Changes in physicochemical attributes of sweet pepper cv. Domino during fruit growth and development

The effect of harvesting sweet pepper ‘Domino’ fruit at different stages of growth and development on physicochemical attributes was studied. The suitability of fruit fresh weight, diameter and length, weeks from anthesis, total soluble solids (TSS), fruit colour change, firmness, internal CO₂ and C₂H₄ concentrations as well as fruit respiration and ethylene production as maturity indicators were evaluated. Fruits were harvested weekly until fully red ripe. Fruits took 8 weeks after anthesis (WAA) to reach harvest maturity and a further 2–3 weeks to reach full ripeness (11 WAA). Fruits exhibited a sigmoid growth pattern. Hue angle (change in colour from green to red) declined with time while chroma (colour intensity) values increased with fruit maturity, as did TSS. An increase in PⁱCO₂ and PⁱC₂H₄ accompanied the decrease in hue angle. The association between fruit ripening and the significant increase in PⁱC₂H₄ indicates that ethylene may be responsible for ripening of this cultivar of sweet pepper. Colour change and TSS were reasonable indicators of maturity of sweet pepper fruit complemented with fruit firmness.     

The Effects of Manurial Treatments on the Chemical Composition of Gooseberry Bushes.: I. Effects on Dry Matter,Ash and Ash Constituents of Leaves and Stems of Terminal Shoots and of Fruits; and on Total Nitrogen of Fruits.

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.     

Comparison of changes in sugars and ethylene production of cherimoya fruit grown at different seasons

Summary

Changes in fruit weight, total soluble solids (TSS), sugar content and postharvest ethylene production during fruit development were compared on fruit of cherimoya (Annona cherimola Mill., cv. Big Sister) pollinated at different times (early, at the beginning of April, 1995 and late, at the end of May, 1994). Fruit weight increased by growth, independently of pollination times. Changes in TSS and sugar content were strongly affected by pollination time. In late pollinated fruits, both TSS and sugar content increased during the growth period, 110–160 d after pollination, while neither increased with fruit growth in early pollinated fruit. Moreover, changes in TSS and sugar content after ripening depended not only on pollination time but also on the growth period. With late pollination, fruit harvested after 140 d became edible after ripening. The TSS and total sugar contents, (the sum of fructose, glucose and sucrose contents) increased to about 20° Brix and above 16%, respectively. But early pollinated fruits were not edible after ripening, since total sugar content increased only to about 7%, even though they kept growing for 160 d on the tree. The maximum rate of ethylene production declined and the number of days to the ethylene peak from harvest is also reduced with growth in both cases. These changes were closely correlated with days after pollination (r>0.9) regardless of pollination time. Comparisons of accumulated temperature suggest that temperature at pollination time and during the resting period of growth affected fruit development. These results indicate that neither fruit weight nor number of days after pollination is a suitable index for harvesting time.     

Comparative effects of regulated deficit irrigation (RDI) and partial root-zone drying (PRD) on growth and cell wall peroxidase activity in tomato fruits

The effects of regulated deficit irrigation (RDI) and partial root-zone drying (PRD) on tomato fruit growth and cell wall peroxidase activity in tomato exocarp were investigated in growth chamber conditions. The RDI treatment was 50% of water given to fully irrigated (FI) plants and the PRD treatment was 50% of water of FI plants applied to one half of the root system while the other half dried down, with irrigation shifted when soil water content of the dry side decreased 15–20%. RDI significantly reduced fruit diameter, though PRD reduced fresh weight while having no significant effect on fruit diameter. The activity of peroxidase was significantly higher in RDI and PRD treated plants compared to those of FI. Differences between RDI and PRD were expressed on temporal basis. In the fruits of RDI treated plants peroxidase activity began to increase in the phase when fruit growth started to decline with the peak of enzyme activity of 6.1 HRPEU g⁻¹ FW reached in the phase of mature green fruits when fruit growth rate was minimal. Increase of peroxidase activity in PRD fruits coincided with the ripening phase and the peak of enzyme activity (5.3 HRPEU g⁻¹ FW) was measured at the end of fruit ripening. These data potentially identified contrasting and different roles of tomato exocarp cell wall peroxidase in RDI and PRD treated plants. In RDI treated plants peroxidase may have a role in restricting fruit growth rate, although the increase in enzyme activity during ripening of PRD treated fruit pointed out that peroxidase may also control fruit maturation by inducing more rapid process.     

