar applications of synthetic elicitors [salicylic acid (SA), brassinosteroids (Br), chitosan, or thiamine] on the population dynamics of D. citri and their effects on the physiology of Tahiti lime trees. The treatments were as follows: trees were sprayed separately with thiamine, SA, or chitosan at a dose of 100 ppm, respectively; trees were treated with foliar brassinosteroid applications at a dose of 1 ppm; and untreated trees (control). By the end of the experiment, the elicitors reduced (75%) the number of adult psyllids compared with the control, where trees treated with chitosan had ≈0.5 adult individuals accumulated per flush shoot, whereas the control showed around two individuals. Salicylic acid and thiamine also reduced the number of nymphs compared with the control in the 4 weeks after treatment (WAT) (5.5 vs. 10.08 nymphs, respectively). Treatment with synthetic elicitors also caused a 30% reduction in oviposition by D. citri. The foliar applications with Br promoted a greater relative growth rate (RGR) (44 mm·cm−1·d−1) compared with the control treatment and chitosan (24 and 26 mm·cm−1·d−1, respectively). Chitosan sprays favored proline synthesis in both flush shoots and leaves. These results suggest that the use of synthetic elicitors can be considered as a tool to reduce the number of applications of chemical insecticides and decrease the development of resistances by D. citri because these synthetic elicitors showed an efficacy between 40% and 60% in all its stages in field conditions.

The Tahiti acid lime [Citrus latifolia (Yu Tanaka) Tanaka] is one of the citrus species with production potential for domestic consumption and export in the Eastern plains of Colombia. With purpose to evaluate the effects of the use of agricultural gypsum on the chemical properties, absorption of nutrients and production of fruits of Tahiti lime, was carried an experiment in an Oxisol soil of high terrace of the Llanero Foothills. The treatments consisted of five levels of gypsum (0.5 - 1.0 - 1.5 - 2.0 and 2.5 t ha-1). Was used a design random complete block with four repetitions. The fruit production was evaluated during five consecutive years and in the sixth year; the soil chemical analysis and foliar analysis were carried. A positive effect was found on the increase in the content and distribution of Ca, Mg, and S in the soil profile, decrease in interchangeable acidity and increase in pH with the increasing applications of agricultural gypsum. The gypsum applications increased the absorption of Ca and S and reduced the foliar levels of N, K, Mg and Zn, unchanged the productivity of the crop. The highest accumulated fruit production (141.41 t ha-1) was obtained with the application of 2.5 t ha-1 of gypsum. The positive effects of the agricultural gypsum in the distribution of bases in the soil, in the reduction of the acidity and the increase of the pH in depth were demonstrated, improving the productivity of Tahiti lime.

The main purpose of the present study was to characterize the juice and rind of the Persian lime (Citrus latifolia) with different quality of samples, by means of the Photoacoustic Spectroscopy (PAS) technique. In agreement to the Mexican quality standards, the samples under study were classified into four degrees of quality i.e. Extra, Second, Third and Waste classes. We have used PAS to characterize the optical properties of each one of the samples. Thus, we have obtained the absorption spectra of the juice as well as in that part of the rind called flavedo. After that, using another different photoacoustic configuration, we have measured the water vapor permeability of the albedo; i.e. the innermost, white and spongy layer of the rind. Our results show that PAS is a reliable technique to get the grading quality of samples in situ of fresh fruits such as Persian limes by means of the study of some of their physical properties.

Mutual adulterations of lemon and lime juices may be detected using coumarins and psoralens as markers. Poor manufacturing practices or legal but mechanically intense processing of lemons were recently suspected to lead to false accusations of deliberate adulterations with lime juices due to potentially unspecific markers. Therefore, we studied coumarin and psoralen profiles in carefully dissected flavedo, albedo, and endocarp of lime and lemon as well as in juices produced under variable mechanical stresses at laboratory and pilot plant scale. Although the marker herniarin was detectable in juices from lime and harshly extracted lemons at low levels, isopimpinellin, bergapten and the herein proposed, tentatively assigned 5-geranyloxy-8-methoxypsoralen represented unambiguously lime-specific markers. Coumarin and psoralen data also allowed differentiating juices produced at differing degrees of mechanical stress. The latter was also possible using quantitative 1H-NMR spectroscopy, which yielded best results when combined with HPLC data on coumarins and psoralens. In the future, the reported approach may be used for establishing a robust database prior to being used in industrial practice.

International commerce of Persian limes (Citrus latifolia Tanaka) has grown in recent years. Peel color is the most important quality parameter together with juice content and a good balance between TA and TSS. The rootstock's performance determines the characteristics of the fruit in the environmental conditions where it is established. Consequently, to meet the requirements of the Persian lime fruit market, it is important to know the effects of the rootstock, environmental conditions, and its role in the quality of the fruit. To achieve this aim, Persian lime was grafted onto six rootstocks established in three locations with different environmental conditions and fruit quality parameters were evaluated. Results show that the environmental conditions strongly affect the quantity of juice content, as well as TA and TSS, whereas rootstocks influence TSS, and TA. The rootstock's interaction with environmental conditions determined the firmness, and all color parameters evaluated. The study concluded that Persian limes produced under the conditions evaluated led to better fruit quality, fulfilling all the market requirements and desirable traits such as high TSS and TA content and greener fruits.

