Fruit Development

Fruit and vegetables have many similarities with respect to their compositions, methods of cultivation and harvesting, storage properties and processing.In reference to fruits and vegetables, the characteristics that impart distinctive quality may be described by four different attributes -1) color and appearance, 2) flavor (taste and aroma), 3) texture and 4) nutritional value.

Capsicum species commonly known as Chilli pepper is one of the world's most important vegetable and spice crop. India is the world's largest producer, consumer and exporter of chilli pepper. Despite comprising 38 species, only six species of Capsicum namely, Capsicum annuum, C. assamicum, C. baccatum, C. frutescence, C. chinense and C. pubescens are cultivated. They are used as vegetables, spices, coloring agent and folk remedies (for diseases), proving their diverse role in human's life. Chilli pepper in mainly known for its pungency characteristics. The presence of capsaicinoids, a pungency character classifies pepper into sweet peppers and hot peppers. The molecular markers, quantitative trait loci developed by conventional breeding and classical genetic analysis have revealed number of genes for major and important traits. While, the newly developed next generation sequencing and genotyping technologies have been able to generate large scale genomic resources and to find the molecular basis of economically important traits in Capsicum genome. This chapter summarizes the advances in genomics and their applications in the form of generation of resources, comparative mapping, and identification of candidate genes for fruit trait, pungency, male sterility, disease resistance, viral resistance, nematode resistance and abiotic stress tolerance. In summary, we propose the integrated use of genomics and breeding approach in Capsicum translational research to enhance the crop productivity.

In the present work, the effect of assisted fertilization on anatomical, morphological and gene expression changes occurring in carpels and during early stages of berry development in Vitis vinifera were studied. Inflorescences were emasculated before capfall, immediately manually pollinated (EP) and fruit development was compared to emasculated but non-pollinated (ENP) and self-pollinated inflorescences (NESP). The diameter of berries derived from pollinated flowers (EP and NESP) was significantly higher than from non-pollinated flowers (ENP) at 21 days after emasculation/pollination (DAE), and a rapid increase in the size of the inner mesocarp, together with the presence of an embryo-like structure, were observed. The expression of gibberellin oxidases (GA20ox and GA2ox), anthranilate synthase (related to auxin synthesis) and cytokinin synthase coding genes was studied to assess the relationship between hormone synthesis and early berry development, while flower patterning genes w...

Plant MADS-box genes encode transcriptional regulators that are critical for a number of developmental processes, such as the establishment of floral organ identity, flowering time, and fruit development. It appears that the MADS-box gene family has undergone considerable gene duplication and divergence within various angiosperm lineages. SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1)/Tomato MADS-box gene 3 (TM3)-like genes are members of the MADS-box gene family and have undergone repeated duplication events. Here, we isolated and characterized the SOC1/TM3-like gene TrcMADS1 from Trillium camtschatcense (Trilliaceae) to infer the ancestral function of SOC1/TM3-like genes. The alignment of SOC1/TM3-like genes revealed the presence of a highly conserved region in the C-terminal of predicted protein sequences, designated the SOC1 motif. Phylogenetic analysis indicated that TrcMADS1 is at the basal position of the SOC1/TM3-like gene family. The TrcMADS1 mRNA was detected in both vegetative and reproductive organs by RT-PCR. Our results suggest that duplicated copies of SOC1/TM3-like gene evolved to become variously functionally specialized.

Background Field observations and a few physiological studies have demonstrated that peach embryogenesis and fruit development are tightly coupled. In fact, attempts to stimulate parthenocarpic fruit development by means of external tools have failed. Moreover, physiological disturbances during early embryo development lead to seed abortion and fruitlet abscission. Later in embryo development, the interactions between seed and fruit development become less strict. As there is limited genetic and molecular information about seed-pericarp cross-talk and development in peach, a massive gene approach based on the use of the μPEACH 1.0 array platform and quantitative real time RT-PCR (qRT-PCR) was used to study this process. Results A comparative analysis of the transcription profiles conducted in seed and mesocarp (cv Fantasia) throughout different developmental stages (S1, S2, S3 and S4) evidenced that 455 genes are differentially expressed in seed and fruit. Among differentially expre...

