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The effects of different fruit load treatments during peach growth and development on the internal and external quality of peach fruit were studied. At 47 days after full bloom, the plant materials were divided into four treatments: about 100%, 75%, 50% and 25% of fruit were retained. The results showed that as the fruit load was reduced during fruit growth and development, the fruit weight, size, soluble solid contents (SSC), total sugar content, sugar/acid ratio and color quality increased, while the flesh firmness, index of absorbance difference (IAD) and total acid content decreased. Compared with the control treatment in which the fruit were not thinned, the weight of individual mature fruit increased by 24.52%, 39.73% and 51.68% under three fruit thinning treatments (in which about 75%, 50% and 25% of the fruit were left on the tree). SSC increased by 30.78%, 37.63% and 49.69%; total sugar content increased by 13.58%, 22.33% and 31.42%; and the sugar-acid ratio increased by 13.25%, 13.59% and 19.47%, respectively, under the three conditions. In addition, the longitudinal, transverse and lateral diameters of fruit increased to varying degrees when the fruit load was reduced. Furthermore, the fruit firmness and IAD value of fruit skins decreased, and fruit ripening was advanced when the fruit load was reduced. The results showed that fruit quality and flavor were improved significantly by fruit thinning. [ABSTRACT FROM AUTHOR]

To investigate how sodium selenite (Na2SeO3) regulated the content of vitamin C (Vc) in strawberry fruit, we explored the effects of Na2SeO3 on the enzymes responsible for Vc metabolism. The findings showed that 10 mg/L Na2SeO3 improved the activities of ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), l-galactono-1,4-lactone dehydrogenase (GalLDH) at periods of young fruit (YFP), small fruit (SFP), middle fruit (MFP), large fruit (LFP), white fruit (WFP), colour-changed fruit (CFP) and ripen fruit (RFP). 30 mg/L Na2SeO3 improved the activities of APX, MDHAR, GR and GaILDH at YFP, LFP, WFP, CFP and RFP. 60 mg/L Na2SeO3 improved the activities of MDHAR, GR and GaILDH at all periods studied. In addition, 10 mg/L Na2SeO3 decreased the activity of ascorbate oxidase (AAO) at WFP and CFP. 30 mg/L Na2SeO3 decreased AAO activity at MFP, LFP, WFP and CFP. 60 mg/L Na2SeO3 decreased AAO activity at YFP, SFP, MFP, LFP, WFP and CFP. Meanwhile, all concentrations of Na2SeO3 significantly increased the contents of Vc and Se. Among different concentrations, 30 mg/L Na2SeO3 had better effects on the enzymes responsible for Vc metabolism, which further improved Vc content in strawberry fruit. Besides, all concentrations of Na2SeO3 increased fruit average weight, number of fruits per plant and fruit yield, compared with control. The above results indicated that Na2SeO3 could improve the content of Vc in fruit and fruit yield of strawberries, especially for 30 mg/L Na2SeO3.

The effects of different fruit load treatments during peach growth and development on the internal and external quality of peach fruit were studied. At 47 days after full bloom, the plant materials were divided into four treatments: about 100%, 75%, 50% and 25% of fruit were retained. The results showed that as the fruit load was reduced during fruit growth and development, the fruit weight, size, soluble solid contents (SSC), total sugar content, sugar/acid ratio and color quality increased, while the flesh firmness, index of absorbance difference (IAD) and total acid content decreased. Compared with the control treatment in which the fruit were not thinned, the weight of individual mature fruit increased by 24.52%, 39.73% and 51.68% under three fruit thinning treatments (in which about 75%, 50% and 25% of the fruit were left on the tree). SSC increased by 30.78%, 37.63% and 49.69%; total sugar content increased by 13.58%, 22.33% and 31.42%; and the sugar-acid ratio increased by 13.25%, 13.59% and 19.47%, respectively, under the three conditions. In addition, the longitudinal, transverse and lateral diameters of fruit increased to varying degrees when the fruit load was reduced. Furthermore, the fruit firmness and IAD value of fruit skins decreased, and fruit ripening was advanced when the fruit load was reduced. The results showed that fruit quality and flavor were improved significantly by fruit thinning.

