应用天然植物产品川楝素防治菜青虫试验   总被引：25，自引：2，他引：23       下载免费PDF全文

赵善欢  曹毅  彭中健  黄家总 《植物保护学报》1985,12(2):125-132

川楝素是从川楝树分离得到的一种四环三萜类化合物。它对菜青虫有较强的拒食及毒杀作用,因此施药后能很快地得到保护叶片的效果,且在田间也有较长的残效期。经试验,川楝素对天敌凤蝶金小蜂及蚜茧蜂安全。  相似文献   

我国植物病理学发展的方向问题     

裘维蕃 《中国农业大学学报》1990,(4):353-356

1 植物病理学的基本任务植物病理学担负着病理和防治两方面的任务。对人医或兽医来说,病理和临床往往是分工的,而植物病理并没有那样的分工,也就是说它必须兼顾病理和临床。另外一个特点便是植物种类繁多,而每一种植物又各有其自己特殊的多种病害。一个植物病理学家最多只能掌握几种主要农作物的重要病害及其防治要点。可是实际上,经常会遇到许多从未见过的新病  相似文献   

耐病毒诱导剂NS-83生理活性的测定   总被引：2，自引：0，他引：2  

李怀方  雷新云  裘维藩 《植物病理学报》1987,17(3):147-152

 在多种生物测定系统中对比TNS-83与萘乙酸、赤霉酸和激动素的生理活性,证明NS-83确实具有生长素、赤霉素和细胞分裂素的某些生理功能,但又不完全相似于这些激素.在它的组分中可能存在一种新型的植物生长控制物质,值得深入研究.对于这些生理活性与植物病毒病害控制的关系进行了讨论.  相似文献   

防治水稻害虫新型杀虫剂硫环杀的试验研究   总被引：1，自引：0，他引：1  

尚稚珍  邹永华  王银淑  孙遂奎  闻善娟  赵善欢  黄炳球  胡美英 《植物保护学报》1982,9(3):211-216

通过三年室内和田间试验,发现硫环杀对防治水稻害虫具有突出的优点,它与杀螟丹、杀虫双都属于同类新型结构的杀虫剂。硫环杀田间亩用量75克防治水稻二化螟、三化螟其效果与杀虫脒、杀螟丹、杀虫双在一个水平上。根区深层施药可兼治水稻多种害虫,并可提高防治效果。残效期可维持7～14天,田间施药1～2次可控制螟害,它不仅具有良好的内吸和触杀作用,还兼有胃毒和熏蒸作用。硫环杀属神经毒剂,对螟虫具有特殊的中毒症状及毒杀机制,对高等动物属中等毒性,无致癌、致突变作用,也不会引起畸胎的形成。根据硫环杀的理化特性、代谢、转化等残留分析,它积累在环境中或食物链上可能性不大,可以取代有机氯农药,其特殊的毒杀机制在克服害虫抗药性方面,可能作为轮换的一个新品种。它是一个很有希望的杀虫剂。  相似文献   

Thiolysis as an activation process in N-sulfenylated derivatives of methylcarbamate esters     

Y.C. Chiu  A.L. Black  T.R. Fukuto 《Pesticide biochemistry and physiology》1975,5(4):359-366

An activation process involving thiolytic cleavage of the NS bond in several N-sulfenylated-N-methylcarbamates was shown to be a nonenzymatic reaction. Biological tissues, including subcellular fractions of mouse liver; heat-denatured microsomal enzyme, mouse blood, commercial protein, and housefly homogenate, as well as thiol reagents, readily effected the cleavage of the NS bond. The inhibitory effect of sulfhydryl inhibitors such as N-methylmaleimide and p-chloromercuribenzoate in the incubation system suggests that thiol residues in biological tissue are involved in this thiolytic reaction. Results from kinetic and product analysis also support this conclusion.  相似文献   

Major pol gene progenitors in the evolution of oncoviruses   总被引：24，自引：0，他引：24  

I M Chiu  R Callahan  S R Tronick  J Schlom  S A Aaronson 《Science (New York, N.Y.)》1984,223(4634):364-370

The genetic relationships among molecularly cloned prototype viruses representing all of the major oncovirus genera were investigated by molecular hybridization and nucleotide sequence analysis. One of the major progenitors of the pol genes of such viruses gives rise to mammalian type C viruses and another gives rise to type A, B, D, and avian type C oncoviruses. Evidence of unusual patterns of homology among the env genes of mammalian type C and D oncoviruses illustrates that genetic interactions between their progenitors contributed to the evolution of oncoviruses.  相似文献   

