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During a fifteen-year period of work carried out by the Test facility for the farm acquisition to be used to conduct efficacy trials against nematodes, a survey was carried out on nematological problems occurring in the Campania Region. The investigations has shown that the genus Meloidogyne spp., in particular the species M. incognita, is the most widespread and harmful trophic group. These nematodes are found in particular on horticultural plants in the sandy soils of the coastal areas and especially under protected conditions. Infestations of the cyst nematodes Globodera rostochiensis and G. pallida on potato in the neighbouring Caserta and Neapolitan areas, H. goettingiana on leguminous plants, especially peas, and H. daverti on carnation in the Vesuvian foothills are also common. In the Nocerino-Sarnese countryside, infestations by the stem and bulb nematode, Ditylenchus dipsaci, on onions are still severe. On fruit trees are common Mesocriconema xenoplax on actinidia, Meloidogyne incognita and M. hapla on peach trees and Tylenchulus semipenetrans on citrus fruits. Among the virus transmitting nematodes, Xiphinema diversicaudatum is very harmful to peach trees in Terra di Lavoro, in the Carinola (Caserta) area, and X. index to grapevines in the Benevento and Avellino areas. [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.)

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.)

Brown rot, caused by Monilinia spp., is a major peach disease worldwide. In this study, the response of peach cultivars Royal Glory (RG) and Rich Lady (RL) to infection by Monilinia fructicola or Monilinia laxa, was characterized. Phenotypic data, after artificial inoculations, revealed that 'RL' was relatively susceptible whereas 'RG' was moderately resistant to Monilinia spp. Comparative proteomic analysis identified mesocarp proteins of the 2 cultivars whose accumulation were altered by the 2 Monilinia species. Functional analysis indicated that pathogen-affected proteins in 'RG' were mainly involved in energy and metabolism, while, differentially accumulated proteins by the pathogen presence in 'RL' were involved in disease/defense and metabolism. A higher number of proteins was differentiated in 'RG' fruit compared to 'RL'. Upon Monilinia spp. infection, various proteins were-down accumulated in 'RL' fruit. Protein identification by mass spectrometric analysis revealed that several defense-related proteins including thaumatin, formate dehydrogenase, S-formylglutathione hydrolase, CBS domain-containing protein, HSP70, and glutathione S-transferase were up-accumulated in 'RG' fruit following inoculation. The expression profile of selected defense-related genes, such as major latex allergen, 1-aminocyclopropane-1-carboxylate deaminase and UDP-glycoltransferase was assessed by RT-PCR. This is the first study deciphering differential regulations of peach fruit proteome upon Monilinia infection elucidating resistance responses. [ABSTRACT FROM AUTHOR]

Highlights • A structured illumination (SI) system was first used for detection of early decay in peaches. • The SI technique was superior to conventional uniform illumination for disease infection detection. • The pixel-based CNN method achieved excellent disease detection accuracies. Abstract Peaches are susceptible to fungal infection after harvest, and detection of the symptom at early stage is critical to reducing economic loss for the industry, but is challenging because the symptom is not visible at the surface of infected fruit. This research was therefore aimed to develop a non-destructive and accurate method, based on structured-illumination reflectance imaging (SIRI), for detection of early fungal infection in peaches. Patterned spectral images for seven wavelengths between 690 nm and 810 nm were acquired from 600 peaches of different decayed levels, using a multispectral SIRI system, under sinusoidally-modulated illumination at the spatial frequencies of 60, 100 and 150 m−1. The resultant direct component (DC) images, which are equivalent to images acquired under uniform, diffuse illumination, could not reveal the slightly diseased symptom for peaches, but the symptom was visible from the alternating component (AC) images and ratio images calculated from the AC and DC images for the three frequencies. Watershed algorithm and partial least squares discriminant analysis were used for classification of diseased peaches based on the AC and ratio images, which achieved detection rates in the range of 65%–87%. Consistently better detections of diseased peaches were achieved with the AC images at the wavelength of 730 nm and the spatial frequency of 100 m−1. The pixel-based convolutional neural network for the AC images of 730 nm and 100 m−1 frequency achieved an excellent detection rate of 98.6% for all peach samples, and it also demonstrated superior performance for detecting early decayed peaches with non-visible disease infection symptom at a detection rate of 97.6%. For comparison, detection rates of diseased peaches by the three classification methods for the DC images were consistently lower. This study has shown that SIRI, coupled with an appropriate image classification method, can be effective for early disease detection of peaches. [ABSTRACT FROM AUTHOR]

Hpidemics of phony peach disease (PPD), caused by Xylella fastidiosa, are of increasing concern to peach (Primus persica) producers in the southeastern United States. Primers suitable for both conventional PCR (cPCR) and quantitative PCR (qPCR), along with optimal tissue and sampling time, are needed for comparative and reliable detection of X. fastidiosa. In this study, we developed and assessed novel primers for X. fastidiosa and for peach and compared detection of X. fastidiosa in four peach tissue types sampled at three time points using both cPCR and qPCR. Primer C06Xf-bamA was extensively tested for reliable detection of X. fastidiosa due to the more consistent intensity of the cPCR products and the marginally lower average quantification cycle (Cq) values of the qPCR products, compared with the other primers screened. Among the four peach tissue types tested, only root samples demonstrated reliable and consistent detection of X. fastidiosa; stem, petiole, and leaf samples, regardless of source trees, primers used, sampling times, or PCR methods (cPCR or qPCR), were unreliable for detection, due to insufficient quantity of DNA of X. fastidiosa in these samples based on the relative quantification assay. The Cq means and ratios were compared and statistically analyzed, to ascertain effects of source tree, tissue type, sampling time, and primer. Differences in detection sensitivity and the Cq means among sampled dees, sampling times, tested primers, and tissues (except root) were not significant or were inconsistent precluding further exploitation. In summary, these novel primers are a useful resource for detecting X. fastidiosa, and based on our results, root is the only tissue type reliable for year-round detection of X. fastidiosa in peach. Further research on potential utilization of aboveground tissues for PCR detection of X. fastidiosa are discussed. [ABSTRACT FROM AUTHOR]

