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Yaffa L Grossman - One of the best experts on this subject based on the ideXlab platform.
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maximum Fruit Growth potential following resource limitation during peach Growth
Annals of Botany, 1995Co-Authors: Yaffa L Grossman, Theodore M. DejongAbstract:Abstract To achieve its maximum organ Growth potential, an organ must grow at its potential relative Growth rate (RGR) throughout development. When resource availability limits Growth, the RGR is reduced below the potential RGR. This study examines whether, following a period of resource-limited Growth, the RGR is able to increase to the potential RGR when sufficient resources are available. Fruit RGRs of a late maturing peach cultivar were examined following removal of most of the Fruits (heavy thinning) from previously unthinned trees in Apr., May, and Jun. The Fruit RGRs after imposition of the thinning treatments were higher than those on unthinned trees during source-limited periods of the growing season, suggesting that Fruit RGR can increase in response to increased resource availability. In general, the RGRs of Fruits of trees thinned in Apr., May, and Jun. did not exceed those of Fruits on trees thinned at bloom, suggesting that heavy thinning at bloom provides a reasonable estimate of the potential RGR. There were times, however, when the effects of competition with vegetative sinks were apparent, suggesting that the RGR of Fruits on trees that were heavily thinned at bloom may underestimate the potential RGR during these times. The absolute Growth rates of Fruits on thinned trees were greater than those on unthinned trees, but generally were not greater than those on trees that were thinned at bloom, suggesting that peach Fruits are unable to recover potential Growth lost during resource-limited Growth periods.
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maximum Fruit Growth potential and seasonal patterns of resource dynamics during peach Growth
Annals of Botany, 1995Co-Authors: Yaffa L Grossman, Theodore M. DejongAbstract:Maximum Fruit Growth potential, the Growth attained by Fruits when they are grown under optimal environmental conditions in the presence of a non-limiting supply of resources, was estimated for two peach [Prunus persica (L.) Batsch] cultivars that differ in the timing of resource demand for reproductive Growth. Maximum potential Fruit Growth was estimated on trees that were heavily thinned at bloom. On these trees, resource availability exceeded resource demand for Fruit Growth. For both cultivars, the mean dry weights of Fruits grown on unthinned trees were approximately half the mean dry weights of Fruits grown on trees that were heavily thinned at bloom, indicating that Fruit Growth was source-limited on unthinned trees. Comparison of the seasonal patterns of relative Growth rate of Fruits on unthinned and heavily thinned trees indicated the source-limited Fruit Growth occurred during distinct periods of the growing season. On the early maturing cultivar, source-limited Fruit Growth occurred from 300 degree-days after bloom until harvest (4·5-10 weeks after bloom). On the late maturing cultivar, source-limited Fruit Growth occurred from 200-900 and 1600-1900 degree-days (3·5-12 and 18-20 weeks) after bloom. Although the final dry weight of Fruits on the early maturing cultivar was only half that of Fruits on the late maturing cultivar, the potential net sink strength of Fruits was significantly higher on the early than the late maturing cultivar throughout the entire Growth period of the early maturing cultivar. Resource availability for Fruit Growth was similar on the early and late maturing cultivars, indicating that selection for early maturing Fruits has not changed the patterns of resource availability for Fruit Growth.
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quantifying sink and source limitations on dry matter partitioning to Fruit Growth in peach trees
Physiologia Plantarum, 1995Co-Authors: T M Dejong, Yaffa L GrossmanAbstract:We describe an approach for determining the degree of sink and source limitations on peach (Prunus persica L. Batsch) Fruit Growth during several Growth periods. Source limitations on Fruit Growth may be due to either a shortfall in assimilate supply within the tree (supply limitation) or to a deficiency in the capacity of the translocation system to deliver assimilates in sufficient quantity to support the maximum Fruit Growth rate (transport/competition limitation). To ascertain the potential maximum rate of Fruit Growth, Fruit thinning treatments were used. One month after bloom, the number of Fruits per tree was adjusted to between 50 and 700 on an early and a late maturing peach cultivar (cvs Spring Lady and Cal Red, respectively). Rates of potential sink demand, potential source supply and actual Fruit Growth were estimated from sequential harvests of all Fruits on 42 trees on two (Spring Lady) and three (Cal Red) dates. These values were used to estimate the proportion of potential Growth achieved, and the supply and transport/competition limitations on Fruit Growth. The results indicated that source limitations were significant on trees with moderate to high Fruit numbers. These source limitations were due to supply limitations during all harvest intervals and to transport/competition limitations during the early harvest intervals. Sink limitations occurred to the greatest extent during the mid-period of Fruit Growth on the later maturing cultivar.