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Vegetable crops have a long history of cultivation worldwide and rich germplasm resources. With its continuous development and progress, molecular biology technology has been applied to various fields of vegetable crop research. Fruit is an important organ in vegetable crops, and fruit shape can affect the yield and commercialization of vegetables. In nature, fruits show differences in size and shape. Based on fruit shape diversity, the growth direction and coordination mechanism of fruits remain unclear. In this review, we discuss the latest research on fruit shape. In addition, we compare the current theories on the molecular mechanisms that regulate fruit growth, size, and shape in different vegetable families. [ABSTRACT FROM AUTHOR]

Abstract Background Expansins (EXPs) facilitate non-enzymatic cell wall loosening during several phases of plant growth and development including fruit growth, internode expansion, pollen tube growth, leaf and root development, and during abiotic stress responses. In this study, the spatial and temporal expression patterns of C. annuum α- EXPANSIN (CaEXPA) genes were characterized. Additionally, fruit-specific CaEXPA expression was correlated with the rate of cell expansion during bell pepper fruit development. Results Spatial expression patterns revealed that CaEXPA13 was up-regulated in vegetative tissues and flowers, with the most abundant expression in mature leaves. Expression of CaEXPA4 was associated with stems and roots. CaEXPA3 was expressed abundantly in flower at anthesis suggesting a role for CaEXPA3 in flower development. Temporal expression analysis revealed that 9 out of the 21 genes were highly expressed during fruit development. Of these, expression of six genes, CaEXPA5, CaEXPA7, CaEXPA12, CaEXPA14 CaEXPA17 and CaEXPA19 were abundant 7 to 21 days after anthesis (DAA), whereas CaEXPA6 was strongly expressed between 14 and 28 DAA. Further, this study revealed that fruit growth and cell expansion occur throughout bell pepper development until ripening, with highest rates of fruit growth and cell expansion occurring between 7 and 14 DAA. The expression of CaEXPA14 and CaEXPA19 positively correlated with the rate of cell expansion, suggesting their role in post-mitotic cell expansion-mediated growth of the bell pepper fruit. In this study, a ripening specific EXP transcript, CaEXPA9 was identified, suggesting its role in cell wall disassembly during ripening. Conclusions This is the first genome-wide study of CaEXPA expression during fruit growth and development. Identification of fruit-specific EXPAs suggest their importance in facilitating cell expansion during growth and cell wall loosening during ripening in bell pepper. These EXPA genes could be important targets for future manipulation of fruit size and ripening characteristics.

Abstract Background The major fleshy tissues of the apple fruit are spatially separable into cortex and pith. These tissues display differential growth during development. Key features of such differential growth, and sink metabolic programs supporting it have not been investigated previously. We hypothesized that differential growth between these fruit tissues is supported by differential sink metabolic programs, particularly during early development. Growth, metabolite concentrations, and transcript abundance of metabolism-related genes were measured to determine characteristics of differential growth and their underlying metabolic programs. Results The cortex displayed > 5-fold higher growth than the pith during early fruit development, indicating that differential growth was established during this period. Further, when resource availability was increased through sink-removal, cortex growth was preferentially enhanced. Greatest diversity in metabolic programs between these tissues was evident during early fruit development. Higher cortex growth during early development was facilitated by increased catabolism of imported carbon (C) resources, sorbitol and sucrose, and the nitrogen (N) resource, asparagine. It was also associated with enhanced primary C metabolism, and C storage as malate and quinate. The pith metabolic program during this period involved limited allocation of C and N to growth, but greater allocation to storage, and enhanced sucrose-sucrose cycling. Conclusions Together, these data indicate that the fruit cortex tissue displays a resource intensive metabolic program during early fruit development. This provides the C backbones, proteins, energy and osmolytes to support its higher growth.

