烟草潜叶蛾防治方法

烟草潜叶蛾，又叫马铃薯块茎蛾，俗称串皮虫、顺筋虫、洋芋蛆等。其幼虫喜食黄花烟草和红花烟草，蔬菜方面喜食马铃薯、茄子、番茄等。该虫在烟草方面主要危害烟草成株，烟苗次之，还危害晚烟株的生长点。受害烟叶调制后，潜痕成黑褐色或灰褐色，使烟叶产生杂色，在分级操作时，常使烟叶破裂，碎烟率增加，从而降低其商品等级和价格。     

变异与幸存

问：在电影《X战管》中，一部分人类自然地变异为拥有“难以置信的能力”的变种人。变种情况可能发生吗？至少在理论上有无可能性呢？比如将病毒的DNA注射到人类基因组中，是否会产生变种人呢？     

提高无性系茶苗移栽成活率的措施

无性系茶苗的移栽成活率是影响新建茶园成国的一项重要因子.成活率高,不仅成国快,而且使园相整齐一致,相反,成活率低,除了要费工费时不断地进行补植外,还会使茶树高低参差不齐,严重影响成园速度.目前,许多地方普遍反映无性系茶苗移栽成活率低下,甚至出现全军覆没的情况.据我们1993年在国营浮梁县广明茶场1992年的新辟茶园中调查,其无性茶苗移栽一年后的成活率只有30%—50%,这一问题已严重影响到我国无性系茶树良种的推广与应用.现在,我国的无性系良种茶园只占茶园总面积的5%—10%,而世界上一些主要产茶国的无性系良种茶园比例已经达到相当高的水平,如印度为30%,斯里兰卡为32%,肯尼亚为100%,日本为78.3%.因此,解决好无性茶苗移栽成活率问题已成为当务之急.本文就成活率低的原因及相应措施作一探讨.     

太阳系与典型植物细胞结构对应探析

本文通过对天体、生物细胞的结构研究，得出了太阳系与典型植物细胞结构具有相似对应关系的论断。     

水稻强化栽培技术体系的理论与实践

水稻强化栽培技术体系(System of Rice Intensification 简称SRI)是20世纪80年代由Henri de Laulanie神父在位于非洲大陆东南的岛国马达加斯加(Madagascar)提出的一种新的高产栽培技术体系,在该国应用多年并获得成倍的增产效果,单产从传统栽培法的4000公斤/公顷左右提高到1.6万公斤/公顷以上,无论是高原高产区、热带雨林边缘地带,还是北部的Andapa、西北部的Marovoay、南部的Fia-narantsoa,从近乎海平面到海拔1200米以上以及多种土壤类型中都取得明显的增产效果,被认为是能帮助水稻高产品种真正发挥其生物学潜力、遗传学潜力进而增产并节约成本,保障粮食安全,保护生态环境的一种栽培技术体系.     

跨性别交际失误的社会语言学分析

从语言变异的角度对跨性别交际失误现象进行社会语言学分析,社会文化因素的影响造成男女两性话语风格的不同,进而影响彼此的交流。在对《老友记》部分语料统计分析的基础上,我们发现社会的变化导致两性差异的缩小,两性话语风格随之变化,有些方面甚至出现与以往相反的趋势。两性话语风格的趋同将有助于减少跨性别交际中的失误现象。     

Spatial and temporal variations of zooplankton composition and quantity distribution in the upper waters around Nansha Islands

This study aims to examine spatial and temporal variations of zooplankton species composition, density and biomass distribution and community structure, based on the data obtained from three separate cruises carded out in November 1997, April and July 1999. Results show that 244 species of zooplankton and 8 groups of planktonic larvae were identified, which were dominated by copepods, followed by amphipods, ostracods and medusae. The total species were 201 and 198 for the cruises of November 1997 and July 1999, respectively, and no obvious seasonal variation of species richness was observed. The distribution of zooplankton species richness decreased from pelagic to coastal waters. Average richness of species in each station was higher in the cruises of November 1997（62） and April 1999（61） than in the cruise in July 1999 （56）, which was mainly a result from the pelagic or coastal water mass movement made by the monsoon. Zooplankton in the upper waters （0--100 m） around Nansha Islands belonged to the typical tropic pelagic fauna, most of them were pelagic warm-water species, followed by coastal warm-water species and euryhaline warm-water species. The number of dominant species ranged from 5 to 7 in each cruise. No obvious seasonal succession of dominant species was ob- served. Sagitta enflata, Cypridina narni, Cosmocalanus darwinii, Pleuromamma gracilis and Echino-pluteus larva were the main dominant species. The average of zooplankton biomass and density in three cruises were 31, 32, 28 mg·m^-3 and 31, 39, 35 ind·m^-3, respectively. Copepods were the most abundant, followed by chaetognaths. Zooplankton high biomass distributed mainly in the northwestern waters around Nansha Islands, and generally occurred in the areas of oceanic front and upweUing. The main reason for zooplankton quantity without obvious seasonal variation was the relative steady temperature dynamics in the waters around Nansha Islands.     

12世纪初至13世纪中期中国文学分流发展阶段性特征论略

中国文学发展进入到十二世纪初已呈分流之势,这一时期的文学分处三个不同阶段:文学过渡期、文学变异期、文学兴衰期.     

离子注入植物引起生物效应的机理

以３０￣２００ｋｅＶ的氮或磷离子束对玉米，小麦、水稻、黑麦等植物种子进行离子注入的处理，在处理的当代种子及以后几代种子中均出现显著的生物效应变异，如发芽率，生长速度植物株型等，染色体行为也出现异常。