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Blueberry is a kind of new rising popular perennial fruit with high healthful quality. It is of utmost importance to develop new blueberry varieties for different climatic zones to satisfy the demand of people in the world. Molecular marker assisted breeding is believed to be an ideal method for the development of new blueberry varieties for its shorter breeding cycle than the conventional breeding. Simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) markers are widely used molecular tools for marker assisted breeding, which could be detected at large scale by the transcriptome sequencing. Here, we sequenced the leaves transcriptome of 19 rabbiteye (Vaccinium ashei Reade), 13 southern highbush (Vaccinium. corymbosum L × native southern Vaccinium Spp) and 22 cultivars of northern highbush blueberry (Vaccinium corymbosum L) by using next generation sequencing technologies. A total of 80.825 Gb clean data with an average of about 12.525 million reads per cultivar were obtained. We assembled 58,968, 55,973 and 53,887 unigenes by using the clean data from rabbiteye, southern highbush and northern highbush blueberry cultivars, respectively. Among these unigenes, 3599, 3495 and 3513 unigenes were detected as candidate resistance genes in three blueberry crops. Moreover, we identified more than 8756, 9020, and 9198 SSR markers from these unigenes, and 7665, 4861, 13,063 SNPs from the annotated single copy unigenes, respectively. The results will be helpful for the molecular genetics and association analysis of blueberry and the basic molecular information of pest and disease resistance of blueberry, and would also offer huge number of molecular tools for the marker assisted breeding to produce blueberry cultivars with different adaptive characteristics. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the residual characteristics and to calculate the persistence of the fungicides fluxapyroxad (15.3% suspension concentrate) and penthiopyrad (20% emulsifiable concentrate) on the leaves of greenhouse-cultivated perilla (Perilla frutescens var. japonica Hara). Fluxapyroxad was diluted 2,000-fold and penthiopyrad was diluted 4,000-fold. Each solution was sprayed 3 times onto crops at 7-d intervals before harvest. Leaf samples were collected at 3 h (0 d), 1, 3, 5 and 7 d after the third and final treatment. The recovery ranges of fluxapyroxad and penthiopyrad and their metabolites were 74.2%–104.1%. Pesticide residue analyses indicated that fluxapyroxad and penthiopyrad residues in perilla leaves dissipated over time. The persistence of fluxapyroxad and penthiopyrad residues 7 d after the final spray were 50.0% ± 4.9% and 44.2% ± 2.8% of those measured 3 h (0 d) after the final spray, respectively. The percent acceptable daily intake (%ADI)—which was assessed according to the daily food intake by Koreans according to age—was < 7.3%. Therefore, it was determined that the health risk was low. The perception that residual pesticides are present in large amounts in perilla leaf has led to consumer concern. However, in this study, the amounts of pesticide in perilla leaf decreased over time. Although it has been hypothesized that the risk of pesticide intake would be higher in younger children, the results actually suggest the opposite. Therefore, the pesticides in question are considered to be safe for use on perilla leaves. [ABSTRACT FROM AUTHOR]