Ethylene production throughout growth and development of plants

Ethylene production by 10 or 20 m2 stands of wheat, soybean, lettuce, potato, and tomato was monitored throughout growth and development in an atmospherically closed plant chamber. Chamber ethylene levels varied among species and rose during periods of canopy expansion and rapid growth for all species. Following this, ethylene levels either declined during seed fill and maturation for wheat and soybean, or remained relatively constant for potato and tomato (during flowering and early fruit development). Lettuce plants were harvested during rapid growth and peak ethylene production. Chamber ethylene levels increased rapidly during tomato ripening, reaching concentrations about 10 times that measured during vegetative growth. The highest ethylene production rates during vegetative growth ranged from 1.6 to 2.5 nmol m-2 d-1 during rapid growth of lettuce and wheat stands, or about 0.3 to 0.5 nmol g-1 fresh weight per hour. Estimates of stand ethylene production during tomato ripening showed that rates reached 43 nmol m-2 d-1 in one study and 93 nmol m-2 d-1 in a second study with higher lighting, or about 50x that of the rate during vegetative growth of tomato. In a related test with potato, the photoperiod was extended from 12 to 24 hours (continuous light) at 58 days after planting (to increase tuber yield), but this change in the environment caused a sharp increase in ethylene production from the basal rate of 0.4 to 6.2 nmol m-2 d-1. Following this, the photoperiod was changed back to 12 h at 61 days and ethylene levels decreased. The results suggest three separate categories of ethylene production were observed with whole stands of plants: 1) production during rapid vegetative growth, 2) production during climacteric fruit ripening, and 3) production from environmental stress.     

青海高原核桃果实油脂和生长动态变化分析

以地方核桃为试材,拍照记录果实外观形态变化,并对不同发育时期果实质量、果实纵横径、坚果质量、种仁质量、出仁率、油脂含量和成熟种仁中脂肪酸组分等进行测定,以期明确青海高原核桃果实油脂和生长动态变化。结果表明:随着核桃果实生长发育,果实质量、果实纵横径、坚果质量、种仁质量、出仁率、油脂含量等指标总体呈上升趋势,其中果实质量在成熟后期略有下降,并依据指标建立了核桃果实生长发育的数学模型。7月中旬油脂开始积累,并逐渐增加,至果实成熟时种仁中的油脂含量达到最大值69.4%,种仁中主要脂肪酸是棕榈酸、硬脂酸、油酸、亚油酸和亚麻酸,不饱和脂肪酸含量可达91.7%。9月中旬核桃果实充分成熟,且油脂含量最高,是最佳采收时期。可根据核桃果实形态、果实生长曲线和数学模型来判断果实发育时期,采取合理的栽培管理措施,从而提高核桃果实的产量和品质。     

授粉和CPPU对猕猴桃内源激素水平及果实发育的影响

秦美猕猴桃花期不授粉,果实于花后５－２０ ｄ全部脱落。不授粉,但花前 ＣＰＰＵ处理,果实可延迟５ ｄ脱落,维持１６．７％的果不落,但果实于花后５ ｄ起停止发育。花后 ５－ １０ ｄ未授粉果 ＺＲｓ。ＧＡｌ＋３含量低于对照,但ＡＢＡ水平高于对照。花后２０ ｄ ＣＰＰＵ处理果实显著增大,对内源激素水平影响不大。处理后２０ ｄ内 ＺＲｓ、ＤＨＺＲ升高,处理后５ ｄ ＩＡＡ、 ＧＡＩ＋ ３下降, １０ ｄ后上升。 ＡＢＡ水平在花后６０－ １００ ｄ降低,采前升高。对种子、内源激素在果实发育中的作用进行了讨论。     