Aims: Aspergillus aculeatus, a pathogen of peaches, can cause soft rot and lead to economic losses in agricultural production. However, studies on the prevention of soft rot caused by A. aculeatus have rarely been reported. Tricyclazole (TCZ) is a fungicide that has been widely used in disease prevention of various crops but the inhibitory mechanism of TCZ on A. aculeatus is unknown. Our aim was to determine the effects of TCZ on A. aculeatus. Methods and Results: In our study, TCZ inhibited the growth of fungal colonies when applied at 0·5–6 mmol l−1 and inhibited the production of melanin at 3 mmol l−1. Conidia exposed to TCZ were less effective at causing the disease in inoculated samples, and electrical conductivity, divulgation of nucleic acids and proteins rose with increasing concentrations of TCZ. Microscopic results suggest that TCZ damages not only the cell wall but also the cell membrane. Results of qRT‐PCR showed that TCZ had no significant effect on the regulation of genes coding for laccase, apoptosis and hypothetical protein; however, it significantly down‐regulated genes coding for cellulase, chitinase and sterol. Conclusions: Tricyclazole can influence the pathogenic ability of A. aculeatus by damaging the cell structure of hyphae and conidia, reducing the melanin production, and altering the expression of pathogenic‐related gene. Significance and Impact of the Study: The results explained the potential cause and mechanism TCZ produced in A. aculeatus. Our research offers scientific insights into future research interest relative to using TCZ in the treatment of soft rot caused by A. aculeatus. [ABSTRACT FROM AUTHOR]

A non-destructive method for detection of fungal contamination in peaches using an electronic nose (E-nose) is presented. Peaches were inoculated with three common spoilage fungi, Botrytis cinerea , Monilinia fructicola and Rhizopus stolonifer and then stored for various periods. E-nose was then used to analyze volatile compounds generated in the fungi-inoculated peaches, which was then compared with the growth data (colony counts) of the fungi. The results showed that changes in volatile compounds in fungi-inoculated peaches were correlated with total amounts and species of fungi. Terpenes and aromatic compounds were the main contributors to E-nose responses. While principle component analysis (PC1) scores were highly correlated with fungal colony counts, Partial Least Squares Regression (PLSR) could effectively be used to predict fungal colony counts in peach samples. The results also showed that the E-nose had high discrimination accuracy, demonstrating the potential use of E-nose to discriminate among fungal contamination in peaches. [ABSTRACT FROM AUTHOR]

Background: The peach fruit moth, Carposina sasakii Matsumura (Lepidoptera: Carposinidae), poses a serious threat to a variety of fruits and causes significant economic loss owing to difficulties in its prevention and control. The olfactory sense is generally acknowledged to be a novel target for pest control. However, a systematic study of the olfactory genes expressed in C. sasakii has not been reported yet. Here, we reported the antennal transcriptome of C. sasakii using high-throughput sequencing and annotated the main chemosensory multi-gene families. Results: In the chemosensory gene families, 29 odorant-binding proteins, 13 chemosensory proteins, 1 sensory neuron membrane protein, 52 odorant receptors, 8 ionotropic receptors and 11 gustatory receptors were annotated in the C. sasakii antennal transcriptome. The number of olfactory genes obtained in our transcriptome was consistent with that identified in other lepidopteran insects, confirming that we basically accomplished the annotation of the chemosensory genes of C. sasakii in the adult antennal transcriptome. All sequences were annotated and analyzed by BLAST (basic local alignment search tool), and some chemosensory genes with specific functions were named according to the BLAST results and phylogenetic trees. Based on the expression profile in the transcriptome and phylogenetic analysis, differentially expressed genes (DEGs) were analyzed in both male and female adults. Finally, fluorescence quantitative real-time PCR was used to identify the male-specific or female-specific chemosensory genes that were putatively related to odor detection and recognition. Moreover, expression levels of OR33 and PBP2 were significantly higher in males than in females, indicating that these genes may interact with sex pheromones. We found some conserved antennal IRs and GRs involved in detecting sugar compounds (GR2, GR5, GR6, GR8) and carbon dioxide (GR1), which were also identified based on phylogenetic analysis. Conclusions: There are 114 putative chemosensory proteins expressed in C. sasakii identified in this study. The identification of these proteins will make the molecular mechanism of odor recognition accessible. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to analyze the infection ability of Rhizobium radiobacter from Rosa chinensis to peach tree, so as to provide a theoretical basis for the identification and control of crown gall of peach. [Methods] With peach variety "Chiyohime" as an experimental material, R. radiobacter GOU1 was extracted from crown gall tissue of R chinensis susceptible to crown gall, and its infection ability to peach tree was studied by in-vitro dip method. [ Results] Stem segments of peach tree were inoculated with R. radiobacter GOU1 by in-vitro dip method. Calli grew rapidly after inoculation, and 28 d later, the infection rate of R. radiobacter GOU1 was 50%, indicating that R. radiobacter GOU1 could infect peach tree easier. The infection on stem segments of peach tree could be detected in the fourth week by in-vitro dip method. Culturing peach stem segments in MS medium containing 10 (JLM/L NAA and 10 (JLM/L BAP in vitro is beneficial to survival and could promote growth of callus. [ Conclusions ] The detection rate of R. radiobacter GOU1 infection on stem segments of peach tree did not change from the fourth week to the sixth week. Therefore, in future studies, the detection of R. radiobacter infection on inoculated stem segments of peach tree could be performed after 4 weeks of culture rather than 6 weeks of culture. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Taiwan Agricultural Research is the property of Taiwan Agricultural Research Institute, Council of Agriculture, Executive Yuan 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.)

Peach orchards in the northeast of Spain were severely affected in 2012 by a previously unreported disease in this area. The symptoms included early reddening, leaf curling, decline, abnormal fruits, and in some cases death of the peach trees. All the infected peach samples were positive for ‘Candidatus Phytoplasma pyri’, but none were infected by the ‘Ca. Phytoplasma prunorum’. In this work, potential vectors able to transmit ‘Ca. Phytoplasma pyri’ from pear to peach and between peach trees were studied and their infective potential was analysed at different times of the year. Transmission trials of the phytoplasma with potential vectors to an artificial feeding medium for insects and to healthy peach trees were conducted. Additionally, isolated phytoplasmas were genetically characterized to determine which isolates were able to infect peach trees. Results showed that the only insect species captured inside peach plots that was a carrier of the ‘Ca. Phytoplasma pyri’ phytoplasma was Cacopsylla pyri. Other insect species captured and known to be phytoplasma transmitters were present in very low numbers, and were not infected with ‘Ca. Phytoplasma pyri’ phytoplasma. A total of 1928 individuals of C. pyri were captured in the peach orchards, of which around 49% were phytoplasma carriers. All the peach trees exposed to C. pyri in 2014, and 65% in 2015, were infected by ‘Ca. Phytoplasma pyri’ 1 year after exposure, showing that this species is able to transmit the phytoplasma to peach. Molecular characterization showed that some genotypes are preferentially determined in peach. [ABSTRACT FROM AUTHOR]