Background In the past few years, functional genomics information has been rapidly accumulating on Rubiaceae species and especially on those belonging to the Coffea genus (coffee trees). An increasing number of expressed sequence tag (EST) data and EST- or genomic-derived microsatellite markers have been generated, together with Conserved Ortholog Set (COS) markers. This considerably facilitates comparative genomics or map-based genetic studies through the common use of orthologous loci across different species. Similar genomic information is available for e.g. tomato or potato, members of the Solanaceae family. Since both Rubiaceae and Solanaceae belong to the Euasterids I (lamiids) integration of information on genetic markers would be possible and lead to more efficient analyses and discovery of key loci involved in important traits such as fruit development, quality, and maturation, or adaptation. Our goal was to develop a comprehensive web data source for integrated information...

Sugar content, aroma and texture are key quality traits that influence consumer preference of many fruits and vegetables such as muskmelon (Cucumis melo L. (Reticulatus Group)). These quality traits are directly related to potassium (K)-mediated processes. However, soil-derived K alone is seldom adequate to satisfy these fruit quality processes. Controlled environment studies have shown that supplemental foliar K applications can overcome this apparent deficiency. However, the suitability of potential K salts as foliar sources is still uncertain. We evaluated six foliar K sources (potassium chloride - KCl, potassium nitrate - KNO3, monopotassium phosphate - MKP, potassium sulfate - K2SO4, potassium thiosulfate - KTS , and a glycine amino acid-complexed K- Potassium Metalosate, KM) for effects on fruit quality parameters of field- grown muskmelon 'Cruiser' over two growing seasons, 2006 and 2007 in Weslaco, south Texas. Weekly foliar K applications were initiated at fruit s...

Changes in soluble sugar and starch reserves in avocado (Persea americana Mill. on `Duke 7' rootstock) fruit were followed during growth and development and during low temperature storage and ripening. During the period of rapid fruit size expansion, soluble sugars accounted for most of the increase in fruit tissue biomass (peel: 17% to 22%, flesh: 40% to 44%, seed: 32% to 41% of the dry weight). More than half of the fruit total soluble sugars (TSS) was comprised of the seven carbon (C7) heptose sugar, D-mannoheptulose, and its polyol form, perseitol, with the balance being accounted for by the more common hexose sugars, glucose and fructose. Sugar content in the flesh tissues declined sharply as oil accumulation commenced. TSS declines in the seed were accompanied by a large accumulation of starch (≈30% of the dry weight). During postharvest storage at 1 or 5 °C, TSS in peel and flesh tissues declined slowly over the storage period. Substantial decreases in TSS, and especially...

Fruitlet abscission during fruit development is due to the activation ofpre-differentiated abscission zones (AZs) located between twig andpedicel, and/or pedicel and pericarp. Major advances on biochemicaland molecular aspects are related to β-1,4-endoglucanase (EG) andpolygalacturonase (PG), two cell hydrolases involved in the cell walldisassemblement responsible for fruit shedding. AZ activation isaccompanied by an increase in activity and transcript accumulation ofone or both enzymes. Expression of PG genes specifically related toabscission has been found in tomato flower AZ. In peach, an EG genehighly expressed in leaf and fruitlet AZs has been isolated. AZactivation is preceded by an induction of ethylene biosynthesis,paralleled by a stimulation of ACO activity and transcript accumulation.Ethylene, besides a dramatic stimulation of PG and EG, up or downregulates several other abscission related genes. The specificexpression of genes encoding for ethylene receptors in the AZ wouldsupport the hypothesis that fruitlet AZ specificity may depend on theability of this region to sense ethylene.

The class of cell wall polysaccharides that undergoes the most extensive modification during tomato (Lycopersicon esculentum) fruit ripening is pectin. De-esterification of the polygalacturonic acid backbone by pectin methylesterase facilitates the depolymerization of pectins by polygalacturonase II (PGII). To investigate the spatial aspects of the de-esterification of cell wall pectins and the subsequent deposition of PGII, we have used antibodies to relatively methylesterified and nonesterified pectic epitopes and to the PGII protein on thin sections of pericarp tissue at different developmental stages. De-esterification of pectins and deposition of PGII protein occur in block-like domains within the cell wall. The boundaries of these domains are distinct and persistent, implying strict, spatial regulation of enzymic activities. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins strongly associated with cell walls of pericarp tissue at each stage of fruit develo...