黄瓜单性结实果实发育与碳氮变化的关系

对黄瓜单性结实品系P 116 8和非单性结实品系UP 3315进行授粉和不授粉处理 ,P 116 8在不授粉的情况下 ,仍具有较好的结实性能 ,其单果质量、果长和果实体积均接近于授粉后生长的果实 ,非单性结实品系UP 3315在不授粉的情况下幼果在花后 3d(天 )就停止发育 ,不能形成产量。随着果实的生长发育 ,果实内碳、氮含量迅速增加 ,花后单果可溶性总糖和蛋白质含量与单果质量呈正相关关系     

‘红阳’猕猴桃自然生长果和CPPU处理果的生长发育动态

对广西桂北地区的‘红阳’猕猴桃自然生长果和CPPU处理果的生长发育进行研究,并对比两种果实的生长发育特点。结果表明,‘红阳’猕猴桃果实单果重、纵径生长变化呈"快速生长-较快生长-缓慢生长-较快生长"4个阶段,果实横径生长变化呈"快速生长-较快生长-缓慢生长"3个阶段;6月3日(落花45天)靠近果心的果肉开始转为红色,7月1日(落花75天)有少量种子变为黑色;果实的果心大小、干物质含量、可滴定酸含量的生长变化呈单曲线缓慢增大或增高趋势;果实果汁率的生长变化呈"高-低-高"趋势;果实可溶性固形物和全糖含量的生长变化呈"慢-快-慢-快"的"S"型增长趋势;在落花25天用10mg/L CPPU溶液处理幼果后,可促进果实生长膨大,提高内质,加快成熟,降低果实干物质含量,增大果心,但没有改变果肉和种子颜色的变化时间以及各指标生长峰值的出现时间,果实大小、内质的生长变化趋势基本和自然生长果的一致。     

优质鲜食橄榄新品种‘甜榄1号’选育研究

‘甜榄1号’是从大量橄榄实生树中选出的橄榄鲜食新品种。果实梭形,果皮黄绿色,纵横径3．0cm×1．7cm,平均单果重5．5g,果实可溶性固形物含量11．9％,可食率78．2％。在福建省闽清县,果实于11月中下旬成熟。果肉黄白色,肉质细嫩清脆,化渣,风味香甜,回味好,鲜食品质明显优于‘檀香’等现有主栽鲜食品种。     

Fruit growth and chemical properties of Ribes magellanicum “parrilla”

The aim of this work was to study the time course and pattern of fruit growth and the evolution of some of the chemical attributes such as soluble solids, acidity, and anthocyanin content in Ribes magellanicum plants growing in a natural environment near Ushuaia city, Tierra del Fuego (Argentina). Fruit growth and composition presented significant changes along the days from the full bloom phase. Fresh and dry fruit weight exhibited a typical double sigmoid curve. The first period of rapid fresh fruit growth was from full bloom phase until 28 days after, followed by a lag period until 42 days from the full bloom phase, and then by a second period of rapid increase until 56 days from the full bloom phase. Then, fresh fruit weight increased slowly (days 70–98 from the full bloom phase), reaching its maximum. Afterwards, fresh fruit weight decreased significantly until the end of the summer, and the fruiting period approximately ended 112 days from full bloom phase. On a dry weight basis the maximum fruit biomass was reached 98 days from the full bloom phase. Evolution of fruit growth was related with the compositional changes evaluated. By day 98 from the full bloom phase, soluble solids (17.5°Brix) and anthocyanin content (240.1 mg/100 g fruit fresh weight) were at their maximum, while at this time the total titratable acidity was at a minimum (0.4%). The results obtained not only contribute to the knowledge of the quantitative content of anthocyanin, a metabolite with nutraceutical value, but also give some tools for the definition of the optimal harvest time of R. magellanicum fruits, which it is important for fruit destination.     

