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91.
The effect of auxins (IAA or IBA at 100,200,500 mg L 1) on rooting and sprouting parameters differed significantly (p < 0.05).Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments.The results of the present study revealed that rooting was significantly (p < 0.05) affected by the length of cuttings,as well as the position of shoots and type of cuttings.On average,86.0 per cent rooting was observed in the 30-cm long cuttings compared to the other two lengths of cuttings,i.e.,20 and 25 cm,irrespective of any auxin treatment.In a control set,without any auxin treatment,a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings.Similarly,cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively,irrespective of auxin treatments.Maximum rooting was observed in the lower portion (40.0%) of cutting compared to the upper portion (30.0%) in the control set without auxin treatment.Leafless branches produced maximum (72.0%) rooting compared to the leafy cuttings (35.0%),irrespective of the auxin treatment.The leafy cuttings produces a minimum of 15.0% sprouting and rooting in the control set. 相似文献
92.
落羽杉属种源研究:扦插生根能力变异 总被引:5,自引:0,他引:5
研究了不同种源、家系落羽杉扦插繁殖生根能力的遗传变异。结果表明,落羽杉嫩枝扦插一般7d开始产生愈伤组织,15d开始发根。活条率、生根率、发根数、不定根总长、生根力指数和抽梢长度等6个性状在种源、家系间均有显著或极显著差异。1600号、401号、502号和鸡公山种源是生长和生根能力兼优的种源家系。500×10-6NAA快浸可以显著提高落羽杉种源扦插生根率。同时还分析了扦插生根性状间及生根力与母树生长间的相关关系。 相似文献
93.
Both silver-sheet (a light reflector) and Figaron (a phytohormone), used individually, influence the production and abscission of reproductive organs during the reproductive stages of soybean. The combined use of silver-sheet and Figaron, however, has a much larger effect on production and abscission than the use of each alone. Experiments were conducted in the field at Niigata University, Japan, to investigate the light intensity at the canopy attributable to light reflection by silver-sheet and the individual and combined effects of silver-sheet and Figaron on reproductive abscission, yield and yield components of soybean. The field study was conducted on a sandy loam soil at 25 and 16 plants m−2 in 1999 and 2000. The results of the 2-year study indicated that Figaron had no effect on growth parameters, whereas silver-sheet had an effect. Flower production in the Figaron and Figaron + silver-sheet treatments tended to be lower than in the control and silver-sheet treatments. Silver-sheet increased the light intensity in the lower canopy of soybean through reflection, and thus the percentage of reproductive abscission in the lower canopy was lower in the silver-sheet treatments than in the other treatments. Greater pod set was observed in the middle and upper canopies than in the lower canopy in the Figaron treatments. Therefore, total pod set or pod number was greater in the combined silver-sheet and Figaron treatments. Yield and its components were greater at higher plant densities and tended to be greater in the combined treatments of silver-sheet and Figaron. The increase of yield components in the combined silver-sheet and Figaron treatments was believed to be a result of favourable light conditions and source–sink alterations in the canopy induced by Figaron. 相似文献
94.
95.
通过添加外源生长素,研究大花序桉离体根培养过程中的氧化酶的动态变化。结果表明:添加外源NAA和IBA,与无激素培养基间达到极显著差异;POD、IAAO和PPO影响离体根的形成,其中POD和IAAO活性在培养过程中呈下降→升高→下降的变化趋势,PPO的变化趋势与相反,呈升高→下降→升高趋势;3种氧化酶相互作用,从而维持、提高或降解内源激素含量,使细胞朝着有利于根的方向发展。 相似文献
96.
G. Daniel 《Plant Breeding》1993,110(3):259-261
The use of androgenetic doubled haploids in rye breeding is still limited by low regeneration rates. In this study we tested the influence of two modified MS-media on the number of reacting anthers and on plant regeneration. Picloram and 2,4-D were used as auxin components in the induction media. The highest induction rates (reacting anthers per 100 cultivated anthers) and the highest regeneration rates (number of green plants per 100 cultivated anthers) were reached on a modified MS-medium containing Picloram as auxin source, regardless of the donor plant material. The comparison of the results obtained with the single cross ‘SC 35’ which contains genes of Secale vavilovii and the true Secale cereale donor forms clearly show the genotypic influence of donor plant material on induction and regeneration ability. 相似文献
97.
98.
印度梨形孢对水稻的促生作用及其机理的初探 总被引:5,自引:0,他引:5
印度梨形孢(Piriformospora indica)是一种能与植物建立互惠共生关系的根部内生真菌,能促进植物生长,增加作物产量。为了研究印度梨形孢对水稻生长发育的影响,将印度梨形孢与籼稻苗共培养后,分析印度梨形孢对水稻植株高度、生物量、分蘖数、抽穗期、穗粒性状、叶绿素含量、硝酸还原酶活性、根系活力以及生长相关调控基因表达水平的影响。结果显示,接种印度梨形孢的水稻株高、地上部干鲜质量、分蘖数、硝酸还原酶活性和根系活力显著高于对照;与对照相比,印度梨形孢定殖的水稻植株抽穗期提前4~6d;印度梨形孢处理第3、4周后,叶片叶绿素含量比对照分别增加了19.77%和17.89%。RT-PCR分析表明,印度梨形孢定殖的水稻植株叶片中生长素相关调控基因OsIAA13和YUCCA的上调表达,表达量分别为对照的1.49倍和1.30倍;负调控水稻生长的NRR基因表达量为对照的58%。印度梨形孢促进水稻地上部的生长与叶绿素含量、硝酸还原酶活性、根系活力和生长相关调控基因的表达有关,印度梨形孢可能通过提高光合速率、增强水稻对矿质营养的吸收与利用和诱导生长素的分泌,促进水稻地上部的生长。 相似文献
99.
100.
大叶相思扦插繁殖技术研究 总被引:5,自引:0,他引:5
研究大叶相思激素种类、浓度、处理时间以及扦插基质对大叶相思插穗生根和早期生长的影响,分析大叶相思扦插生根随时间的变化趋势,并在此基础上利用隶属函数法对各处理的生根效果进行综合评价。结果表明:3种激素以IBA处理生根效果最好,在平均根数及最长根长方面显著优于其它2种激素,并得出以黄心土为基质,用IBA 200 mg/L处理2 h为大叶相思扦插的最佳组合。10月份扦插繁殖大叶相思,插后10 d开始生根,15~20 d为生根高峰期。 相似文献