In this paper a shoot multiplication is described for Citrus latifolia Tan. (persian lime) using nodal segment explants of young one – old – year trees by two different pathways contain with and without callusing phase. The best result for multiple shoot formation and regenerated shoot formation was 3.2 and 2.6 shoots per explants with 4.44 µM BA plus 0.053 µM NAA and 4.44 µM BA plus 0.049 µM IBA respectively. Alike shoot regeneration, shoot elongation was occurred in medium with 4.44 µM BA and 0.049 µM IBA. Micropropagated and regenerated plants are under other experiments.

The maintenance of laboratory confined bees is a growing need for several entomological studies. Improving laboratory conditions, e.g., diet, to allow greater longevity to individuals is a desirable outcome for insects maintained under those conditions. We evaluated the life span of confined Africanized bee “workers” fed with an aqueous solution obtained from acidic hydrolysis of sucrose. We ran two experiments simultaneously and had a single control treatment. In the first one, the bees were fed 100 g of sucrose solution (1:1) enhanced with 0.1, 0.16, 0.3, 0.5 and 0.7 g of citric acid. The second experiment was conducted using an aqueous solution of granulated (1:1) enriched with 1.0, 5.0, 10.0, 15.0 and 20.0 ml of lemon juice from Citrus aurantifolia (C.) Swingle, Citrus latifolia Tanaka and Citrus limonia (L.) Osbeck at in each solution. We arranged ten repetitions with ten bees each. The number of surviving bees was counted every 12 h, during daytime, for 192 h total. The survival curve was adjusted u...

The distribution, incidence and severity damage caused by the dieback complex ( Lasiodiplodia spp.) in Persian lime ( Citrus latifolia ) was determined in 46 orchards of six average years old, 25 trees per orchard in the municipalities of Amacuzac, Ayala, Coatlan del Rio, Cuautla, Jantetelco, Jonacatepec, Puente de Ixtla, Tepalcingo and Tlaltizapan of Zapata, Morelos State, Mexico. Incidence was evaluated according to the number of plants having symptoms of dieback. There were four levels of severity, where 0= healthy tree, 1= gum exudation, 2= cracking with exposure of internal tissue and 3= well-defined canker and branch dieback. Which were transformed to a percentage of means of a scale of three levels of severity, transforming to a percentage of infection using the Townsend and Heuberger equation. Data were analyzed trough the Kruskal Wallis test and Tukey (?=0.05) and p

Glyphosate is a cheap herbicide that has been used to control a wide range of weeds (4&ndash, 6 times/year) in citrus groves of the Gulf of Mexico, however, its excessive use has selected for glyphosate-resistant weeds. We evaluated the efficacy and economic viability of 13 herbicide treatments (glyphosate combined with PRE- and/or POST-emergence herbicides and other alternative treatments), applied in tank-mixture or sequence, to control glyphosate-resistant weeds in two Persian lime groves (referred to as SM-I and SM-II) of the municipality of Acateno, Puebla, during two years (2014 and 2015). The SM-I and SM-II fields had 243 and 346 weeds/m2, respectively, composed mainly of Bidens pilosa and Leptochloa virgata. Echinochloa colona was also frequent in SM-II. The glyphosate alone treatments (1080, 1440, or 1800 g ae ha&minus, 1) presented control levels of the total weed population ranging from 64% to 85% at 15, 30, and 45 d after treatment (DAT) in both fields. Mixtures of glyphosate with grass herbicides such as fluazifop-p-butyl, sethoxydim, and clethodim efficiently controlled E. colona and L. virgata, but favored the regrowth of B. pilosa. The sequential applications of glyphosate + (bromacil + diuron) and glufosinate + oxyfluorfen controlled more than 85% the total weed community for more than 75 days. However, these treatments were between 360% and 390% more expensive (1.79 and 1.89 $/day ha&minus, 1 of satisfactory weed control, respectively), compared to the representative treatment (glyphosate 1080 g ae ha&minus, 1 = USD $29.0 ha&minus, 1). In practical and economic terms, glufosinate alone was the best treatment controlling glyphosate resistant weeds maintaining control levels &gt, 80% for at least 60 DAT ($1.35/day ha&minus, 1). The rest of the treatments, applied in tank-mix or in sequence with glyphosate, had similar or lower control levels (~70%) than glyphosate at 1080 g ae ha&minus, 1. The adoption of glufosiante alone, glufosinate + oxyfluorfen or glyphosate + (bromacil + diuron) must consider the cost of satisfactory weed control per day, the period of weed control, as well as other factors associated with production costs to obtain an integrated weed management in the short and long term.

Citrus peel essential oil has considerable potential to be used as a direct agent against a wide range of Gram-positive and Gram-negative bacteria. The three citrus peel species used in this study included Citrus aurantifolia, Citrus latifolia, and Citrus hystrix. Essential oils were extracted on a pilot model and analyzed by gas chromatography-mass spectrometry (GC-MS). Gram-positive bacteria (Bacillus subilits, Listeria monocytogenes, Staphylococcus aureus) and gram-negative (Escherichia coli, Samonella typhimurium, Pseudomonas aeruginosa) were used to counteract the antibacterial effects of the samples. The yield of hydrodistillation distilled essential oil is C aurantifolia (1.15%), C latifolia (1.32%), and C hystrix (3.18%). The essential oil contains the main ingredient D-Limonene. The highest antibacterial activity against L. monocytogenes is Citrus latifolia essential oil. The main chemical composition of essential oils are β-pinene, D-limonene, γ-terpinene, terpinolene, α-terpineol, … and the antimicrobial activity of the essential oil is affected by the variation of D-limonene. and β-pinene in essential oils.