The influence of growing season on fruit yield and quality of greenhouse melon (Cucumis melo L.) grown in nutrient film technique in a Mediterranean climate

Summary

The influence of growing season on some physiological and biochemical variates related to fruit yield and quality was investigated in melon (Cucumis melo L.) plants cultivated in nutrient film technique in a greenhouse located at Pisa, Central Italy, from mid-March to mid-June, or from mid-July to mid-September. Compared with spring, the plants grown in summer exhibited faster growth and development, but produced fewer fruits of larger size and poorer quality due to reduced sucrose content. Growing season did not affect total leaf area, but dry-matter production and partitioning to the fruits was significantly lower in summer than in spring. Summer fruit ripened within 30–35 d after anthesis, about 14 d fewer than in spring. Higher average temperature was presumably responsible for earlier fruit maturation in summer, as in both seasons all melons were harvested after 450–500 degree-days (base temperature of 12°C) from anthesis. Fruit swelling did not account for the reduction of sucrose content in summer-grown fruits, which instead was due to shortage of photoassimilate supply and inadequate sucrose synthesis, as suggested by the rate of leaf gas exchange and the activity of sucrose phosphate synthase in the fruit flesh, as determined during the final stages of fruit development. Lower solar radiation was presumably responsible for the reduced leaf carbon assimilation in summer, as growing season did not affect leaf turgor, stomatal conductance, mineral status and chlorophyll content.     

黄桃新品种‘徽黄’

 ‘徽黄’是从NJC83黄桃单枝变异中选出的早熟黄桃新品种,成熟期比NJC83黄桃提前7 ~ 10 d。果实近圆形,稍有果尖,缝合线中深,两半部较对称,果柄粗短,梗洼深广。平均单果质量156 g,最大210 g。果实成熟后果皮金黄,果尖及向阳面有红晕,果肉纯黄、无红色纤维,粘核,肉质弹性好,不溶质,具有香味,可溶性固形物10.3%,果实去皮硬度7.1 kg · cm^-2,酸甜适中,适于加工和鲜食。果实发育期83 d左右。丰产,适应性强。     

Fruit growth and pseudoembryo development affected by uniconazole,an inhibitor of gibberellin biosynthesis,in pat-2 and auxin-induced parthenocarpic tomato fruits

Morphological changes during the development of pseudoembryos in parthenocarpic fruits of the genetic parthenocarpic tomato cultivar, ‘Severianin’, were observed. Pseudoembryos that originated from division of the innermost integument cells were formed in the ovule cavity. These cells were highly stained with toluidine blue O and actively divided until 20 days after anthesis. Uniconazole, an inhibitor of gibberellin biosynthesis, applied at anthesis decreased the setting ratio of fruits and inhibited the development of pseudoembryos. Uniconazole applied at 3 days after anthesis inhibited fruit growth entirely and suppressed pseudoembryo development. Gibberellin treatment at 2 days after uniconazole treatment reversed the inhibitory effect of uniconazole on fruit growth and pseudoembryo development in ‘Severianin’. The inhibitory effect of uniconazole on fruit growth and pseudoembryo development in auxin-induced fruits of ‘Kyouryoku-Kyokkou’, a commercial cultivar without genetic parthenocarpy, was weaker than that in ‘Severianin’. Application of gibberellin also reversed the inhibitory effect of uniconazole in this cultivar. Well-developed pseudoembryos were always observed in the well growing fruit in both cultivars. These results indicate that the development of pseudoembryos is closely related to the growth of parthenocarpic fruit.     

葡萄新品种‘紫提988’

 ‘紫提988’为‘红地球’葡萄的枝变品种。果穗平均质量1 000 g,最大3 540 g。果粒椭圆形,紫红色,果粉厚,单粒平均质量14 g,最大26 g,大小均匀,含可溶性固形物13.9%,最高可达20%。果实生育期100 d左右。果实耐贮运,宜鲜食。抗性和适应性强。     

中晚熟油桃新品种‘京和油 2 号’

 ‘京和油2 号’是以‘25-17’（京玉 × NJN76）与‘2-2-94’杂交选育出的中晚熟黄肉油桃新品种。铃形花,无花粉。果实近圆形,平均单果质量201.2 g;果肉黄色,硬溶质,肉质细腻,风味甜,可溶性固形物含量12.0% ~ 14.5%。半离核,无裂核。丰产。果实发育期120 ~ 130 d。     

Effect of Leaf Number and Area on the Fruit Growth of Regular and Biennial Bearing Mango (Mangifera indica L.) Grown Under North Indian Conditions

