Improvement of ovulation induction by additive injection of 17,20β‐Dihydroxy‐4‐pregnen‐3‐one after human chorionic gonadotropin administration in a pelagic egg spawning marine teleost,nibe croaker Nibea mitsukurii (Jordan & Snyder)

This study aimed to develop the consistent ovulation induction method in a pelagic egg spawning marine teleost, nibe croaker Nibea mitsukurii. Attempts to induce oocyte maturation and ovulation in nibe croaker using human chorionic gonadotropin (hCG; 0.5 IU g^?1) resulted in the normal progression of oocyte maturation and hydration, but a failure to induce ovulation in many individuals. This ovulation disorder was similarly observed even when the dose of hCG was increased 10 times (5 IU g^?1) or decreased to one tenth (0.05 IU g^?1), indicating that it cannot be completely overcome solely by hCG administration. However, this ovulation disorder could be completely overcome by subsequent administration of 17,20β‐dihydroxy‐4‐pregnen‐3‐one (DHP) at the appropriate dose (0.5 μg g^?1) and time (20 h after hCG administration). An increase in the number of individuals that ovulated due to DHP administration led to an increase in individuals producing larvae, resulting in an approximately threefold increase in the estimated number of larvae produced compared with the group of fish administered hCG alone. Thus, this ovulation induction method using DHP administration after hCG was demonstrated to overcome the ovulation disorder in nibe croaker and could be applicable to commercially important species with similar ovulation problems.     

ABT生根粉在农田林网造林上的应用试验

通过用 ABT生根粉处理杨大苗根系 ,进行农田林网造林 ,不但提高了造林成活率 ,而且对加快幼林高、径生长及根系的发育效果明显。并取得显著的经济效益。     

植物诱导抗性的研究进展

诱导抗性具有广谱性以及对环境安全的优点已成为植物病虫害防治的新手段,受到广泛的关注。综述了近年来国内外植物诱导抗性的研究进展,分析了一般特征、诱导抗性的诱导因子和机制等。     

不同防褐化措施对苏丹草愈伤诱导以及抗褐化的效果研究

苏丹草组织材料在组织培养过程中会产生酚类物质,影响愈伤组织的生长,甚至导致愈伤组织死亡。本试验以苏丹草幼穗为外植体,探讨了不同防褐化措施对苏丹草愈伤诱导的影响及抗褐化的效果防止。结果表明,活性炭、V_C、PVP和AgNO₃均能不同程度地提高愈伤诱导率和降低褐化率。其中,培养基中低浓度的蔗糖(10~20 g/L)能降低褐化率,但同时也降低了愈伤诱导率,而高浓度的蔗糖(40~50 g/L)能提高愈伤诱导率但同时也增加了褐化率。柠檬酸能提高愈伤诱导率但不能防止褐化。当活性炭的添加量为0.15 g/L时,愈伤的诱导及褐化防止效果最好。     

Emerging technologies for the chemical control of root parasitic weeds

Parasitic plants in the Orobanchaceae family include devastating weed species, such as Striga, Orobanche, and Phelipanche, which parasitize major crops, drastically reduces crop yields and cause economic losses of over a billion US dollars worldwide. Advances in basic research on molecular and cellular processes responsible for parasitic relationships has now achieved steady progress through advances in genome analysis, biochemical analysis and structural biology. On the basis of these advances it is now possible to develop chemicals that control parasitism and reduce agricultural damage. In this review we summarized the recent development of chemicals that can control each step of parasitism from strigolactone biosynthesis in host plants to haustorium formation.     

茄子愈伤组织诱导条件的初探

本文研究了3种不同诱导条件对茄子愈伤组织诱导的影响，结果表明：光照强度1000lx与9000lx对茄子愈伤组织诱导率无影响，但1000lx的光照强度下诱导所需时间长，且愈伤组织块致密，不易褐变。以茄子不同部位茎段作为外植体，结果是茎基部的茎段诱导率明显高于近芽部的诱导率。供试的几种苗龄中，55d苗龄的幼苗茎段的诱导率最高，而30d苗龄茎段的诱导率最低。     

抗菌肽V13KL原核表达载体的构建及其表达产物的鉴定

将V13KL编码基因片段克隆到原核表达载体pET30b（＋）,并在目的蛋白N端设计肠激酶酶切位点,构建出pET30b（＋）-VK13L重组质粒,转化大肠杆菌表达菌株BL21（DE3）,优化诱导条件,使得抗菌肽得到了高效表达。经Tricine-SDS-PAGE和Westernblotting鉴定,目的蛋白的相对分子质量与预期一致。结果表明,V13KL基因成功克隆并且获得表达,在诱导体系中加入1mmol／LIPTG诱导6h便可检测到蛋白表达。     

外源ABA浸种对冬油菜种子萌发及幼苗抗寒性的诱导效应

为探讨外源脱落酸（ABA ）对北方寒旱区冬油菜幼苗抗寒性的诱导效应,试验分别用不同浓度的ABA对超强抗寒性白菜型冬油菜品种“陇油6号”和弱抗寒性品种“天油2号”进行浸种处理,研究不同浓度ABA浸种对冬油菜种子萌发及常温和低温胁迫条件下相关抗寒指标的影响。结果表明,10～70 mg · L－1 ABA处理促进了种子萌发,80 mg·L－1ABA处理对发芽率和发芽势有抑制作用;30 mg·L－1浓度的ABA对冬油菜抗寒性诱导效果最佳,可显著（P＜0．05）提高冬油菜幼苗抗氧化酶（SOD、POD和CAT）活性,延缓叶绿素含量的降低,增加叶片脯氨酸含量,减缓膜脂过氧化产物丙二醛的积累;外源ABA处理在品种上存在差异,对抗寒性强的品种陇油6号效果明显。     

同树种引诱成虫集中产卵法防治杨树云斑天牛

经过近10 a试验,研究出了一种高效防治杨树云斑天牛的新技术——“配置杨树易感品种引诱成虫集中产卵法”.即在造林时按照一定比例配置具有一定速生性但易感云斑天牛危害的杨树品种作为引诱种,引诱云斑天牛成虫在引诱种上集中产卵,而后只需对占总林分极小比例的引诱种进行涂刻槽和插毒签防治即可.这种技术将营林措施和化学物理措施结合起来,防治效果达到95％以上,防治费用降低50％,同时该技术具有技术简单、易掌握等优点,适合在营建杨树丰产林时推广应用.     

铁冬青芽诱导和增殖的试验初探

以3a生铁冬青茎段为外植体,探讨不同培养基对铁冬青芽诱导和增殖效果。结果表明:铁冬青采用MS+6-BA1 ml/L+IAA0.2 ml/L诱导,增殖培养基采用1/2MS+6-BA1.5 ml/L+IAA0.5 ml/L,增殖系数为3.3。