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1.
Fruit weight is strongly correlated to ovary weight in olive as big-fruited cultivars have larger ovaries and flowers at bloom. We tested the hypothesis that larger ovaries imply stronger sinks and therefore reduce fruit set, expressed as number of fruits. Flower/fruit load per centimeter of shoot was assessed every month from flowering to harvest, on sample shoots of many different olive cultivars differing in fruit size. Data were taken for two years: 2007 and 2008. Additionally, in 2008, a fruit thinning experiment was carried out by leaving a single fruit per shoot, to assess the maximum potential fruit weight achievable by each cultivar. Results indicated that fruit size was mostly genetically determined as thinned fruits of small-fruited cultivars, although bigger than control fruits, never got as big as fruits from large-fruited cultivars, confirming that large ovaries are a prerequisite for large fruits. Among all cultivars, the number of flowers per inflorescence, the number of inflorescences, and the number of flowers per centimeter of shoot were not correlated to average flower weight while total flower mass per centimeter of shoot was positively correlated to average flower weight (i.e. large flowered/fruited cultivars had greater total flower mass). However, one month after bloom and thereafter, all parameters were negatively and exponentially correlated with fruit average weight across cultivars, except fruit mass per centimeter of shoot which was generally not correlated to fruit average weight, except in one year, at harvest, when fruit mass per centimeter of shoot was positively correlated to fruit average weight. These results suggest that fruit set is a consequence of, and inversely proportional to flower/fruit size in olive.  相似文献   

2.
Sweet pepper (Capsicum annuum L.) cvs E-84066 and Yolo Wonder were grown under ambient conditions in plastic covered greenhouses. Anthesis commenced five and six weeks after planting and rose to a peak of 39 (E-84066) and 19 (Yolo Wonder) flowers per week respectively after which there was a rapid fall. Temperatures throughout anthesis were high (>38°C (maximum) and >16°C (minimum)) and this is likely to have contributed to the magnitude of the flux. Fruit set was highest in the early stages of the crop, but subsequently declined as the majority of flowers aborted. Overall, fruit weight was correlated with seed weight and seed number, and declined throughout the life of the crop. By contrast, seed size and the percentage germination remained constant. The latter is of particular importance for seed crops where seed quality is of primary concern.  相似文献   

3.
Summary

The phenology of wild stands of strawberry guava (Psidium cattleianum Sabine) was studied at 100, 480 and 720.m over 2 years in ReÂunion Island. The shoots bore flower buds at the basal nodes, and vegetative buds at the apical nodes. Trees produced vegetative growth from September to December, flowers from November to January and fruit from February to June. Shoot growth was earlier at 100 and 720.m the first year, but were synchronized in the second year. Flowering and fruiting were also earlier at 100.m. The intervals between shoot emergence and flowering, and flowering and fruit maturity were strongly related to temperature, with base temperatures of 5.58C and 2.68C, and heat units requirements of 675 and 2,5528C.d, respectively. The number of shoots, flowers and fruit per branch varied across sites and years, unrelated to temperature. However, production was significantly higher at 720.m. Production was much lower after a hurricane. Flowering (y) was related to shoot production per branch (x) (log(y)=111.33.log(x); r2.=.0.78), whereas the fruit set rate was highly variable between trees (26±100%). The number of fruits per branch (1±6) was possibly related to poor shoot growth or fruit set, but unrelated to the timing of the phenological events. It is expected that commercial orchards would be more productive than feral stands.  相似文献   

4.
Summary

The effects of whole-crown application of thidiazuron (TDZ), applied two weeks after full bloom, at the concentrations of 0 (control), 2 or 10 ppm, on vine yield, fruit quality and on next-season potential yield of Actinidia deliciosa ‘Hayward’ were evaluated in 1998–99. Fruit growth increased rapidly after TDZ application. Fruit fresh weight and yield increased by about 13% and 22% with the 2 and 10 ppm concentration, respectively. These responses were associated with only small changes in fruit shape, with 10 ppm-treated fruits slightly rounder than the control. During ripening, TDZ did not affect fruit soluble solid content, flesh firmness or concentration of non-structural carbohydrates. No effect was observed on the amount of winter pruning, entity of bud burst, percent of fertile buds, number of inflorescences per fertile bud or percent of vegetative buds. These results show that TDZ can be applied to the whole crown to increase fruit size and yield, without affecting fruit quality or the next-season’s crop.  相似文献   

