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951.
952.
张丽红 《农产品加工.学刊》2012,(11):65-68
采用石蜡切片和光学显微技术,对生长在白城郊区和长春市不同生态环境下的001号和010号野生大豆(Glycine soja Seib.et Zucc).,进行同步栽培试验、同步结构比较研究。结果发现,生长在白城郊区的野生大豆根演化出比长春市生长的野生大豆较高级的抗盐结构。盐渍环境下白城郊区的野生大豆001号和010号的根变粗、周皮厚度增大、次生木质部导管孔径大、数量多,木质部管孔链多,长春市的野生大豆根较细,单管孔多。试验结果表明,野生大豆植物在盐碱环境胁迫下,根已经演化出颉颃逆境结构,这些变化证明盐胁迫直接影响了野生大豆植物体根形态结构的形成。 相似文献
953.
防治小麦赤霉病微生物菌株的筛选与利用 总被引:4,自引:0,他引:4
通过微营养培养分离拮抗菌和淀粉发酵法分离营养竞争性菌株,共分离到139个菌株,其中拮抗性菌株123个(118个细菌,5个放线菌)营养,竞争性菌株16个(3个酵母菌,13个细菌)。通过离体试验,30个拮抗菌仍表现出明显的防治效果,占总数的21.6%。经温室试验测定,9个菌株防治小麦赤霉病效果达70%以上,占总数的6.5%。经大田小区只有YN1、GJ6、Y-12等3个菌株分别表现出67.6%、64.9 相似文献
954.
The origination and status of the combinatorial chemistry are introduced and described and various approaches for building its libraries are mentioned and classified . Besides, the identification and characterization of the active compounds are recommended and the solid phase combinatorial synthesis and liquid phase combinatorial synthesis are presented. Meanwhile, some analytical methods including infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectrometry and so on are applied into combinatorial chemistry. Some powerful chemometric methods and techniques are then discussed for their applying into combinatorial chemistry. From the view of green chemistry, combinatorial chemical techniques could be regarded as "green" methods to fully utilize the resource and materials. When rational drug design is integrated into it, combinatorial chemistry can more efficiently and perfectly be used for innovation of the new drugs. Finally, the combinatorial chemistry is prospected for the application and development in future. 相似文献
955.
Giménez-Pardo C Martínez-Grueiro MM Gómez-Barrio A Rodríguez-Caabeiro F 《Veterinary research communications》2003,27(8):611-623
Cholinesterase (ChE) and acid phosphatase (AP) activities, but not alkaline phosphatase activities, were detected in cytosolic and membrane-bound fractions of adult and infective-stage larvae of levamisole-resistant and levamisole-susceptible Haemonchus contortus. In contrast to other gastrointestinal nematodes, the ChE activity was higher in L3 than in adults and, in both cases, was mainly associated with membranes. ChE activity was inhibited by Triton X-100 and was only detected in membrane-bound fractions when the detergent was removed. Differences between resistant and susceptible L3 were observed in the response to inhibitors (cytosolic fraction) and in the enzymatic content (membrane-bound fraction). Phosphatase activity was detected at acidic pH in all fractions, being higher in the adult than in the L3 stage. In the former, most of the enzyme was localized in the membrane-bound fractions, whereas in the latter it was mainly in cytosolic fractions. This difference could be correlated with the activity in the gut. In inhibition assays, a difference between cytosolic fractions from resistant and susceptible adults was observed in their response to 1 mmol/L tartaric acid. 相似文献
956.
Mamoru?SatoEmail author Wei?Wei Kenji?Watanabe 《Journal of General Plant Pathology》2003,69(6):391-396
A mulberry epiphytic Enterobacter cloacae MUL1 harbors plasmid pMUL1 encoding five drug-resistance genes. This plasmid was examined upon its conjugal transfer into epiphytic Erwinia herbicola on the phylloplane of mulberry and 12 species of weeds. The plasmid was transferred into Er. herbicola at a frequency of 10–5–10–3/recipient in mulberry and Lolium multiflorum LAM. 1–8 days after wound inoculation with 106–108/ml suspensions. In Chenopodium album L. and C. album L. var. centrorubrum, however, it was transferred only after wound inoculation with a 108/ml suspension, but not with 107/ml or 106/ml suspensions, owing to the weak epiphytic fitness of Ent. cloacae on these weeds. Transconjugants were also obtained for seven other species of weeds in the case of inoculation with a 108/ml suspension. In contrast, when bacterial suspensions were sprayed on mulberry leaves with or without fresh wounds, transconjugants were obtained only in wounded leaves, which were considered suitable for bacterial conjugation. These findings suggest that epiphytic bacteria, including Ent. cloacae and Er. herbicola, may be carriers of drug-resistance genes distributed among plant pathogenic bacteria in nature. 相似文献
957.
巨型艾美耳球虫(Eimeria maxima)地理株研究Ⅰ.11株巨型艾美耳球虫的分离与基本特征 总被引:6,自引:0,他引:6
采用单卵囊分离技术,从江苏、安徽、山东、广东、福建和上海等省(市)10个地区的鸡场及美国的球虫病疫苗中获得了11株纯种球虫。根据下列特征:(1)卵囊的大小、形态和颜色;(2)孢子囊的大小和形态;(3)形状指数(卵囊长宽之比);(4)虫体肠道中的寄生区;(5)肉眼病变的性质;(6)最早孢子发育时间;(7)最短的潜在期,对这11株纯种球虫作了鉴定。结果表明,11株纯种球虫均为巨型艾美耳球虫(Eimeria maxima Tyzzer,1929)地理株。应用SPSS软件系统,对各株进行描述性统计和方差分析,结果显示,11株间存在不同程度的差异,而美国株与国内各株均有显著差异。 相似文献
958.
棉花抗黄萎病品种选育方法探讨 总被引:11,自引:0,他引:11
在棉花抗病育种中,通过病圃或重病地选择抗病单株是常规的选育方法,但其在抗黄萎病育种中的效果并不理想。如何提高抗黄萎病育种效率,促进育种进程是目前急需解决的问题之一。为此,19982002年我们在北京人工病圃,对不同抗病杂交组合和选育方法的选育效果进行了研究。结果表明,在双亲本均为抗(耐)品种的杂交后代群体中,以9月中旬是抗病还是感病并没有多少关联,对黄萎病抗性的选育应选群体抗病性强的株系或组合,以其丰产性为主要选育目标;只有抗与抗(或高耐)的组合中才能选出黄萎病抗性更高的株系;在抗(耐)品种中,后期无论是抗或感的单株其后代的抗病性差异不明显 相似文献
959.
960.
从25个鸡场疑似卵黄性腹膜炎的病料中分离到了18株大肠杆菌和2株沙门氏菌,经大肠杆菌O血清型鉴定,用优势血清型菌株分别接种改良的血清-葡萄糖-肉汤培养基所研制的多价油乳剂灭活苗,在开产前接种鸡群预防产蛋鸡卵黄性腹膜炎,预防效果良好,而采取多价油乳剂灭活苗预防接种配合活菌制剂益生素的使用,预防效果更佳。使用优势血清型菌株筛选的敏感药物硫酸丁胺卡那霉素、强力霉素同时配合清瘟败毒散和VC对卵黄性腹膜炎鸡群进行治疗,治疗效果良好。 相似文献