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1.
《Scientia Horticulturae》2002,92(2):125-135
The influence of pre-blossom temperatures on flower development and fruit set is ascertained in apricot (Prunus armeniaca L.), a species without previous records on the effect of pre-blossom temperature on fruit set, but that is particularly prone to erratic fruit set. A polyethylene cage was used during pre-blossom development of flower buds to increase maximum temperatures by 6–7 °C and mean temperatures by 3 °C in orchard conditions. This increase in temperature accelerated flower bud development, caused a hastening in flowering time and following hand-pollination, reduced fruit set. At anthesis, flowers that had developed in warmer conditions weighed less and showed less development of the pistil than control flowers. Pistil growth of flowers under warm conditions did not differ from that of the control flowers when both the populations were compared on a real time scale in spite of the fact that warmed buds were at an advanced external phenological stage. Thus, hastening of external floral development by warm pre-blossom temperatures was not accompanied by advance in pistil development. This lack of synchrony resulted in premature flowering of flowers with underdeveloped pistils that had a reduced capability to set fruit. The results are discussed in terms of flower quality and its implications in fruit set and subsequent crop load.  相似文献   

2.
Flower emasculation is commonly used to make flowers unattractive to pollinating insects and to carry out controlled pollinations. In sweet cherry, we have observed recurrent low fruit set after flower emasculation and compatible pollination without apparent causes. This led us to evaluate its effect on the progress of the reproductive phase and on fruit set in this species. Flower emasculation reduced by more than a half the fruit set obtained in crosses made during two consecutive years. This effect could be traced back to the first week after anthesis where weight increase of pistils from emasculated flowers was smaller and ovule degeneration was accelerated compared to pistils from non-emasculated flowers. Pollen tubes, which behaved similarly at the stigma-style level in emasculated and non-emasculated flowers, lost their directionality in the area close to the degenerated ovule in the ovary. While flower emasculation is valid to evaluate pollen tube performance in the style and to determine incompatibility relationships, the lower fruit set registered after emasculation alerts on its use in fruit set experiments and breeding programs.  相似文献   

3.
A typical olive (Olea europaea L.) inflorescence consists of about 20 flowers. However, in many cultivars, only one fruit develops. This is due to massive abscission of flowers and fruitlets, which occurs during the first month after anthesis. In this study, we used the olive cultivar 'Barnea' to characterize the abscission mechanism and to try to increase fruit set by increasing the number of developed fruit per inflorescence. Removing the lateral flowers 3 weeks before anthesis increased fruit set by more than 50%. Removing all inflorescences but one from a branch increased the number of developed fruits from 0.93 to 2.8 during 2017 and from 0.91 to 3.34 fruits per inflorescence in 2018. Sugar quantification in the pistil revealed that starch level is high on the day of anthesis and low 25 days later in abscised as well as in developed fruit. Soluble carbohydrates are low on the day of anthesis, low in abscised flowers/fruitlets 25 days after anthesis and high in developed fruit. Screening the natural variation found in the Israeli germplasm collection revealed that in most cultivars less than one fruit per inflorescence has developed. However, there are unique cultivars with a higher fruit set.  相似文献   

4.
王男麒  彭良志  邢飞  周薇  曹立  黄翼  江才伦 《园艺学报》2013,40(12):2489-2496
 以成年纽荷尔脐橙、兴津温州蜜柑和沙田柚为材料,研究落蕾、落花和脱落幼果中的养分 含量及其脱落造成的损耗。结果表明,3 个品种的蕾和花营养元素含量为N 3.34% ~ 3.66%,P 0.26% ~ 0.31%,K 1.67% ~ 2.30%,Ca、Mg 和S 含量0.17% ~ 0.48%,Fe、Mn、Zn、Cu 和B 含量8.1 ~ 87.5 mg · kg-1。 除花的B 含量显著高于蕾外,花和蕾的多数营养元素含量相近,且品种间差异小。与蕾和花相比,幼果 的N 和P 含量较少,N 和P 含量分别少21.8%和19.5%,但Fe 含量较多,其它营养元素含量变化不明显。 纽荷尔脐橙、兴津温州蜜柑和沙田柚单株脱落的蕾、花和幼果干物质量合计分别为3 016.3 g、3 533.6 g 和1 486.7 g,由此所造成的单株主要养分损耗为N 49.2 ~ 119.4 g、P 4.3 ~ 10.1 g、K 30.1 ~ 76.2 g、Mg 2.5 ~ 7.1 g、Zn 24.0 ~ 81.5 mg 和B 65.5 ~ 170.2 mg。兴津温州蜜柑和沙田柚均以落花的养分损耗最大,落蕾其 次,落果最小;纽荷尔脐橙则是落花和落蕾的养分损耗相近且远高于落果。品种间以兴津温州蜜柑脱落 的养分损耗最大,纽荷尔脐橙其次,沙田柚最小。因此,柑橘应控制过量开花,并在萌芽开花期及时补 充养分。  相似文献   

