转基因水稻对稻瘟病的抗性研究   总被引：6，自引：0，他引：6  

杨祁云  许新萍  朱小源  冯道荣  李宝健 《植物病理学报》2003,33(2):162-166

 采用苗期初筛、复筛、抗谱测定和田间自然诱发试验等不同鉴定方法,对经分子检测证明已整合有碱性几丁质酶基因和β-1,3-葡聚精酶基因的22个转化系的转基因水稻植株进行稻瘟病抗性鉴定研究,筛选出对稻瘟病的抗性比原种对照七丝软占有明显提高的一系列转基因水稻品系,其中表现高抗的有来自F4-9转化株系的7个品系。高抗材料的R7代品系,经室内抗谱测定及田间病圃试验结果,仍然表现高抗稻瘟病。本研究通过转基因技术,成功地将优质感病品种改良成高抗品系,研究结果证明了利用基因工程手段培育抗病水稻新品种是一个非常有希望的育种途径。  相似文献   

昆虫病原线虫固体培养系统中主要培养参数的优化     

韩日畴  李丽英 《昆虫天敌》1997,19(2):75-83

本文根据系统分析方法，利用正交旋转组合设计于固体培养系统中测定培养基的样量、细菌培养时间、接线虫量和线虫培养时间对Ｓｔｅｉｎｅｒｎｅｍａｃａｒｐｏｃａｐｓａｅ 和Ｈｅｔｅｒｏｒｈａｂｄｉｔｉｓｂａｃｔｅｉｐｈｏｒａ产量的综合影响，确定虫的优化培养参数。  相似文献   

肉仔鸡生长过程中行为与产热的变化     

任建军  高文婷  邱泽文  王靖宇 《畜牧与兽医》2004,36(1):12-14

研究肉仔鸡成长过程中行为变化对产热量的影响 ,将 2日龄肉仔鸡 36只分为自由摄食、 50 %摄食和绝食 3组进行观测。立位行为集中在明期 ,特别是摄食 30min前后 ,暗期几乎没有出现立体行为。 2日龄时 ,每天约有 70 0min是立位的 ,其后 ,随着日龄的增加而减少。在自由采食区 ,公雏比母雏摄食时间长。 50 %摄食区较自由采食区的摄食时间少。在绝食区 ,随着日龄的增加 ,公母的立位时间呈现减少倾向。 2 1日龄之前随着日龄的增加其摄食时间也增加 ,其后呈现相反倾向。产热 (HP ,kJ/kg0 75)与摄食时间有相同倾向。在 2 1日龄前公雏的HP比母雏低 ,2 1日龄后母雏比公雏低。 1天中各个区的HP活动规律是摄食后 1h内最高 ,暗期降低 ;限制摄食量后 ,HP降低 ,明期和暗期的HP差也随之减小  相似文献   

植物生长物质的使用与绿色果品生产   总被引：3，自引：1，他引：3  

汪良驹  姜卫兵  刘晖  刘卫琴 《园艺学报》2004,31(2):259-262

 针对人们对植物生长物质的种种偏见，阐述了植物激素与动物激素以及植物生长调节剂的重要区别，提出了植物激素对人体无毒性，植物生长调节剂可以运用于大多数绿色果品生产的建议。  相似文献   

枯草芽孢杆菌G3菌株的抗菌物质及其特性   总被引：29，自引：3，他引：29  

顾真荣  吴畏  高新华  马承铸 《植物病理学报》2004,34(2):166-172

 产几丁质酶枯草芽孢杆菌G3菌株的固体培养物在黄瓜灰霉病菌和番茄叶霉病菌抑菌试验中证实,抑菌活性物质存在于过滤上清液中,它们是从酸沉淀物中提取出的伊枯草菌素、生物表面活性素和存在于盐析粗蛋白中的几丁质酶。在叶霉孢子萌发试验中,伊枯草菌素微弱地抑制孢子萌发但强烈破坏芽管和新生菌丝;生物表面活性素和几丁质酶则强烈抑制孢子萌发并长久性地抑制芽管伸长。在PDA平板上的灰霉菌丝抑菌试验中,伊枯草菌素抑制菌丝生长,引发菌丝顶端膨大,形成泡囊,泡囊破裂后原生质外泄;几丁质酶抑制菌丝生长,引发产生不规则的菌丝团;生物表面活性素在平皿上对菌丝则不显示出抑菌活性。  相似文献   

Transgenic cucumber expressing an endogenous class III chitinase gene has reduced symptoms from Botrytis cinerea     

Kyutaro Kishimoto  Yoko Nishizawa  Yutaka Tabei  Masami Nakajima  Tadaaki Hibi  Katsumi Akutsu 《Journal of General Plant Pathology》2004,70(6):314-320

