Screening and Verification of Low Nitrogen Tolerant and Nitrogen Sensitive Cotton Germplasm

[Objective] The aim of this study is to evaluate nitrogen efficient cotton germplasms and improve nitrogen use efficiency. [Method] Eighty cotton germplasms were selected and evaluated in the hydroponic experiment under low (0.25 mmol·L^－1) and high (5 mmol·L^－1) nitrogen concentration. Different traits for screening were identified and nitrogen use efficiency types were classified. Field experiments were also performed for comparison and confirmation of the identified germplasms. [Result] The results showed that there were significant differences in the total plant dry matter, shoot nitrogen accumulation and nitrogen absorption efficiency in cotton germplasms at the two nitrogen levels. Based on coefficient of variation, principal component analysis and correlation, six traits including total plant dry matter, shoot dry matter, root dry matter, total nitrogen accumulation, shoot nitrogen accumulation and nitrogen absorption efficiency were used as screening indicators. According to the Heatmap clustering analysis and the nitrogen efficiency comprehensive index, two germplasms (Lu05R59 and CCRI 69) were identified as low nitrogen tolerant and nitrogen efficient, and two germplasms (Coker 201 and Xinluzhong 30) as low nitrogen sensitive and nitrogen inefficient. The results of field experiment were consistent with the results of the hydroponic culture at the seedling stage. [Conclusion] It was finally determined that Lu05R59 and CCRI 69 were the low nitrogen tolerant and nitrogen efficient germplasms, and Coker 201 and Xinluzhong 30 were low nitrogen sensitive and nitrogen inefficient germplasms. The results of these studies provide the possibility for screening and rapid identification of nitrogen use efficiency in cotton at the seedling stage, and provide the ideal materials and theoretical basis for further study of cotton nitrogen efficient.     

蜂蜜的矿物质与营养

等离子体光谱分析表明：研究的１０种蜂蜜均含有人体所需的多种矿物元素。人体血浆中Ｃｕ／Ｚｎ，Ｋ／Ｎａ，Ｃａ／Ｍｇ比与身体状况密切相关。研究表明荞麦蜜的Ｃｕ／Ｚｎ比最高，Ｋ／Ｎａ比也较高，而Ｋ／Ｎａ，Ｃａ／Ｍｇ比以枣花蜜为最高。食用蜂蜜的人将受蜂蜜中矿物元素的影响而改善这些价值，有益于健康。     

陕西蚕病流行规律分析

通过历年盒种产茧量、干茧病蛹及蚕期蚕病调查，得知养蚕技术、养蚕形式、地理位置、气候条件影响陕西蚕病的流行分布。近几年危害生产的主要是僵病、多角体病及微粒子病。各地由于养蚕形式、技术、地理及气候差异，蚕病发生轻重不同。僵病流行比其它蚕病受养蚕技术、地理、气候影响更明显。多角体病流行与僵病不同，有较明显的垂直传播特点。微粒子病自１９８９年发现之后，蔓延迅速，其病原首先来自从疫区调入的带毒蚕种。     

山西省蚜虫消长与玉米矮花叶病流行关系

玉米矮花叶病是非持久性病毒——MDMV 引起。病毒介体是蚜虫,在山西省主要是麦二叉蚜(Schizaphis graminum Rond)、禾缢管蚜(Rhopalo-siphum padi Linnaeus)、玉米蚜(Rhopalosiphum maidis Fitch)、桃蚜(Myzus persicae Sulzer)和棉蚜(Aphis gossypii Glover),麦无网长管蚜[Acythosiphum dirhodum(Walker)]的传毒能力未定。实验表明,传毒蚜虫饲毒最适时间5～30分钟,接毒最适时间30～60分钟,持毒期限6～7小时,有效传毒蚜数3～5头。气温20℃麦二叉蚜的传毒效能最高,是春播玉米的主要传毒蚜虫。传毒蚜的高峰期后16～30天是发病高峰,以玉米拔节至孕穗间发病最快,抽雄后渐缓。病害的发生流行取决于毒源量、传毒蚜的虫口密度及其自然带毒率的提高,这过程进展的快慢是受时间和空间的影响。     

应用花药培养技术培育苹果新类型

通过对苹果不同品种花培植株的试管苗及其高接树的染色体数目观察,看到大部分为单倍体,还有其他倍性的植株.幼龄期元帅花培植株的植物学性状与原品种元帅之间有显著差异,表现分枝多、有针刺、叶片小而薄、茸毛少、有缺刻等野生性状.在花培植株之间,也表现有明显的差别.田间高接后,花培植株随树龄增长逐渐向栽培性状转化,元帅花培植株元80—3已开始结果,表现出明显的短枝型特征.     

巴旦杏在甘肃河西地区引种培育问题的探讨

该文通过分析巴旦杏在甘肃河西地区引种培育过程中出现的问题,总结出用容器育苗和大田开沟点播相结合来培育接穗,以山桃为砧木嫁接巴旦杏的引种驯化技术.结果表明,容器培育接穗比直接大田点播出苗率、成活率分别提高了10%和15%;巴旦杏与山桃嫁接表现出极好的亲和性,嫁接成活率为90%.     

饲喂柠条对肉兔生产性能及胴体性状影响的研究

选用45～48日龄平均体重1050g的伊普吕(父系)幼兔64只,分成4组,进行柠条饲喂肉兔试验.对照组饲粮中谷草比例为33.4%,试验Ⅰ、Ⅱ、Ⅲ组分别用10%、20%和33.4%柠条替代等比例谷草.48天试验结果为:对照组、试验Ⅰ、Ⅱ、Ⅲ组日均采食量、日增重、料肉比分别为89.84g、92.95g、90.77g、79.95g,22.60g、23.30g、19.24g、17.90g,3.98:1、3.99:1、4.72:1、4.47:1.试验Ⅰ、Ⅱ组与对照组日采食量、日增重、料肉比差异不显著(P＞0.05);屠宰试验结果为:试验Ⅰ、Ⅱ与对照组在胴体重、屠宰率、净肉率、肉骨比、心脏、肺脏、肝脏、肾脏等指标方面无显著差异(P＞0.05);而试验Ⅲ组日采食量、日增重均显著较对照组差(P＜0.05).试验结果表明:生长肉兔饲粮中添加10%～20%柠条粉是可行的,且饲粮成本较低.     

抗鸡传染性腺胃炎酶标抗体的制备和应用

在前期从患病鸡腺胃内分离到呼肠孤病毒的基础上，以该病毒为免疫原对兔进行免疫制备高免血清，分离纯化IgG，进行辣根过氧化物酶（HRP）标记，并用ELISA双抗体夹心法对山东省青岛、枣庄、泰安等地区采集的传染性腺胃炎的腺胃样品进行检测，结果表明制备的抗鸡传染性腺胃炎呼肠孤病毒的酶标抗体检测传染性腺胃炎特异性强、灵敏度高、较简便。     

母牛一胎双犊技术的研究

选择9头母牛先行人工授精、7天后再移植冷冻胚胎以生产双犊。试验结果表明,母牛产双犊达44.44%(P<0.01)。提示:采用A(I人工授精)+ET(胚胎移植)是提高母牛双犊率的有效技术措施之一。