Effects of 0.1 mM melatonin (MT) on chilling injury (CI), membrane fatty acid content and phenolic metabolism in peach fruit were studied during storage at 1°C for 28 days. MT treatment delayed the development of CI in peach fruit, as was illustrated by MT-treated fruit showing lower CI incidence, CI index and firmness loss than the control. MT treatment prevented membrane lipid peroxidation and contributed to maintaining a higher ratio of unsaturated to saturated fatty acids in peach fruit. MT treatment also stimulated the activities of glucose-6-phosphate dehydrogenase, shikimate dehydrogenase and phenylalanine ammonia lyase, but inhibited the activities of polyphenol oxidase and peroxidase. This would help in activating the accumulation of total phenolic and endogenous salicylic acid that might have a direct function in alleviation of CI. These results indicate that MT treatment can be an effective technique to reduce postharvest CI during low temperature storage of peach fruit. [ABSTRACT FROM AUTHOR]

Argyrotaenia tucumana Trematerra & Brown, 2004 (Lepidoptera: Tortricidae) was detected feeding on peach fruit crops in the south of Santa Fe province. The damages observed in January 2017 were superficial and close to the peduncle of the fruit. This is the first record of this pest on this crop in Argentina. [ABSTRACT FROM AUTHOR]

In this study, the effects of oligochitosan treatment on controlling postharvest diseases in Dongxue peach (Prunus Persica L. Batsch, cv Dongxuemi) were examined and the possible underlying mechanisms were discussed. Results showed that the disease incidence and lesion area in peach fruit inoculated with Monilinia fructicola and Penicillium expansum were all remarkably reduced by oligochitosan treatment. Oligochitosan treatment inhibited spore germination and mycelial growth of the two fungi in vitro. Oligochitosan treatment also induced upregulation of the salicylic acid signalling pathway-related genes (NPR1, PR1 and phenylalanine ammonia lyase) and enhanced the levels of total phenolics, flavonoids and lignin in peach. Meanwhile, enzymatic activities of superoxide dismutase, catalase, polyphenoloxidase, ascorbate peroxidase and phenylalanine ammonia lyase also increased. These findings suggest that the effects of oligochitosan on the disease control of peach fruit may be associated with its direct antimicrobial effects as well as increasing antioxidant, phenylpropanoid metabolism and accumulating antifungal compounds by activating the salicylic acid-dependent pathway. [ABSTRACT FROM AUTHOR]

The maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is a worldwide pest on stored products, as maize, wheat and rice grains. However, in South Brazil, these weevils have been found attacking fruits in field conditions. It was reported that adults attack fruits to feeding, but there was no information of oviposition and larval development on these hosts. Furthermore, due to monitoring apple orchards, was observed that some fruits showed distinct kind of punctures, suggesting a oviposition by these weevils. The present study reports first record an unusual behavior of S. zeamais by oviposition and larval development in peach and apple fruits. The study was conducted in laboratory conditions (temperature: 25 ± 1 °C, RH: 70 ± 10% and photophase of 14 h). Peach and apple fruits were offered to S. zeamais females. The oviposition and duration of immature stages in peach were measured in fruits and in corn grains, used as control observation. The oviposition and larval development occurred in peach and apple fruits, with a development until to adult. The average of egg-to-adult was 47.4 d in peach and and 45.1 d apple fruits, respectively, while in corn grains, its natural host, the duration was 38.2 d. These results show that the damage caused by S. zeamais in peach and apple fruits may be due to oviposition and the development of immature stages. So, the novelty is in demonstrating that the maize weevil does not just feed as an adult opportunistically on the fruits, but can complete a full life cycle using fresh fruits. [ABSTRACT FROM AUTHOR]

Carposina sasakii Matsumura is one of the most serious fruit-damaging pests in Southern East Asia. The management of C. sasakii using sex pheromones has proven to be simple, effective and environmentally friendly with respect to monitoring and controlling this pest., To apply sex pheromone-based pest control techniques effectively, we characterized a range of application parameters, as well as the effects of synthetic sex pheromones, in jujube orchards. Trapping radius was determined by comparing the mean number of trapped individuals at different inter-trap distances, and mating disruption parameters were inferred by comparing the rate of trapping efficiency reduction and the infestation ratio of fruits in the experimental fields by uniformly placing different number/types of lures/100 m2., These studies revealed capture rates with significant differences across 10-50-m inter-trap distances: for example, a 30-m or greater inter-trap distance was suitable for monitoring and mass trapping, whereas distances <20 m significantly decreased the trapping efficiency in the testing area., The studies lay the foundation for the implementation of these technologies within the context of a well-conceived control strategy against this significant agricultural pest. [ABSTRACT FROM AUTHOR]

The brown rot caused by the fungus Monilinia spp. is the main disease of peach (Prunus persica) that occurs from flowering to post-harvest fruit. The objective of this study was to identify the species that causes brown rot in Rio Grande do Sul state using molecular method based on specific primers and study the morphological variability of Monilinia isolates using classic characterization methods. The isolates were collected in the main producing regions of peaches and determination of species was performed by using specific primers to the genus Monilinia. The culture media BDA®, peach juice and Pagnocca were used for the morphological characterization of isolates. Molecular study showed that all isolates from Rio Grande do Sul are the species M. fructicola. In the morphological characterization, such as mycelial diameter, color, margin, shape and elevation of the colonies and dry mass of mycelium, there are variability in the analyzed characteristics of the isolates in the three-culture media used. In the comparing the culture media, the higher dry matter values and diameter of colony isolates were obtained in Pagnocca and peach juice means. [ABSTRACT FROM AUTHOR]

We determined the complete genome sequence of a highly divergent South Korean (SK) isolate of a cherry-associated luteovirus (ChALV) from peach. The ChALV-SK genome consists of 5,815 nucleotides, and contains five open reading frames (ORFs). A comparative analysis of the full genome showed only 73.1% nucleotide sequence identity with a recently described ChALV from the Czech Republic (CZ). Amino acid similarities of the individual ORFs between ChALV-SK and other luteoviruses range from 17.3 to 92%, which places the new isolate close to the species demarcation value for luteoviruses. Results show our ChALV-SK isolate to be highly diverged from the ChALV-CZ isolate. [ABSTRACT FROM AUTHOR]