5.
Summary

Fruit set and yield of the following cultivars of black currant (Ribes nigrum L.): `Ben Alder', `Ben Lomond', `Ben Nevis', `Ben Tirran', `Ceres', `Ojebyn', `Titania' and `Triton' were investigated in 1994±1996. Percentage fruit set, size of berries and yield of all investigated cultivars were higher when much foraging activity of pollinating insects was observed. The bushes on open-pollinated plots set more fruit (50-200%), had bigger fruits (10±20%) and gave higher yields (60±300%) than plants isolated from insects. All eight cultivars, including `Titania', had lower fruit set when pollinated with their own pollen under nets than when subjected to free pollination in open plots.  相似文献   

6.
Summary

Different concentrations of aminoethoxyvinylglycine (AVG) and gibberellic acid (GA3) and their combinations, applied at two stages of fruit growth, were evaluated for prolonging the marketing season of `Feicheng' peaches. GA3 applied at the end of pit hardening, or AVG applied two weeks before commercial harvest, inhibited fruit maturation on the tree, delayed harvest and reduced flesh browning after cold storage in a concentration-dependent manner. A synergistic effect was found when both GA3 and AVG were used, with the combination of 100 or 150.mg l±1 GA3, applied at the end of pit hardening, and 100 mg l±1 AVG, applied two weeks before harvest giving the best results. These combinations retarded the change in ground colour, loss of firmness, and reduction in acidity by 2±3 weeks. Since harvest was prolonged by 2±3 weeks, soluble solids content (SSC) in fruit increased compared with the control (harvested earlier). Fruit size was significantly greater on treated trees compared with the controls when fruit set was controlled to the same level by hand thinning. After four weeks of storage and 4.d at 208C, 83% of control fruit developed tissue browning, but only 5% of AVG + GA3-treated fruit developed browning after six weeks of storage and 4 d at 208C. Thus, the marketing season of `Feicheng' peaches was prolonged by at least four weeks by 100 or 150 mg l±1 of GA3 and 100 mg l±1 of AVG. Fruit treated with 150 mg l±1 GA3 plus 100 to 150 mg l±1 AVG showed similar results but failed to ripen properly after cold storage.  相似文献   

7.
Summary

The influence of wood age, fruiting position and leaf area within the tree canopy on fruit mineral content and quality for several apple (Malus domestica Borkh.) cultivars was investigated. Size and Ca, Mg and K content of individual fruit on one-year (lateral and terminal positions), two-year and older than three-year wood were compared for cvs Royal Gala, Braeburn, Granny Smith and Fuji. Fruit on two-year spurs and one-year terminals was generally larger at commercial harvest than that on one-year laterals and spurs older than three years. Flower receptacles at full bloom were larger and fruit growth rates were greater from 60 to 100 d after full bloom on two-year spurs than on one-year laterals. Fruit Ca and Mg concentrations and contents at commercial harvest were highest for terminal fruit, but there was no consistent difference between fruit from other positions. One-year terminals had the greatest primary and bourse leaf areas, two-year spurs were intermediate and one-year laterals had the lowest areas of both leaf types. Removal of 50% of primary leaves and/or removal of bourse shoots from clusters at bloom reduced fruit Ca content at commercial harvest for two-year spurs, one-year laterals and one-year terminals. Bourse shoot removal also reduced Mg content for all positions. However there was no effect of leaf removal on fruit size or K content. Ca content of individual fruit increased curvilinearly with increasing total spur leaf area for fruit on two-year spurs and one-year terminals but not for fruit on one-year lateral clusters. Terminal fruit with total spur leaf areas and fruit size similar to those on two-year spur fruit had higher Ca content.  相似文献   