Abstract

The optimum leaf number required for normal fruit growth in the regular bearing mango cultivar ‘Amrapali’ and the biennial bearing cultivars ‘Chausa’, ‘Dashehari’ and ‘Langra’ were studied by isolating individual fruits with known numbers of supporting leaves by shoot girdling at the time of fruit set. There were significant differences in the leaf area (249.01-1817.10 cm2), fresh weight (7.0-77.0 g) and dry weight (3.7-50.0 g) of leaves on shoots having 30, 20, 10 and 5 leaves as compared with control in different cultivars. In both types of cultivars, there was a progressive reduction in fruit size in terms of total fruit, pulp, peel, and seed weight with decreasing numbers of supporting leaves, however, a minimum reduction (2.4%) in fruit growth in ‘Amrapali’ was noticed with 30 supporting leaves. A nonsignificant difference in photosynthetic rate with varying number of leaves was found but its efficiency in leaves was higher in ‘Amrapali’ as compared with biennial bearing cultivars. Starch accumulation in the leaves was reduced by shoot girdling. The stomatal resistance of the leaves of girdled shoots was comparable with that of leaves on control shoots. In all the cultivars except ‘Amrapali’ it was observed that 30 leaves, the maximum retained on a shoot, could not support the growth of a single fruit to normal size. The data on rate of photosynthesis in different pool size of leaves and fruit growth in girdled and nongirdled shoots clearly show that fruit development depends not only on the current assimilates but also to a great extent on reserves. A 14CO2 feeding experiment showed a higher rate of carbon fixation in the leaves of girdled shoots than in the control shoots, but the translocation of 14C assimilated to the developing fruits on the girdled and control shoots was comparable. The results also indicated that developing fruits are major sinks for current photosynthates as more than 60 percent of the 14C exported from the treated leaf was found in the fruit in all instances.     

夏季剪枝对山地茄子农艺品质的影响

以茄子品种丰田一号为试材,研究了夏季剪枝对山地栽培茄子生长及品质的影响。试验结果表明,与对照相比,夏季剪枝对丰田一号的植株冠幅、茎粗、叶片大小等影响不显著,但剪枝后叶片鲜质量、干质量、叶绿素含量、优质果率及产量均显著提高(P<0.05),株高和劣质果率则显著降低,该研究为夏季剪枝技术在山地茄子栽培中的广泛应用提供了理论依据。     

脆肉网纹甜瓜新品种‘西蜜5号’

‘西蜜5号’为网纹甜瓜杂交一代品种。果实高圆形,单果质量1 200~1 500 g。果皮浅灰绿色,果面密覆网纹,网纹较粗,分布均匀,外形美观。果肉淡绿色,厚4.1 cm,平均可溶性固形物含量11.8%,果肉脆。中熟,全生育期100~105 d,果实发育期42~45 d。产量40 000~48 000 kg·hm~(-2)。耐低温、弱光,较抗霜霉病、白粉病,耐贮运。     

Sensitive stages of fruit and seed development of chili pepper (Capsicum annuum L. var. Shishito) exposed to high-temperature stress

The sensitivity of developmental stages to high temperature was investigated in chili pepper (Capsicum annuum L. var. Shishito). Plants were subjected to heat stress (38/30 °C day/night) immediately after anthesis for 5 or 10 days, or from 10 to 30 days after anthesis (DAA), from 30 DAA until harvest of the seeds, or immediately after anthesis until harvest of the seeds. Control plants were grown at 30/22 °C (day/night). Exposure to high temperature (heat stress) during different periods of development after anthesis adversely affected fruit growth, seed yield, and seed quality in chili pepper. Heat stress for the whole period after anthesis, and from 30 DAA until harvest reduced the growth period of chili fruits by 15 and 10 days, respectively. Heat stress from 10 to 30 DAA reduced fruit width and fruit weight. The early stage of seed development from anthesis until 10 DAA was sensitive to high temperature, which affected fruit length, fruit weight and seed set. Applying high temperatures to plants for 10 DAA increased the proportion of abnormal seeds per fruit. High temperatures from 10 DAA until 30 DAA inhibited carbohydrate accumulation and adversely affected seed germinability and vigor. These results suggest that the stage of development at which chili peppers are exposed to high temperatures is an important factor in fruit and seed growth and in seed quality.