Peaches are popular, nutritious and widely consumed. Being a tree crop, it is considered a low risk fruit, with no direct water contact, and no previous foodborne disease outbreaks associated with its consumption. However, in 2014 the pioneer association between stone fruit and a foodborne illness was reported, linking Listeria monocytogenes to stone fruit. This highlights the need for better understanding of risk associated with contaminated fresh stone fruit, in order to implement adequate preventative measures. No information is available on the presence of foodborne pathogens on peaches in the supply chain. A case study approach was therefore followed to assess foodborne pathogen presence on the farm, focusing on the impact of irrigation water, facility sanitation and hygiene by collecting various fruit and environmental samples (n = 428). This study demonstrates the effectiveness of integrating basic microbial testing with safety management and risk assessment tools that can be collectively used to improve the food safety management system. No Salmonella Typhimurium was detected from samples, however, Escherichia coli O157:H7, Listeria spp. and Staphylococcus aureus were detected on fruit and environmental samples. Despite the GlobalG.A.P. certification status of the farm, livestock frequented water sources which lead to E. coli O157:H7 contamination. This conclusion was based on positive detection of foodborne pathogens from the water sources and subsequent removal of livestock which resulted in a definite decrease in pathogen detection. A number of E. coli O157:H7 and S. aureus were detected during the second year of monitoring from environmental samples and it was observed that the personal hygiene and facility sanitation was not adequately enforced. Based on feedback given to the farmer, enforcement was improved and a definite decrease in foodborne pathogens was observed in the following sampling cycle. Areas of risk that were still identified following the fourth year of monitoring included the water source used for irrigation and poor sanitation in the production and processing facilities. Limited foodborne pathogen prevalence on peaches over the full study period as well as the extended export supply chain at controlled temperatures resulted in low-to-medium calculated consumer risk. The correct and meticulous implementation of integrated and holistic pre- and post-harvest food safety management systems is therefore essential to prevent produce contamination, reduce the consumer risk and therefore ensure overall product safety. [ABSTRACT FROM AUTHOR]

Studying the susceptibility of peach trees to Grapholita molesta (Busck) is one of the major steps in the development of pest-resistant peach varieties. This work evaluated the susceptibility of 55 genotypes of the "Prunus Rootstock Collection" ("Coleção Porta-enxerto de Prunus") of Embrapa Temperate Climate (Pelotas, Rio Grande do Sul, Brazil) to the natural infestation of G. molesta, assessed the oviposition preference of G. molesta in choice and no-choice bioassays, and estimated the biological parameters and the fertility life table on different Prunus spp. genotypes in the laboratory. Genotypes Prunus kansuensis (Rehder), I-67-52-9, and I-67-52-4 were the most susceptible to G. molesta infestation in the field (>60% of branches infested), while 'Sharpe' (Prunus angustifolia x Prunus spp.) and Prunus sellowii (Koehne) were the least infested (0% of branches infested). In choice and no-choice bioassays, G. molesta preferred to oviposit on P. kansuensis when compared with Sharpe. The Sharpe genotype also showed an antibiosis effect, resulting in negative effects on the fertility life table parameters when compared with the genotypes P. kansuensis and 'Capdeboscq.' The results found in the present study can provide information to initiate a long-term breeding program moving desired G. molesta resistance traits from the rootstock into the Prunus spp. cultivars. [ABSTRACT FROM AUTHOR]

The role of different shapes of methyl eugenol based traps in peach and pear were studied at PunjabAgricultural University, Ludhiana, India against major fruit fly species i.e. Bactrocera zonata (Saunders) and Bactrocera dorsalis (Hendel). In this experiment, cylindrical traps, spherical traps, triangular traps and PAU fruit fly traps were used. The results revealed that triangular traps (71.58 males) had captured significantly more population followed by cylindrical traps (38.86 males), PAU fruit fly traps (29.61 males) and spherical traps (21.30 males) in peach; whereas in pear, the number of fruit fly males captured/trap/week were significantly high in triangular traps (127.92 males) as compared to PAU fruit fly traps (55.30 males), cylindrical traps (51.08 males) and spherical traps (42.44 males). The mean percentage of fruit fly damage was also lowest in triangular traps in peach (4.33%) and in pear (6.72%) respectively. However, cost: benefit ratio was quite low in triangular traps in both peach (1:30.86) and pear (1:20.93). [ABSTRACT FROM AUTHOR]

Brown rot caused by the fungi Monilinia laxa (Aderhold and Ruhland) Honey, M. fructicola (Winter) Honey, or M. fructigena (Aderhold and Ruhland) is a serious fungal disease of peaches. The fungal infection process begins when fungal conidia germinate on the fruit surface to produce germ tubes and/or appressoria, and the incidence of brown rot increases as fruit approaches maturity. The interaction between the fungal infection process, peach maturity, and the environmental conditions is not well understood. Accordingly, the objectives of this investigation were to investigate germ tube and appressorial formation by M. laxa and M. fructicola when they were exposed to peach skin from mature and immature fruit at various temperatures and relative humidities (RHs). The greatest number of germ tubes was found when M. laxa or M. fructicola was incubated in culture medium which contained a skin extract of mature peaches. In contrast, the greatest number of appressoria was found when M. laxa or M. fructicola was incubated in culture medium which contained a skin extract of immature peaches. Although M. fructicola produced the same number of germ tubes and appressoria at 4 °C, M. fructicola produced more germ tubes than appressoria at temperatures higher than 10 °C. M. laxa produced more germ tubes than appressoria at any temperature, except when it was incubated for 48 h on culture medium which contained a skin extract of immature peaches at 10 °C at 80% or 100% RH, or at 25 °C at 60% RH. M. laxa conidia germinated better than M. fructicola conidia at low temperatures. Germ tube and appressorial formation by Monilinia spp. were influenced by fruit postharvest handling. The number of germ tubes that were formed by M. laxa conidia was significantly greater than that for M. fructicola when the conidia were incubated at 100% RH, and this number increased after 3 days of refrigeration. The number of appressoria that were formed by both Monilinia spp. also increased after 3 consecutive days of refrigeration. Negligible or no germination of M. fructicola and M. laxa conidia occurred when the RH was 60%. We concluded that the dissimilar abilities of M. laxa and M. fructicola to germinate and form appressoria at low temperatures conferred a competitive advantage to M. laxa to survive during fruit postharvest refrigeration and cold storage at 4 °C. [ABSTRACT FROM AUTHOR]

Since 2005, foliar symptoms of a presumptive virus disease, including chlorotic and necrotic ring patterns or blotches, have been observed in peach (Prunus persicaL.) trees in Aguascalientes, Mexico. Infected leaf samples were analysed based on general scanning forPotyvirusby dot blot and by RT-PCR for specific detection. The present study describes the identification ofPlum pox virus(PPV) as the causal agent of the virus disease on peach orchards in Aguascalientes, Mexico. RFLP analyses showed that PPV Mexican strain belongs to genotype D, previously detected in North America (USA and Canada). To our knowledge, this is the first report of the presence of PPV in Mexico and this data can positively contribute to establish appropriate phytosanitary control measures, in Mexico as well worldwide. [ABSTRACT FROM AUTHOR]