In this study, the specific chemical composition of Seedless Lemon (Citrus latifolia) grown in Hau Giang Province, Vietnam was determined. The experiment was conducted based on the baseline methods referenced from previous studies. The results of the component survey show that, in Persian Lime, the acidity is 0.637 ± 0.08 g/L and 4.916 ± 0.03 g/L respectively with lemon peel and lemon juice (pH is 4.5 and 2 respectively). The basic components are also determined with the parameters corresponding to lemon peel and lemon juice including: Brix 2% and 8%, ash 1,780 ± 0.004% and 0.314 ± 0.002%, lipid content 2.93 ± 0.044% and 0.542 ± 0.051%. In which, the content of vitamin C in lemon juice is quite good, reaching 8.392 ± 0.28 mg/g. This research helps shape the basic parameters of local Vietnamese raw materials, thereby laying the premise for the development of related products.

The essential oils (EOs) was extracted from Persian lime (Citrus latifolia) peels collected in Hau Giang province, Vietnam. Volatile compositions of EOs obtained by three extraction methods of hydrodistillation (HD), steam distillation (SD) and microwave extraction (ME) were analyzed and compared. The volatile compounds in EOs were analyzed based on gas chromatography-mass spectrometry (GC-MS). An amount of 3 ml/g, 2.3 ml/g and 4 ml/g of EOs was obtained from HD, SD and ME with twenty-one compounds were identified, accounting for 99% -100% of the total oil content. Limonene, β-pinene, α-pinene, γ-Terpinene, α-citral, β-citral and Sabinene are the major compound in essential oil. However, there were qualitative and quantitative differences between oil samples obtained by the three extraction methods. The difference is probably due to the influence of different environmental factors and specific characteristics of each extraction method. The results of this study will provide information on the content and chemical composition of Lemon peels. C. latifolia and serve as a stepping stone for further research into the applications of the compound to cosmetic, food and pharmaceutical products.

En el departamento del Tolima se observan árboles afectados por una fisiopatía que induce muerte de estructuras en individuos de aproximadamente 4 años de edad. Una situación similar fue reportada para Estados Unidos y México, asociado a una fisiopatía, denominada Wood Pocket. Se asumió como causa principal la susceptibilidad del material, dado que en California (EE.UU.) el problema se solucionó con el uso de patrones resistentes. En la zona de estudio aún no se analiza la influencia de los porta-injertos. La literatura reporta que esta fisiopatía, o desorden fisiológico, se potencia en clima cálido seco. La zona de estudio no sólo presenta condiciones de altas temperaturas y de desbalance hídrico, sino además de altas velocidades de infiltración en el suelo. Los factores anteriores conllevan a que las plantas tengan baja disponibilidad de agua para suplir la alta demanda atmosférica, encontrándose típicamente en déficit durante toda la época productiva. Las malas prácticas agrícolas en el manejo hídrico de los huertos, inadecuada aplicación del riego hace que el problema se intensifique. La fisiopatía es una condición generalizada de los huertos de la zona más cálida del Tolima, por lo cual fue necesario identificar las características edafo-climáticas, que benefician o potencian el desarrollo del problema. Los resultados y las recomendaciones de manejo permitirán a los productores generar programas de manejo en zonas afectadas y llegar a prevenir el desorden, donde aún no se presenta.

Citrus fruits possess a high content of phenolic compounds; however, few studies have focused on the changes occurring during fruit growth. In this study, the changes in the concentration of 20 flavonoids, 4 phenolic acids, and their biosynthetic precursors phenylalanine and tyrosine have been evaluated during fruit maturation (14 weeks). Extracts from all samples, obtained by ultrasound assistance, were analyzed by liquid chromatography coupled to tandem mass spectrometry with a triple quad system (LC-QqQ MS/MS). In general, the concentration of flavanones, which represented over 70% of the studied phenols, and flavones increased during fruit growth, reaching their maximum concentration around week 12. In general, flavanols and phenolic acids exhibited their maximum concentration at week 5 and then decreasing significantly during the rest of maturation. Phenylalanine and tyrosine showed a sinuous behavior during fruit growth. Partial least-squares showed a clear differentiation among fruits belonging to different maturation stages, coumaric acid derivatives being the most influential variables on the projection.

Mexico produces the three most important types of lime: Mexican, Persian, andItalian. Persian lime (Citrus latifolia) is the second most important in planted area.Forty-six percent of the production is intended for export. The objective of thisresearch was to analyze the Persian lime value network of the packing andexporting companies. It was conducted at the main Persian lime producing area,located in the central coastal region of the Gulf of Mexico. As an average, thesampled companies were using 55% of their packing capacity. Most of them (83%)work all year long. They have been from 6 to 15 years in operation. Theyemployed a mean of 41 people, thus they are medium-size enterprises. Fourteenactors were complementing their business in production and marketing. Therelationship between packers and the small lime producing farmers was veryinequitable. Low prices were common for Persian lime producers.The fruits theywere packing came mainly from local producers (90%).Their main exportdestinations were: United States, Europe, Canada, and Japan. Other regions areincreasing Persian lime production, threatening the marketing of the farmers of thecentral coast of the Gulf of Mexico.