Washington State growers lose more than $80 million annually to bird damage in fruit crops such as cherries, grapes, Honeycrisp apples, and blueberries. Conventional bird deterrence techniques, such as netting, auditory devices, visual devices, chemical application, falconry, and shooting, are either costly, ineffective, or harmful to birds. At the same time, unmanned aerial systems (UAS) have become popular in military, civilian, and agricultural applications due to decreasing cost, good maneuverability, and their ability to perform multiple types of missions. This article presents an approach using UAS to deter birds and minimize their damage to wine grapes. A quadcopter UAS was flown for three days in September 2016 over a section (30 m × 30 m) of a vineyard to deter birds. The test section of the vineyard was next to a canyon with many trees that provided shelter for a large number of birds. The experimental design included different deterrence methods against birds, including auditory deterrence, visual deterrence, and varying UAS flight patterns. The test section of the vineyard was under continuous video surveillance from 7:00 to 9:00 a.m. using four GoPro cameras for five continuous days, including three days when the UAS was flown. A Gaussian mixture model-based motion detection algorithm was used to detect birds in the videos, a Kalman filter was then used for tracking the detected birds, and bird activities (incoming and outgoing birds) were counted based on the movement of birds across the plot boundary. Two accuracy measures (precision and recall) were calculated to analyze the performance of the automated bird detection and counting system. The results showed that the proposed system achieved a precision of 84% and recall of 87% in counting incoming and outgoing birds. The automated bird counting system was then used to evaluate the performance of the UAS-based bird deterrence system. The results showed that bird activity was more than 300% higher on days with no UAS flights compared to days when the UAS was flown with on-board bird deterrence measures. UAS flights covering the entire experimental plot with auditory deterrence had a better effect than flights with visual deterrence. The results showed the potential for developing an automated bird deterrence system for vineyards and other crops. Extended studies with multi-year, multi-field, and multi-platform experiments are essential to further validate the results. [ABSTRACT FROM AUTHOR]

Horticulturalists and gardeners in temperate regions often claim that planting marigolds next to tomato plants protects the tomatoes from the glasshouse whitefly (Trialeurodes vaporariorum Westwood). If shown to hold true, this technique could be used in larger-scale tomato production, protecting the crop and helping to introduce greater plant diversity into these agro-ecosystems. Here we present two large-scale glasshouse trials corresponding to the two main ways growers are likely to use marigolds to control whiteflies. In the first, marigolds are grown next to tomato throughout the growing period and we quantify whitefly population growth from the seedling stage over a 48 day infestation period. Here we show that association with marigolds significantly slows whitefly population development. Introducing additional whitefly-attractive ‘pull’ plants around the perimeter of plots has little effect, but reducing the proportion of marigolds and introducing other non-hosts of whiteflies (basil, nasturtium and Chinese cabbage) also reduces whitefly populations on tomato. The second experiment assesses the efficacy of marigolds when used as an ‘emergency’ measure. Here we allow whitefly populations to build to a high density on unprotected tomatoes then introduce marigolds and assess whitefly population over a further period. Following laboratory work showing limonene to be a major chemical component of French marigolds and a negative behaviour response of whiteflies to this compound, limonene dispensers are added as an additional treatment to this experiment. “Emergency” marigold companion planting yielded minimal reductions in whitefly performance, but the use of limonene dispensers was more effective. Our work indicates that companion planting short vine tomatoes with French marigolds throughout the growing season will slow development of whitefly populations. Introducing marigolds to unprotected tomatoes after significant whitefly build-up will be less effective. The use of limonene dispensers placed near to tomato plants also shows promise. It is argued that this work supports the possibility of the development of a mixture of tomato companion plants that infer ‘associational resistance’ against many major invertebrate pests of tomato. Such a mixture, if comprising edible or ornamental plants, would be economically viable, would reduce the need for additional chemical and biological control, and, if used outdoors, would generate plant-diverse agro-ecosystems that are better able to harbour invertebrate wildlife. [ABSTRACT FROM AUTHOR]

To fully utilize the characteristic climatic conditions in the southern region of China, a two-crop-a-year cultivation system technique for ‘Kyoho’ grape was developed during the past decade. After summer harvest in June, appropriate pruning and chemical treatments promote flowering and fruiting, which enables a second harvest in late December. Due to climatic differences between the two crop growing seasons, grape phenol and carotenoid metabolism differ greatly. The reported study analyzed the transcriptome of the carotenoid and phenylpropanoid/flavonoid pathways in grapes at four different stages during the two growing seasons. Compared with those in summer grapes, expression levels of the majority of genes involved in the carotenoid metabolic pathway in winter grapes were generally upregulated. This result was associated with lower rainfall and much more abundant sunlight during the second growing season. On the other hand, summer cropping strongly triggered the expression of upstream genes in the phenylpropanoid/flavonoid pathway at E-L 33 and E-L 35. Transcript levels of flavonoid 3’,5’-hydroxylase (F3’5’H), flavonoid 3’-hydroxylase (F3’H), flavonoid 3-hydroxylase (F3H) and glutathione S-transferase (GST) were upregulated in winter grapes at the mature stage. Together, these results might indicate that more flavonoids would be synthesized in ripe winter grapes during the mature stage of the second crop under much drier conditions, longer sunlight hours and lower temperature. These data provide a theoretical foundation for the secondary metabolism of berries grown under two-crop-a-year cultivation systems. [ABSTRACT FROM AUTHOR]