Phytophagous stink bugs (Hemiptera: Pentatomidae) are primary pests in most fruit, vegetable, grain, and row crops worldwide. Pheromones have been identified and synthesized for several species of economically important stink bug pests. When yellow pyramid traps are baited with lures containing these pheromones, significantly more stink bug adults are captured in the field than without lures. Our specific objective for this study was to examine the attractiveness of the Euschistus aggregation pheromone, methyl ( E, Z)-2,4-decadienoate (MDD), to stink bug nymphs by using yellow pyramid traps baited and not baited with MDD lures in peanut fields and alongside pecan and peach orchards. At orchard locations, captured nymphs were predominantly Euschistus servus (Say) followed by E. tristigmus (Say), E. ictericus (L.), and Thyanta custator custator (F.). In peanut, E. servus, E. tristigmus, and Chinavia hilaris (Say) nymphs were caught in traps. Nymphal capture of E. servus, E. tristigmus, and C. hilaris was significantly higher in traps with MDD lures than in non-baited traps demonstrating that these nymphs were attracted to the synthetic aggregation pheromone. Pyramid traps baited with aggregation pheromone can be used as monitoring tools to assess the presence and seasonal development of certain stink bug pest species on crop and non-crop host plants and perhaps to predict timing of dispersal into and/or out of a crop. [ABSTRACT FROM AUTHOR]

The residual activity of horticultural mineral oil ( HMO) on the ability of green peach aphids, Myzus persicae (Sulzer), ( GPA) to transmit Plum pox virus ( PPV) to peach was measured by infection rates of detached leaves from plants sprayed with either HMO or water as a control that were inoculated using transfer of 25 viruliferous aphids per leaf at 0, 2, 4, 7, 9, 11 and 14 days after treatment ( DAT). Persistent effects of HMO residue on the probing and feeding behaviours of GPA were also monitored with the electrical penetration graph ( EPG) system. For glasshouse-grown peach seedlings, the residual activity of HMO reduced PPV infection rates by more than 58% for up to 4 DAT following an initial reduction of approximately 81%. EPG recordings of GPA feeding behaviour showed that HMO significantly delayed first feeding probes and first intracellular punctures by more than 50 min without changing the ensuing stylet penetration behaviour. Applying HMO reduced virus infection rates for up to a week depending on the environmental conditions. EPG monitoring of aphid probing showed that HMO reduced the mean duration and mean number of potential drop ( PD) phase feeding occurrences, compared with the water control. A reduction in the PD that has been shown to be related to the transmission of non-persistently transmitted viruses may partly explain the reduction in PPV infection rates. [ABSTRACT FROM AUTHOR]

The efficacy of pheromone-based mating disruption for control of the peachtree borer Synanthedon exitiosa (Say) in small-scale peach orchards (<0.1 ha) was evaluated in a total of six blocks at two locations in New Mexico, USA, from 2010 to 2015. In treated orchards, commercial pheromone dispensers were deployed at rates of approximately 500 or 600 per ha. Pheromone-based monitoring traps were installed in each block (treated and untreated), and catches of male moths were recorded throughout each growing season to assess the effectiveness of pheromone treatments and to determine the pest's seasonal flight activity. Levels of larval trunk infestation were assessed twice yearly by inspecting all trees at and below soil level. Infestation levels in an unreplicated block of mature peaches at one site (Los Lunas) declined from 57.5% to 8.4% while under pheromone treatment (2010-2011). Pheromone treatments in this block were discontinued in 2012, and infestation levels subsequently increased to 16.9% by spring 2015. In a replicated study in four other peach blocks at the same site, annual application of pheromones from 2012 to 2014 resulted in a significant difference in larval infestations in treated blocks compared to untreated blocks. In addition, when a single block of infested peaches at a second site (Alcalde) was treated with pheromone dispensers for three consecutive years, trunk infestation levels declined significantly, but were not completely eliminated. These results indicate that mating disruption can help protect even very small orchards from damage by S. exitiosa. However, the technique is likely to be more effective where such orchards are relatively isolated and/or where the surrounding pest pressure is moderate or low. [ABSTRACT FROM AUTHOR]

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an invasive species that has become an important orchard pest in the Mid-Atlantic region of the US. Adults and nymphs feed on tree fruit. Feeding injury from adults has been characterized but the injury from nymphs has not been examined systematically. Since the four plant-feeding instars of H. halys (second through fifth) differ substantially in size, it is plausible that the effects of their feeding on fruit injury and injury expression may differ among them. We compared feeding injury at harvest from young nymphs (second plus third instars), older nymphs (fourth plus fifth instars), and adults that were caged on ‘Smoothee Golden’ apples and ‘Redhaven’ peaches in early June (peach and apple), late July (peach), and late August (apple). Individual apples and peaches were caged at fruit set and assigned to the following treatments (n = 28/treatment): 1) control (no H. halys ), 2) young nymphs or 3) adults early in the season, and 4) young nymphs, 5) older nymphs or 6) adults later in the season. Fruit in each treatment were exposed to 3–4 young nymphs, two older nymphs or 1–2 adults placed in the cages for 96 h and evaluated for external and internal feeding injury within 36 h after harvest. No injury was recorded from unexposed peaches or apples. The percentage of injured fruit and number of injuries per fruit varied significantly among the exposed treatments. Early season feeding by young nymphs yielded the least injury to peaches and apples. In apples, the highest percentage of injured fruit and number of injuries per fruit were caused by late season feeding by adults. In peaches, early season adult feeding produced the highest percentage of injured fruit and injuries per fruit. More internal than external injury was recorded on peach and no such difference was observed on apple. The implications of these findings on H. halys management in fruit orchards are discussed. [ABSTRACT FROM AUTHOR]

Peach, Prunus persica (L.) Batsch (Rosaceae), has been reported to be a host of the apple maggot fly, Rhagoletis pomonella (Walsh, 1867) (Diptera: Tephritidae), an important quarantine pest of apple (Malus domestica Borkhausen) (Rosaceae) in the western U.S.A. However, all reports of peach as a host appear unreliable. Here, we tested the hypothesis that apple maggot does not utilize peaches in western Washington state. In 2013, unbaited sticky yellow rectangle traps were hung in a peach orchard ~50 m from neglected apple trees in Vancouver, Washington. During 2013-2015, peaches in the orchard were collected, peaches were hung in infested apple trees, and peaches were exposed to flies in the laboratory. In 2013, 24 flies were caught on 200 traps in the peach orchard, but no larvae emerged from 4,243 'Alberta' or 'Redhaven' peaches collected under ~200 trees in 2013 and 2014 or from peaches hung in apple trees in 2013. In 2015, however, 24 apple maggot larvae emerged from 804 'Starfire' or 'PF 23' peaches, specifically from collections under two of 13 trees. In addition, in one of four laboratory tests, 11 larvae emerged from 'Redhaven' peaches exposed to apple maggot flies. Contrary to our prediction, results definitively show that peach can be an occasional developmental host for apple maggot larvae in the field and that apple maggot flies can be successfully reared using peach as a host in the laboratory. [ABSTRACT FROM AUTHOR]