8.
SUMMARY

The effects of temperature on the progamic phase, fertilization and initial fruit set in cross pollinated olives were studied to determine the reasons for poor fruit set when high temperatures occur during the bloom period. Fruit set in ‘Manzanillo’ olive was completely inhibited at 30°C constant temperature. This temperature significantly reduced pollen germination but did not prevent pollen tube growth. Ovule penetration by the pollen tube was observed in 47% of the flowers at 30°C; however, the lack of growth of both functional ovules and ovaries suggests problems in zygote formation or endosperm development. The most favourable temperature was 25°C, in which faster pollen tube growth, more and earlier fertilization, and more fruit set occurred. At 20°C pollen tube growth was slower, resulting in delayed and reduced fertilization.  相似文献   

9.
Summary

Levels of abortion of reproductive organs (i.e., buds, flowers, and young fruits) in sweet pepper plants (Capsicum annuum L.) are high, and cyclical fluctuations occur in fruit set. Stages susceptible to abortion are very young buds (< 2.5 mm), buds close to anthesis, and flowers and fruits up to 14 d after anthesis. An overview of factors and processes involved in flower and fruit abortion in sweet peppers is presented. More light, higher CO2 concentrations, and lower planting density, increase the availability of assimilates per plant, and decrease fruit abortion. The cyclical pattern in fruit set is caused by changes in demand for assimilates. High flower abortion occurs when fast growing fruit (at approx. 3 weeks after anthesis) are present, due to competition for assimilates. Fruit set increases when fast growing fruit are almost mature and have a low assimilate demand. Prior to abortion, auxin export from the reproductive organ diminishes, ethylene production increases, and lower levels of activity of sucrose-cleaving enzymes are found. Severe water stress and low nutrient supply also increase abortion levels. Low night- and high day-time temperatures hamper pollen development, causing low seed set, which can result in fruit abortion. Two theories have been used to explain abortion: unbalanced demand for and supply of assimilates, and hormonal dominance of developing fruit over young fruit. Attempts to prevent abortion or to diminish the cyclical pattern of fruit set have not yet been successful, but new suggestions are presented.  相似文献   

10.
Summary

Changes in water and dry-matter content of developing mango fruit (Mangifera indica L. ‘Lirfa’) were investigated over a single season in Réunion Island, along with the effects of leaf:fruit ratio (10, 25, 50, 100 and 150 leaves per fruit on girdled branches). As the fruit developed, about 8–13% of fruit water weight was in the peel compared with 78–86% in the pulp and 6–9% in the stone. When the data were expressed on a dry-weight basis, 12–20% was in the peel, 60–70% was in the pulp and 18–20% in the stone. At harvest, larger fruit, on treatment 100, had a higher proportion of weight in the pulp. Good relationships between water and dry weight of each fruit component were found, regardless of the treatment. They showed that the rate of water accumulation decreased when the dry weight increased and that the dry-matter content increased as the fruit developed as well. Increasing leaf:fruit ratio to 100 leaves per fruit improved fruit yield by 300 g and pulp dry-matter content by 6%, for a total of 550 g and 20% at harvest. Fruit quality as estimated by pulp dry-matter content could be calculated easily during the changes in fruit weight over the season. Moreover, this indicator could be useful to assess the maturity of mango fruit.  相似文献   

11.
Summary

`Huangjin' peaches (Prunus persica Batsch) were harvested at commercial harvest time (commercial) and 20 d before (early) or after (later) commercial harvest. Fruit from each harvest were stored at three temperature regimes (0, 5 and 10°C) at 95% r.h. After four weeks of storage at 0 or 5°C, early harvested fruit developed more leatheriness but less mealiness and later harvested fruit did not develop leatheriness but developed more mealiness comparedwith fruit from commercial harvest. Overall, fruit stored at 5°C developed more mealiness but less leatheriness than fruitat 0°C for the same period of storage. When stored at 10°C for two weeks, after which fruit were senescent, fruit did not develop any leatheriness or mealiness regardless of harvest times. Fruit with leatheriness were firmer (>30 N) thanjuicy or mealy fruit (<10 N) after the same period of cold storage and 4 d at 20°C. Mealy fruit were as soft as juicy fruit. 1-Aminocyclopropane-1-carboxylate oxidase (ACO) activity, 1-aminocyclopropane-1-carboxylic acid (ACC) content, and polygalacturonase (PG) and galactosidase (GAL) activities were lower, and insoluble pectin content was higher in leathery fruit than that in juicy or mealy fruit. ACO, PG and GAL activity, ACC, and insoluble pectin content were similar between mealy and juicy fruit.  相似文献   