Asian citrus psyllid, Diaphorina citri Kuwayama, is the vector of “Huanglongbing” disease. Different insecticides are used to control the vector by a government containment program to prevent dissemination of disease in citrus growing areas in Mexico. Increased selection pressure on field populations can result in resistance to insecticides. The goal of this study was to determine susceptibility baselines in a laboratory strain of Asian citrus psyllid susceptible to 11 insecticides from five toxicological groups and determine diagnostic doses to test in eight populations from Tahiti lime, Citrus latifolia Tan., and Mexican lime, Citrus aurantifolia Swingle, orchards with different patterns of insecticide use. Resistance ratios were calculated in comparison with data from a susceptible strain in a laboratory in Florida. Most calculated LD50 and LD95 values corresponded well with mortalities caused by diagnostic doses. Asian citrus psyllids from Apatzingan, Michoacan were very resistant to imidacl...

The inadequate management of ‘Tahiti’ acid lime harvesting has led to quality loss and reduced profitability for producers and exporters. This study evaluated the quality and conservation of ‘Tahiti’ acid limes for export using four different harvesting systems. Fruit were harvested with scissors, by twisting, with the help of a metal basket and with a hook. After harvesting, the fruit were processed and stored at 9 ± 2 °C and 75 ± 5% relative humidity (RH) for 30 d, simulating the conditions of export in refrigerated containers. The fruit were then transferred to 22 ± 2 °C and 75 ± 5% RH for 30 d, according to the commercialization conditions for the fruit. Harvesting with scissors led to a greater conservation of fresh mass, color and peel chlorophyll content of fruit compared with the use of a hook for harvesting. The levels of soluble solids, titratable acidity and ascorbic acid were not influenced by the harvesting system. Fruit harvested with a hook had a higher percentage of oleocellosis and a 30% reduction in the marketable amount compared with fruit harvested by scissors. Mechanical injuries caused during harvest also led to changes in the flavor and aroma of the ‘Tahiti’ acid limes. The results suggest that the physical damage incurred during harvesting prevents the postharvest treatments of ‘Tahiti’ acid limes from providing the expected response with regard to the maintenance of fruit quality and conservation.

Huanglongbing (HLB), considered one of the most lethal diseases of citrus worldwide, has reached the main areas of Mexican lime (Citrus latifolia Tanaka) fruit production on the Pacific coast of Mexico. Growers have initiated intensive use of insecticides in order to control populations of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), the vector of the pathogen, ‘Candidatus Liberibacter asiaticus’ associated with huanglongbing. Presently, costs of insecticides and the side effects of their use are major concerns, because they could impair the management strategy against the vector; and thus, ecologically and economically viable alternatives to conventional insecticides are required in the short term. Therefore the goal of this study was to evaluate the pathogenicity of 27 native isolates and 3 strains of entomopathogenic fungi and determine their potential as biological control agents of D. citri by using 2 different bioassay methods. Bioassays were performed under la...

This study aimed to evaluate the postharvest quality evolution of gamma-irradiated ‘Tahiti’ limes. Shiny, olivegreen fruits with coarse skin (56 cm equatorial diameter) harvested in commercial orchars and processed in commercial packing house line were used. In a preliminary assay, fruits harvested in April 2011 were exposed to a gamma radiation range from 0 to 750 Gy. The 250 and 750 Gy doses negatively affected skin quality and pulp of exposed fruits. For this reason, new assays were carried out using lower doses to irradiate fruits harvested in July 2011 (off-season) and January 2012 (regular harvest period). Fruit harvested in both periods were selected and exposed to radiation doses of 0, 50, 100, 150, and 200 Gy. All irradiations occurred at a rate of 0.46 Gy/h. After fruit irradiation, physical and chemical analyses were performed along a 20-day storage period at room temperature (24 ± 1ºC and 80 ± 5% RH). Irradiation of fruits harvested in July 2011 and January 2012 and treated with doses of up to 200 Gy did not affect the ascorbic acid content, but doses > 100 Gy caused skin yellowing of fruits harvested on both periods. Gamma radiation at doses = 50 Gy reduced the total soluble solids content in off-season fruits. Exposure of fruits harvested in the main harvest period to radiation doses = 150 Gy increased weight loss. Irradiation of ‘Tahiti’ limes at doses between 50 Gy and 700 Gy did not preserve postharvest quality during storage at room temperature. RESUMO O presente trabalho objetivou avaliar a qualidade pós-colheita de frutos de lima ácida ‘Tahiti’ irradiados. Frutos colhidos de pomares comerciais com casca rugosa, de cor verde oliva brilhante e diâmetro equatorial médio de 56 mm foram beneficiados em casa de embalagem comercial. Em ensaio preliminar foram irradiados frutos colhidos em abril de 2011 com doses de irradiação entre 0 e 750 Gy. As doses de 250 a 750 Gy afetaram negativamente a qualidade interna e externa dos frutos. Consequentemente foram realizadas novas avaliações com doses menores de radiação para frutos colhidos em julho de 2011 (entressafra) e janeiro de 2012 (safra). Em ambas as datas, os frutos foram selecionados e submetidos às doses de 0, 50, 100, 150 e 200 Gy. Em todas as datas, foi usada taxa de irradiação de 0,46 Gy/hora. Após a irradiação, os frutos foram submetidos a análises físicas e químicas durante 20 dias de armazenamento em temperatura ambiente (24±1ºC e 80±5% UR). Para os frutos colhidos em julho de 2011 e janeiro de 2012 a irradiação em dosagens de até 200 Gy não afetou o teor de ácido ascórbico, porém exposição a doses > 100 Gy causou amarelecimento da casca nos frutos de ambas as colheitas. A irradiação em dose = 50 Gy reduziu o teor de sólidos solúveis dos frutos colhidos na entressafra. Nos frutos da safra, a exposição a doses = 150 Gy aumentou a perda de massa. A irradiação de frutos de lima ácida ‘Tahiti’ com doses de 50 a 750 Gy não conservou os atributos de qualidade durante o armazenamento em temperatura ambiente.