A class III chitinase gene (CHI2) is induced in cucumber plants (Cucumis sativa L.) in response to infection by pathogenic microorganisms. Infection of Botrytis cinerea, causal agent of gray mold disease on cucumber, also induces CHI2 expression. To investigate whether CHI2 is involved in resistance to gray mold disease, transgenic cucumber plants were produced to overexpress the CHI2 gene. One line was analyzed in detail in terms of disease resistance. The transgenic cucumber plant (CC2) constitutively expressed CHI2 and reduced the symptoms of B. cinerea for 4 days after inoculation compared with nontransgenic plants. However, this inhibitory effect was not absolute, and CC2 eventually developed serious disease symptoms. Chitinase activity of the crude extract from CC2 leaves was higher than that from nontransgenic plants. A high-molecular-weight fraction containing CHI2 from CC2 leaves had fungistatic activity against B. cinerea. Interestingly, the low-molecular-weight fraction from CC2 leaves with CHI2 removed also had fungistatic activity against B. cinerea. Not only the introduced chitinase activity but also the endogenous defense reactions activated by overexpression of CHI2 may be involved in the enhanced gray mold disease resistance in CC2.  相似文献   

抗生素工业化生产中一级种子罐染菌原因及解决方法   总被引：1，自引：0，他引：1  

高自召 《中国兽药杂志》2004,38(1):51-53

抗生素工业化生产中,菌种往往需要扩大繁殖到一定的数量后再进入发酵罐.在一级种子制备过程中,引起染菌的因素很多,极大地影响了抗生素生产的产量和质量.解决一级种子罐染菌的方法,除制定科学的岗位SOP并不断提高操作者的技能外,更重要的是要加强工艺管理,树立以预防为主的思想,根据微生物特性,强化环境清洁,加强设备清洁、维修,操作时实行定人、定操作.  相似文献   

安宁河流域黑麦草、白三叶的生长测定     

傅平  敖学成  王世斌  王同军  佘陆均 《四川畜牧兽医》2004,31(12):24-25

在最冷的12月至2月对四川凉山州安宁河流域的黑麦草、白三叶进行生长测定,结果证实,在当地建高产人工草地可作当家品种,冬季无停止生长期,最低产量可在5000kg以上,放牧利用的停牧周期在一月以内为好,预计年刈割周期次数为6～8次。  相似文献   

Significance of local immunity in hen reproductive organs     

Yukinori YOSHIMURA 《Animal Science Journal》2004,75(3):183-191

The current paper describes aspects of local immunity in the ovary and oviduct, and the significance of immunity to reproductive functions in hens. The immunocompetent cell populations in the ovary and oviduct change with a positive correlation to sexual activity, and gonadal steroid is one of the key factors in the increase. Local immune responses mediated by major histocompatibility complex class II and T cell subsets occur in response to infection by Salmonella enteritidis, which may contaminate eggs. In the ovary, immunocompetent cells are also suggested to play roles in the regulation of ovarian functions. Macrophages and T cells are likely to enhance the regression of atretic follicles to maintain the ovarian tissue microenvironment. Autoantibodies to ovarian tissues appeared in the hens with low egg laying frequency, suggesting that the auto‐antibodies may be one of the factors in the decline of egg production. In the oviduct, local immunity possibly has a role in the selection of sperm, though the immunoreactions may also affect sperm survival leading to the decline in fertility. The concentration of yolk IgY, which plays a role in maternal immunity transmission, significantly decreases with the aging of birds, whereas it is significantly increased by estrogen. Therefore, the immune system plays significant roles not only in defense against infection, but also in the functions of reproductive organs. Investigations on the local immune system in the reproductive organs and factors affecting it are of importance for the production of sterile eggs and improvement of reproductive functions.  相似文献   

Effect of bilateral cecal ligation on use of dietary energy in growing chickens     

Kunio SUGAHARA  Mako MATSUMOTO  Motoko YAMADA  Fumiaki YAOSHIZAWA  Yutaka KARASAWA 《Animal Science Journal》2004,75(5):431-434

In order to determine the role of the cecum on energy use in growing chickens, metabolizability of the dietary energy and energy expenditure were examined in the week following bilateral ligation and washing out of the cecum. Apparent metabolizable energy (AME) values were 14.30 and 13.69 kJ/g air‐dry matter for sham‐operated and cecally ligated chickens, respectively. These values were found to be significantly different (P < 0.05). Although AME intake and fasting heat production were decreased by cecal ligation, the distribution of AME (measured as fasting and feeding heat production, as well as heat increment and energy retention, as a proportion of AME intake) was not affected. These results suggest that the cecum helps chickens extract AME from corn‐soybean type diets with little, if any, effect on AME use, based on the present study of growing chickens in the week following cecal ligation.  相似文献