板栗雌花分化相关影响因素研究进展

板栗雌花数量少是其高产的主要限制因子之一,本文概述了近年来我国在板栗雌花分化的主要影响因素中的品种、树龄、密度、C/N、N、P、K营养及植物生长调节剂、整形修剪等方面的研究进展,并提出了选育优良板栗品种,辅以相应管理技术,实现板栗高产高效栽培的建议。     

胎里红柿早期丰产栽培技术

胎里红柿早期丰产栽培技术要点为，施足基肥，大穴栽植；科学施用肥、水，冬、夏剪相结合，调控营养生长与生殖生长；使用生长调节剂及各种农业技术措施促花和提高坐果率，科学防治病虫害等。     

梨枣组织培养的研究

从梨刺茎段培养直接诱导了不定芽,并形成了完整的试管苗。试验表明,在MS+ZT1.75mg·L-1+KT2.0mg·L-1培养基中,梨枣茎段可以分化不定芽,低含量的NAA和AgNO3可以促进不定芽的形成。在MS+ZT1.75mg·L-1+KT2.0mg·L-1+NAA0.05mg·L-1+AgNO32.0mg·L-1培养基中,芽的增殖系数最高,达到2.25倍。在1/2MS+IBA0.08mg·L-1培养基上,试管苗的生根率达到95.0%。     

余甘子丛生芽诱导和快速繁殖研究

本试验以余甘子嫩芽和嫩枝茎段为外植体 ,在 MS培养基中进行离体繁殖和培养试验。结果表明 ,添加细胞分裂素 BA对丛生芽诱导有明显促进作用 ,激素组合以 BA与 NAA为最好 ,嫩芽外植体诱导丛生芽的最适培养基为 MS BA0 .5 mg/ L NAA 0 .1mg/ L,分化率达 90 %以上 ;嫩枝茎段旅导丛生芽所需的 BA浓度相对高些 ,最适培养基为 MS BA 2 .0 mg/ L NAA 0 .1mg/ L,分化率达 5 6 .7% ,丛生芽增殖生长培养基为 MS BA 0 .1mg/ L NAA 0 .1mg/ L Na H2 PO45 0 mg/ L。生根培养基为 1/ 2MS NAA 0 .2 5 mg/ L IBA 0 .2 5 mg/ L ,生根率在 30 %左右     

板栗花器分化发育期气候因子对其产量形成的影响

利用淳安县１９７３～１９９２年板栗产量和相应的气象资料，就板栗花器分化期一系列气象因子变他对其产量形成的作用显著性及其丰歉年景作用权重作分析研究。结果表明，４月和５月日照时数、越冬极端最低温度、５～６月降水量是影响气象产量的关键因子，此４因素对气象产量的作用权重占年总气象产量的７５．５５％～９４．４５％，在此基用上进一步提出了该县板栗产量模式及丰产建议。     

Configuration and development of root systems of cuttings and seedlings of Eucalyptus globulus

Stem cuttings of Eucalyptus globulus are used within tree improvement programs and for mass deployment. To be successful, cuttings must perform as well or better than seedlings. The root systems of cuttings are fundamentally different from those of seedlings. If these differences influence growth, the differences and their consequences must be identified and the propagation system manipulated to improve performance of the propagules.Cuttings are only a viable alternative to seedlings as planting stock if the method of propagation does not affect their growth and development adversely. Full-sibling cuttings and seedlings of Eucalyptus globulus were compared under controlled environmental conditions to minimise extraneous sources of variation, and to establish whether changes in growth or development were induced by propagation. On three occasions over a period of eight weeks root-collar diameter, shoot height, leaf and stem weight, shoot/root ratios and root system morphology were measured on cuttings and seedlings. Seedlings were taller than cuttings throughout the experiment, but both plant types had similar height growth rates. Diameter growth rates were lower in cuttings than seedlings, and there were differences in both height and diameter growth rates between families. Root system configuration differed between the plant types. Seedlings had strongly gravitropic tap-roots, with two types of primary roots from which secondary roots emerged. Cuttings had no tap roots, and the main structural components of their root systems were adventitious roots formed during propagation. Cuttings did not develop further structural roots during the experiment, whereas seedlings continued to develop primary roots. Individual primary roots of cuttings were longer and had larger mid-point diameters than those of seedlings, but the total length of primary roots was greater in seedlings. Seedlings also had a greater number and total length of secondary roots. Shoot/root ratios, calculated from a range of functional measures, were higher in cuttings than seedlings.     

松毛虫发生世代与世代分化

本文论述松毛虫发生世代和世代分化的复杂性,包括落叶松毛虫、马尾松毛虫、赤松毛虫和油松毛虫等。发生世代因地区不同而异。在同一地区,由于松毛虫幼虫的滞育,常出现世代分化。世代分化比例在不同地区、不同年份、不同松林和不同树木之间都有差异。在同一地方,不同年份也有差异。滞育与幼虫孵化期、气候、生态条件和食料有关。本文还讨论了“油松毛虫发育起点温度和有效积温的研究”〔林业科学,1987,23(3)〕的有关问题。     

优良保健树大叶冬青组培扩繁的研究

以大叶冬青具节茎段芽体增殖产生试管苗,适宜培养基为MS 1．Oμmol NAA 8．8μmol BA或MS 1．0μmol NAA 9．1μmolZT;幼叶外植体诱导的愈伤组织块转培于WPM 5．Oμmol TDZ 3.Oμmol IAA培养基上,能产生较多不定芽苗(每一愈伤组织块平均产生11．2株);BA对大叶冬青外植体不定芽的处理能产生较好的增殖系数与高生长;试管苗适宜生根处理为：1／4KS 1．Oμmol NAA(或 1．Oμmol IBA);室外移栽成活率达90％。     

改进马尾松育苗方法的试验

对马尾松采用控制苗木密度、芽苗截根移栽和接种菌根菌等技术进行育苗试验，结果表明：苗木密度应控制在１５０株／ｍ２，芽苗截根以保留主根长度１／２为宜；采用厚环乳牛肝菌进行人工接种效果较好。     

昆明市西山区苹果的开花生物学特性与果实品质

对昆明市西山区大河果园主要苹果品种的开花生物学与果实品质进行调查研究,结果表明:花芽能顺利完成分化,乔纳金花芽分化要比红富士早,红富士的花芽坏死率为6.3%;各品种花期不一致,持续时间较长,约为20 d;各品种的果个不大,金冠果形指数为0.91~0.94、红富士为0.83~0.84;金冠苹果7月底时其成熟度和糖酸比都较低,应适当推迟采收期,红富士品种的成熟度和糖酸比在9月底达到较好的水平,可根据需要适时采收。