The concentration of the harvest in a period of the year is a great economical problem for growers because of the fall of prices when the offer increases. Winter harvest attains the best prices of the year, but they occur when the trees produce few fruits. With the aim of getting out-of-harvest season, several treatments were applied, including those involving branch pruning and application of urea to the foliage, in two orchards in Veracruz, Mexico, one in Cuitlahuac and another in Tlalixcoyan, during November and December, respectively. In Cuit¬lahuac, branch pruning and foliar application of urea 5 % got 31.5 flowers per square meter, versus 7.6 % of the control, but the number of fruits was similar to the control, as well as fruit weight and total weight of fruits per tree. In Tlalixcoyan, pruning and foliar urea 10 % (T1) showed better results on blooming (118.75 flowers per square meter) than the control (6.5); greater (20.2) number of fruits per square meter than the control (2.33), and the highest values for harvestable fruits.

Eleven combinations of rootstock varieties and grafts were carried out with the purpose of evaluating the effect on number and size of stomata, as well as on the stomatal index. These variables were correlated with the height of “Persian” lime plants. The rootstocks, ‘C32’, ‘C35’, ‘Benton’, ‘Carrizo’, ‘Florida’ and ‘Morton’ citranges, ‘Amblicarpa’ and ‘Cleopatra’ tangerine, ‘Volkamerian’, ‘Flying Dragon’ lemon and ‘Sour’ orange, which was used a control, were evaluated. ‘Persian’ lime leaves are amphistomatic; on the upper face of the leaf, stomas are found only on the midrib. It was found that the rootstocks modified the number of stomata (from 287 to 331 per mm-2); these parameters were higher with ‘Sour’ orange; the stomatal index was superior in ‘Cleopatra’ tangerine (9.86) and the stomata were larger in ‘Carrizo’ citrange (25.89 μm). A lower area of four ‘Persian’ lime leaves of was found on the plants grafted onto ‘Flying Dragon’ (124 cm-2). On 10 rootstocks the height of ‘Persian’ lime plants was above 4.01 m, and crown diameter was more than 3.03 m, but on ‘Flying Dragon’ height and crown diameter were only 2.43 and 2.21 m, respectively. The number of stomas correlated positively with the number of epidermal cells (r= 0.709) and negatively with rootstock stem diameter (r= -0.449).

This study reports for the first time the presence of citrus psorosis virus (CPsV) in Persian lime (Citrus latifolia) orchards from five counties of the Veracruz state, the main producer and exporter of this fruit in Mexico. The disease was detected in 2016 only in plants grafted on non-certified rootstocks: Volkamerian lemon, Sour orange, Swingle, C-35 and Flying Dragon.