To target food security interventions for smallholder households, decision makers need large-scale information, such as maps on poverty, food security and key livelihood activities. Such information is often based on expert knowledge or aggregated data, despite the fact that food security and poverty are driven largely by processes at the household level. At present, it is unclear if and how household level information can contribute to the spatial prediction of such welfare indicators or to what extent local variability is ignored by current mapping efforts. A combination of geo-referenced household level information with spatially continuous information is an underused approach to quantify local and large-scale variation, while it can provide a direct estimate of the variability of welfare indicators at the most relevant scale. We applied a stepwise regression kriging procedure to translate point information to spatially explicit patterns and create country-wide predictions with associated uncertainty estimates for indicators on food availability and related livelihood activities using household survey data from Uganda. With few exceptions, predictions of the indicators were weak, highlighting the difficulty in capturing variability at larger scale. Household explanatory variables identified little additional variation compared to environmental explanatory variables alone. Spatial predictability was strongest for indicators whose distribution was determined by environmental gradients. In contrast, indicators of crops that were more ubiquitously present across agroecological zones showed large local variation, which often overruled large-scale patterns. Our procedure adds to existing approaches that often only show large-scale patterns by revealing that local variation in welfare is large. Interventions that aim to target the poor must recognise that diversity in livelihood activities for income generation within any given area often overrides the variability of livelihood activities between distant regions in the country. [ABSTRACT FROM AUTHOR]

This study reports the construction of high density linkage maps of Japanese plum (Prunus salicina Lindl.) using single nucleotide polymorphism markers (SNPs), obtained with a GBS strategy. The mapping population (An x Au) was obtained by crossing cv. “Angeleno” (An) as maternal line and cv. “Aurora” (Au) as the pollen donor. A total of 49,826 SNPs were identified using the peach genome V2.1 as a reference. Then a stringent filtering was carried out, which revealed 1,441 high quality SNPs in 137 An x Au offspring, which were mapped in eight linkage groups. Finally, the consensus map was built using 732 SNPs which spanned 617 cM with an average of 0.96 cM between adjacent markers. The majority of the SNPs were distributed in the intragenic region in all the linkage groups. Considering all linkage groups together, 85.6% of the SNPs were located in intragenic regions and only 14.4% were located in intergenic regions. The genetic linkage analysis was able to co-localize two to three SNPs over 37 putative orthologous genes in eight linkage groups in the Japanese plum map. These results indicate a high level of synteny and collinearity between Japanese plum and peach genomes. [ABSTRACT FROM AUTHOR]

