森林植物对大气二氧化碳浓度增高的生理生态响应(综述)

RECENTSTUDIESONPHYSIO-ECOLOGICALRESPONSEOFFORESTTREESTOELEVATEDATMOSPHERICCARBONDIOXIDEZhaoPing（SouthChinaInstituteofBotany,AcademiaSinica,Guangzhou510650）1问题的产生大气变化是目前生态领域中的热门话题,而对世纪中期大气中CO。浓度的升高及由此引发的温室效应对人类及生物赖以生存的环境和生态系统的影响已引起各国政府、科技界及公众的强烈关注。如何保护全球生态平衡使人类既满足经济发展的需要,又能促进环境、经济与社会的协同发展,已成为现代生态学研究的中心内容。尽管目…     

THE INFLUENCE OF LIGHT AND CARBON DIOXIDE ON PHOTOSYNTHESIS

1. An optical system is described which furnishes an intensity of 282,000 meter candles at the bottom of a Warburg manometric vessel. With such a high intensity available it was possible to measure the rate of photosynthesis of single fronds of Cabomba caroliniana over a large range of intensities and CO₂ concentrations. 2. The data obtained are described with high precision by the equation KI = p/(p ² _max. – p ²)^½ where p is the rate of photosynthesis at light intensity I, K is a constant which locates the curve on the I axis, and p _max. is the asymptotic maximum rate of photosynthesis. With CO₂ concentration substituted for I, this equation describes the data of photosynthesis for Cabomba, as a function of CO₂ concentration. 3. The above equation also describes the data obtained by other investigators for photosynthesis as a function of intensity, and of CO₂ concentration where external diffusion rate is not the limiting factor. This shows that for different species of green plants there is a fundamental similarity in kinetic properties and therefore probably in chemical mechanism. 4. A derivation of the above equation can be made in terms of half-order photochemical and Blackman reactions, with intensity and CO₂ concentration entering as the first power, or if both sides of the equation are squared, the photochemical and Blackman reactions are first order and intensity and CO₂ enter as the square. The presence of fractional exponents or intensity as the square suggests a complex reaction mechanism involving more than one photochemical reaction. This is consistent with the requirement of 4 quanta for the reduction of a CO₂ molecule.     

黑曲霉几丁质和壳聚糖的研究

通过正交试验确定黑曲霉的最佳培养条件。由培养的黑曲霉湿菌体制备几丁质,最经济的方法是电解法;制备壳聚糖则采用间歇提取法,所得干燥壳聚糖产品的壳聚糖含量为９２．２９％,游离氨基为９６．１１％,１％壳聚精的１％醋酸溶液运动粘度为５．３３ｘ１０^－６ｍ^２／ｓ,粘均分子是为８．０２４ｘ１０^４,灰分为９．２４％,产品得率为９．７２％,探讨了从柠檬酸厂废弃酸渣中分离黑曲霉菌丝体的方法,得率为３０％左右。     

THE INFLUENCE OF CARBON DIOXIDE ON THE TOXICITY OF UN-IONIZED AMMONIA TO RAINBOW TROUT (SALMO GAIRDNERII RICHARDSON)

The toxicity of solutions of ammonia to fish in different dilution waters showed a variation which was not entirely related to the concentration of the un-ionized ammonia molecule. Evidence is presented which shows that this variation can be attributed to the increase in the concentration of free carbon dioxide at the gill surface, which causes a decrease in both the pH value and the concentration of unionized ammonia present; the extent of the decrease depends on the initial concentration of free carbon dioxide in the bulk of the solution. Quantitative measurements of the relation between the free carbon dioxide concentration of the water and the toxicity of un-ionized ammonia are correlated with a theoretical estimation of the pH value of the water at the gill surface.     

黑曲霉A3木聚糖酶酶学性质研究

黑曲霉A3(AspergillusnigerA3)的固体培养物浸出液,经过多步分离纯化后,获得三个组份的木聚糖酶,称为xⅠ、xⅡ和xⅢ.经7%凝胶浓度的盘状电泳分析均为单一组份.经等电聚焦电泳测xⅠ、xⅡ和xⅢ的等电点分别为6.8、5.5和6.1.SDS-PAGE测得亚基分子量(Da)分别为xⅠ,42000;xⅡ,20000;xⅢ,31000.三个酶组份的最适反应温度分别为xⅠ,40℃;xⅡ,50℃;xⅢ,50℃.最适反应pHxⅠ,3.5;xⅡ,4.5;xⅢ,5.0.保温一个小时后,酶的半失活温度分别为xⅠ,55.6℃;xⅡ,54.8℃;xⅢ,46.6℃.金属离子Ag+、Hg2+、Ni2+和脲对不同的酶组份具有一定的影响.     