Agricultural practices in grapevines management include water restrictions due to its positive effect on wine quality, especially when applied at fruit ripening. Although the effects of water stress in some groups of phytohormones have already been described in leaves and whole grapes, information regarding tissue-specific variations in hormones during ripening in grapes is scarce. Field-grown grapevines from the cv. “Merlot” were subjected to two differential water supplies, including only rainfed, non-irrigated vines (T0) and vines additionally irrigated with 25Lweek−1 vine−1 (T1). Tissue-specific variations in the hormonal profiling of grapes [including changes in the contents of abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), the ethylene precursor 1-amino-cyclopropane-1-carboxylic acid (ACC), the auxin indole-3-acetic acid, gibberellins 1, 3, 4, and 7 (GA1, GA3, GA4, and GA7), the cytokinins trans-zeatin, and 2-isopentenyl adenine, including as well their respective ribosylated forms] were periodically evaluated from veraison to harvest. The hormonal profiling in leaves was also measured at the beginning and end of the season for comparison. Results showed that grape growth dynamics were transiently affected by the differences in water regimes, the increased water supply leading to an accelerated growth, slightly reduced accumulation of sugars, and transiently lowered pH, although grape quality did not differ between treatments at harvest. Hormonal profiling of whole berries did not reveal any difference in the endogenous contents of phytohormones between treatments, except for a transient decrease in GA4 contents in T1 compared to T0 vines, which was not confirmed at the tissular level. Hormonal profiling at the tissue level highlighted a differential accumulation of phytohormones during ripening in berry tissues, with pulps being particularly poor in ABA, JA, and SA contents, seeds particularly accumulating ACC, gibberellins, and zeatin-type cytokinins, and the skin being particularly rich in auxin and active cytokinins. Changes in water supply led to very small and transient changes in the endogenous contents of phytohormones in the seeds, pulp, and skin of berries, the most remarkable variations being observed in cytokinin contents, which increased earlier [between 5 and 12days after veraison (DAV)] but later kept more constant in the skin from T1 compared to T0 vines and were also 3-fold higher at 40 DAV in seeds of T1 compared to T0 vines. It is concluded that small changes in water supply can trigger hormonal-driven physiological adjustments at the tissular level affecting the evolution of fruit growth and quality throughout grape berry ripening.

Agricultural practices in grapevines management include water restrictions due to its positive effect on wine quality, especially when applied at fruit ripening. Although the effects of water stress in some groups of phytohormones have already been described in leaves and whole grapes, information regarding tissue-specific variations in hormones during ripening in grapes is scarce. Field-grown grapevines from the cv. "Merlot" were subjected to two differential water supplies, including only rainfed, non-irrigated vines (T0) and vines additionally irrigated with 25Lweek−1 vine−1 (T1). Tissue-specific variations in the hormonal profiling of grapes [including changes in the contents of abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), the ethylene precursor 1-amino-cyclopropane-1-carboxylic acid (ACC), the auxin indole-3-acetic acid, gibberellins 1, 3, 4, and 7 (GA1, GA3, GA4, and GA7), the cytokinins trans -zeatin, and 2-isopentenyl adenine, including as well their respective ribosylated forms] were periodically evaluated from veraison to harvest. The hormonal profiling in leaves was also measured at the beginning and end of the season for comparison. Results showed that grape growth dynamics were transiently affected by the differences in water regimes, the increased water supply leading to an accelerated growth, slightly reduced accumulation of sugars, and transiently lowered pH, although grape quality did not differ between treatments at harvest. Hormonal profiling of whole berries did not reveal any difference in the endogenous contents of phytohormones between treatments, except for a transient decrease in GA4 contents in T1 compared to T0 vines, which was not confirmed at the tissular level. Hormonal profiling at the tissue level highlighted a differential accumulation of phytohormones during ripening in berry tissues, with pulps being particularly poor in ABA, JA, and SA contents, seeds particularly accumulating ACC, gibberellins, and zeatin-type cytokinins, and the skin being particularly rich in auxin and active cytokinins. Changes in water supply led to very small and transient changes in the endogenous contents of phytohormones in the seeds, pulp, and skin of berries, the most remarkable variations being observed in cytokinin contents, which increased earlier [between 5 and 12days after veraison (DAV)] but later kept more constant in the skin from T1 compared to T0 vines and were also 3-fold higher at 40 DAV in seeds of T1 compared to T0 vines. It is concluded that small changes in water supply can trigger hormonal-driven physiological adjustments at the tissular level affecting the evolution of fruit growth and quality throughout grape berry ripening. [ABSTRACT FROM AUTHOR]

Vegetable crops have a long history of cultivation worldwide and rich germplasm resources. With its continuous development and progress, molecular biology technology has been applied to various fields of vegetable crop research. Fruit is an important organ in vegetable crops, and fruit shape can affect the yield and commercialization of vegetables. In nature, fruits show differences in size and shape. Based on fruit shape diversity, the growth direction and coordination mechanism of fruits remain unclear. In this review, we discuss the latest research on fruit shape. In addition, we compare the current theories on the molecular mechanisms that regulate fruit growth, size, and shape in different vegetable families.