赤豆(Phaseolus angularis Wight)花叶病毒的初步研究   总被引：1，自引：0，他引：1  

韦石泉  裘维蕃 《植物病理学报》1964,7(1):67-78

 赤豆花叶病在北京相当严重,病株达10-40%。病株分离物用常规汁液摩接法接于赤豆幼苗,初生透明褪绿小点或轻微斑驳,后表现花叶及疱斑,重者叶扭折畸形,叶缘缺刻,株矮,荚小而少。同一病毒接种于豇豆(Vigna sinensis L.)上,与赤豆上的症状无明显的差别。这个病毒的物理属性为:致死温度60-65℃ 10分钟,稀释限点1:3000-1:4000,体外存活仅24小时。病株所结种子有传毒能力,视寄主不同而有所差异,赤豆种子发病率仅1.6%,而豇豆种子发病率为17.2%。桃蚜、豆蚜、棉蚜及菜缢管蚜皆能传播此病毒。寄主范围为多种豆科作物,如豇豆、藊豆、大豆、蚕豆及芸豆、豌豆,黎科的菠菜,十字花科的桂竹香、紫罗栏等。除在桂竹香上生褪绿小点外,余均表现系统花叶症。但不侵染紫云英、绿豆、山扁豆、三叶草、苜蓿、黄瓜、南瓜、烟草、藜、千日红、苋及芹菜等。据此,作者等认为它不是黄瓜花叶病毒的株系,亦不同于日野的赤豆花叶病毒(豇豆花叶病毒的一个株系),与典型的长豇豆花叶病毒有较多的共同点,因此认为是长豇豆花叶病毒(AbMV)种羣中的一个新株系。  相似文献   

Aryl N-hydroxy- and N-methoxy-N-methylcarbamates as potent reversible inhibitors of acetylcholinesterase     

Y.C. Chiu  M.A.H. Fahmy  T.R. Fukuto 《Pesticide biochemistry and physiology》1973,3(1):1-6

Several aryl N-hydroxy- and N-methoxy-N-methylcarbamates were examined as inhibitors of bovine erythrocyte acetylcholinesterase (AChE). These carbamate derivatives were generally strong inhibitors of AChE, but, unlike the typical N-methyl- and N,N-dimethylcarbamates which are carbamylating agents, they proved to be reversible, competitive inhibitors of the enzyme. The values for the dissociation constant (K_a) for the enzyme-inhibitor complex to enzyme and inhibitor were in the range of 2 × 10^?5?1 × 10^?7M.  相似文献   

Antitumor Effects of a Sesquiterpene Derivative from Marine Sponge in Human Breast Cancer Cells     

Li-Yuan Bai  Jui-Hsin Su  Chang-Fang Chiu  Wei-Yu Lin  Jing-Lan Hu  Chia-Hsien Feng  Chih-Wen Shu  Jing-Ru Weng 《Marine drugs》2021,19(5)

In this study, the anti-proliferative effect of ilimaquinone, a sesquiterpene derivative from the marine sponge, in breast cancer cells was investigated. Ilimaquinone inhibited the proliferation of MCF-7 and MDA-MB-231 breast cancer cells with IC₅₀ values of 10.6 μM and 13.5 μM, respectively. Non-tumorigenic human breast epithelial cells were less sensitive to ilimaquinone than breast cancer cells. Flow cytometric and Western blot analysis showed that ilimaquinone induced S-phase arrest by modulating the expression of p-CDC-2 and p21. Ilimaquinone induces apoptosis, which is accompanied by multiple biological biomarkers, including the downregulation of Akt, ERK, and Bax, upregulation of p38, loss of mitochondrial membrane potential, increased reactive oxygen species generation, and induced autophagy. Collectively, these findings suggest that ilimaquinone causes cell cycle arrest as well as induces apoptosis and autophagy in breast cancer cells.  相似文献   

Inhibitory effect and mechanisms of an anthocyanins- and anthocyanidins-rich extract from purple-shoot tea on colorectal carcinoma cell proliferation     

Hsu CP  Shih YT  Lin BR  Chiu CF  Lin CC 《Journal of agricultural and food chemistry》2012,60(14):3686-3692

One newly bred variety of tea cultivar, purple-shoot tea, was selected to evaluate its antiproliferative effects on colorectal carcinoma cells, as well as normal colon cells. The phytochemicals and identified catechins of purple-shoot tea extract (PTE) were significantly higher than that of ordinary tea, especially the anthocyanins (surpassed by 135-fold) and anthocyanidins (surpassed by 3.5-fold). PTE inhibited the proliferation of COLO 320DM (IC(50) = 64.9 μg/mL) and HT-29 (IC(50) = 55.2 μg/mL) by blocking cell cycle progression during the G(0)/G(1) phase and inducing apoptotic death. Western blotting indicated that PTE induced cell cycle arrest by reducing the expression of cyclin E and cyclin D1 in COLO 320DM and the upregulation of p21 and p27 cyclin-dependent kinase inhibitors in HT-29. Two cells treated with PTE also indicated the cleavage of PARP, activation of caspase 3, and an increased Bax/Bcl-2 ratio. Our results showed that PTE is a potential novel dietary agent for colorectal cancer chemoprevention.  相似文献