5.
Starch as an important reserve carbohydrate plays in deciduous fruit species an important role in frost resistance of the wood during winter as well as of flowers during spring frosts. Also during development of flowers the deposition of starch, e.g. in the conducting tissue of the style and in pollen grains is evident. This starch accumulation in the reproductive flower parts seems to be important for fertilization and thus fruit set. The investigations presented should contribute to elucidate the dynamic of starch accumulation in the different organs of a flower bud in apple, from the beginning of bud differentiation until anthesis. The sampled buds were sectioned after embedding in plastic material. Starch accumulation was determined by image analysis. In the four apple cultivars ‘Boskoop’, ‘Elstar’, ‘Golden Delicious’ and ‘Pinova’ starch deposition could be observed already shortly after beginning of flower bud differentiation in July/August in the calyx, corolla, anthers and ovary. Until autumn, starch content increased considerably, it showed during winter some fluctuations according to flower organ, and decreased again towards the flowering season, presumately by conversion to sucrose, as shown in the wood in relation to frost resistance. This decrease seems to be related to the energy demand which is needed for flower development, fertilization and early fruit development.  相似文献   

6.
The effective pollination period (EPP) of durian was determined by both delayed and bud pollination, during which reproductive factors affecting the EPP, e.g., stigma receptivity, pollen tube growth in the style, and ovule longevity were studied histologically. This study was conducted in three distinct locations in Thailand, namely, the Chantaburi Horticultural Research Center and two private orchards in Chantaburi and Trat provinces. Results from artificial pollination revealed that at anthesis, the durian flower is receptive and has a high fruit set ratio. A mean fruit set of 50% was obtained at anthesis in the private orchard in Chantaburi province. However, the EPP of durian was found to be very short, lasting for only one night; the fruit set from pollination on the morning after anthesis ranged from 0% to 3.4%. No fruit set occurred following pollination 24 or more hours after anthesis. When compared with the flowers of other fruit species, the durian flower has a unique feature in that it blooms overnight; the following morning, there is abscission of all parts of the flower, except the gynoecium. Thus, EPP appears to be synchronized with flower longevity. On the other hand, the durian flower was receptive several hours before anthesis. The results of chemical tests, including the hydrogen peroxide test and Perex-Test®, for the evaluation of stigma receptivity appeared to be in agreement with the EPP. However, fluorescent microscopy revealed that pollen could germinate even in the stigmas pollinated 48 h after anthesis, but the number of pollen tubes at the top of the style rapidly decreased from 34.6 (at anthesis) to 0.5 (48 h after anthesis). A correlation test demonstrated a higher correlation coefficient between the fruit set and the number of pollen than that between the fruit set and the result of Perex-Test®. This indicated that pollen tube penetration or elongation in the style was inhibited, probably due to the deterioration of nutritional support from the pistil to the pollen tubes; this can be a limiting factor of the EPP in durian.  相似文献   

7.
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   

8.
Summary

Several pollination studies carried out on different, self-incompatible almond cultivars and seedlings have shown the presence of variable levels of fruit set following self-pollination that could be attributed to partial self-incompatibility (PSI). PSI is an intermediate reproductive behaviour, described in some angiosperm species, which indicates that self-incompatibility is a quantitative and plastic trait. The present study was performed to substantiate the occurrence of PSI in almond by studying ten cultivars that are traditionally considered to be self-incompatible (four of which had previously shown fruit set after self-pollination). These cultivars were analysed by microscopic observations of the progression of pollen tubes through the pistil following controlled self-pollination, determinations of fruit set after bagging flower buds, and molecular identification of the parentage of the fruits obtained using consensus PCR-primers for Prunus S-RNase alleles. The results showed that, in nearly all cases, the pollen tubes did not enter the ovary and, from a total of 5,349 bagged flower buds, only 17 fruits were obtained. In all cases, PCR analysis of the plants obtained after germination of these seeds showed a band corresponding to an S-RNase allele not present in the maternal progenitor, clearly indicating that they could only have arisen from cross-pollination.Therefore, the low fruit set values observed in some of the cultivars studied were not due to a breakdown in the self-incompatibility response that confers PSI, but to very low rates of contamination with foreign pollen. These results corroborate the self-incompatibility phenotype of the cultivars studied here, and highlight the importance of ascertaining the identity of the parentage in any progeny obtained after bagging.  相似文献   