Brown rot can lead to considerable fruit losses in peach orchards and cultural practices likely to contend this major disease have to be promoted. In order to limit peach brown rot incidence in a three-year-old mid-season maturing peach orchard of the cultivar ’Ruby Bright’, four combinations of irrigation and soil management treatments were assessed: conventional (Conv) irrigation (I) and soil management (S) (ConvI+ConvS); modified (Mod) irrigation and soil management (ModI+ConvS); conventional irrigation and modified soil management (ConvI+ModS); and modified irrigation and soil management (ModI+ModS). Conventional irrigation and soil management in the tree row consisted of irrigation scheduling using tensiometer readings and herbicide use, respectively. Modified irrigation and soil management in the tree row consisted of water deprivation during stage III of fruit development and ground cover with white clover, respectively. For four consecutive years (2010–2013), in the conditions of the Middle Rhone Valley in France, the lowest and highest brown rot incidence were detected under (ModI+ModS) and (ConvI+ConvS), respectively, whereas brown rot incidence under (ModI+ConvS) and (ConvI+ModS) was intermediate. This lower brown rot incidence under the modified treatments occurred from one to two weeks before fruit maturity and was still observed for several days in post-harvest storage. Ground cover with white clover was shown to limit water availability in the soil after heavy rainfall compared to bare soil, probably limiting peach growth variations, well-known as a possible source of detrimental microcracks at the fruit surface. This suggests that under our conditions appropriate cultural practices, water deprivation and a clover crop cover in the tree row possibly decrease peach disease sensitivity, which might lead to the reduced use of pesticide sprays to control brown rot in the orchard. [ABSTRACT FROM AUTHOR]

Brown rot ( Monilinia fructicola ), one of the most important diseases of stone fruits, can lead to significant fruit losses in the field and postharvest. Canola and Indian mustard extracts acquired through different extraction methods, alone and in combination with thermotherapy, were tested against postharvest brown rot in peaches. Initially, canola and Indian mustard extracts collected through the methods of simple extraction (Sp), infusion (In) and maceration (Mc) were assessed for their capacity to control M. fructicola in vitro and in vivo. The Sp extracts of each species were selected to be tested under different treatment sequences, alone and in combination with thermotherapy (50 °C for 30 s) on peaches inoculated with M. fructicola . The most effective canola and Indian mustard treatment sequences were selected and compared with the chemical treatment (azoxystrobin ® , 2 g L −1 ) and a control (sterile distilled water). The Sp extractions of canola and Indian mustard were effective at postharvest control of brown rot in peaches. When these extracts were combined with thermotherapy in the sequence Sp extract + thermotherapy + Sp extract, the efficacy of postharvest brown rot control in peaches was improved. The canola Sp extract was more effective than the Sp of Indian mustard when combined with thermotherapy and it achieved a M. fructicola sporulation reduction level equal to that given by the fungicide solution when applied to “Eldorado” peaches. [ABSTRACT FROM AUTHOR]

The peach fruit moth, Carposina sasakii Matsumura (Lepidoptera: Carposinidae), is a serious pest of many pome and stone fruits and presents a quarantine problem in some export markets. To investigate the effects of irradiation on larval weight, developmental time, and mortality, 3-, 6-, 9-, 12-, and 15 d-old larvae—which were 1st, 2nd, 3rd, 4th and 5th instars, respectively—were reared within ‘Red Fuji’ apple (Malus domestica Borkh.; Rosales: Rosaceae) fruits, and gamma-irradiated at doses from 20 to 140 Gy in increments of 20 Gy. Irradiation had significant effects on larval weight, cumulative larval developmental time, and mortality. More specific findings were as follows. Body Weight. The mean body weight of late 5th instars that developed from the 4 preceding instars decreased significantly in a dose-dependent manner when larvae in any one of these preceding instars had been irradiated with gamma rays. Mean body weight reduction of late fifth instars was greatest when 3rd instars were irradiated. In contrast, when 5th instars were irradiated their mean body weight increased significantly. Cumulative Larval Development Time. The mean cumulative larval developmental times increased significantly in a dose-dependent manner in comparison to the controls when any one of the 5 instars was irradiated. Larval Mortality. Significant larval mortality occurred in the first 4 instars when any one of them had been irradiated, but none of the irradiated 5th instars died in the apple fruits, indicating that the 5th instar is the most radiotolerant larval stage. Additional Research. Further research is suggested to elucidate the mechanisms whereby the weights of 5th instars that developed from irradiated 3rd instars are substantially diminished. Also research is suggested to elucidate the mechanisms whereby the weights of irradiated 5th instars increase substantially after they have been irradiated. [ABSTRACT FROM AUTHOR]

Sharka, caused by Plum Pox Virus (PPV), is by far the most important infectious disease of peach [P. persica (L.) Batsch] and other Prunus species. The progressive spread of the virus in many important growing areas throughout Europe poses serious issues to the economic sustainability of stone fruit crops, peach in particular. The adoption of internationally agreed-upon rules for diagnostic tests, strain-specific monitoring schemes and spatial-temporal modeling of virus spread, are all essential for a more effective sharka containment. The EU regulations on nursery activity should be modified based on the zone delimitation of PPV presence, limiting open-field production of propagation materials only to virus-free areas. Increasing the efficiency of preventive measures should be augmented by the short-term development of resistant cultivars. Putative sources of resistance/tolerance have been recently identified in peach germplasm, although the majority of novel resistant sources to PPV-M have been found in almond. However, the complexity of introgression from related-species imposes the search for alternative strategies. The use of genetic engineering, particularly RNA interference (RNAi)-based approaches, appears as one of the most promising perspectives to introduce a durable resistance to PPV in peach germplasm, notwithstanding the well-known difficulties of in vitro plant regeneration in this species. In this regard, rootstock transformation to induce RNAi-mediated systemic resistance would avoid the transformation of numerous commercial cultivars, and may alleviate consumer resistance to the use of GM plants. [ABSTRACT FROM AUTHOR]