Fruit size is a highly valued commercial trait in peach. Competition among fruit and among other sinks on a tree reduces potential growth rate of the fruit. Hence, crop-load management strategies such as thinning (removal of flowers or fruit) are often practiced by growers to optimize fruit size. Thinning can be performed at bloom or during early fruit development and at different intensities to optimize fruit growth responses. Responses to thinning may be cultivar and location specific. The objective of the current study was to fine-tune thinning strategies in the southeastern United States, a major peach producing region. Timing and intensity of thinning were evaluated across multiple cultivars over three years. Thinning at bloom or at 21 d after full bloom (DAFB) improved fruit size in comparison to unthinned trees in 'Cary Mac' and 'July Prince', respectively, in one year. Bloom-thinning reduced fruit yield (kg per tree) in the above cultivars in one year, suggesting that flower thinning alone may not be a viable option in this region. Intensity of thinning, evaluated as spacings of 15 cm and 20 cm between fruit, did not differentially affect fruit weight or yield. However, fruit diameter decreased quadratically with increasing fruit number per tree in 'Cary Mac', 'July Prince' and 'Summer Flame'. Similarly, fruit weight decreased quadratically in response to increase in fruit number per tree in 'Cary Mac' and 'July Prince'. Further, yield-per-tree decreased with increasing fruit size in 'Cary Mac' and 'July Prince'. Importantly, these relationships were cultivar specific. Together, the data suggest that achieving a target fruit number per tree is an effective strategy for crop-load management to optimize fruit size in southeastern peach production. The target fruit number per tree may potentially be achieved through a combination of flower and fruit-thinning during early fruit development. Such an approach may provide flexibility in crop-load management in relation to adverse weather events. [ABSTRACT FROM AUTHOR]

Background: Expansins (EXPs) facilitate non-enzymatic cell wall loosening during several phases of plant growth and development including fruit growth, internode expansion, pollen tube growth, leaf and root development, and during abiotic stress responses. In this study, the spatial and temporal expression patterns of C. annuum α- EXPANSIN (CaEXPA) genes were characterized. Additionally, fruit-specific CaEXPA expression was correlated with the rate of cell expansion during bell pepper fruit development. Results: Spatial expression patterns revealed that CaEXPA13 was up-regulated in vegetative tissues and flowers, with the most abundant expression in mature leaves. Expression of CaEXPA4 was associated with stems and roots. CaEXPA3 was expressed abundantly in flower at anthesis suggesting a role for CaEXPA3 in flower development. Temporal expression analysis revealed that 9 out of the 21 genes were highly expressed during fruit development. Of these, expression of six genes, CaEXPA5, CaEXPA7, CaEXPA12, CaEXPA14 CaEXPA17 and CaEXPA19 were abundant 7 to 21 days after anthesis (DAA), whereas CaEXPA6 was strongly expressed between 14 and 28 DAA. Further, this study revealed that fruit growth and cell expansion occur throughout bell pepper development until ripening, with highest rates of fruit growth and cell expansion occurring between 7 and 14 DAA. The expression of CaEXPA14 and CaEXPA19 positively correlated with the rate of cell expansion, suggesting their role in post-mitotic cell expansion-mediated growth of the bell pepper fruit. In this study, a ripening specific EXP transcript, CaEXPA9 was identified, suggesting its role in cell wall disassembly during ripening. Conclusions: This is the first genome-wide study of CaEXPA expression during fruit growth and development. Identification of fruit-specific EXPAs suggest their importance in facilitating cell expansion during growth and cell wall loosening during ripening in bell pepper. These EXPA genes could be important targets for future manipulation of fruit size and ripening characteristics. [ABSTRACT FROM AUTHOR]

