Productivity and Sustainability of Cotton (Gossypium hirsutum L.)–Wheat (Triticum aestivum L.) Cropping System as Influenced by Prilled Urea, Farmyard Manure and Azotobacter

Field experiments were conducted at Indian Agricultural Research Institute, New Delhi, during 2001–2002 and 2002–2003, to study the effect of inorganic, organic and Azotobacter combined sources of N on cotton (Gossypium hirsutum L.) and their residual effect on succeeding wheat (Triticum aestivum L.) crop. The results indicated considerable increase in yield attributes and mean seed cotton yield (2.33 Mg ha^?1) with the combined application of 30 kg N and farmyard manure (FYM) at 12 Mg ha^?1 along with Azotobacter (M₄). The treatment in cotton that included FYM, especially when fertilizer N was also applied could either improve or maintain the soil fertility status in terms of available N, P and K. Distinct increase in yield attributes and grain yield of wheat was observed with the residual effect of integrated application of 30 kg N ha^?1 + FYM at 12 Mg ha^?1 + Azotobacter. Direct application of 120 kg N ha^?1 resulted 67.4 and 17.7 % increase in mean grain yield of wheat over no N and 60 kg N ha^?1, respectively. Integrated application of organic and inorganic fertilizer is therefore, recommended for higher productivity and sustainability of the cotton–wheat system.     

中文棉花文献分布研究

针对中国科技信息研究所重庆分所编制的１９８９～１９９４年中文期刊数据库有关棉花生产的３６６６篇文献进行了年度、学科、在刊分布情况的分析，并根据布拉德福定律确定４４种重点刊物，可查阅到棉花生产文献的７３％。     

应用Bt生物制剂防治松毛虫试验

Bt可湿性粉剂（毒力效价8000IU），防治松毛虫效果较好，15天以后达到最高效果，最佳用药量750g/hm^2，平均效果能达92．54％。     

Resistance to plant viruses: Obtaining genes by non-conventional approaches

Summary Plant viruses cause considerable losses to crops and none of the three current approaches to disease control are likely to give the long-term answer. The new concept of non-conventional protection, in which the expression of a viral or virus-related sequence in the plant genome interferes with the virus infection cycle, holds considerable promise for designing new resistance or protection genes. A series of targets in the viral genome is identified and a range of mechanisms for attacking those targets is discussed. There are several current systems which have been proved to give protection, at least to a certain extent, and many systems which are being researched upon for the future. Some of these are described to give a picture of the current situation and of the thinking for the future. The problems of field deployment of the transgenic plants are discussed, especially those associated with the risk to the environment. Various questions which molecular biologists and plant breeders will have to consider include what are desirable characters to have in protection genes and how these new genes should be deployed.     

中国低酚棉品种资源群体特点及特异种质筛选

对１４５个国内外不同来源的低酚棉品种（系）的研究表明，中国低酚棉品种资源群体的基本特点是，皮棉产量的变异潜力较大；铃重、衣分、子指、衣指变异度较小，纤维品质性状的变异率表现相似。多数品种（系）的衣分偏低，子指较大，纤维强度低，细度中等，但纤维较长且整齐度好。在产量或品质性状方面，该资源群体含有一些特异种质；国内育成品种（系）在衣分、细度上可更好地提供优异的基因资源，而国外品种（系）在铃重，衣指，纤     

赤霉素对~(32)P在棉株体内运输分配的影响

20ppm赤霉素(GA)点滴当天开放的黄花,不管是正常受精、未受精或环剥未受精,对~(32)P向幼铃中的运输都具有明显的调配作用。而全株喷洒GA则阻抑~(32)P向幼铃中运输分配。GA和矮壮素(CCC)混合喷洒全株,可获得与用GA点滴黄花子房类似的结果,~(32)P运输到幼铃中的总量明显增加。GA通过影响物质运输分配使幼铃获得较多的养料供应,是其能防脱保铃的重要生理基础之一。此外,利用~(32)P示踪试验筛选对物质运输有调配作用的生长调节剂亦是一种简便可行的方法。     

机耕方法对潮土水分及棉花效益的影响

用不同耕作方法做了4年试验研究，对潮土水分及棉田产出情况进行调查分析，选出了适宜的机耕方法。     

麦后夏播棉育种农艺与经济性状的相关与协调

作者以育种实践中逐年资料的汇总，分析了麦后夏播棉育种的早熟性、丰产性与农艺性状(植株高度、主茎节间长度，果枝数、总果节数，第一节果枝着生节位和高度)和经济性状(结铃性、铃重、衣分、纤维长度、强度、细度和断裂长度)之间的相关与协调关系。提出了完善耕作改制，早熟育种增强科学的预性。尽可能减少和避免其盲目性的意见。     

湖北潜江市棉花生产存在的问题及对策

近年湖北潜江地区植棉面积稳定在30khm^2左右,面积、单产、总产、原棉收购量居湖北省前列。在历年种植过程中,出现了种植结构不当、主次不分、品种多乱杂、密度过稀、病虫蔓延、施肥不合理、化调技术不到位等问题,提出了调整种植结构、合理种植密度、选用优良品种、科学用肥、全程化调等解决对策。     

种衣剂包衣 防治棉苗病虫技术研究

试验结果表明，棉籽包衣是一项省工节本，防病治虫保苗效果好的新技术。针对我省沿江棉区生态条件和苗期病虫发生的特点，筛选适用的剂型。在本试验中以福美双７％，多菌灵５％、呋喃丹８％三者组配复制最为理想。