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1.
To study the effect of pollination on fruit development in gynoecious and parthenocarpic cucumbers (Cucumis sativus L. cv. NK × AN8), the number of cells, cell size, mitotic index, histone H4 gene expression, and concentrations of endogenous cytokinins and auxin were compared in fruits that had developed from pollinated and non-pollinated flowers. Fresh weight was more in the pollinated group 4–12 days after anthesis (DAA) in both winter and spring, and 2–6 DAA in the summer. In winter, mitotic index increased from anthesis to 2 DAA and then decreased gradually in the pollinated group but immediately after anthesis in the non-pollinated group. Histone H4 gene in the pericarp zone was expressed more strongly during the period from pre-anthesis to 2 DAA in the pollinated group in summer. Concentrations of zeatin, isopentenyladenine, and indole-3-acetic acid (IAA) were higher in the non-pollinated group 2 and 4 DAA and peaked 4 DAA in spring whereas isopentenyladenine and IAA showed no distinct peaks in the pollinated group. These results are incompatible with the idea that pollination activates cell division by stimulating the synthesis of cytokinins and auxin in cucumber fruits. 相似文献
2.
Spathe regreening is a primary determinant limiting the postharvest quality for most hybrids of Zantedeschia, e.g. ‘Best Gold’, wherein the spathe commences regreening approximately two days after it is fully open. To identify an effective method to postpone the regreening, several synthetic plant hormones were evaluated for their influence on changes in color during regreening of discs excised from the spathe of ‘Best Gold’. The tested synthetic plant hormones included 6-benzylaminopurine (BAP), zeatin, N1-(2-chloro-4-pyridyl)-N3-phenylurea (CPPU) and GA3 at concentrations up to 0.1 mM. A concentration of BAP at 0.5 mM resulted in phytotoxicity symptoms on discs. Subsequently, the effect of a combination of BAP and GA3 on the regreening was examined. Application of the cytokinins (in particular BAP at 0.1 mM) or GA3 alone resulted in a one to five day delay in regreening on the spathe tissue. The most effective treatment in delaying regreening was from the simultaneous application of GA3 and BAP in a ratio of 1:1 (v:v) at 0.1 mM, wherein regreening was delayed for more than ten days. This treatment was then tested on the entire inflorescence, resulting in a delay in regreening for between seven and eight days. 相似文献
3.
茶树新梢内源玉米素的检测及分布 总被引：2，自引：1，他引：2
用反相液相色谱法测定了茶树新梢内源玉米素（Ｚｅａｔｉｎ）的分布。研究表明，茶树新梢内源Ｚｅａｔｉｎ水平为早生种＞中生种＞晚生种；顶芽＞腋芽；自然生长新梢＞剪采新梢；营养生长初期Ｚｅａｔｉｎ积累较多，随展叶数增加，其含量下降，至对夹三叶期，其含量仅为一芽一叶期的５２．１２％。内源Ｚｅａｔｉｎ含量与新梢生长速率呈正相关。 相似文献
4.
A low percentage of normal-looking embryos (20%) is still a problem in an efficient shed-microspore culture of hot pepper (Capsicum annuum L.) and it is more a serious problem in other androgenesic culture systems of pepper. Therefore, several factors were investigated to refine the protocol in order to increase the percentage of normal-looking embryos. The most important factors which improved the protocol and resulted in a significantly higher percentage of normal-looking embryos produces (>50%), were delayed enrichment of the liquid upper layer medium with 2.5 μM Zeatin and 5 μM IAA, and reduced incubation temperature from 28 °C to 21 °C, both after 3 weeks of culture. Addition of 1% activated charcoal in the solid lower layer of the medium enhanced the total embryo yield only, while an application of abscisic acid and increased osmolality medium had a detrimental effect on embryo production. The use of doubled haploid lines as anther donor plants has clearly decreased the variability and improved the statistical analysis of treatment effects. A higher percentage of normal embryos are produced with this refined protocol, and is therefore more suitable for implementation in the breeding programs of hot pepper. 相似文献
5.
Two experiments were conducted to investigate the effect of the Bacillus thuringiensis (Bt) transgene on gibberellic acid and zeatin contents and boll development in cotton using two types of Bt-transformed cultivars. In the 2003 study, boll size and weight, gibberellic acid 3 (GA3) and zeatin (ZR) contents were investigated from 3 to 45 days after flowering (DAF). In 2004, the flowers were sprayed with GA3, 6-benzyl adenine (6-BA) or a combination of both, and responses in boll size and weight, and endogenous GA3 and ZR contents were determined. In comparison to the common parent, Simian 4, overall boll size and weight were lower for the conventional Bt cultivar, Sikang 1, but higher for the hybrid Bt cultivar, Sikang 3. Similarly, the boll GA3 and ZR contents of Sikang 1 were lower than those of Simian 4, while those of Sikang 3 were higher than Simian 4. The largest difference between Sikang 1 and Simian 4 for boll GA3 and ZR contents were 18.5 and 25.5%, respectively, observed at 17 DAF. The largest difference between Sikang 3 and Simian 4 for boll GA3 and ZR contents were 25.5 and 85.7% at 31 DAF respectively. Application of GA3, 6-BA or a combination significantly increased boll size and weight for the conventional Bt cultivar and Simian 4, but did not have a significant effect on these characteristics of the hybrid cultivar Sikang 3. GA3 and ZR contents of the conventional Bt cultivar Sikang 1 were also significantly increased by application of these treatments. The combined application of GA3 and 6-BA tended to have a larger effect than the application of either of them separately, but the differences were statistically not significant. These results suggested that the lower boll GA3 and ZR contents, which could reduce boll nitrogen metabolism intensity, were responsible for the reduced boll development of the conventional Bt cultivar Sikang 1. 相似文献
6.