Background: The major fleshy tissues of the apple fruit are spatially separable into cortex and pith. These tissues display differential growth during development. Key features of such differential growth, and sink metabolic programs supporting it have not been investigated previously. We hypothesized that differential growth between these fruit tissues is supported by differential sink metabolic programs, particularly during early development. Growth, metabolite concentrations, and transcript abundance of metabolism-related genes were measured to determine characteristics of differential growth and their underlying metabolic programs. Results: The cortex displayed > 5-fold higher growth than the pith during early fruit development, indicating that differential growth was established during this period. Further, when resource availability was increased through sink-removal, cortex growth was preferentially enhanced. Greatest diversity in metabolic programs between these tissues was evident during early fruit development. Higher cortex growth during early development was facilitated by increased catabolism of imported carbon (C) resources, sorbitol and sucrose, and the nitrogen (N) resource, asparagine. It was also associated with enhanced primary C metabolism, and C storage as malate and quinate. The pith metabolic program during this period involved limited allocation of C and N to growth, but greater allocation to storage, and enhanced sucrose-sucrose cycling. Conclusions: Together, these data indicate that the fruit cortex tissue displays a resource intensive metabolic program during early fruit development. This provides the C backbones, proteins, energy and osmolytes to support its higher growth. [ABSTRACT FROM AUTHOR]

Fruit size is a highly valued commercial trait in peach. Competition among fruit and among other sinks on a tree reduces potential growth rate of the fruit. Hence, crop-load management strategies such as thinning (removal of flowers or fruit) are often practiced by growers to optimize fruit size. Thinning can be performed at bloom or during early fruit development and at different intensities to optimize fruit growth responses. Responses to thinning may be cultivar and location specific. The objective of the current study was to fine-tune thinning strategies in the southeastern United States, a major peach producing region. Timing and intensity of thinning were evaluated across multiple cultivars over three years. Thinning at bloom or at 21 d after full bloom (DAFB) improved fruit size in comparison to unthinned trees in ‘Cary Mac’ and ‘July Prince’, respectively, in one year. Bloom-thinning reduced fruit yield (kg per tree) in the above cultivars in one year, suggesting that flower thinning alone may not be a viable option in this region. Intensity of thinning, evaluated as spacings of 15 cm and 20 cm between fruit, did not differentially affect fruit weight or yield. However, fruit diameter decreased quadratically with increasing fruit number per tree in ‘Cary Mac’, ‘July Prince’ and ‘Summer Flame’. Similarly, fruit weight decreased quadratically in response to increase in fruit number per tree in ‘Cary Mac’ and ‘July Prince’. Further, yield-per-tree decreased with increasing fruit size in ‘Cary Mac’ and ‘July Prince’. Importantly, these relationships were cultivar specific. Together, the data suggest that achieving a target fruit number per tree is an effective strategy for crop-load management to optimize fruit size in southeastern peach production. The target fruit number per tree may potentially be achieved through a combination of flower and fruit-thinning during early fruit development. Such an approach may provide flexibility in crop-load management in relation to adverse weather events.

An understanding of variation in fruit quality in relation to tree age can help understand the issue of poor fruit quality in young orchards; however, limited information is available on the citrus fruit. In this study, the endogenous nutritional status in rind, rag, and leaves; pectin status in rind and rag; and anatomical fruit growth parameter in rind tissues were studied in ‘Kinnow’ mandarins fruit during their development on trees from three age (6-, 18-, and 35-year-old) groups. In older (35-year-old) trees, rind, rag, and leaf nitrogen (N), phosphorus (P), and potassium (K) concentrations were superior. In fruit from all tree age groups, total pectin and protopectin reduced; however water-soluble pectin (WSP) improved. In rind tissues harvested from young (6-year-old) trees, cell density was more while cell size was less. In all tree age groups, cell density in rind tissues correlated negatively with rind WSP. [ABSTRACT FROM AUTHOR]

The temporal changes of nutrient concentration in leaves and their accumulation in fruit are good indicators of plant nutrient demand for each developmental stage. Seasonality of nutrients in leaves and fruits of pomegranate and their relation with fruit quality was evaluated in commercial orchards using cv. “Bhagwa.” The concentration of nitrogen (N), phosphorus (P), potassium (K), sulfur (S), iron (Fe), zinc (Zn) and boron (B) in leaves decreased while calcium (Ca), magnesium (Mg), manganese (Mn) and copper (Cu) concentration increased during fruit growth and development. Total nutrient accumulation increased gradually in fruit and translated into growth of arils, and increase in juice content and total soluble solids, however as the biomass accumulation in fruit was much faster than nutrient accumulation, concentration of majority nutrients except Mg decreased rapidly, followed by slow and continuous decrease till maturity. During fruit enlargement, demand for N, P, K, Fe, Cu and Zn was high while requirement for Ca, Mg and S was high during fruit development. [ABSTRACT FROM PUBLISHER]