9.
In forcing the strawberry cultivar ‘Glasa’ under poor light conditions in the glasshouse, a sharp drop in light intensity, leading to a low light level for some days, resulted in stamen abortion in those flower buds which were due to open in a few days. This in turn led to poor fruit set.Under controlled light conditions stamen abortion was found to occur when the light intensity dropped to 4400 mW/m2 or less.  相似文献   

10.
Flower initiation date and readiness to flowering in buds of different age were studied in ‘Fino de Jete’ cherimoya (Annona cherimola) cultivar in order to establish the limits for the manipulation of its flowering date. Flower initiation was analyzed by light and scanning electron microscopy (SEM) collecting axillary buds from May to the following February, whereas the bud readiness to produce perfect flowers was determined by forcing buds of different age to sprout by means of leaf removal and tipping the new growth. SEM images confirm that cherimoya buds are differentiated into flowers almost a year before blooming. In this regard, axillary buds have already formed the sepals when the subtending leaf has just begun unfolding (week 0), while the petals are clearly visible in 1-week-old buds. Sectioning of paraffin-embedded buds illustrate that cherimoya buds are in fact a bud complex that 1 week after its inception comprises 4–5 buds of different size of which the two largest ones are reproductive, while the 2–3 smallest buds often remain undifferentiated at that time. The high capacity of flowering expressed by young buds that have been forced to grow proves that cherimoya meristems are early competent for flowering. No differences in fertility or in the time needed to reach anthesis after leaf removal were found among buds of different ages. Node position had no effect on bud break and flowering potential. The early flower initiation in cherimoya deduced from this work opens a wide temporal window for the experimental manipulation of flowering and harvest dates in this crop.  相似文献   

11.
Single spray applications of 100 ppm of a mixture of the gibberellins A4 and A7 (GA4 + 7) were made on fruiting spurs of the apple cultivar Cox's Orange Pippin to investigate the effect on set, June drop and growth of fruits, as well as on shoot development and flower-bud formation on the bourses. Applications were made from 1 to 50 days after full bloom following partial hand-pollination of flowers, i.e. two stigmas per flower pollinated. In another experiment applications were made from 1 to 20 days after full bloom following complete (five stigmas per flower) or partial (two stigmas per flower) hand-pollination, after open pollination, or on emasculated flowers.GA4 + 7 only temporarily increased fruit set after open pollination or after effemination of flowers, and then only after application 1 day after full bloom. GA4 + 7 did not affect the very high fruit set after complete or partial hand-pollination. Both latter pollination treatments induced an equally high fruit set.GA4 + 7 reduced June drop significantly whenever fruits were left after first drop, except after early applications following open pollination. GA4 + 7 was effective in June-drop reduction up to 40 days after full bloom, i.e. until the onset of the June drop.Fruit size was not clearly affected by GA4 + 7. The smaller fruits obtained in some cases after GA treatment could be explained by assuming that maturity was reached by fruits that would have abscised without an exogenous GA4 + 7 supply. GA4 + 7 also increased seed abortion. Fruit length was increased by GA4 + 7 only for applications made up to 20 days after full bloom.GA4 + 7 stimulated bourse-shoot development to some extent. Flower-bud formation on the bourses was not clearly affected by GA4 + 7, but was markedly influenced by the presence of fruits.That GA4 + 7 reduced June drop so much in spite of a slight promotive effect on bourse-shoot growth and a slight abortive action on seeds suggests that these gibberellins may be specific stimuli for apple-fruit growth after actual fruit set is achieved.  相似文献   

12.
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   

13.
Periodic seismic (shaking) stress influenced the growth of sexual and asexual reproductive structures of three cultivated species. It delayed anthesis of Lycopersicon esculentum Mill. 'Patio' but not of Tagetes erecta L. 'Jubilee' or Solanum tuberosum L. 'Kennebec'. Shaken 'Jubilee' marigold plants produced the same number of flowers as undisturbed plants, but flowers of shaken plants were smaller. In contrast, seismic-stressed 'Patio' tomato produced fewer buds and flowers, but fruit set was enhanced relative to that of controls. Seismic stress also reduced tuber weight of 'Kennebec' potato, whereas tuber number was unaffected. The overall effect of seismic stress was to reduce the growth of reproductive structures and, in some cases, the number of reproductive structures that developed.  相似文献   

14.
Hand pollination, flower-shaking or tripping of the keel petals, was necessary to obtain adequate self-pollination of Spencer type sweet peas in glasshouses.