The Michurinsk Department of the Vavilov Society of Geneticists and Breeding Scientists (VOGiS) was formed in 1966 after the constituent congress of VOGiS and nowadays includes 54 members. The scientists are engaged in 4 scientific institutions affiliated with FASO of Russia. The paper presents investigations of the individual genetics of leading fruit crops (pear, cherry, apple), identified genes, regularities of inheriting resistance to low temperatures, the most harmful diseases and several characters responsible for fruit quality. Some genes were identified for the first time. These are genes regulating Coccomyces hiemalis Higg. resistance (A), retarded growth habit in cherry (O2), astringency (Ta) and juiciness (Su) of fruit in pear. On the base of hybridological analysis and DNA marking, genotypes were identified. These genotypes carry target alleles of the following genes: columnar growth habit (Co) in apple, dwarf trait (PcDw) in pear, retardant growth (O2) in cherry. It was found that the markers C18470-25831, Mdo.chr 10.12, Co04R12 do not always show robust results for screening of young apple seedlings with columnar growth habit (Co) because they are identified as non-columnar forms. The primer pairs of 29f1 и jwi1r are the most robust ones for identification of columnar genotypes. These primers amplify specific PCR product of 586 bp (5’CR). On the basis of molecular-genetic analysis of apple initial forms and hybrid seedlings, there were identified targeted alleles of monogenic scab resistance genes including dominant homozygous genotype (Rvi6Rvi6) and also alleles of genes involved in the control of the biosynthesis of ethylene (Md-ACS1 and Md-ACO1) and expansin (Md-Exp7) controlling fruit long shelf life and pulp firmness.

The present study aimed at identifying and mapping key genes expressed in root tissues involved in drought and salinity tolerance/resistance conserved among different fruit tree species. Twenty-six RNA-Seq samples were analyzed from six published studies in five plant species (Olea europaea, Vitis riparia Michx, Prunus mahaleb, Prunus persica, Phoenix dactylifera). This meta-analysis used a bioinformatic pipeline identifying 750 genes that were commonly modulated in three salinity studies and 683 genes that were commonly regulated among three drought studies, implying their conserved role in resistance/tolerance/response to these environmental stresses. A comparison was done on the genes that were in common among both salinity and drought resulted in 82 genes, of which 39 were commonly regulated with the same trend of expression (23 were upregulated and 16 were downregulated). Gene set enrichment and pathway analysis pointed out that pathways encoding regulation of defense response, drug transmembrane transport, and metal ion binding are general key molecular responses to these two abiotic stress responses. Furthermore, hormonal molecular crosstalk plays an essential role in the fine-tuning of plant responses to drought and salinity. Drought and salinity induced a different molecular “hormonal fingerprint”. Dehydration stress specifically enhanced multiple genes responsive to abscisic acid, gibberellin, brassinosteroids, and the ethylene-activated signaling pathway. Salt stress mostly repressed genes encoding for key enzymes in signaling proteins in auxin-, gibberellin-(gibberellin 2 oxidase 8), and abscisic acid-related pathways (aldehyde oxidase 4, abscisic acid-responsive element-binding protein 3). Abiotic stress-related genes were mapped into the chromosome to identify molecular markers usable for the improvement of these complex quantitative traits. This meta-analysis identified genes that serve as potential targets to develop cultivars with enhanced drought and salinity resistance and/or tolerance across different fruit tree crops in a biotechnological sustainable way.

Eucalyptus globules belonging to the Myrtaceae family was explored for the synthesis of zinc oxide nanoparticles and for biological applications. The aqueous extract of the synthesized zinc nanoparticles (ZnNPs) was characterized using UV-visible spectrophotometer, FTIR, SEM and TEM. The aqueous broth was observed to be an efficient reducing agent, leading to the rapid formation of ZnNPs of varied shapes with sizes ranging between 52−70 nm. In addition, antifungal activity of the biosynthesized ZnNPs was evaluated against major phytopathogens of apple orchards. At 100 ppm of ZnNPs, the fungal growth inhibition rate was found to be 76.7% for Alternaria mali, followed by 65.4 and 55.2% inhibition rate for Botryosphaeria dothidea and Diplodia seriata, respectively. The microscopic observations of the treated fungal plates revealed that ZnNPs damages the topography of the fungal hyphal layers leading to a reduced contraction of hyphae. This considerable fungicidal property of ZnNPs against phytopathogenic fungi can have a tremendous impact on exploitation of ZnNPs for fungal pest management and ensure protection in fruit crops.

