Cytological and genetical studies on male sterility inCryptomeria japonica D. Don

Genetic male sterility is a useful trait in plant breeding, especially in angiosperm crops such as corn, onion and carrot. We found a male sterile sugi (Cryptomeria japonica D. Don) tree in Toyama, Japan. Pollen of sugi is one of the major causes of pollinosis in Japan. We carried out this research in an attempt to make clear the characteristics and inheritance of this male sterility. Microsporogenesis of the male sterile tree proceeded meiosis, however, the microspores collapsed after they were separated from pollen tetrads in locules, resulting in complete male sterility. Most likely, ethylene evolution was responsible for male sterility expression. Full seed setting in the male sterile tree indicated normal macrosporogenesis. Seeds obtained from crossing between male sterile and normal lines showed relatively high level of germination and their seedlings grew vigorously. The somatic chromosome numbers of 241 germinated seeds, derived from the male sterile tree, were mostly 22, euploid. These results indicated that male sterile tree was different from other similar previously reported trees with low pollen fertility, resulting from triploid or trisomics. Probably, male sterility in sugi is either nuclear genetic male sterility or cytoplasmic male sterility. The study was partially supported by Program for Promotion of Basic Research Actives for Innovative Biosciences.     

NAA和IBA对菊花生长发育和花期的影响

通过对３个秋菊品种用长日照、ＮＡＡ、ＮＡＡ＋ＩＢＡ组合和自然短日照处理试验,发现长日照处理是秋冬季菊花栽培延迟开花提高品质的最佳途径．ＮＡＡ和ＮＡＡ＋ＩＢＡ组合喷施叶面,可显著延迟秋菊开花,随浓度的提高,延迟开花时间越长．不同的品种株高、叶数、开花直径对生长调节剂反应不一样,短日照迟感型品种使用ＮＡＡ或ＮＡＡ＋ＩＢＡ组合处理比短日照敏感型品种在生长质量与延迟开花方面可获得更好的效果．ＮＡＡ＋ＩＢＡ组合处理效果比ＮＡＡ单独喷施效果好．     

香软米滇屯502的选育

 主要介绍了利用云南高杆大穗米质特优的毫皮作母本与省协作组选育的株型紧凑、抗性强的香糯米滇侨20杂交,选育出高产优质抗病香软米新品种——滇屯502,同时系统地介绍了软米、香米、香软米的选育,供育种单位参考.     

Synthesis and Evaluation of New Ethyl 2,3- Dihydro-3-oxoisothiazolo[5,4-b]pyridine- 2-alkanoate Derivatives as Potential Herbicides

Several ethyl 2,3-dihydro-3-oxoisothiazolo[5,4-b]pyridine-2-alkanoate derivatives were synthesized as herbicides. Only 5-methyl derivatives inhibited both hypocotyl and root growth in the lettuce (Lactuca sativa L.) seedling test at 100 mg litre^-1. Only ethyl propionate and valerate derivatives showed significant inhibition at 0·1 mg litre^-1, whereas ethyl acetate or butyrate derivatives were inactive. Contrary to unoxidized derivatives, the inhibitory effect of 1-oxide and 1,1-dioxide derivatives was strongly dependent on concentration; ethyl 2,3-dihydro-5-methyl-3-oxoisothiazolo[5,4-b]pyridine-2-propionate 1,1-dioxide inhibited 100% of germination at 100 mg litre^-1 and 45% of lettuce seedling growth at 0·1 mg litre^-1. Quantitative structure–inhibition of growth relationship analysis carried out by adaptive least-squares (ALS) method gave a good correlation with small and hydrophobic 5-substituents as well as with odd carbon-chain ethyl alkanoates in position 2. Active compounds did not show auxin-like activity from 0·1 to 100 mg litre^-1. © 1997 SCI.     