The effect of low light intensities on fruit-setting was studied by growing plants under muslin of different weaves. During long days a small but significant increase in the fertility of a summer-flowering variety of sweet pea occurred on plants shaded by thin muslin, provided that high temperatures and minimal soil watering were maintained. The more intense the shading treatment, the greater was the amount of flower-bud abortion and this abortion was responsible for lower yields of fruits per plant. A significantly smaller number of flowers set fruit as a result of a heavy watering treatment that led to a slight waterlogging in the pots.

By comparing the fruit-setting rate with temperatures which prevailed in a series of five-day periods in spring and summer, it was found that, for unit rises of temperature, the setting rate increased exponentially. A regression equation was computed for the prediction of setting rates.

Low temperatures in the week before anther-dehiscence were found to depress fertility, no matter how favourable the post-pollination temperatures.  相似文献   

15.
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   

16.
薛林宝 《园艺学报》2000,27(6):458-459
甜椒植株摘去 50 %叶片比不摘叶处理生物学产量大幅下降 ,落果率高。初果生长速率在相同节位和相同时期 ,摘叶和不摘叶间表现相似 ,初果坐果节位为 5和 7的生长速率最大 ,其第 10节位试验果落果率最高。无性器官与试验果的生长量之和与试验果落果率呈直线相关。  相似文献   

17.
宋婷婷  田佶  张杰  卢艳芬  姚允聪 《园艺学报》2014,41(5):1045-1046
观赏海棠‘缨络’系从‘亚当’（Malus‘Adams’）种子实生后代中选育出的新品种。树势较强,树姿较直立。一年生枝和幼叶红褐色,成熟叶浓绿色;花蕾深红色,开放后花瓣红色,花期偏晚;果实长圆锥形,整齐度好,果实底色浅绿色,果面盖色深红色,部分着色,色泽艳丽。花、果、叶颜色鲜艳,观赏价值高,抗寒和抗病性强。  相似文献   

18.
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   

19.
钙化合物对苹果疏花疏果的效应   总被引：11，自引：0，他引：11  
选用蚁酸钙制剂(CFA)、氯化钙制剂(CCOA)、硝酸钙制剂(CNOA)、丙酸钙制剂(CPA)、氯化钙(CaCl2)、硝酸钙犤Ca(NO3)2犦六种钙化合物对红富士苹果进行了疏花疏果试验。结果表明,以浓度为5～10g/L的蚁酸钙制剂效果最好;喷布两次比一次效果好,第一次在顶芽中心花盛开3d后喷布,第二次在顶芽中心花盛开5d后喷布,这样可确保顶芽中心花不受影响,而使顶芽侧花和腋芽花的结果率同时降低。CFA加用1mL/L的界面活性剂KP-4714,可显著提高疏花效果。所用钙化合物的疏花喷布对幼果生长和成熟果的大小、着色程度、果实品质均无不利影响。浓度为10g/L的氯化钙和硝酸钙处理对新梢生长点和幼叶有药害发生。  相似文献   

20.
Gladiolus plants cultivar ‘Spick and Span’ were grown in winter under natural short day (SD) or under long day (LD), with 4 hours low intensity light at midnight. Growth of the various organs was followed by periodic sampling. SD promoted flower development and advanced anthesis but reduced the final size of the flower. LD increased weight and size of leaves and flowers.Initial growth of the corm was similar under both photoperiods, but while corm growth continued throughout the growing-period under SD, it was checked under LD when flowers were developed at an enhanced rate and until anthesis. At this stage, the allocation of assimilates was directed towards the flower sink and away from the corm sink.Final corm weight was also promoted by LD. This is interpreted as an indirect effect due to increased photosynthesis of the larger LD plants. In non-flowering plants raised from cormels, SD specifically promoted corm growth, although no competing flower sink was present.It is concluded that photoperiod affects growth and development of gladiolus in two ways: directly — by affecting the partitioning of assimilates between the flower or the corm; and indirectly — by affecting the total photosynthates available to the plants by influencing foliage size and the total growth period.  相似文献   

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