Theodore M. Dejong - One of the best experts on this subject based on the ideXlab platform.
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maximum Fruit Growth potential following resource limitation during peach Growth
Annals of Botany, 1995Co-Authors: Yaffa L Grossman, Theodore M. DejongAbstract:Abstract To achieve its maximum organ Growth potential, an organ must grow at its potential relative Growth rate (RGR) throughout development. When resource availability limits Growth, the RGR is reduced below the potential RGR. This study examines whether, following a period of resource-limited Growth, the RGR is able to increase to the potential RGR when sufficient resources are available. Fruit RGRs of a late maturing peach cultivar were examined following removal of most of the Fruits (heavy thinning) from previously unthinned trees in Apr., May, and Jun. The Fruit RGRs after imposition of the thinning treatments were higher than those on unthinned trees during source-limited periods of the growing season, suggesting that Fruit RGR can increase in response to increased resource availability. In general, the RGRs of Fruits of trees thinned in Apr., May, and Jun. did not exceed those of Fruits on trees thinned at bloom, suggesting that heavy thinning at bloom provides a reasonable estimate of the potential RGR. There were times, however, when the effects of competition with vegetative sinks were apparent, suggesting that the RGR of Fruits on trees that were heavily thinned at bloom may underestimate the potential RGR during these times. The absolute Growth rates of Fruits on thinned trees were greater than those on unthinned trees, but generally were not greater than those on trees that were thinned at bloom, suggesting that peach Fruits are unable to recover potential Growth lost during resource-limited Growth periods.
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maximum Fruit Growth potential and seasonal patterns of resource dynamics during peach Growth
Annals of Botany, 1995Co-Authors: Yaffa L Grossman, Theodore M. DejongAbstract:Maximum Fruit Growth potential, the Growth attained by Fruits when they are grown under optimal environmental conditions in the presence of a non-limiting supply of resources, was estimated for two peach [Prunus persica (L.) Batsch] cultivars that differ in the timing of resource demand for reproductive Growth. Maximum potential Fruit Growth was estimated on trees that were heavily thinned at bloom. On these trees, resource availability exceeded resource demand for Fruit Growth. For both cultivars, the mean dry weights of Fruits grown on unthinned trees were approximately half the mean dry weights of Fruits grown on trees that were heavily thinned at bloom, indicating that Fruit Growth was source-limited on unthinned trees. Comparison of the seasonal patterns of relative Growth rate of Fruits on unthinned and heavily thinned trees indicated the source-limited Fruit Growth occurred during distinct periods of the growing season. On the early maturing cultivar, source-limited Fruit Growth occurred from 300 degree-days after bloom until harvest (4·5-10 weeks after bloom). On the late maturing cultivar, source-limited Fruit Growth occurred from 200-900 and 1600-1900 degree-days (3·5-12 and 18-20 weeks) after bloom. Although the final dry weight of Fruits on the early maturing cultivar was only half that of Fruits on the late maturing cultivar, the potential net sink strength of Fruits was significantly higher on the early than the late maturing cultivar throughout the entire Growth period of the early maturing cultivar. Resource availability for Fruit Growth was similar on the early and late maturing cultivars, indicating that selection for early maturing Fruits has not changed the patterns of resource availability for Fruit Growth.
Benoît Pallas - One of the best experts on this subject based on the ideXlab platform.