Post-harvest decay of citrus fruits is caused by moulds capable of producing mycotoxins with great impact on health. The objective of this study was to determine the effect of pH and temperature in synthesis of mycotoxins and antibiotics in Persian lime pathogenic and mycotoxigenic moulds, and to investigate the diffusion of mycotoxins inside the citrus fruit. As a result, several mycotoxins were identified, such as aflatoxins and fumonisins. In most of the analysed moulds, synthesis of the secondary metabolites was observed on acidic pH at 20 °C; some antibiotics were found as well. Diffusion of A. niger mycotoxins and antibiotics was observed in the interior of the lime fruit, achieving highest concentration in the septa. Knowing the behaviour of these moulds is useful for evaluation of health risk due to mycotoxins and control of pathogenic and mycotoxigenic post-harvest moulds.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:47:59Z No. of bitstreams: 1 S0100-29452009000200020.pdf: 43530 bytes, checksum: 0d8cbc4a5814f6ae7403369b9548fc0f (MD5) Made available in DSpace on 2013-08-22T18:47:59Z (GMT). No. of bitstreams: 1 S0100-29452009000200020.pdf: 43530 bytes, checksum: 0d8cbc4a5814f6ae7403369b9548fc0f (MD5) Previous issue date: 2009-06-01 Made available in DSpace on 2013-09-30T19:37:44Z (GMT). No. of bitstreams: 2 S0100-29452009000200020.pdf: 43530 bytes, checksum: 0d8cbc4a5814f6ae7403369b9548fc0f (MD5) S0100-29452009000200020.pdf.txt: 25922 bytes, checksum: 53ace75b9e90e7ebf7fcabf79d5980bd (MD5) Previous issue date: 2009-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:08Z No. of bitstreams: 2 S0100-29452009000200020.pdf: 43530 bytes, checksum: 0d8cbc4a5814f6ae7403369b9548fc0f (MD5) S0100-29452009000200020.pdf.txt: 25922 bytes, checksum: 53ace75b9e90e7ebf7fcabf79d5980bd (MD5) Made available in DSpace on 2014-05-20T15:10:08Z (GMT). No. of bitstreams: 2 S0100-29452009000200020.pdf: 43530 bytes, checksum: 0d8cbc4a5814f6ae7403369b9548fc0f (MD5) S0100-29452009000200020.pdf.txt: 25922 bytes, checksum: 53ace75b9e90e7ebf7fcabf79d5980bd (MD5) Previous issue date: 2009-06-01 No presente trabalho, avaliou-se a influência de doze porta-enxertos sobre a qualidade dos frutos da lima-ácida 'Tahiti' (Citrus latifolia Tanaka), clone 'IAC-5', amostrados em duas posições nas plantas, em experimento conduzido na Estação de Citricultura de Bebedouro, em um pomar de três anos. O espaçamento utilizado foi de 8.0 x 5.0m. Os porta-enxertos utilizados foram: citrangeiro 'Carrizo' (C. sinensis (L.) Osbeck x Poncirus trifoliata (L.) Raf.); os híbridos 'Cravo' x 'Swingle' (C. limonia Osbeck x P. trifoliata (L.) Raf. x C. paradisi Macf.) e 'Changsha' x 'English Small' (C. sunki Hort. ex Tan. x P. trifoliata Raf.); as tangerineiras 'Sun Chu Sha Kat' (C. reticulata Blanco) e 'Sunki' (C. sunki Hort. ex Tanaka); os limoeiros 'Cravo Limeira' e 'Cravo FCAV' (C. limonia Osbeck); o citrumeleiro 'Swingle' (P. trifoliata Raf. x C. paradisi Macf.), o tangeleiro 'Orlando' (C. reticulata Blanco x C. paradisi Macf.) e os trifoliateiros 'Rubidoux', 'FCAV' e 'Flying Dragon' (Poncirus trifoliata Raf.). Foi utilizado um delineamento em blocos casualizados, com doze tratamentos e seis repetições. Os distintos porta-enxertos induziram diferenças na qualidade dos frutos, entretanto todas as características de qualidade foram consideradas aceitáveis para a variedade, sendo bons substitutos para o limão 'Cravo'. In the present work, the effect of twelve rootstocks on fruit quality of the nucellar clone IAC-5 of 'Tahiti' lime, (Citrus latifolia Tanaka) and the influence of fruit position on tree in fruit quality was evaluated in the Citrus Experimental Station of Bebedouro (EECB), located in the Bebedouro county, state of São Paulo, Brazil. A 8.0 x 5.0m planting frame was utilized. The evaluated rootstocks were: 'Carrizo' citrange (C. sinensis (L.) Osbeck x Poncirus trifoliata (L.) Raf.); the hybrids 'Rangpur' lime x 'Swingle' citrumello (C. limonia Osbeck x P. trifoliata Raf) and 'Changsha' x 'English Small'(C. sunki Hort. ex Tan. x P. trifoliata Raf.); the mandarins 'Sun Chu Sha Kat' (C. reticulata Blanco) and 'Sunki' (C. sunki Hort. ex Tanaka); the 'Rangpur' limes 'Cravo Limeira' and ' Cravo FCAV' (C. limonia Osbeck); the 'Swingle' citrumello (P. trifoliata Raf. x C. paradisi Macf.); the 'Orlando' tangelo (C. reticulata Blanco x C. paradisi Macf.) and the trifoliates cvs. 'Rubidoux', 'FCAV' and 'Flying Dragon' (P. trifoliata Raf.). The experiment was arranged in a randomized block design, with twelve treatments, six replicates and one plant per plot. The rootstocks induced differences in fruit quality; however, all the evaluated quality characteristics were within the values considered as normal and acceptable for the variety, constituting good alternative rootstocks for the 'Rangpur' lime. Additionally, the fruit position in the plant (northeastern or southwestern) had a significant influence on the external fruit color regardless of the rootstock. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Mandioca e Fruticultura Tropical UNESP Departamento de Produção Vegetal USP ESALQ Departamento de Produção Vegetal UNESP Departamento de Produção Vegetal