12.
Summary

The combined effects of electrical conductivity (an EC of 2.5 dS m–1 or 8 dS m–1 in the root zone) and fruit pruning (three or six fruit per truss) on tomato fruit quality were studied in a greenhouse experiment, planted in January 2005. Taste-related attributes [dry matter content (DM), total soluble solids content (SSC), titratable acidity (TA), glucose, fructose and citric acid content] and health-promoting attributes (lycopene, βcarotene, vitamin C, and total anti-oxidant activity) of tomato fruits harvested on the vine from the fifth or tenth truss positions were determined. The quality of tomato fruits was improved by high EC. A high EC in the root zone increased the DM content, total SSC, TA, as well as glucose, fructose and citric acid contents. A significantly higher lycopene and βcarotene content was also observed [on a fresh weight (FW) and dry weight (DW) basis] with a high EC in the root zone. The accumulation of different compounds that determine tomato fruit quality differed between the fifth and tenth truss. In particular, the lycopene content was reduced, whereas the βcarotene content was increased in the tenth truss with respect to the fifth truss, most likely because of higher temperatures during ripening of the tenth truss. Fruit pruning increased fruit FW by 42% and positively influenced the DM content and total anti-oxidant activity, while a negative effect was observed on lycopene and citric acid contents (on a FW and DW basis). EC and fruit pruning both had a strong effect on fruit size; however, EC had a much stronger impact on taste and health-related fruit quality attributes. A small interaction between EC and fruit pruning was found for marketable yield, fructose and glucose content, fruit firmness, and P and Ca concentrations in fruits.  相似文献   

13.
Summary

Fruit mineral concentrations measured at harvest can have major effects on apple fruit quality on the tree or during storage. Orchard practices must therefore seek to optimize fruit mineral composition. The purpose of this study was to describe and elucidate the effects of hand thinning on whole trees and individual spurs on apple fruit mineral composition. Two methods of flower and fruitlet thinning were compared with no thinning on `Braeburn' and `Fiesta' apple trees. Alternate whole flower/fruitlet clusters or all but one flower/fruitlet within every cluster were removed at full bloom or 14±21 d after full bloom. Alternate-cluster thinning reduced final fruit numbers per tree and fruit Ca concentrations by up to 22%, while increasing final fruit size by up to 21%, compared with no thinning. These effects on fruit Ca concentrations were also measured across a range of fruit size classes. Within-cluster thinning at full bloom or up to 21 d after full bloom also reduced fruit numbers per tree but increased fruit size substantially, by up to 65% compared with no thinning, this effect being less for later thinning. However, fruit mineral concentrations were not influenced by this treatment. Some fruiting spurs were singled to one fruit 14 d after full bloom on alternately flower cluster thinned trees and on trees that had not been thinned at bloom, and compared with unthinned spurs on the same trees. Fruit Ca concentrations, primary spur leaf areas and primary spur leaf areas per fruit were greater for spurs bearing a single fruit (achieved by thinning manually or through natural abscission) than for multi-fruited spurs on the same trees. Spurs bearing one fruit on unthinned trees had greater fruit Ca concentrations, primary spur leaf areas and primary spur leaf areas per fruit, but lower fruit weight than the same spurs on alternate-cluster thinned trees. However, spurs on unthinned and alternate-cluster thinned trees with the same primary leaf areas per fruit had similar final Ca concentrations. Fruit size and crop loads were found not to be important in explaining fruit Ca concentration differences between thinning methods. However our results suggest that thinning method may affect Ca accumulation in apple fruit by altering the relationship between fruit numbers and leaf areas on individual spurs.  相似文献   