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impact of within tree organ distances on floral induction and Fruit Growth in apple tree implication of carbon and gibberellin organ contents
bioRxiv, 2019Co-Authors: Fares Belhassine, Sylvie Bluy, Damien Fumey, Jean-jacques Kelner, Sebastien Martinez, Evelyne Costes, Benoît PallasAbstract:Abstract In plants, organs are inter-dependent for Growth and development. Here, we aimed to investigate the distance at which interaction between organs operates and the relative contribution of within-tree variation in carbohydrate and hormonal contents on floral induction and Fruit Growth, in a Fruit tree case study. Manipulations of leaf and Fruit numbers were performed in two years on ‘Golden delicious’ apple trees, at the shoot or branch scale or one side of Y-shape trees. For each treatment, floral induction proportion and mean Fruit weight were recorded. Gibberellins content in shoot apical meristems, photosynthesis, and non-structural carbohydrate concentrations in organs were measured. Floral induction was promoted by leaf presence and Fruit absence but was not associated with non-structural content in meristems. This suggests a combined action of promoting and inhibiting signals originating from leaves and Fruit, and involving gibberellins. Nevertheless, these signals act at short distance only since leaf or Fruit presence at long distances had no effect on floral induction. Conversely, Fruit Growth was affected by leaf presence even at long distances when sink demands were imbalanced within the tree, suggesting long distance transport of carbohydrates. We thus clarified the inter-dependence and distance effect among organs, therefore their degree of autonomy that appeared dependent on the process considered, floral induction or Fruit Growth.
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impact of within tree organ distances on floral induction and Fruit Growth in apple tree implication of carbohydrate and gibberellin organ contents
Frontiers in Plant Science, 2019Co-Authors: Fares Belhassine, Sylvie Bluy, Damien Fumey, Jean-jacques Kelner, Sebastien Martinez, Evelyne Costes, Benoît PallasAbstract:In plants, organs are inter-dependent for Growth and development. Here, we aimed to investigate the distance at which interaction between organs operates and the relative contribution of within-tree variation in carbohydrate and hormonal contents on floral induction and Fruit Growth, in a Fruit tree case study. Manipulations of leaf and Fruit numbers were performed in two years on ‘Golden delicious’ apple trees, at the shoot or branch scale or one side of Y-shape trees. For each treatment, floral induction proportion and mean Fruit weight were recorded. Gibberellins content in shoot apical meristems, photosynthesis, and non-structural carbohydrate concentrations in organs were measured. Floral induction was promoted by leaf presence and Fruit absence but was not associated with non-structural content in meristems. This suggests a combined action of promoting and inhibiting signals originating from leaves and Fruit, and involving gibberellins. Nevertheless, these signals act at short distance only since leaf or Fruit presence at long distances had no effect on floral induction. Conversely, Fruit Growth was affected by leaf presence even at long distances when sink demands were imbalanced within the tree, suggesting long distance transport of carbohydrates. We thus clarified the inter-dependence and distance effect among organs, therefore their degree of autonomy that appeared dependent on the process considered, floral induction or Fruit Growth.
Rafael Domingo - One of the best experts on this subject based on the ideXlab platform.
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effects of timing and intensity of deficit irrigation on vegetative and Fruit Growth of apricot trees
Agricultural Water Management, 2014Co-Authors: A Perezpastor, M C Ruizsanchez, Rafael DomingoAbstract:The effect of different deficit irrigation strategies were studied over a four year period in mature apricot trees (Prunus armeniaca L., cv. Bulida) to ascertain how the intensity and duration of water deficit affects the Growth of the root and aerial (shoot, trunk and Fruit) parts of the tree, and hence future tree productivity. The irrigation treatments consisted of: a control, irrigated at 100% of seasonal crop evapotranspiration (ETc); continuous deficit irrigation (CDI) at 50% of ETc; two regulated deficit irrigation (RDI), at 100% of ETc only during the critical periods, and reduced to various percentages of ETc during the rest of the season. Soil and plant water status, yield, vegetative and Fruit Growth were measured in the different treatments. Vegetative Growth decreased according to the intensity and duration of the water deficit applied, and depending on the phenological period when the water deficit occurred. Deficit irrigation promoted a decrease in trunk and shoot Growth by a 33% on average, although root length density increased nearly double in the 0–0.25m drip-line band compared with the Control trees. In the RDI treatments, trunk Growth and pruning were significantly reduced only under severe water deficit conditions. While CDI proved to be detrimental for maintaining Fruit yield due to the significant reduction in vegetative Growth, which led to a decrease in the number of Fruits per tree, the RDI treatments only led to reduced yields when the water deficits during the non-critical periods were severe, tree trunk Growth being significantly reduced as a consequence. Also, Fruit size and total yield decreased when deficit irrigation relief was delayed until after the onset of stage III. Overall, water saving up to 22% affected negatively to the total yield and the number of Fruits per tree, by reducing the tree Growth.