O Brasil é o maior produtor mundial de citros, com destaque para o Estado de São Paulo, maior produtor nacional. Recentes estudos mostram que a área irrigada de citros em São Paulo tem aumentado significativamente nos últimos anos. Porém, a falta de informações sobre o manejo eficiente da irrigação na cultura de citros é uma das principais dificuldades enfrentadas pelos produtores. Com o intuito de atender a essa necessidade, este trabalho teve como objetivos determinar a evapotranspiração de uma planta adulta de limeira-ácida 'Tahiti' (Citrus latifolia Tan.) e o coeficiente de cultivo (Kc) no período seco (outono-inverno), utilizando a técnica de lisimetria de pesagem. O experimento foi realizado na ESALQ/USP em Piracicaba - SP, em área irrigada por gotejamento, com plantas espaçadas de 7 x 4 m, sendo cada planta atendida por quatro pontos de molhamento no solo, distribuídos de forma equidistantes entre si. Foi realizado o monitoramento climático, utilizando estação meteorológica automatizada, e a determinação da evapotranspiração da cultura por lisímetro de pesagem. Durante o período de estudo, o Kc variou entre 0,82 e 1,18, e a ETc variou entre 1,2 e 5,6. Brazil is the largest world producer of citrus crop, with São Paulo state leading as the largest national producer. Recent studies show that irrigated areas of citrus in the state have been increasing significantly in the last few years. However, lack of information on irrigation management related to this crop is one of the main problems encountered by the farmers. In order to help solve the above problem, the objective of this work was to determine the evapotranspiration of acid lime adult plant variety 'Tahiti' (Citrus latifolia Tan.) and the crop coefficient during dry period (autumn - winter) using a weighing lysimeter technique. The experiment was carried out at ESALQ/USP in Piracicaba - SP, Brazil, in a drip irrigated area with plant spacing of 7 x 4 m. Each plant was supplied with four wetting equidistant emitters. The climatic data was obtained by the use of automated meteorological station and the crop evapotraspiration by the use of a weighting lysimeter. During the study period, Kc varied from 0.82 to 1.18, and Etc varied from 1.20 to 5.6.

The stem heat balance method (HBM) measures sap flow (SF) in plants, and can be used to estimate daily transpiration flow. It is a powerful technique for water relations and irrigation field studies, but it has to be tested in species of particular interest. This paper discusses effectiveness of the HBM to estimate transpiration of young acid lime plants (Citrus latifolia Tan. cv. Tahiti), grafted on citrumelo cv. Swingle (Poncirus trifoliata Raf. x C. paradisi Macf.), in the field using commercial gauges (model SAG10-ws, Dynamax Inc., Huston), in Piracicaba, State of Sao Paulo, Brazil. SF was correlated to transpiration determined by weighing lysimeters and by a steady-state null-balance porometer. The mean ratio between daily values of SF and lysimetric measurements was practically unitary, showing a mean difference of only 0.05%, being the comparisons of values in periods shorter than 24 hours impaired by effect of wind turbulence on lysimeters. The same occurred (mean difference of 0.38%) when SF and canopy transpiration estimated from porometer measurements were compared in 20-min periods, but transpiration tended to exceed SF in periods of higher transpiration and data dispersion was high (r² = 0.48). An analysis of the sources errors of the techniques was done, including the comparison of the daily course of SF and net radiation. Despite of the dispersion of the comparative data between the HBM and the other two techniques, HBM had a good performance, permitting to recommend its use in studies of water relations in young citrus plants under field conditions.

O objetivo desse estudo foi avaliar métodos não-destrutivos para a determinação da área foliar de plantas jovens de lima ácida 'Tahiti'(Citrus latifolia Tan.), em campo. Foram utilizadas informações de variáveis biométricas de 28 plantas jovens (0,07 a 1,44 m²) e imagens digitais da área frontal de cada planta (silhueta de copa). Essas variáveis foram correlacionadas com medidas diretas (contagem total de folhas x área foliar média). Como resultado, foi possível estimar a área foliar total das plantas (AFT) com base na equação: AFT = 88,936 x DI - 1,4017 (R²=0,75), em que DI representa o diâmetro do caule 5 cm abaixo do ponto em que a copa foi enxertada, e a silhueta da planta em m² (IM): AFT = 2,4951 x IM (R²=0,72). A área foliar dos ramos secundários das plantas (AFR) pode ser estimada mediante uma equação exponencial envolvendo o diâmetro do ramo (DR): AFR = 0,0144e277,02 x DR (R²=0,71). Estas metodologias podem ser utilizadas quando o interesse for por um valor médio de área foliar no pomar, não sendo indicadas quando é necessária elevada precisão, pois os erros são elevados.

In this work lime essential oils were extracted by hydrodistillation and supercritical carbon dioxide. In the case of hydrodistillation, the parameters evaluated were extraction time and characteristics of the plant material. In supercritical extraction, the parameters evaluated were temperature, pressure, CO2 flow, extraction time and material characteristics. Considering citral content, the best results for hydrodistillation were obtained with a distillation time of 3 hours using whole peels. The best results for supercritical extraction were found using 60ºC, 90 bar, at a CO2 flow rate of 1 mL/ min for 30 minutes using milled peels. The best yields of lime oil were obtained by hydrodistillation (5.45% w/w) and supercritical extraction (7.93% w/w) for milled peels.Neste trabalho o óleo essencial de lima ácida foi extraído por hidrodestilação e CO2 supercrítico. No caso da hidrodestilação, os parâmetros avaliados foram o tempo de processo e características do material vegetal. Em extração supercrítica, os parâmetros avaliados foram temperatura, pressão e fluxo do CO2, tempo de processo e características do material. Considerando o conteúdo de citral, os melhores resultados para hidrodestilação foram obtidos em um tempo de processo de 3 horas utilizando-se cascas inteiras. Os melhores resultados para extração supercrítica foram obtidos a 60ºC, 90 bar, a um fluxo de CO2 de 1 mL/ min para 30 minutos de processo utilizando-se cascas moídas. Os melhores resultados em termos de rendimento de óleo essencial foram obtidos por hidrodestilação (5,45% p/p) e extração supercrítica (7,93% p/p), para cascas moídas.

