除花蕾对紫胶虫种胶产量和质量的影响

紫胶虫寄主以灌木生长较快投产较早。但大多数灌木寄主的开花结实率较高,花果期较长,消耗大量的无机元素,直接和间接地影响着寄主植物营养器官中碳水化合物、氨基酸等有机物质的合成与运输,从而影响到紫胶虫的生长发育和泌胶状况,且常常导致寄主树本身的生势下降,过早出现衰老,缩短使用寿命。本研究结果表明:应用乙烯利(0.3％)和尿素(2％)的混合水溶液喷洒花蕾,可抑制开花结实,刺激萌芽更新,增多侧枝,从而可提高冬代种胶的产量和质量,缩短寄主轮歇期。人工剪除花蕾,也有利于种胶产量和质量的提高。     

Storage lipid dynamics in somatic embryos of Norway spruce (Picea abies): histochemical and quantitative analyses

Adequate storage compounds are a prerequisite for successful development during the later stages of somatic embryogenesis; however, the critical amount of reserves below which somatic embryos fail to mature and germinate has not been determined. We analyzed storage lipids during Norway spruce (Picea abies (L.) Karst.) somatic embryogenesis. As maturation progressed, lipids, which were stored as lipid bodies in the cytoplasm, were localized first in suspensor cells of the early embryos, and later in the embryonic root pole, superficial layers of the hypocotyl and in cotyledons. The concentration of total lipids exhibited marked variation, with values peaking during cotyledon development and then decreasing during maturation. Linoleic (18:2), oleic (18:1), palmitic (16:0) and 5,9-octadecenic (5,9-18:2) acids were the most abundant fatty acids in embryos. As embryos developed, linoleic acid concentration increased slightly, whereas oleic acid concentration decreased. Oleic acid was the most prominent component of the fatty acid spectrum in isolated dormant zygotic embryos and megagametophytes. Addition of 5% polyethylene glycol to the medium during somatic embryo maturation caused a shift in the fatty acid spectrum toward that of zygotic embryos. During maturation, changes in the exogenous carbohydrate supply had no significant effect on total lipid concentration in mature embryos. A marked decrease in lipid concentration was detected during desiccation, indicating the importance of adequate lipid reserves during this developmental stage. The lipid content of zygotic embryos differed considerably with harvest year and location, suggesting that zygotic embryo data cannot be an indicator of somatic embryo quality.     

紫胶丰产优质的肥药试验

对以３年生南岭黄檀为寄主的紫胶虫的幼虫期和成虫期进行喷施肥药试验。结果表明：适时合理的喷施、管理能提高紫胶的一、二级比例和放收比;幼虫期管理的最佳组合为紫胶虫固定后１０ｄ对寄主树根部每株施尿素２００ｇ、过磷酸钙５００ｇ,对固虫过多的细枝进行抹虫,并对树冠喷２．５％的稀土液;成虫期管理的最佳组合是紫胶虫涌散前６０ｄ施尿素２００ｇ／株,在树冠上喷１％Ｋ２ＰＯ４和４０×１０－６赤霉酸。     

漂白胶贮存性质的研究(一报)——漂白胶脱氯反应的研究

本文通过测定脱氯程度不同的漂白胶样品的结合氯含量、热寿命、软化点和颜色,研究了漂白胶脱氯反应的性质,结合氯含量与热寿命的关系以及软化点和颜色的变化规律。发现漂白胶的脱氯反应是一级反应,分为两段,前一段的反应常数为后一段的四倍,说明一部分氯容易脱除,而另一部分则比较难,后者留在漂白胶中对贮存性影响不大。此研究结果为解决漂白胶贮存性差这一难题提供了理论依据和基本途径。通过测定一批样品在多年存放期间热寿命的变化,证实了本研究结论的正确性。     

火炬松胚性愈伤组织诱导和植株再生的研究

火炬松胚性愈伤组织诱导和植株再生的研究唐巍欧阳藩（中国科学院化工冶金研究所生化工程国家重点实验室北京１０００８０）郭仲琛（中国科学院植物研究所北京１０００９３关键词火炬松,体细胞胚胎发生,植株再生本文于１９９６年１０月２８日收到。国家“８６３”资...     

Defence reactions of developing somatic embryos of Algerian fir (Abies numidica)

Defence reactions of embryonal suspensor mass (ESM), precotyledonary, cotyledonary and desiccated cotyledonary somatic embryos of Abies numidica were tested by dual cultures with Phaeolus schweinitzii. Defence reactions were expressed at a very early stage of somatic embryo development. Both ESM and early somatic embryos inhibited mycelial growth, but the strongest defence was shown by the precotyledonary somatic embryos. The cotyledonary and desiccated cotyledonary embryos also showed defence reactions but with less intensity. Eight major components of soluble proteins, already present in the ESM, increased in concentration during subsequent developmental stages. Synthesis of two low‐molecular components of 6 and 3 kDa appeared in desiccated embryos. Probable regulation of defence reactions by auxins in early somatic embryos, as well as by abscisic acid content and storage proteins in subsequent developmental stages, is discussed.     

Reduction in egg hatch ofArgas (Argas) reflexus (Fab.) (Acari,Argasidae) due to colchicine

The eggs ofArgas (Argas) reflexus (Fab.) were exposed to 0.05% colchicine on 9th, 15th or 23rd–25th days of embryonic development at 25°C and 30% RH. The eggs on the 15th and 23rd–25th days of development were the most sensitive to colchicine. In these experiments 6.9% and 9.4% embryos died, respectively. The largest number of disturbances of egg hatch (11.5%) were observed after exposure of the eggs to colchicine on 23rd–25th days of embryogenesis.     

饲料型四倍体刺槐幼胚离体培养挽救技术研究

遗传变异丰富、具有重要遗传育种价值的饲料型四倍体刺槐幼胚自然败育率很高,研究其离体培养挽救技术具有重要的遗传育种学意义。以处于不同发育时期的饲料型四倍体刺槐幼胚为材料,进行了其离体培养促萌试验,试验结果表明:胚珠的适宜离体培养时期为花后30 d,萌动率47.7%;胚珠的适宜萌动培养基为Nitsch 6-BA 0.5 mg/L IBA 2 mg/L GA30.5 mg/L;筛选出的最佳愈伤组织诱导培养基上得到的愈伤组织诱导率为38.6%,并初步诱导出了不定芽;愈伤组织切片表明,饲料型四倍体刺槐幼胚愈伤组织的增殖生长以内起源为主。     

第二代杉木人工林生物量的时空特征

探讨了第二代杉木人工林生物量的时空特征，运用Richards模型对杉木人工林生物量动态模拟，结果为：W=272.745（1-e^-0.126（t-1））^1/1-0.559，杉木人工林生长过程可分成4个阶段：0～5a幼林成长阶段；5～8a干材速生阶段；8～25a为成热阶段；25a后为过熟阶段。其采伐年限为25a，密度为2475株／hm^2的杉木可获得最大生物量272．745株／hm^2。