狗枣猕猴桃叶片离体培养的器官、体细胞胚形成与植株再生(英文) 总被引：1，自引：0，他引：1
以狗枣猕猴桃试管苗的叶片为外植体,接种于含3%蔗糖和0.2%Gelrite的BW培养基上,外加2,4-D(0,0.1,1和10μmol/L)与玉米素(0,1和10μmol/L)的12种激素组合,置于25℃,光周期为16/8h,光照强度为4000lx的条件下培养。在含1或10μmol/L2,4-D与1或10μmol/L玉米素组合的BW培养基上,产生了体细胞胚,并分化出小植株。随着玉米素浓度的增加,每个外植体上的胚再生频率和体细胞胚的数量也随之增加。同时以叶片为外植体产生的狗枣猕猴桃试管苗的愈伤组织表层产生了不定芽,并抽长成枝。发枝率随着玉米素浓度的增加而增加,并受高浓度的2,4-D所抑制。枝芽转接到含1μmol/LNAA的BW培养基上生根,长成小植株。 相似文献
7.
多效唑对猕猴桃离体试管苗生长及内源激素的影响 总被引：18，自引：0，他引：18
多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。 相似文献
8.
All processes that regulate of growth, differentiation and development and also stomatal movement are influenced by endogenous
hormones in plants. Research related with endogenous hormones is known for cultivated chickpea (Cicer arietinum L.), while in wild chickpeas no data existed. In this study, C. bijugum K.H. Rech.; C. chorassanicum (Bge) M. Pop.; C. cuneatum Hochst. ex Rich.; C. echinospermum P.H. Davis; C. judaicum Boiss.; C. pinnatifidum Jaub. et Sp.; C. reticulatum Ladiz.; and C. yamashitae Kitamura were evaluated for variations in endogenous plant hormone concentrations; indole-3-acetic acid, zeatin, gibberellic
acid, and abscisic acid in both leaf and pod. It was concluded that there was a great variation on endogenous plant hormones
among the annual wild Cicer species. The data may support selection for various attributes. 相似文献
9.
Some of the factors influencing the propagation of caper (Capparis spinosa L.) plants in vitro and germination of the seed were studied. The number of adventitious shoots emerging from caper stems cultured in vitro increased from 2.2 shoots per explant when the growth medium contained 2 mg/L of gibberellic acid (GA3) to 5.5 when the growth medium contained 2 mg/L zeatin riboside (ZR) and 1 mg/L naphthalene acetic acid (NAA). The best medium for callus formation from leaf and stem parts contained the growth regulators 1 mg/L 6-benzylaminopurine (BAP) and 0.1 mg/L NAA and the best medium for plant regeneration contained 1 mg/L kinetin and 0.1 mg/L indole-3-acetic acid (IAA). The effect of gamma irradiation on the growth of caper shoots in vitro was also studied. A 10 Gy dose of gamma irradiation stimulated growth of shoots up to 200% and increased shoot rooting percentage from 75 to 100%. 相似文献
10.
灌溉稻田水稻旱作法研究——水稻的生育与生理特性 总被引：13，自引：3，他引：13
以亚种间杂交稻两优培九（两系）及协优9308（三系）为材料，比较研究灌溉稻田旱作法与常规灌溉法水稻的生育与生理持性。结果表明，两杂交组合不因旱作改变全生育总叶片数，但播种至齐穗期因旱作缩短4～8 d，幼穗发育（拔节期）未见明显差别，说明旱作水稻生殖生长期相对缩短。旱作法水稻单丛叶面积大于常规灌溉稻，叶面积指数小于常规灌溉稻。水稻根系单丛干重因旱作比常规灌溉法水稻有明显增加，并营造了比常规灌溉法水稻根重根深的土壤环境。结果还表明,水稻旱作法有益于构建由大个体构成的高生物产量的群体，抽穗后生物产量占全生育期生物产量近40%；但是，旱作法对水稻也有诸多不利的生理影响，其一是比常规灌溉法水稻根系生理活性下降，表现在单茎根系伤流量、根系伤流液中玉米素含量、根系呼吸强度均较低；其二是灌浆-成熟期稻株剑叶光合速率低于常规灌溉法水稻，叶片气孔阻抗高于常规灌溉法水稻。因此，进一步提高灌溉稻田水稻旱作法的产量水平，其技术的主攻方向似应为提高稻株籽粒灌浆期间的生理素质，以提高成熟期的光合生产能力。 相似文献