Blueberry is a small fruit crop which includes a complex group of different Vaccinium species of various ploidy levels. Commercial blueberries have been grown in Europe most recently, so there is not much information available about their adaptation into new regions. In this work we investigated adaptation to the environmental conditions of northern Spain, in terms of flowering and ripening seasons, of a set of 70 blueberry cultivars including several of the most important cultivated American species (V. corymbosum, V. virgatum, V. macrocarpon and V. uliginosum) in order to identify which types are best-suited in this geographical area of Europe. Most materials showed high chilling requirements for flowering under local conditions, while materials with low-chilling requirements showed problems in the maturation process of the flowers. Most cultivars were early or mid-season while a relative lack of late-season cultivars was observed. GBS was used for the analysis of genetic diversity in this sample of 70 cultivars. A total of 5255 SNP markers were obtained and a cluster analysis revealed three main groups associated with the ploidy level of the species. A Principal Component Analysis revealed a grouping of the V. corymbosum cultivars according to their chilling requirements. A total of 29 SNPs were identified as being highly informative for diversity analysis and potentially useful for cultivar identification and for breeding purposes. The results obtained from this research should contribute to the expansion of this crop, as well as providing data about genetic diversity useful for the preservation of genetic resources or for future breeding programs. [ABSTRACT FROM AUTHOR]

Shelf life is the time a product can be stored without losing its qualitative characteristics. It represents one of the most critical quality traits for food products, particularly for fleshy fruits, including tomatoes. Tomatoes’ shelf life is usually shortened due to fast over-ripening caused by several different factors, among which changes in temperature, respiration and pathogen exposure. Although tomatoes usually do not contain anthocyanins, varieties enriched in these antioxidant compounds have been recently developed. The anthocyanin-rich tomatoes have been shown to possess a significantly extended shelf life by delayed over-ripening and reduction of the susceptibility to certain pathogens. In the present work, we compared different conditions of postharvest storage of anthocyanin-rich tomato fruits with the aim to understand if the added value represented by the presence of the anthocyanins in the fruit peel can be affected in postharvest. For this purpose we used an anthocyanin-enriched tomato line derived from conventional breeding and took into consideration different light and temperature conditions, known to affect fruit physiology during postharvest as well as anthocyanin production. Several quality traits related to the fruit ripening were measured, including anthocyanin and carotenoid content, pH, titratable acidity and total soluble solids. In this way we identified that the most suitable fruit storage and postharvest anthocyanin accumulation were obtained through exposure to cool temperature (12° C), particularly in the presence of light. Under these parameters, tomato fruits showed increased anthocyanin content and unchanged flavour-related features up to three weeks after harvesting. [ABSTRACT FROM AUTHOR]

The reduction of chemical fungicides in agriculture has led to the use of microorganisms as biocontrol agents. Starmerella bacillaris is a non-Saccharomyces yeast associated with overripe and botrytized grape berries microbiota. Its use has been proposed for wine fermentation because of yeast fructophilic character and high glycerol production. Recently, S. bacillaris has been demonstrated to possess antifungal activity against Botrytis cinerea on the grape. Penicillium expansum is the pathogen responsible for the blue mold rot, the most important postharvest disease of apples. These fruits are the raw material of the cider, an alcoholic beverage commonly produced using S. cerevisiae starter cultures. In this study 14 S. bacillaris strains have been studied to evaluate their postharvest antifungal activity against P. expansum on apples. Moreover, the fermentation performances in apple juice of these non-Saccharomyces strains were tested, both in single-strain fermentation and in sequential fermentation, together with S. cerevisiae. Four S. bacillaris strains, able to significantly decrease blue mold rot symptoms and to increase glycerol content during fermentation have been selected to improve apple and cider quality. [ABSTRACT FROM AUTHOR]