坡面径流泥沙计算中需解决的认识问题

基于土壤侵蚀规律的研究特点，特别是坡面水蚀动力过程的研究需要，对以往传统的坡面径流泥沙计算方法进行的分析发现，传统的计算方法误将土壤中的孔隙水当作坡面径流，从而导致误将坡面的侵蚀对象及搬运物当作坡面的侵蚀动力，为进一步分析坡面水蚀动力机制带来了困难。在上述分析基础之上，提出了坡面径流泥沙的计算方法，并与传统方法进行了计算误差分析。结果表明，两种方法的计算误差随含沙量的增加而增大。当土壤容重为１．２ｔ／ｍ３时，若含沙量达３００ｋｇ／ｍ３，径流量计算误差大于２０％，含沙量计算误差接近２０％。     

罗汉松抗白蚁成份的提取及生物测定

现在人们越来越多地使用生物杀虫剂来防治白蚁。对罗汉松中的抗白蚁生物活性成份进行了提取和生物测定。结果表明．利用乙醇、乙醚、丙酮及水等溶剂对罗汉松木粉进行提取及分离后得到了两组化学组分(E6．E7)．它们对家白蚁都有较好的毒害作用．14d内对白蚁的致死率分别为100％和90．3％。     

高效液相色谱法同时测定遍山红中8种化学成分含量

【目的】建立高效液相色谱法(HPLC)测定遍山红中没食子酸、二氢杨梅素、原儿茶酸、芦丁、杨梅苷、齐墩果酸、槲皮素、山柰酚化学成分含量的方法,以期更好地控制遍山红的药材质量,为其药用开发提供科学依据。【方法】采用ZORBAX SB-C18色谱柱、乙腈-0.2%磷酸为流动相、流速0.6 mL/min、柱温28℃的HPLC测定广西都安县4个采集点(弄苍队、卜凡队、弄外队、百外队)遍山红中8种化学成分的含量。【结果】260 nm是测定混合对照品溶液和遍山红供试液中8种化学成分的最大波长。4个采集点遍山红中8种化学成分的含量范围:没食子酸1.53~1.75 mg/g、原儿茶酸1.11~1.28 mg/g、二氢杨梅素0.99~1.44 mg/g、芦丁0.34~0.42 mg/g、杨梅苷1.58~1.83 mg/g、齐墩果酸0.63~0.77 mg/g、槲皮素1.03~1.11 mg/g、山柰酚0.65~0.69 mg/g。8种化学成分质量浓度与峰面积线性关系及色谱峰分离效果均良好(r>0.9990);没食子酸、原儿茶酸、二氢杨梅素、芦丁、杨梅苷、齐墩果酸、槲皮素和山柰酚的进样量范围分别为7.20~43.20、3.36~20.16、5.92~35.52、1.60~9.60、6.40~38.40、3.68~22.08、3.20~19.20和3.52~21.12μg/mL,对应的平均加样回收率为101.72%、96.49%、97.04%、99.79%、99.80%、99.44%、101.52%和96.63%。【结论】建立的HPLC具有操作简便、准确可靠、灵敏度高、重现性好等优点,可用于遍山红的质量控制。     

三叶香茶菜扦插繁殖试验

以三叶香茶菜[Rabdosia ternifolia(D.Don)Hara]当年生植株不同部位的枝条作为试验材料,通过不同浓度的生长激素IBA和NAA处理,考察IBA和NAA浓度及不同的扦插时间对其扦插生根的影响。结果表明,200 mg/L的IBA和NAA组合处理效果均优于其他浓度处理,经方差分析可知,各处理间生根率存在明显的差异,以IBA处理影响最大,对根长和发根数的影响不显著,但可明显促进其增加。试验显示,在5月份扦插,200 mg/L IBA+200 mg/L NAA浸泡12 h处理的三叶香茶菜枝条生根效果最好,生根率高达75.8%。     

樱桃结果母枝直径与开花习性的相关性分析

为了探讨影响樱桃[Cerasus pseudocerasus(Lindl.)G.Don]开花习性的内在因素及机理,研究了樱桃结果母枝直径与开花习性的相关性。结果表明,樱桃结果母枝直径与结果母枝长度和总芽量之间呈高度正相关,与叶芽量、4朵花芽量和4朵花量之间呈显著正相关,与萌芽率、3朵花芽量和3朵花量之间呈显著负相关,与2朵花芽量、总花芽量和2朵花量之间呈低度负相关,与总花量呈负相关。作图分析结果表明,樱桃结果母枝直径以4.4~6.5 mm最好,其次以6.5~7.3 mm较好;回归分析结果表明,樱桃结果母枝直径与结果母枝长度、总芽量、叶芽量、萌芽率、2朵花芽量、3朵花芽量、4朵花芽量、总花芽量和总花量等指标的回归曲线都符合二次回归方程。建议可以通过培养优质枝梢来提高花的质量,通过调查樱桃结果母枝直径来预测各类花芽量和开花量等指标。