Summary
The fungal pathogen Botrytis cinerea causes grey mould, a commercially damaging disease of strawberry. This pathogen affects fruit in the field, storage, transport and market. The presence of ...grey mould is the most common reason for fruit rejection by growers, shippers and consumers, leading to significant economic losses. Here, we review the biology and epidemiology of the pathogen, mechanisms of infection and the genetics of host plant resistance. The development of grey mould is affected by environmental and genetic factors; however, little is known about how B. cinerea and strawberry interact at the molecular level. Despite intensive efforts, breeding strawberry for resistance to grey mould has not been successful, and the mechanisms underlying tolerance to B. cinerea are poorly understood and under‐investigated. Current control strategies against grey mould include pre‐ and postharvest fungicides, yet they are generally ineffective and expensive. In this review, we examine available research on horticultural management, chemical and biological control of the pathogen in the field and postharvest storage, and discuss their relevance for integrative disease management. Additionally, we identify and propose approaches for increasing resistance to B. cinerea in strawberry by tapping into natural genetic variation and manipulating host factors via genetic engineering and genome editing.
Fruit development is a complex process that is regulated not only by plant hormones and transcription factors, but also requires epigenetic modifications. Epigenetic modifications include DNA ...methylation, histone post-translational modifications, chromatin remodeling and noncoding RNAs. Together, these epigenetic modifications, which are controlled during development and in response to the environment, determine the chromatin state of genes and contribute to the transcriptomes of an organism. Recent studies have demonstrated that epigenetic regulation plays an important role in fleshy fruit ripening. Dysfunction of a DNA demethylase delayed ripening in tomato, and the application of a DNA methylation inhibitor altered ripening process in the fruits of several species. These studies indicated that manipulating the epigenome of fruit crops could open new ways for breeding in the future. In this review, we highlight recent progress and address remaining questions and challenges concerning the epigenetic regulation of fruit development and ripening.
Fleshy fruit undergo a novel developmental program that ends in the irreversible process of ripening and eventual tissue senescence. During this maturation process, fruit undergo numerous ...physiological, biochemical and structural alterations, making them more attractive to seed dispersal organisms. In addition, advanced or over-ripening and senescence, especially through tissue softening and eventual decay, render fruit susceptible to invasion by opportunistic pathogens. While ripening and senescence are often used interchangeably, the specific metabolic activities of each would suggest that ripening is a distinct process of fleshy fruits that precedes and may predispose the fruit to subsequent senescence.
BackgroundOne of the main factors that reduce fruit quality and lead to economically important losses is oversoftening. Textural changes during fruit ripening are mainly due to the dissolution of the ...middle lamella, the reduction of cell-to-cell adhesion and the weakening of parenchyma cell walls as a result of the action of cell wall modifying enzymes. Pectins, major components of fruit cell walls, are extensively modified during ripening. These changes include solubilization, depolymerization and the loss of neutral side chains. Recent evidence in strawberry and apple, fruits with a soft or crisp texture at ripening, suggests that pectin disassembly is a key factor in textural changes. In both these fruits, softening was reduced as result of antisense downregulation of polygalacturonase genes. Changes in pectic polymer size, composition and structure have traditionally been studied by conventional techniques, most of them relying on bulk analysis of a population of polysaccharides, and studies focusing on modifications at the nanostructural level are scarce. Atomic force microscopy (AFM) allows the study of individual polymers at high magnification and with minimal sample preparation; however, AFM has rarely been employed to analyse pectin disassembly during fruit ripening.ScopeIn this review, the main features of the pectin disassembly process during fruit ripening are first discussed, and then the nanostructural characterization of fruit pectins by AFM and its relationship with texture and postharvest fruit shelf life is reviewed. In general, fruit pectins are visualized under AFM as linear chains, a few of which show long branches, and aggregates. Number- and weight-average values obtained from these images are in good agreement with chromatographic analyses. Most AFM studies indicate reductions in the length of individual pectin chains and the frequency of aggregates as the fruits ripen. Pectins extracted with sodium carbonate, supposedly located within the primary cell wall, are the most affected.
Human selection has reshaped crop genomes. Here we report an apple genome variation map generated through genome sequencing of 117 diverse accessions. A comprehensive model of apple speciation and ...domestication along the Silk Road is proposed based on evidence from diverse genomic analyses. Cultivated apples likely originate from Malus sieversii in Kazakhstan, followed by intensive introgressions from M. sylvestris. M. sieversii in Xinjiang of China turns out to be an "ancient" isolated ecotype not directly contributing to apple domestication. We have identified selective sweeps underlying quantitative trait loci/genes of important fruit quality traits including fruit texture and flavor, and provide evidences supporting a model of apple fruit size evolution comprising two major events with one occurring prior to domestication and the other during domestication. This study outlines the genetic basis of apple domestication and evolution, and provides valuable information for facilitating marker-assisted breeding and apple improvement.Apple is one of the most important fruit crops. Here, the authors perform deep genome resequencing of 117 diverse accessions and reveal comprehensive models of apple origin, speciation, domestication, and fruit size evolution as well as candidate genes associated with important agronomic traits.