• Plant hormones are considered to be important mediators of the fruit developmental signal after pollination. The role of phytohormones in tomato (Solanum lycopersicum) fruit set was investigated here.• Transcriptome analysis of ovaries was performed using two complementary approaches: cDNA–amplified fragment length polymorphism (AFLP) and microarray analysis.• The gene expression profiles obtained suggest that, in addition to auxin and gibberellin, ethylene and abscisic acid (ABA) are involved in regulating fruit set. Before fruit development, many genes involved in biotic and abiotic responses are active in the ovary. In addition, genes involved in ethylene and ABA biosynthesis were strongly expressed, suggesting relatively high ethylene and ABA concentrations before fruit set. Induction of fruit development, either by pollination or by gibberellin application, attenuated expression of all ethylene and ABA biosynthesis and response genes within 24 h.• It is proposed that the function of ABA and ethylene in fruit set might be antagonistic to that of auxin and gibberellin in order to keep the ovary in a temporally protected and dormant state; either to protect the ovary tissue or to prevent fruit development before pollination and fertilization occur.Plant hormones are considered to be important mediators of the fruit developmental signal after pollination. The role of phytohormones in tomato (Solanum lycopersicum) fruit set was investigated here.Transcriptome analysis of ovaries was performed using two complementary approaches: cDNA–amplified fragment length polymorphism (AFLP) and microarray analysis.The gene expression profiles obtained suggest that, in addition to auxin and gibberellin, ethylene and abscisic acid (ABA) are involved in regulating fruit set. Before fruit development, many genes involved in biotic and abiotic responses are active in the ovary. In addition, genes involved in ethylene and ABA biosynthesis were strongly expressed, suggesting relatively high ethylene and ABA concentrations before fruit set. Induction of fruit development, either by pollination or by gibberellin application, attenuated expression of all ethylene and ABA biosynthesis and response genes within 24 h.It is proposed that the function of ABA and ethylene in fruit set might be antagonistic to that of auxin and gibberellin in order to keep the ovary in a temporally protected and dormant state; either to protect the ovary tissue or to prevent fruit development before pollination and fertilization occur.

By the use of two distinct algorithms, implemented by geNorm and NormFinder, we have assessed the gene expression of nine candidate reference genes in cotton: GhACT4, GhEF1α5, GhFBX6, GhPP2A1, GhMZA, GhPTB, GhGAPC2, GhβTUB3 and GhUBQ14. The ...

Muskmelon [Cucumis melo L. (Reticulatus Group)] fruit sugar content is directly related to potassium (K)-mediated phloem transport of sucrose into the fruit. However, during fruit growth and maturation, soil fertilization alone is often inadequate (due to poor root uptake and competitive uptake inhibition from calcium and magnesium) to satisfy the numerous K-dependent processes, such as photosynthesis, phloem transport, and fruit growth. Experiments were conducted during Spring 2003 and 2004 to determine if supplemental foliar K applications during the fruit growth and maturation period would alleviate this apparent inadequate K availability in orange-flesh muskmelon `Cruiser'. Plants were grown in a greenhouse and fertilized throughout the study with a soil-applied N-P-K fertilizer. Flowers were hand pollinated and only one fruit per plant was allowed to develop. Starting at 3 to 5 days after fruit set, and up to 3 to 5 days prior to fruit maturity (full slip), entire plants, i...

Field experiments were conducted in 2005 on orange, Citrus sinensis (L.) Osbeck, var. Thomson in two different sites, Sbikha and Sidi Bouali, in Tunisia to assess the effectiveness of kaolin, spinosad and malathion against the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera Tephritidae). In both study sites, the materials were applied 3 times (kaolin at a concen-tration of 5 kg formulated product /100 l, spinosad at a concentration of 1 l formulated product /ha and malathion at a concentra-tion of 200 ml formulated product /100 l). The efficacy of the different treatments was evaluated by assessing male captures in modified Steiner traps and fruit damage (punctured and dropped fruits). The results indicated that (1) no significant differences among treatments in male captures were detected (2) fruit damage (no. punctured fruits and fallen fruits) was lower on kaolin-treated trees than on spinosad, malathion, and untreated trees. Kaolin suc-cessfully protect...