This study was conducted during the 2014 and 2015 vintages on Vitis vinifera L. cv. Merlot and Cabernet Gernischt to investigate whether natural variation in berry size could affect grape aromatic compounds. Grape berries were separated into three size categories based on their diameter: small, middle and large. The results showed that berry size exerted a significant influence on the volatile profiles of both winegrape varieties. Hierarchical clustering analysis demonstrated that the volatile profiles of middle berries were different from those of large and small berries. Middle berries had the greatest abundance of aroma compounds, followed by small and large berries. Especially, C6/C9 compounds, norisoprenoids, terpenoids showed markedly different concentrations among differently sized Merlot berries and C6/C9 compounds, terpenoids among differently sized Cabernet Gernischt berries. Middle berries of both grape varieties may possess the greatest intensity of fresh-green, fruity and floral aromas due to the high odour activity values (OAVs) of decanal, hexanal, (E)-2-hexenal, (E)-β-damascenone and β-ionone in middle sizes of Merlot berries and the high OAVs of (E)-2-hexenal and (E)-β-damascenone in middle sizes of Cabernet Gernischt berries. This knowledge could be important for winemakers to conduct targeted berry sorting, thereby improving the aromatic quality of grapes. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the breeding of citrus (Citrus spp.), suitable fruit quality is essential for consumer acceptance of new cultivars. To identify parental combinations producing F1 progeny with fruit-quality traits exceeding certain selection criteria, we developed a simple and practical method for predicting multiple-trait segregation in an F1 progeny population. This method uses breeding values of parental genotypes and an additive genetic (co)variance matrix calculated by the best linear unbiased prediction method to construct a model for trait segregation in F1 progeny. To confirm the validity of our proposed method, we calculated the breeding values and additive genetic (co)variances based on phenotypic records on nine fruit-quality traits in 2122 genotypes, and constructed a trait segregation model. Subsequently, we applied the trait segregation model to all pairs of the 2122 genotypes (i.e., 2,252,503 combinations), and predicted the most promising combinations and evaluated their probabilities of producing superior genotypes exceeding the nine fruit-quality traits of satsuma mandarin (Citrus unshiu Marcow.) or ‘Shiranuhi’ (‘Kiyomi’ × ‘Nakano No. 3’ ponkan), two popular citrus cultivars in Japan. We consider these results to be useful not only for selecting good parental combinations for fruit quality or other important traits but also for determining the scale of breeding programs required to achieve specific breeding goals. [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid (ACP), Diaphorina citri, is a major vector of the bacteria Candidatus Liberibacter asiaticus and C.L. americanus, which cause Huanglongbing disease (HLB) (aka Citrus greening disease), considered the most serious bacterial disease of citrus trees. As part of a multidisciplinary project on psyllid biology (), the results presented here concern a detailed anatomical study of the male reproductive system (testes, seminal vesicles, accessory glands, sperm pump, connecting ducts, and aedeagus) using micro-computed tomography (micro-CT). The study summarizes current knowledge on psyllids male reproductive system and represents significant advances in the knowledge of ACP anatomy. [ABSTRACT FROM AUTHOR]

The abundance of banana flower thrips (Thrips hawaiiensis Morgan) in a banana (Musa acuminata Colla “Williams” cultivar) plantation was investigated using yellow sticky traps (29.70 cm × 21.00 cm) in 2015. Banana flower thrips occurred throughout the year with monthly variation, and the maximum occurrence was observed in October and November during the bud burst (73.80 ± 6.32 adults/trap) and young fruit (70.06 ± 5.69 adults/trap) periods. The damage rates were as follows: interior flowers >3rd-layer flowers > 2nd-layer flowers > 1st-layer flowers > young fruits. This result indicates that thrips migrated to lower bracts, young fruits, and other flower buds as bracts gradually opened. Results also showed that the reducing sugar, vitamin C, protein and ash contents in thrips-damaged flowers were all significantly lower than those in undamaged flowers, while there was no significant difference between damaged and undamaged young banana fruit. Our results indicated that the abundances of banana flower thrips were closely associated with the growing stage of banana. Thrips mainly infested flower buds and caused a reduction in nutrients for the host plant, especially the reducing sugar and vitamin C contents, which reduced the nutritional quality of banana fruits and the quality of flower bud by-products of banana. [ABSTRACT FROM AUTHOR]

