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101.
板栗产生空苞是一个全国性的问题,如何降低空苞率是很多学者研究的课题,本文从缺硼是引起板栗空苞的主要原因入手,选定具有代表性的地块,以不同的施硼量对降低空苞率,增加产量等因素进行分析研究,分析施硼的必要性,确定最佳施硼量,以指导生产实践,结果表明,施硼对降低板栗空苞率,增加产量有明显效果,且肥效能持续3-5年,板栗施硼时以每平方米树冠投影施入15克为最佳施硼量,增产幅度达45.7%,空苞率降低29.1%。 相似文献
102.
In this presentation,we report on de novo and axillary shoot regeneration and rooting of shoots maintained over a long term,from cultures of Tectona grandis L.Shoot-tips of teak shoots forced from epicormic buds were used as the starting material for axenic shoot-culture establishment.Long term maintenance of such axenic shoot cultures was carried out by regular sub-culturing on MS media supplemented with N 6-benzyleadenine (BA,8.8 μmol L-1) and indole-3-butyric acid (IBA,2 μmol L-1) for 24 months.Vigorously growing shoot tips (2 3 cm long) were inoculated on the MS basal medium supplemented with different concentrations (0,1,2,4,6,8 or 10 μmol L-1) of either IBA or α-naphthaleneacetic acid (NAA) for rooting.Axillary and de novo shoots were developed from axillary and cut basal ends of shoots,respectively.Shoots growing on auxins were further sub-cultured (every 15 days) and maintained for 45 days.The greatest number of de novo (5.06) as well as axillary shoots (2.85) was observed on the MS medium supplemented with 10 μmol L-1 NAA or 8 μmol L-1 IBA,respectively,after 45 days.The combinations of both IBA (μmol L-1) + NAA (μmol L-1) were tested at different concentrations (4 + 4,6 + 6,8 + 8) supplemented to a half strength MS basal medium with 0.1% activated charcoal for rooting of decapitated and non-decapitated de novo and axillary shoots.Rooting from non-decapitated de novo shoots was highest (93.33%) with a mean number of roots of 4.61 on this medium,supplemented with 6 μmol L-1 IBA + 6 μmol L-1 NAA,after 36 days of initial culture.Individual auxin,however,was not effective for root induction.Rooted shoots were acclimatized in a green house and after four weeks plantlets were transferred to the field. 相似文献
103.
不同植物生长调节剂对黄秋葵组织培养的影响 总被引:1,自引:0,他引:1
以黄秋葵无菌实生苗的带一叶一芽的茎段为外植体,研究了不同植物生长调节剂处理对丛生芽诱导和不定芽生根的影响。结果表明:当外植体接种于1/2MS基本培养基中,一定的浓度范围内,IAA浓度的增加显著促进了黄秋葵茎段的分化率和增殖率,而6-BA的存在提高了IAA的这种促进作用,但并不明显,最优组合为IAA 1.0mg/L+6-BA 2.0mg/L。待丛生芽生长到1cm以上,切出单个不定芽,接入添加不同NAA浓度的1/4MS基本培养基中,发现生根率和生长状况在NAA 0.1mg/L时表现最好。 相似文献
104.
105.
以红掌愈伤组织为材料,研究影响红掌愈伤组织增殖和分化以及芽增殖的因素。结果表明:以MS+6-BA1.0 mg/L+KT 0.3 mg/L+蔗糖30 g/L+琼脂8 g/L为红掌愈伤组织增殖和分化的最佳培养基,培养到8周绝对生长速度达到910.31%、分化率达到100%,到150 d时分化指数达到24.17;在芽增殖培养试验中,以1/2 MS+6-BA2.0 mg/L+NAA 0.5 mg/L+KT 0.1 mg/L+蔗糖30 g/L+琼脂8 g/L为适宜培养基。在培养方式上,液体培养优于固体培养。 相似文献
106.