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the effects of contrasted deficit irrigation strategies on the Fruit Growth and kernel quality of mature almond trees
Agricultural Water Management, 2009Co-Authors: Gregorio Egea, Maria M Gonzalezreal, A Baille, Pedro A Nortes, Paloma Sanchezbel, Rafael DomingoAbstract:The aim of this study was to quantify and compare the effects of two different deficit irrigation (DI) strategies (regulated deficit irrigation, or RDI, and partial rootzone drying, PRD) on almond (Prunus dulcis (Mill.) D.A. Webb) Fruit Growth and quality. Five irrigation treatments, ranging from moderate to severe water restriction, were applied: (i) full irrigation (FI), irrigated to satisfy the maximum crop water requirements (ETc); (ii) regulated deficit irrigation (RDI), receiving 50% of ETc during the kernel-filling stage and at 100% ETc throughout the remaining periods; and three PRD treatments - PRD70, PRD50 and PRD30 - irrigated at 70%, 50% and 30% ETc, respectively, during the whole Growth season. The DI treatments did not affect the overall Fruit Growth pattern compared to the FI treatment, but they had a negative impact on the final kernel dry weight for the most stressed treatments. The allocation of water to the different components of the Fruit, characterized by the fresh weight ratio of kernel to Fruit, appeared to be the process most clearly affected by DI. Attributes of the kernel chemical composition (lipid, protein, sugar and organic acid contents) were not negatively affected by the intensity of water deprivation. Overall, our results indicated that PRD did not present a clear advantage (or disadvantage) over RDI with regard to almond Fruit Growth and quality.
Caixi Zhang - One of the best experts on this subject based on the ideXlab platform.
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partitioning of 13c photosynthates from different current shoots neighboring with Fruiting spur in later maturing japanese pear during the period of rapid Fruit Growth
Scientia Horticulturae, 2008Co-Authors: Caixi Zhang, Kenji TanabeAbstract:Abstract To elucidate the fate of photosynthates from different current shoots and their influence on Fruit Growth and bud differentiation in neighboring spur complex during the period of rapid Fruit Growth in two late-maturing Japanese pear cultivars: ‘Atago’ and ‘Shinkou’ with contrasting Fruit size, 13 C labeling of single shoot was done to investigate of C-relations in Fruit branches of eight shoot-combinations. The results showed that all of the current shoots investigated (bourse shoots of nonFruiting spur, bourse shoots of Fruiting spur, extension shoot, nonFruiting spur, vegetative shoot, and water sprout) could export photosynthates to the neighboring Fruit and buds. Water sprouts together with vegetative shoots, bourse shoots, and extension shoots are important source for Fruit Growth after shoot Growth termination during the period of rapid Fruit Growth in production of late-maturing pears. The carbon transfer rate from the neighboring to the Fruit bearing spur is depent (i) on the types of shoot which acts as C source, (ii) on the position of the Fruiting spur and (iii) on the source-sink distance. Furthermore, the cultivar difference in carbon partitioning from different current shoot-combinations confirmed that the movement of photosynthates into the Fruit was determined by sink strength of the Fruit, and ‘Atago’ exhibited a greater relative sink strength of Fruit than ‘Shinkou’. In addition, vegetative shoots are very important C sources for Fruit Growth in ‘Atago’ and the Growth pattern of bourse shoot seriously affects C allocated to Fruit in ‘Shinkou’.
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13c photosynthate accumulation in japanese pear Fruit during the period of rapid Fruit Growth is limited by the sink strength of Fruit rather than by the transport capacity of the pedicel
Journal of Experimental Botany, 2005Co-Authors: Caixi Zhang, Fumio Tamura, Kazuhiro Matsumoto, Kenji Tanabe, Akira YoshidaAbstract:In Japanese pear, the application of GA 3+4 during the period of rapid Fruit Growth resulted in a marked increase in pedicel diameter and bigger Fruit at harvest. To elucidate the relationship between pedicel capacity and Fruit Growth and to determine the main factor responsible for larger Fruit size at harvest, Fruit Growth and pedicel vascularization after GA application were examined and the carbohydrate fluxes were monitored in a spur unit by non-invasive techniques using 13 C tracer. Histological studies of Fruit revealed that GA increased the cell size of the mesocarp but not the cell number and core size. The investigation of carbon partitioning showed that an increase in the specific rate of carbohydrate accumulation in Fruit or the strength of Fruit should be responsible for an increase of Fruit weight in GA-treated trees. Observation of pedicel vascularization showed that an increase in pedicel cross-sectional area (CSA) by GA application mainly resulted from phloem and xylem CSA, but it is unlikely that an increase in the transport system is the direct factor for larger Fruit size. Therefore, it can be concluded that larger Fruit size resulting from GA application during the period of rapid Fruit Growth caused an increase in the cell size of the mesocarp and increased carbon partitioning to the Fruit. Although GA is closely involved with pedicel vascularization, it seems that photosynthate accumulation in Fruit is limited by the sink strength of Fruit rather than by the transport capacity of the pedicel.