黑曲霉A3木聚糖酶酶学性质研究*

黑曲霉A3（AspergillusnigerA3）的固体培养物浸出液,经过多步分离纯化后,获得三个组份的木聚糖酶,称为xⅠ、xⅡ和xⅢ。经7％凝胶浓度的盘状电泳分析均为单一组份。经等电聚焦电泳测xⅠ、xⅡ和xⅢ的等电点分别为6.8、5．5和6.1。SDS－PAGE测得亚基分子量（Da）分别为xⅠ,42000;xⅡ,20000;xⅢ,3000。三个酶组份的最适反应温度分别为xⅠ,40℃i;xⅡ,50℃;xⅢ,50℃。最适反应pHxⅠ,3．5;xⅢ,4．5;xⅢ,5．0。保温一个小时后,酶的半失活温度分别为xⅠ,55.6℃;xⅡ,54.8℃;xⅢ,46.6℃。金属离子Ag+、Hg2+、Ni2+和脲对不同的酶组份具有一定的影响。     

微量元素对虫草蝠蛾幼虫生长发育的影响

按月采样,分析测定虫草蝠蛾幼虫体微量元素的组成。应用Q模式系统聚类方法,分析了幼虫受环境影响引起的元素代谢变化。结果表明虫体所含元素与环境温度的变化及自身的生理活动密切相关。5、10月份幼虫组的元素含量相近,前者正当幼虫结束休眠后恢复活动的时期,后者是幼虫处于准备进入越冬的前期,两组幼虫此时均处于取食高峰期。3、4月份组的亦较接近,幼虫正渐恢复活动但不取食。8月份幼虫蜕皮前后,消耗较大,需摄取大量食物。计算结果表明7、9月份的元素含量接近,这与上述现象有一定联系;应用对应因子分析法得到的结果是:元素Fe、P对10、11月份幼虫组的贡献值显著;Na、Ca、Mg对8、9月份的贡献值显著;Cu、Zn、Co、Cd、Si对4、5月份的贡献值显著。     

THE EFFECTS OF ULTRAVIOLET RADIATION ON SPORES OF THE FUNGUS ASPERGILLUS NIGER

The survival ratio of Aspergillus spores exposed to ultraviolet radiation has been measured as a function of total incident energy for wave lengths of 2537 Å, 3022 Å, 3129 Å, and 3650 Å. The effect of humidity on killing of Aspergillus spores by ultraviolet radiation has been found to be negligible. A delay in germination as a result of irradiation has been found. The Bunsen-Roscoe reciprocity law has been found to hold within the limits of the radiation intensities studied. Certain morphological changes have been observed.     

黑曲霉纤维素酶的化学组成

本文测定的黑曲霉纤维素酶各组分均为糖蛋白,但含糖量和组成各不相同,含糖量分别为：β－葡萄糖苷酶１１．３％,内切β－葡聚糖酶１１．８％,β－葡聚糖纤维二糖水解酶ＣＢＨ—１７．２％、ＣＢＨ－Ⅱ５．８％。各酶组分的氨基酸组成有一定的差异,但也有一些共同之处,即都含有较多的酸性氨基酸（Ａｓｐ、Ｇｌｕ）,碱性氨基酸（Ｈｉｓ、Ａｒｇ）含量较低。分析酶组分间的相似性时发现,β－葡聚精纤维二糖水解酶的ＣＢＨ－Ⅰ组分与内切β－葡聚糖酶在各种氨基酸的含量上较为相似,而同属于β－葡聚糖纤维二糖水解酶的两个组分ＣＢＨⅠ和ＣＢＨ—Ⅱ在氨基酸的含量上有一定的差异。     

HISTOLOGY OF MALFORMATIONS PRODUCED ON BEAN PLANTS BY CULTURE FILTRATE OF ASPERGILLUS NIGER

Postlethwait , S. N., and Roy W. Curtis . (Purdue U., Lafayette, Ind.) Histology of malformations produced on bean plants by culture filtrate of Aspergillus niger. Amer. Jour. Bot. 46(1) : 31-35. Illus. 1959.—The stem and leaf petioles of bean seedlings treated with culture filtrates of A. niger exhibit severe curvatures, increased diameter, reduced length, and irregular protrusions. These malformations result from an apparent partial loss of polarity of the cells in the actively growing region of young internodes and petioles. Enlargement and multiplication of cells in the affected regions occur mostly at an angle to the longitudinal axis of the plant. The effect is localized and the portion of the plant produced from the apical meristem subsequent to treatment matures in a normal way.