三种玉簪新品种离体快繁技术的研究 总被引:3,自引:0,他引:3
以3种玉簪"金头饰"(H.‘Gloden Tiaia’)、"小黄金叶"(H.‘Gloden Cadet’)和"金鹰"(H.‘Gloden Eagle’)的幼嫩花蕾为外植体诱导不定芽,成功的建立了3个品种的离体快繁体系。结果表明:不定芽诱导最佳培养基为MS+6-BA 2.5mg/L+NAA 0.2mg/L;在增殖培养基中,"金头饰"最佳增殖培养基为MS+6-BA 2.0mg/L+NAA 0.5mg/L;"小黄金叶"最佳增殖培养基为MS+6-BA 1.0mg/L+NAA 0.2mg/L;"金鹰"最佳增殖培养基MS+6-BA 4.0mg/L+NAA0.2mg/L;无生长调节剂的MS为"金鹰"的最佳生根培养基,生根率达100%以上;"小黄金叶"在培养基MS+NAA 0.5mg/L中生根率达到100%以上;"金头饰"在培养基MS+NAA 0.3mg/L中生根率也达到100%以上。其移栽成活率均为100%。 相似文献
107.
兴仁金线莲丛生芽诱导增殖研究 总被引:2,自引:1,他引:1
[目的]筛选兴仁金线莲丛生芽的诱导和增殖的最佳培养基。[方法]用野生兴仁金线莲植株茎段作外植体,以MS为基本培养基,并添加不同浓度的6-BA和NAA,诱导丛生芽,筛选最佳培养基配方。[结果]MS是兴仁金线莲快繁最佳基本培养基;2.0~3.0 mg/L的6-BA有利于丛生芽的诱导;1.0 mg/L 6-BA+0.1 mg/L NAA有利于芽的生长;最佳蔗糖浓度为25 g/L。[结论]MS+2 mg/L 6-BA+0.2 mg/L NAA+25 g/L蔗糖为丛生芽增殖的最佳培养基配方。 相似文献
108.
109.
红哺鸡竹丛生芽诱导的初步研究 总被引:2,自引:0,他引:2
以红哺鸡竹为材料,以MS为基本培养基,通过对外植体不同的消毒方法和防褐变处理,附加不同种类和浓度的植物生长调节物质诱导丛生芽。结果表明:红哺鸡竹带芽节段最佳消毒方式是75%酒精浸泡30s,用0.1%升汞处理6min。红哺鸡竹丛生芽诱导的最佳培养基是:MS+6-BA(5mg/L)+TDZ(0.1mg/L)。在培养基中加入PVP(1g/L)有明显的防褐变效果,外植体在半胱氨酸(100mg/L)溶液浸泡30min以及暗培养能有效降低褐化率。 相似文献
110.
Techniques for the production of raspberry long canes with high yield potential were studied on a research station and in two commercial nurseries in South Norway. Potted ‘Glen Ample’ plants were grown in the open and in polyethylene greenhouses during two seasons in order to optimize cultural practices. Dates of propagation and transfer to the production sites were varied. Following cold storage from December to early June, the canes were tipped (cut) at 160 cm height and grown in open plastic tunnels in the fruiting season for the evaluation of growth and yield performance. Remarkable berry yields of 1.5–3.8 kg per plant (cane) were regularly achieved. When grown in the open, later starts than June 1 (June 15 and July 1) successively reduced yields. On the other hand, an earlier start involves risks of growth cessation due to low spring temperature. When grown in greenhouses, high yields were still possible when plants were transferred from propagation conditions as late as July 1, although optimal yields of nearly 4 kg per plant were obtained with transfer on June 15. In a year with unusually high summer temperatures, the yields of canes produced in the open and in greenhouses did not vary significantly, whereas in the second year with normal summer temperatures, canes produced in greenhouses consistently out-yielded those produced in the open by about 1 kg per cane. Regression analyses revealed that high yields were associated with fruiting cane architecture traits such as cane height, number and length of laterals, and a low proportion of dormant buds. The single most important component was lateral length which alone accounted for 82% of the yield variation. Since lateral lengths increased from the shoot tip towards the base, cane heights in excess of 2 m are required for the attainment of top yields as the uppermost nodes with short and low-yielding laterals then can be eliminated by tipping. 相似文献