Background: Ornamental peaches cv. 'Yaguchi' (Prunus persica (L.) Batsch) can be propagated via seeds. The establishment of efficient seed treatments for early germination and seedling growth is required to shorten nursery and breeding periods. It is important, therefore, to identify potential candidate genes responsible for the effects of rinsing and chilling on seed germination. We hypothesized that longer rinsing combined with chilling of seeds can alter the genes expression in related to dormancy and then raise the germination rate in the peach. To date, most molecular studies in peaches have involved structural genomics, and few transcriptome studies of seed germination have been conducted. In this study, we investigated the function of key seed dormancy-related genes using next-generation sequencing to profile the transcriptomes involved in seed dormancy in peaches. De novo assembly and analysis of the transcriptome identified differentially expressed and unique genes present in this fruit. Results: De novo RNA-sequencing of peach was performed using the Illumina Miseq 2000 system. Paired-end sequence from mRNAs generated high quality sequence reads (9,049,964, 10,026,362 and 10,101,918 reads) from 'Yaguchi' peach seeds before rinsed (BR) and after rinsed for 2 or 7 days with a chilling period of 4 weeks (termed 2D4W and 7D4W), respectively. The germination rate of 7D4W was significantly higher than that of 2D4W. In total, we obtained 51,366 unique sequences. Differential expression analysis identified 7752, 8469 and 506 differentially expressed genes from BR vs 2D4W, BR vs 7D4W and 2D4W vs 7D4W libraries respectively, filtered based on p-value and an adjusted false discovery rate of less than 0.05. This study identified genes associated with the rinsing and chilling process that included those associated with phytohormones, the stress response and transcription factors. 7D4W treatment downregulated genes involved in ABA synthesis, catabolism and signaling pathways, which eventually suppressed abscisic acid activity and consequently promoted germination and seedling growth. Stress response genes were also downregulated by the 7D4W treatment, suggesting that this treatment released seeds from endodormancy. Transcription factors were upregulated by the BR and 2D4W treatment, suggesting that they play important roles in maintaining seed dormancy. Conclusions: This work indicated that longer rinsing combined with chilling affects gene expression and germination rate, and identified potential candidate genes responsible for dormancy progression in seeds of 'Yaguchi' peach. The results could be used to develop breeding programs and will aid future functional genomic research in peaches and other fruit trees. [ABSTRACT FROM AUTHOR]

Quality traits and nutraceutical potential of new de-pigmented peaches (“ Ghiaccio”) were investigated and compared with those of four white flesh peaches. Total soluble solids (TSS) were measured by digital refractometer, and titratable acidity (TA) by volumetric titration. Total phenolic (TPC) and anthocyanin content (TAC) were analysed spectrophotometrically and the antioxidant capacity (AC) evaluated by DPPH assay. A strong influence of genotype on quality traits and phytochemical profile of “ Ghiaccio” peaches was observed. “ Ghiaccio” series showed, on average, a higher TPC content than that of white flesh peaches, both in flesh and peels (+129% and +14%, respectively). The peels of all peaches analysed were significantly richer in TPC than the flesh. TAC was not detectable in de-pigmented genotypes; on the contrary, in the white flesh peaches, it was higher in the peels than in the flesh. AC correlated well with TPC. Data confirm, for all peaches analysed, the influence of genotype and fruit tissue on the nutraceutical properties. Among genotypes, the best candidates for “ Ghiaccio” peaches with enriched nutraceutical properties are the advanced selections GØ and GX. Observed differences in the nutraceutical potential among “ Ghiaccio” series may open new opportunities for breeding de-pigmented peach varieties with a higher nutritional value. [ABSTRACT FROM AUTHOR]

Biological control using microbial antagonists is a promising alternative approach to synthetic fungicides. However, effective biological control requires enhancing the consistency and efficacy of the antagonists used to control postharvest diseases. This study investigated the effect of chitin on the biocontrol efficacy of Rhodotorula mucilaginosa against blue mold and Rhizopus decay of peaches and on the protein expression profiles of R. mucilaginosa. The antagonistic activity of R. mucilaginosa harvested from the nutrient yeast dextrose broth (NYDB) with 0.5% chitin added was significantly improved compared with culture in NYDB without chitin. The R. mucilaginosa population cultured in chitin-supplement NYDB and nutrient yeast chitin borth (NYCB) harvested from peach wounds was more than that of R. mucilaginosa cultured in NYDB without chitin throughout the storage period except at 1 d. The protein expression profiles findings revealed that there were several differentially expressed proteins of R. mucilaginosa in the 0.5% chitin-supplemented NYDB and NYCB compared with that of R. mucilaginosa in NYDB. Most of these were cellular proteomes relating to the primary metabolic reactions such as glycoside hydrolases, phosphoribosyl pyrophosphate, and NADH dehydrogenases. Some proteins were also related to signal transmission and stress response. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga 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.)

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical 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.)

Brown rot of stone fruit is caused by three species of Monilinia , Monilinia laxa , M. fructigena , and M. fructicola . Eleven components of 20 different isolates of each of the three Monilinia species were analyzed to determine distinct aggressiveness and growth characteristics among the three fungi. M. fructicola showed the greatest lesion diameter, and the lowest incubation and latency period on fruit postharvest, however isolates of M. fructigena exhibited less aggressiveness components. Five growth characteristics of M. fructicola could be used to distinguish M. fructicola from the other two species. The dendrogram generated from only the presence of sclerotia and lesion length on infected fruit separated the 60 isolates into two clusters ( r = 0.93). One cluster was composed of the M. laxa and M. fructigena isolates and the other cluster comprised the M. fructicola isolates. However, the dendrogram generated based on the presence of stromata and sclerotia in the same colony of the three species when they were grown on potato dextrose agar, and the lesion diameter on fruit infected with each species separated the 60 isolates into three clusters ( r = 0.81). Each cluster comprised the isolates of each of three Monilinia spp. We discussed the effect of M. fructicola growth and aggressiveness differences on the displacement of M. laxa and M. fructigena by M. fructicola recorded in Spanish peach orchards and their effect on brown rot at postharvest. [ABSTRACT FROM AUTHOR]

Lasiodiplodia theobromae is a causal agent of peach (Prunus persica L.) tree gummosis, a serious disease affecting peach cultivation and production. However, the molecular mechanism underlying the pathogenesis remains unclear. RNA-Seq was performed to investigate gene expression in peach shoots inoculated or mock-inoculated with L. theobromae. A total of 20772 genes were detected in eight samples; 4231, 3750, 3453, and 3612 differentially expressed genes were identified at 12, 24, 48, and 60 h after inoculation, respectively. Furthermore, 920 differentially co-expressed genes (515 upregulated and 405 downregulated) were found, respectively. Gene ontology annotation revealed that phenylpropanoid biosynthesis and metabolism, uridine diphosphate-glucosyltransferase activity, and photosynthesis were the most differentially regulated processes during gummosis development. Significant differences were also found in the expression of genes involved in glycometabolism and in ethylene and jasmonic acid biosynthesis and signaling. These data illustrate the dynamic changes in gene expression in the inoculated peach shoots at the transcriptome level. Overall, gene expression in defense response and glycometabolism might result in the gummosis of peach trees induced by L. theobromae. [ABSTRACT FROM AUTHOR]

The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State Austria for the pesticide active substance cyclaniliprole and the assessment of applications for maximum residue levels (MRLs) are reported. The context of the peer review was that required by Regulation (EC) No 1107/2009 of the European Parliament and of the Council. The conclusions were reached on the basis of the evaluation of the representative uses of cyclaniliprole as an insecticide on apples, pears, peaches, apricots, nectarines, plums, grapes (table and wine) and potatoes and on glasshouse tomatoes, peppers and aubergines. MRLs were assessed in addition to the uses above in field Brassica vegetables, tomatoes, peppers, and aubergines. The reliable endpoints, appropriate for use in regulatory risk assessment and the proposed MRLs, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified. [ABSTRACT FROM AUTHOR]