14.
Floral bud development, early fruit set, bud size, leaf nitrogen and shoot starch content were recorded in spring, summer and autumn shoots of ‘Hass’ avocado (Persea americana Mill.). Floral initiation occurred in late autumn, but only in buds on terminal shoots (the last-formed shoot module on a terminal or axillary growth axis). In branching systems with three growth flushes, more flowers were produced and more fruit set on autumn and summer, than on spring flush terminal shoots. Floral development and leaf nitrogen accumulation occurred later in autumn than in summer shoots, but leaf numbers, dry and fresh weights, starch content of wood, mean floral status at anthesis and anthesis date were similar. The results suggest that nitrogen and starch were present in excess during floral development, and that shoot age did not influence the ability of a shoot to flower and set fruit, provided the shoot had sufficient vigour to produce new shoot growth in spring.  相似文献   

15.
Fruit from Granny Smith, Fyriki, Fuji Kiku 8, and Imperial Double Red Delicious apple (Malus domestica Borkh.) trees planted in single or double rows, were harvested from different positions in the canopy, during the last month before commercial harvest. Fruit physico-chemical and antioxidant capacity, using the radical DPPH, were measured, in skin and flesh tissue. Greater total phenol content and total antioxidant capacity per fresh weight and serving portion of skin and flesh tissue, were found in Imperial Double Red Delicious and Fyriki apples, compared to Granny Smith and Fuji Kiku 8. The variation among cultivars in antioxidant contents was greater in peeled, compared with unpeeled fruit, highlighting the importance of eating unpeeled fruit. During the last two weeks before commercial harvest the total phenol content and total antioxidant capacity per fresh weight increased in skin of Granny Smith (by 24% and 42%, respectively) and Fuji Kiku 8 (by 19% and 27%, respectively). Fruit from the more sun—exposed parts of canopy had usually better red coloration and the effect was more pronounced in Fuji Kiku 8 and Fyriki, followed by Imperial Double Red Delicious and a lower effect was found in Granny Smith. Greater total soluble solid content, but not flesh firmness, were also found in fruit from the more sun—exposed parts of canopy, in all cultivars. The skin of fruit from the upper positions in the canopy had greater total phenol content and total antioxidant capacity, in all cultivars, apart from Fyriki. Antioxidant contents in flesh tissue were also greater in the upper positions of canopy in Fuji Kiku 8 and Imperial Double Red Delicious, and to our knowledge this is the first report on plant canopy effects on apple flesh antioxidant compounds.  相似文献   

16.
Summary

Fruit of three Annona species, viz. cherimoya (A. cherimola Mill), sugar apple (A. squamosa L.) and custard apple (atemoya, Annona X) were ripened in ethylene-free air and under propylene. Differences were found in patterns of respiration, ethylene production and fruit firmness changes during ripening. Cherimoya and custard apple fruits showed two successive rises in respiration rate whereas sugar apple fruits showed only one. Ethylene production showed one main peak but the onset of rapid ethylene production occurred after the beginning of the respiration climacteric in all three species. Custard apple fruit had acceptable eating quality (as judged by sensory assessments and chemical analyses of pulp) for up to four days after first detectable softening, when ripened at 20°C in ethylene-free air or under propylene. Fruit ripened in ethylene-free air had better ripe fruit quality than fruit ripened under propylene.  相似文献   

17.
Summary

This study aims to quantify the effects of fruit crop-load on flowering and to determine the relationships between flowering and phloem sap carbohydrate and nitrogen content fractions from budding to dormancy in ‘Zincal 5’ nectarine. Fruit load significantly reduced the number of flowers per tree both indirectly, by reducing the number of shoots per tree and the number of nodes per shoot, and directly, by reducing the number of floral buds per node. The intensity of the response depended on the number of fruits developed per tree. Trees that kept all fruits up to senescence flowered 35% less than trees thinned by hand to 40% of fruits at pit hardening, and 55% less than trees completely thinned in bloom by hand. Trees that kept all fruits had significantly lower glucose and sorbitol contents in the phloem sap of mixed branches up to harvest date and full vegetative growth, respectively, but no significant relationships were found between the concentrations of these carbohydrates and flowering intensity in the following Spring. Sucrose and fructose did not show any significant difference in regard to crop-load. In fibrous roots, starch content was not related to fruit load up to dormancy, indicating that starch content is not associated with flower bud induction and differentiation. The nitrate-nitrogen fraction was significantly higher, and the ammonium-nitrogen fraction was significantly lower, in trees that tended to flower less, suggesting some disturbance in nitrate reduction in these trees.  相似文献   

18.
Summary

The effects of different timings of fruit thinning at the lower nodes (nodes 4 to 7) on fruit growth and abortion at higher nodes were investigated in a gynoecious, parthenocarpic cultivar of cucumber (Cucumis sativus L.), ‘NK x AN8’. Fruits at the lower nodes were removed 0, 5, 10, 15 and 20 d after anthesis of flowers at node 8 (DAA8).