In order to the seasonal growth patterns of pecan [Carya illinoensis (Wagenh.) K. Koch] fruit to provide references for cultivation and management of pecan orchards,four commercial varieties of pecan (‘Pawnee', ‘Western', ‘Shoshoni'and ‘Mahan') were evaluated over two growing seasons (2012- 2013) to build Logistic model on cross and longitudinal diameters, and the fruits dissected in longitudinal section were examined in morphological stages. The results showed that the seasonal growth of four pecan fruits performed ‘S' curves, and the coefficient of Logistic model was higher than 0. 9614, showing remarkable differences with actual growth data. Logistic model could provide more accurate forecast for pecan fruit seasonal growth and development, which the different developing stages (preliminary stage, rapid growth stage and final growth stage) of the fruits were determined, and their internal growths were controlled. [ABSTRACT FROM AUTHOR]

In drupe-type fruits, pit hardening, resulting from sclerification of the fruit endocarp, is widely used as a phenological marker for both physiological studies and orchard management. In spite of the importance of pit hardening for understanding fruit development processes and for agricultural practices, however, its quantification has remained obscure and precision has been lost with time and lax usage. In this study, we used a mechanical device to measure the physical pressure required to break the olive pit in order to define the timing of pit hardening more precisely and to permit closer observation of its relationship to fruit and endocarp growth and development. Over 4 years we found that pit-hardening pressure increased following a sigmoid pattern, at first gradually but then with a large and rapid increment of change in a relatively short period of time. The rapid acceleration of hardening began at the time when pit longitudinal and transverse diameters attained their maximum size. That timing is consistent with the anatomical differentiation of the sclerified endocarp cells which can no longer expand nor divide. The results improve our knowledge of pit hardening and provide a more precise context for evaluating the metabolic costs, physiological interactions and genetic controls of stone fruit endocarp development. On a practical level, the association of the intensification of pit-breaking pressure with the cessation of pit expansion indicates that pit diameters can be useful morphological markers to identify the onset of this period. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, two full length cDNAs of GH3 genes, named DlGH3.1 and DlGH3.2 were cloned from pericarp and aril tissues of the longan fruit, respectively. Three conserved motifs, SSGTSAGERK, YASSE and YRVGD, as a characteristic of the acyladenylate/thioester forming enzyme superfamily were observed in DlGH3.1 and DlGH3.2 proteins. DlGH3.1 mainly expressed in pericarp tissues while DlGH3.2 accumulated in both the pericarp and aril tissues during fruit growth and development. In addition, NAA treatment induced the expression of DlGH3.1 and DlGH3.2 in the pericarp tissues at 21 and 77days after anthesis (DAA), while only DlGH3.2 in the aril tissues could be induced by NAA at 77DAA. More importantly, ABA and ethrel treatments suppressed the accumulations of DlGH3.1 and DlGH3.2 in the pericarp tissues of longan fruit at 21DAA (a rapid growth stage of pericarp), but enhanced DlGH3.2 expression in the aril tissues at 77DAA (a fruit ripening stage). Furthermore, the expression patterns of DlGH3.1 and DlGH3.2 showed different tissue specificity. Thus, our results suggest that DlGH3.1 gene expression might be associated with pericarp growth, while DlGH3.2 accumulation is likely to be related to both pericarp growth and fruit ripening, and the responses of DlGH3s to plant growth hormones are different and dependent on fruit development stage and fruit tissue. [Copyright &y& Elsevier]