The main objective of this work was to investigate the high-pressure phase behavior of the binary systems CO 2 –lemon ( Citrus latifolia Tanaka) and CO 2 –bergamot ( Citrus bergamia Risso et Poit.) peel oils. The static synthetic method using a variable-volume view cell was employed for obtaining the experimental data in the CO 2 overall composition range of 5–98 wt.%, from 313 to 343 K and pressures up to 19 MPa. For both systems, the experimental data revealed the occurrence of vapor–liquid, liquid–liquid and vapor–liquid–liquid phase transitions. Additionally, vapor–liquid equilibrium data were measured for CO 2 –linalyl acetate, one of the major compounds of the bergamot oil. The thermodynamic modeling was performed using the Peng–Robinson equation of state with the classical quadratic mixing rules, with a satisfactory agreement between experimental and calculated values.

The 'Tahiti' lime (Citrus latifolia Tanaka) is an important commercial citrus cultivar in Brazil. 'Rangpur' lime has being used as its main rootstock, but it is susceptible to root rot caused by Phytophthora, reducing tree longevity. An experiment was set up in a randomized block design, with three trees per plot of each rootstock and four replicates, and run for 12 years, aiming to compare the performance of 'IAC-5 Tahiti' lime, budded on 'Rangpur' lime (Citrus limonia Osb.); 'C-13' citrange (Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf.); 'African' rough lemon (Citrus jambhiri Lush.); 'Volkamer' lemon (Citrus volkameriana Ten. & Pasq.); trifoliate orange (Poncirus trifoliata (L.) Raf.); 'Sunki' mandarin (Citrus sunki Hort. ex Tan.) and 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan.). Eleven years after the establishment of the orchard, trees with the greatest canopy development were budded on 'C-13' citrange and 'African' rough lemon, and both differed significantly from trees budded on trifoliate orange, 'Sunki' and 'Cleopatra' mandarins, which presented the smallest canopy development. Trees budded on 'Rangpur' lime and 'C-13' citrange had the highest cumulative yields, and were different from trees budded on trifoliate orange, 'Cleopatra' and 'Sunki' mandarins. There was no rootstock effect on mean fruit weight and on the total soluble solid/acid ratio in the juice. The 'Rangpur' lime and the 'Cleopatra' mandarin rootstocks reduced longevity of plants. A lima ácida 'Tahiti' (Citrus latifolia Tanaka) é uma importante variedade comercial de citros no Brasil e o limão 'Cravo', seu principal porta-enxerto, apresenta suscetibilidade à gomose de Phytophthora, reduzindo a longevidade das plantas. Este experimento foi implantado em blocos ao acaso, contendo sete tratamentos, três plantas por parcela e quatro repetições, e avaliado por 12 anos com o objetivo de comparar o comportamento de plantas de lima ácida 'Tahiti IAC-5', enxertadas em limão 'Cravo' (Citrus limonia Osb.), citrange 'C-13' (Citrus sinensis (L.) Osb. X Poncirus trifoliata (L.) Raf.), limão 'Rugoso da África' (Citrus jambhiri Lush.), limão 'Volkameriano' (Citrus volkameriana Ten. & Pasq.), Trifoliata (Poncirus trifoliata (L.) Raf.), tangerina 'Sunki' (Citrus sunki Hort. ex Tan.) e tangerina 'Cleópatra' (Citrus reshni Hort. ex Tan.). Onze anos após o plantio, as limeiras com maior volume de copa foram aquelas enxertadas em citrange 'C-13' e limão 'Rugoso da África', sendo que ambos diferiram das plantas em Trifoliata, tangerinas 'Sunki' e 'Cleópatra', que mostraram os menores volumes. Plantas enxertadas em limão 'Cravo' e citrange 'C-13' apresentaram as maiores produções acumuladas, com diferença daquelas em Trifoliata e tangerinas 'Sunki' e 'Cleópatra'. Não houve efeito dos porta-enxertos no peso médio dos frutos e na relação sólidos solúveis totais e acidez do suco dos frutos. O limão 'Cravo' e a tangerina 'Cleópatra' induziram baixa longevidade.

SummaryBy using net radiometers mounted on a circular frame rotating around the canopy, measurements of total all-wave radiation absorbed by two ‘Tahiti’ acid lime trees were carried out in an orchard in Piracicaba, Sao Paulo State, Brazil. The rotating system around the canopy of a tree was formerly idealized and used in New Zealand, allowing integration of all-wave radiation and photosynthetically active radiation absorbed. In an experiment in December 1997, a first device using six net radiometers mounted on a light frame was used. A bigger device, more like the one used in New Zealand, in terms of the number of radiometers and the frame, with a different torque system, was used in another tree on some days from July to September 2000. The performance of both devices is discussed, including the possible error sources when using the first model (1997) and the problems of torque transmission on the second. Despite the lack of a test to check the performance of the device and the problems presented in the...