Total leaf areas and growth patterns of individual fruit were then monitored. When fruits at nodes 4 to 7 were thinned 0 or 5 DAA8, all fruits at nodes 8 to 12 grew to commercial size, without fruit abortion. When fruits were thinned 10 DAA8, the fruits at nodes 8 to 12 ceased to grow after anthesis, but growth was restored a few days after fruit thinning. Fruit thinning at 15 or 20 DAA8 forced most fruits at nodes 8 to 12 to abort, while fruits at node 13 and above ceased to grow for a while, but resumed growth after fruit thinning. In all treatments, total leaf area increased with time throughout the experiment. High fruit load depressed the rate of growth of leaf area slightly, 65 to 75 d after sowing. Fruit load (fresh weight) per leaf area was about 50 mg cm–2 just before fruits at nodes 4 to7 were thinned at 20 DAA8.These results suggest that fruit abortion occurs if fruits at the lower nodes persist for a long period, and fruits at the middle nodes senesce before enlargement. Fruit thinning at the lower nodes can restore the growth of fruits in the stagnant growth phase within 10 d.  相似文献   

19.
Summary

The effect of tree density (2000, 2667, and 4000 trees per ha) and the ratio of between to within-row distance (1:1, 2:1, and 3:1) on light interception, fruit production, colour and individual fruit weight was evaluated in a ten-year comparative field study with apple at two sites in The Netherlands (51° 30′ and 52°0′ N) and one site in Denmark (55°30′). For each combination of tree density and rectangularity, trees were pruned at three heights (1.50, 1.88, or 2.25 m). Fruit production over nine years and seasonal incoming radiation between bloom and harvest were 20 and 15% greater in The Netherlands. Climate-based estimates of potential production as provided by a crop-growth model, predicted 18% higher fruit production in The Netherlands. Production was proportional to light interception and increased with tree density, but the amount of well-coloured fruit per ha in later years did not increase with planting density. With more than 70% light interception in later years, a large proportion of shade within the canopy was found. Fruits were smaller and less coloured at the Danish site. Fruits were more coloured in the taller and more open trees, even at the highest tree densities. Plantings with 1:1 and 2:1 between-to within-row distances intercepted more light and had a more uniform light distribution than 3:1 designs. This led to higher fruit production and better fruit colour. Fruit weight was not influenced by tree density, rectangularity, or tree height.  相似文献   

20.
Summary

The effect of hydrostatic pressure on water uptake by sweet cherry fruit (Prunus aviumL.) was studied to establish whether ¯ow through stylar scar, pedicel/fruit juncture or stomata are factors in water uptake. Hydrostatic pressure was varied by submerging fruit in deionized water for 0.25.h at different depths (0.03 to 1.85.m equivalent to hydrostatic pressures of 0.3 to 18.1.kPa in addition to air pressure). Water uptake was determined gravimetrically. Increasing hydrostatic pressure increased water uptake and percentage of stomata penetrated by an 0.1% (w/v) acridine orange solution (surface tension 71.mN m±1). Water uptake and percentage stomata penetrated were positively related. Fruit that cracked during immersion had a somewhat higher uptake than fruit free of visible cracks. The effect of pressure was qualitatively similar for early and mature stage III fruit, but uptake at 0.3 and 5.0.kPa was higher for mature stage III fruit. The higher uptake at low pressure in mature stage III was related to water ¯ow through the pedicel/fruit juncture, since sealing the juncture markedly reduced uptake. Sealing the stylar scar had no effect on water uptake. Extrapolating the uptake/pressure relations to zero pressure revealed that water uptake into mature crack-free fruit wetted by a hypothetical thin continuous water film on the surface would occur through the pedicel/fruit juncture, the cuticular membrane and, possibly, a small fraction of infiltrated stomata.  相似文献   

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