Abstract: Pomegranate fruit is an important source of potentially healthy bioactive compounds and mineral nutrients. Changes in total phenolic compound, concentrations, and levels of macronutrients (P, K, N, Mg, Ca and Na) and micronutrients (Zn, Cu, Mn, Fe and B) in arils and peel of pomegranate fruit were recorded from 10 days after full bloom until harvest. Total phenolics levels increased at early stage of growth both in peel and arils of fruit, but thereafter generally decreased during maturation and reached to 3.70 and 50.22mgg−1 of dry weight in arils and peel, respectively, at harvest. The amount of total phenolics in peel was markedly higher than arils of pomegranate fruit. The concentration of most elements in arils and peel decreased during fruit growth and development. At harvest the relative order of concentration of macronutrients both in arils and peel was K>N>Ca>P>Mg>Na. The concentration of most micronutrients was greater in the arils than in the peel especially in early season. The relative order of concentration of micronutrients in arils was B>Fe>Zn>Cu>Mn. The accumulation of all the macro- and microelement within the fruit also increased during fruit growth and development. These results provide important data on total phenolics and macro- and micronutrient changes during fruit growth and development, emphasizing that pomegranate fruit can be a good source of bioactive compounds and minerals. [Copyright &y& Elsevier]

During early pea fruit growth, the physiological roles of 4-chloroindole-3-acetic acid (4-Cl-IAA) and IAA, natural pea auxins, in regulating gibberellin (GA) 20-oxidase gene expression ( PsGA20ox1) were tested with 4-position, ring-substituted auxins that have a range of biological activities (fruit growth). The effect of seeds, and natural and synthetic auxins (4-Cl-IAA, and IAA; 4-Me-IAA, 4-Et-IAA and 4-F-IAA, respectively), and auxin concentration (4-Cl-IAA) on PsGA20ox1 mRNA levels in pea pericarp were investigated over a 24 h treatment period. The ability of the 4-substituted auxins to increase PsGA20ox1 mRNA levels in deseeded pericarp was correlated with their ability to stimulate pericarp growth. The greatest increase in pericarp PsGA20ox1 mRNA levels and growth was observed when deseeded pericarps were treated with the naturally occurring pea auxin, 4-Cl-IAA; however, IAA was not effective. Silver thiosulfate, an ethylene action antagonist, did not reverse IAA's lack of stimulation of PsGA20ox1 over the control treatment. 4-Me-IAA was the second most active auxin in stimulating PsGA20ox1 and was the second most biologically active auxin. Application of the 4-substituted IAA analogs, 4-Et-IAA and 4-F-IAA, to deseeded pericarps resulted in minimal or no increase in PsGA20ox1 transcript levels or pericarp growth. Pericarp PsGA20ox1 mRNA levels increased with increasing 4-Cl-IAA concentration and showed transitory increases at low 4-Cl-IAA treatments (30 to 300 pmol). These results support a unique physiological role for the auxin 4-Cl-IAA in the regulation of GA metabolism by effecting PsGA20ox1 expression during early pea fruit growth. [ABSTRACT FROM AUTHOR]

• Oil accumulation rate in olive is proportional to the increase in fruit dry weight. • This proportionality remains rather independent of crop load or water status. • A simple model predicts oil accumulation dynamics with minor input requirements. • The model can help in the definition of rational criteria for setting harvest date. Harvest timing in olive orchards has a strong effect on the quality and quantity of oil yield, but many farmers still lack simple and affordable quantitative tools for rationally deciding appropriate harvest dates. This study presents and tests a conceptual model for predicting fruit oil content (O f , g oil fruit−1) from inexpensive measurements of fruit dry weight (w f). The model presents two physiologically relevant parameters, the fruit dry weight at the onset of the oil accumulation phase (w f0) and the ratio of accumulated oil per unit of fruit dry weight increase during the oil accumulation period (β), the latter assumed invariable throughout ripening. A compilation of data on w f and O f dynamics collected from four experiments including six olive cultivars and contrasting conditions of water supply and crop load was used to test the model. Our results suggest that β could be fairly independent of crop load or watering regime and, probably, genetically controlled. By contrast, w f0 is clearly affected by both the cultivar and the availability of assimilates for fruit growth preceding oil accumulation, which makes it orchard- and year-specific. According to those premises, once cultivar-specific β values are available w f0 could be easily calibrated by either a single determination of O f and w f at any time during the oil accumulation phase (Approach A) or by directly measuring w f0 if the date for the onset of oil accumulation can be estimated (Approach B). Validation tests with an independently calibrated β showed an excellent performance for reproducing O f patterns from w f data using Approach A. Approach B satisfactory predicted oil accumulation rates, but absolute estimates of O f were less reliable. Regardless of the calibration approach, the model is easy to implement and has a minimal cost, which satisfies the demand for inexpensive tools for monitoring oil accumulation dynamics. [ABSTRACT FROM AUTHOR]