Fruits produce a wide range of volatile organic compounds that impart their characteristically distinct aromas and contribute to unique flavor characteristics. Fruit aroma and flavor characteristics ...are of key importance in determining consumer acceptance in commercial fruit markets based on individual preference. Fruit producers, suppliers and retailers traditionally utilize and rely on human testers or panels to evaluate fruit quality and aroma characters for assessing fruit salability in fresh markets. We explore the current and potential utilization of electronic-nose devices (with specialized sensor arrays), instruments that are very effective in discriminating complex mixtures of fruit volatiles, as new effective tools for more efficient fruit aroma analyses to replace conventional expensive methods used in fruit aroma assessments. We review the chemical nature of fruit volatiles during all stages of the agro-fruit production process, describe some of the more important applications that electronic nose (e-nose) technologies have provided for fruit aroma characterizations, and summarize recent research providing e-nose data on the effectiveness of these specialized gas-sensing instruments for fruit identifications, cultivar discriminations, ripeness assessments and fruit grading for assuring fruit quality in commercial markets.
•A single foliar spray with relatively low amounts of B or Zn nano-fertilizers (34mgBtree−1 or 636mgZntree−1, respectively) led to increases in pomegranate fruit yield.•Fertilization with the highest ...of the two doses led to significant improvements in fruit quality, including TSS, decreases in TA, and increases in maturity index and pH in juice.•Physical fruit characteristics were unaffected. Changes in total sugars and total phenolic compounds were only minor, whereas the antioxidant activity and total anthocyanin were unaffected.
This study was carried out to assess the effects of the foliar application of nano-fertilizers of zinc (Zn) and boron (B) on pomegranate (Punica granatum cv. Ardestani) fruit yield and quality. A factorial experiment was conducted based on a completely randomized block design, with nine treatments and four replications per treatment. Foliar sprays of nano-Zn chelate fertiliser at three concentrations (0, 60 and 120mgZnL−1) and nano-B chelate fertiliser (0, 3.25 and 6.5mgBL−1) were applied as a single spray before full bloom at a rate of 5.3Ltree−1. The application of Zn and B increased the leaf concentrations of both microelements in August, reflecting the improvements in tree nutrient status. A single foliar spray with relatively low amounts of B or Zn nano-fertilizers (34mgBtree−1 or 636mgZntree−1, respectively) led to increases in pomegranate fruit yield, and this was mainly due to increases in the number of fruits per tree. The effect was not as large with Zn as with B. Fertilization with the highest of the two doses led to significant improvements in fruit quality, including 4.4–7.6% increases in TSS, 9.5–29.1% decreases in TA, 20.6–46.1% increases in maturity index and 0.28–0.62pH unit increases in juice pH, whereas physical fruit characteristics were unaffected. Changes in total sugars and total phenolic compounds were only minor, whereas the antioxidant activity and total anthocyanins were unaffected.
This review highlights the increasing importance of fruits as model experimental systems to explore the diversity of cuticle composition, architecture, and functions.
Variation in cucumber (Cucumis sativus L.) fruit size and shape is highly quantitative, implicating interplay of multiple components. Recent studies have identified numerous fruit size and shape ...quantitative trait loci (QTL); however, underlying factors remain to be determined. We examined ovary and fruit development of two sequenced cucumber genotypes with extreme differences in fruit size and shape, Chinese Long ‘9930’ (CL9930), and pickling type ‘Gy14’. Differences were observed in several independent factors that can influence size and shape: ovule number, rate and period of cell division in longitudinal and cross section in ovaries and fruit, timing and rate of fruit expansion in length and diameter, and cell shape. Level and timing of expression of select fruit growth stage marker genes and candidate fruit size gene homologs associated with cucumber fruit size and shape QTL were examined from 5-day pre-anthesis to 20-day post-pollination. Our results indicate that variation in fruit size and shape results from differences in cell number and shape in longitudinal and cross section, driven in turn by differences in orientation, timing, and duration of cell division and expansion, both pre- and post-anthesis, and suggest candidate genes contributing to determination of cucumber fruit size and shape.
Maturity is the most important and complex stage in the development of the fruit, where they acquire sensory characteristics that define it as edible. The objective of this research is to determine ...the color indices associated with the different stages of maturation of the pumpkin fruit (Carica papaya L, variety MaradolRoja), guava (Psidiumguajava L, variety EnanaRoja EEA1-23) and tomato (Solanumlycopersicum, variety Vyta). To carry out the study, 32 pumpkins and 40 guava fruits were used. Fruits pumpkin and guava, were harvested in the Agricultural Company Ho Chi Minh, in the municipality of Jaruco, and tomato in the farm "The Papas" belonging to the National Institute of Agricultural Sciences (INCA), located in the municipality from San José de lasLajas, Mayabeque. The chemical, physical-mechanical and organoleptic properties were monitored in the different stages of maturation. In addition, the fruits were photographed and the images were analyzed to obtain the color indexes in the different stages of maturation. Finally, for the pump fruit and the tomato, four ripening stages and five for the guava are defined, in addition to the ranges of the color index associated with each one of them.
PDF