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spur characteristics Fruit Growth and carbon partitioning in two late maturing japanese pear pyrus pyrifolia nakai cultivars with contrasting Fruit size
Journal of the American Society for Horticultural Science, 2005Co-Authors: Caixi Zhang, Fumio Tamura, Kenji Tanabe, Akihiro Itai, Shiping WangAbstract:13 CO2, photosynthesis, sink strength, Fruit development ABSTRACT. The aim of this study was to investigate the roles of spur characteristics and carbon partitioning in regulating cultivar differences in Fruit size of two late-maturing japanese pear cultivars, ʻAtagoʼ and ʻShinkouʼ. The study of spur characteristics showed that the two cultivars displayed different patterns in leaf development, fl ower characteristics, Fruit Growth, and shoot type. In contrast to ʻAtagoʼ with dramatically larger Fruit, ʻShinkouʼ is a heavily spurred cultivar with a higher total leaf area and leaf number per spur early in Fruit Growth, less vegetative shoots, and smaller Fruit but larger core. No signifi cant differences were obtained in specifi c leaf weight, leaf thickness, chlorophyll content, and net photosynthesis of mature leaves, and seed number per Fruit between the two cultivars. The results of trace experiment with 13 C revealed that on a spur basis, there were no signifi cant differences in the amount of 13 C assimilate produced by spur leaves on each labeling date except at 190 days after anthesis, however, there were highly signifi cant differences in the amount of 13 C allocated to Fruit between cultivars. Moreover, a higher amount of 13 C assimilates was allocated to ʻAtagoʼ fl esh (or Fruit) than that in ʻShinkouʼ. Analysis of relative sink strength (RSS) indicates that the sink strength of Fruit was dominant over those of other organs in the spur measured in both cultivars except at the early stage of Fruit Growth. ʻAtagoʼ exhibited a greater RSS of Fruit and lower losses of 13 C for respiration and export than
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partitioning of 13 c photosynthate from spur leaves during Fruit Growth of three japanese pear pyrus pyrifolia cultivars differing in maturation date
Annals of Botany, 2005Co-Authors: Caixi Zhang, Fumio Tamura, Kenji Tanabe, Akihiro Itai, Shiping WangAbstract:� Background and Aims In Fruit crops, Fruit size at harvest is an important aspect of quality. With Japanese pears (Pyrus pyrifolia), later maturing cultivars usually have larger Fruits than earlier maturing cultivars. It is considered that the supply of photosynthate during Fruit development is a critical determinant of size. To assess the interaction of assimilate supply and early/late maturity of cultivars and its effect on final Fruit size, the pattern of carbon assimilate partitioning from spur leaves (source) to Fruit and other organs (sinks) during Fruit Growth was investigated using three genotypes differing in maturation date. � Methods Partitioning of photosynthate from spur leaves during Fruit Growth was investigated by exposure of spurs to 13 CO2 and measurement of the change in 13 C abundance in dry matter with time. Leaf number and leaf area per spur, fresh Fruit weight, cell number and cell size of the mesocarp were measured and used to model the development of the spur leaf and Fruit. � Key ResultsCompared with the earlier-maturing cultivars ‘Shinsui’ and ‘Kousui’, the larger-Fruited, later-maturing cultivar ‘Shinsetsu’ had a greater total leaf area per spur, greater source strength (source weight · source specific activity), with more 13 C assimilated per spur and allocated to Fruit, smaller loss of 13 C in respiration and export over the season, and longer duration of cell division and enlargement. Histology shows that cultivar differences in final Fruit size were mainly attributable to the number of cells in the mesocarp. � Conclusions Assimilate availability during the period of cell division was crucial for early Fruit Growth and closely correlated with final Fruit size. Early Fruit Growth of the earlier-maturing cultivars, but not the later-maturing ones, was severely restrained by assimilate supply rather than by sink limitation. a 2005 Annals of Botany Company