The aim of the present study was to identify the cultivable gut bacteria associated with peach fruit fly, Bactrocera zonata, and evaluate their potential to attract adults of B. zonata. Based on culture-dependent characterization methods and 16S rRNA gene sequence analysis, bacteria were identified as members of family Enterobacteriaceae (BZM1, Klebsiella oxytoca), Microbacteriacea (BZM2, Microbacterium spp.) and Nocardiaceae (BZM4, Rhodococcus spp.). Molecular phylogeny placed Klebsiella oxytoca within gram negative γ-proteobacteria whereas, Microbacterium spp. and Rhodococcus spp. were clustered under gram positive Actinobacteria group in family Microbacteriacea and Nocardiaceae, respectively. 16S rRNA gene sequence comparison with the available NCBI database sequences further confirmed the characterizations of bacterial symbionts. Population of these bacterial species increased significantly up to the 11 day after emergence of adults and thereafter it remains constant. Among 3 bacterial symbionts, metabolites produced from K. oxytoca had the highest attraction to the B. zonata adult females over metabolites produced from other bacteria and their combinations in field bioassay. The B. zonata adult male flies attracted to metabolites produced from each bacterial symbionts alone and their combinations were less in number with comparison to the B. zonata adult females. The present study provides the first description of the attractancy potential of metabolites produced by gut microbial community of B. zonata in open field condition. This study results may prompt the development of a female-targeted population control strategy for this fly. [ABSTRACT FROM AUTHOR]

Peach gummosis, caused by Lasiodiplodia theobromae, is one of the most prevalent diseases that affects peach production. In this study, we investigated the effect of zinc sulfate on inoculated peach shoots, as well as on the growth, morphology, and pathogenicity of L. theobromae in vitro, in the laboratory. Zinc deficiency was detected in diseased peach shoots by micronutrient analysis (Cu, Mn, and Zn) and confirmed by the measurement of transcript levels of zinc transporters (ZIP4, HAM4, and ZAT). The zinc was transferred from the diseased peach shoots to the peach gum. Applying zinc sulfate to the diseased peach shoots reduced the severity of peach gummosis, showing significantly reduced lesion size and gum weight, as well as downregulation of cell wall degradation-related gene (PG and PME) compared with the control. Zinc sulfate also specifically controlled peach gummosis under L. theobromae phytotoxin stress and induced the expression of defense-related genes (PR4, CHI, PAL, PGIP, and GNS3). In addition, in vitro mycelial growth of L. theobromae was significantly inhibited by zinc sulfate compared with the control. Zinc sulfate caused abnormal hyphae at 25 mM and swelling hyphal tips at 50 mM. Exposure of L. theobromae to zinc sulfate for 20 min inhibited the ability of the pathogen to cause peach gummosis. Our physiological and molecular data demonstrated that zinc sulfate has a dual function by reducing susceptibility in the host and by direct inhibition of the pathogen. [ABSTRACT FROM AUTHOR]

Peaches in cold storage may develop chill damage, as symptomized by deteriorated texture and lack of juice. To examine fruit quality, we established a hyperspectral imaging system to detect cold injury, and an artificial neural network (ANN) model was developed for which eight optimal wavelengths were selected. Between normal and chill-damaged peaches, significant differences in fruit quality parameters and the spectral response to correlating selected wavelengths were observed. Evidencing this relationship, the correlation coefficients between quality parameters and the respective spectral response of eight selected wavelengths were −0.587 to −0.700, 0.393 to 0.552, 0.510 to 0.751, and 0.574 to 0.773. With optimal representative wavelengths as inputs for the ANN model, the overall classification accuracy of chill damage was 95.8% for all cold-stored samples. The ANN prediction models for quality parameters performed well, with correlation coefficients from 0.6979 to 0.9026. This research demonstrates feasibility of hyperspectral reflectance imaging technique for detecting cold injury. [ABSTRACT FROM AUTHOR]

For control of the Mediterranean fruit fly Ceratitis capitata ( Diptera: Tephritidae), the attract-and-kill or attracticide technique is an alternative to the spraying of traditional organophosphate pesticides. In this study, the effectiveness of Ceranock and AAL& K attract-and-kill bait stations was assessed for control of C. capitata in Tunisian peach ( Prunus persica) orchards. Our results showed that, in orchards with early-ripening varieties, the numbers of C. capitata males and fruit damage were significantly lower in plots treated with Ceranock and AAL& K bait stations than in plots treated with conventional organophosphate and pyrethroid insecticides. In addition, the abundances of non-target insects in the Chrysopidae, Coccinellidae and Miridae were significantly greater in plots treated with the bait stations than in plots treated with the conventional pesticides; that is, the use of attract-and-kill bait stations had fewer negative effects than the application of conventional pesticides on the biological diversity in Tunisian peach orchards. Overall, the results indicate that Ceranock and AAL& K attract-and-kill bait stations are useful alternatives for the control of C. capitata in Tunisian peach orchards planted with early-ripening varieties. [ABSTRACT FROM AUTHOR]

Fruit skin defects may cause fruit spoilage, reduce commodity economic value, and give rise to food quality and safety concerns. Therefore, one of the main tasks of post-harvest processing of fruit is the detection of skin defects by machine vision technology. However, inspection of skin defects on bi-colored fruit varieties by image processing is more difficult because of the high variability of the skin color. This article presents a multispectral detection method for skin defects of bi-colored ‘Pinggu’ peaches based on visible-near infrared (vis–NIR) hyperspectral imaging. Peaches with nine types of skin condition including skin injury, scarring, insect damage, puncture injury, decay, disease spots, dehiscent scarring and anthracnose and normal surface were studied. Principal component analysis (PCA) was used to reduce hyperspectral data dimensionality to select several wavelengths that could potentially be used in an in-line multispectral imaging system. Different defect types produced an obvious feature only in some specific PC images depending on whether the visible light spectrum (425–780 nm), the near infrared spectrum (781–1000 nm), the full-spectrum (400–1000 nm) or only characteristic wavelengths (463, 555, 687, 712, 813, 970 nm or 781, 815, 848 nm) were used. A two-band ratio image ( Q 781/848 ) was successfully used to differentiate defects from a normal surface. Finally, a detection algorithm for skin defects was developed based on a band ratio ( Q 781/848 ) coupled with a simple thresholding method. For the investigated 145 independent test samples with nine skin conditions, an accuracy of 96.6% was obtained, indicating that the proposed multispectral algorithm was effective in differentiating normal and defective bi-colored peaches. The proposed algorithm can be extended to other fruit. [ABSTRACT FROM AUTHOR]