Spring frosts, as experienced in Europe in April 2016 and 2017, pose a considerable risk to agricultural production, with the potential to cause significant damages to agricultural yields. Meteorological blocking events (stable high-pressure systems) have been shown to be one of the factors that trigger cold spells in spring. While current knowledge does not allow for drawing conclusions as to any change in future frequency and duration of blocking episodes due to climate change, the combination of their stable occurrence with the biological system under a warming trend can lead to economic damage increases. To evaluate future frost risk for apple producers in south-eastern Styria, we combine a phenological sequential model with highly resolved climate projections for Austria. Our model projects a mean advance of blooming of –1.6 ± 0.9 days per decade, shifting the bloom onset towards early April by the end of the 21st century. Our findings indicate that overall frost risk for apple cultures will remain in a warmer climate and potentially even increase due to a stronger connection between blocking and cold spells in early spring that can be identified from observational data. To prospectively deal with frost risk, measures are needed that either stabilize crop yields or ensure farmers’ income by other means. We identify appropriate adaptation measures and relate their costs to the potential frost risk increase. Even if applied successfully, the costs of these measures in combination with future residual damages represent additional climate change related costs. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci, is a major threat to tomato Solanum lycopersicum and ranks as one of the world’s 100 most invasive pests. This is the first study of B. tabaci (Biotype B and Q) global distribution, focusing on risk levels of this invasive pest, in areas projected to be suitable for open field S. lycopersicum cultivation under climate change. This study aims to identify levels of risk of invasive B. tabaci for areas of suitability for open field S. lycopersicum cultivation for the present, 2050 and 2070 using MaxEnt and the Global Climate Model, HadGEM2_ES under RCP45. Our results show that 5% of areas optimal for open field S. lycopersicum cultivation are currently at high risk of B. tabaci. Among the optimal areas for S. lycopersicum, the projections for 2050 compared to the current time showed an extension of 180% in areas under high risk, and a shortening of 67 and 27% in areas under medium and low risk of B. tabaci, respectively, while projections for 2070 showed an extension of 164, and a shortening of 49 and 64% under high, medium and low risk, respectively. The basis of these projections is that predicted temperature increases could affect the pest, which has great adaptability to different climate conditions, but could also impose limitations on the growth of S. lycopersicum. These results may be used in designing strategies to prevent the introduction and establishment of B. tabaci for open-field tomato crops, and assist the implementation of pest management programs. [ABSTRACT FROM AUTHOR]

The pear (genus Pyrus) is one of the most ancient and widely cultivated tree fruit crops in temperate climates. The Mount Etna area claims a large number of pear varieties differentiated due to a long history of cultivation and environmental variability, making this area particularly suitable for genetic studies. Ninety-five pear individuals were genotyped using the simple sequence repeat (SSR) methodology interrogating both the nuclear (nDNA) and chloroplast DNA (cpDNA) to combine an investigation of maternal inheritance of chloroplast SSRs (cpSSRs) with the high informativity of nuclear SSRs (nSSRs). The germplasm was selected ad hoc to include wild genotypes, local varieties, and national and international cultivated varieties. The objectives of this study were as follows: (i) estimate the level of differentiation within local varieties; (ii) elucidate the phylogenetic relationships between the cultivated genotypes and wild accessions; and (iii) estimate the potential genetic flow and the relationship among the germplasms in our analysis. Eight nSSRs detected a total of 136 alleles with an average minor allelic frequency and observed heterozygosity of 0.29 and 0.65, respectively, whereas cpSSRs allowed identification of eight haplotypes (). These results shed light on the genetic relatedness between Italian varieties and wild genotypes. Among the wild species, compared with P. amygdaliformis, few P. pyraster genotypes exhibited higher genetic similarity to local pear varieties. Our analysis revealed the presence of genetic stratification with a ‘wild’ subpopulation characterizing the genetic makeup of wild species and the international cultivated varieties exhibiting the predominance of the ‘cultivated’ subpopulation. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In tomato, resistance to Tomato spotted wilt virus (TSWV) is conferred by the dominant gene, designated Sw-5. Virulent Sw-5 resistance breaking (SRB) mutants of TSWV have been reported on Sw-5 tomato cultivars. Two different PCR-based allelic discrimination techniques, namely Custom TaqMan™ SNP Genotyping and high-resolution melting (HRM) assays, were developed and compared for their ability to distinguish between avirulent (Sw-5 non-infecting, SNI) and SRB biotypes. TaqMan assays proved to be more sensitive (threshold of detection in a range of 50–70 TSWV RNA copies) and more reliable than HRM, assigning 25 TSWV isolates to their correct genotype with an accuracy of 100%. Moreover, the TaqMan SNP assays were further improved developing a rapid and simple protocol that included crude leaf extraction for RNA template preparations. On the other hand, HRM assays showed higher levels of sensitivity than TaqMan when used to co-detect both biotypes in different artificial mixtures. These diagnostic assays contributed to gain preliminary information on the epidemiology of TSWV isolates in open field conditions. In fact, the presented data suggest that SRB isolates are present as stable populations established year round, persisting on both winter (globe artichoke) and summer (tomato) crops, in the same cultivated areas of Southern Italy. [ABSTRACT FROM AUTHOR]

Tomato yellow leaf curl virus (TYLCV) causes great losses in tomato production. In addition to tomato, TYLCV infects many crops or weeds as alternative hosts. These alternative hosts may serve as reservoirs for TYLCV survival and spread. Here, we tested the capability of cultivated, flue-cured tobacco to act as a reservoir host plant for TYLCV. TYLCV DNA was detected in nine flue-cured tobacco cultivars inoculated with an infectious TYLCV clone, although no visible symptoms developed on TYLCV-infected tobacco plants. The percentage of whiteflies with viral DNA increased with an increasing acquisition access period (AAP) and reached 100% after a 12 h AAP on infected tobacco plants. Using infected tobacco plants as virus resources, TYLCV was capable of being transmitted to tobacco and tomato plants by whiteflies, and typical symptoms of TYLCV infection were observed on infected tomato plants but not on infected tobacco plants. Our results suggest that flue-cured tobacco can serve as a reservoir host plant for TYLCV and may play an important role in the spread of TYLCV epidemics in China. [ABSTRACT FROM AUTHOR]

Citrus Huanglongbing (HLB), a highly devastating citrus disease, is associated with ‘Candidatus Liberibacter asiacitus’ (CLas), a member of phloem-inhabiting α-proteobacteria. HLB can affect all cultivated citrus and no cure is currently available. Previous studies showed that Kaffir lime (Citrus hystrix), primarily grown in South Asia and Southeast Asia, was tolerant to HLB but the molecular mechanism remains unknown. In this study, gene expression profiling experiments were performed on HLB-tolerant C. hystrix and HLB-susceptible C. sinensis three months after inoculation with CLas using RNA-seq data. Differentially expressed genes (DEGs) in the two citrus cultivars were mainly involved in diverse cellular functions including carbohydrate metabolism, photosynthesis, cell wall metabolism, secondary metabolism, hormone metabolism and oxidation/reduction processes. Notably, starch synthesis and photosynthesis process were not disturbed in CLas-infected C. hystrix. Most of the DEGs involved in cell wall metabolism and secondary metabolism were up-regulated in C. hystrix. In addition, the activation of peroxidases, Cu/Zn-SOD and POD4, may also enhance the tolerance of C. hystrix to CLas. This study provides an insight into the host response of HLB-tolerant citrus cultivar to CLas. C. hystrix is potentially useful for HLB-tolerant/resistant citrus breeding in the future. [ABSTRACT FROM AUTHOR]