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91.
92.
利用玫瑰黄链霉菌Men-myco-93-63 菌株的固、液体发酵物防治设施番茄和黄瓜根结线虫,研究其对根结线虫的防效以及施用生防菌对土壤微生物区系的影响。结果表明:Men-myco-93-63 菌株固体发酵物1 V∶200 V对黄瓜和番茄根结线虫病的防效分别达到了65.62% 和57.69%;施用生防菌使得植株根际土壤中细菌数量增加了19.57%,放线菌数量增加了316.67%,真菌数量降低了28.57%,以上3 种可培养微生物总量由7.4×106 cfu·g-1增加到16.75×106 cfu·g-1,增加了126.35%。 相似文献
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根结属(Meloidogyne Gǒldi)线虫必须寄生于寄主植物根系并获取所需的全部营养,才能完成其完整的生活史。此种寄生行为会对植物造成一定的伤害,而寄主植物的反应也会对根结线虫产生显著的影响,从而引发线虫的种种高度专化性适应。寄生过程引起的根结线虫与寄主植物之间的一系列互作反应,包括根结线虫对寄主植物的致病现象,寄主植物的感病反应和抗病反应。根结线虫与寄主的关系是在长期进化过程中形成的。 相似文献
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A study was done on the relationship between Aphelenchoides besseyi and the symptoms of small grains and erect panicles. This is an important rice disease in Jiangsu Province, China. A. besseyi was extracted from small grains and erect panicles and cultured artificially, and then inoculated into bud and leaf sheaths of seedlings of two Oryza sativa cultivars, namely Zhendao 2 and Wuyunjing 7 in a greenhouse. The effect on rice growth, in particular the small grains and erect panicles, was revealed by the extent of the disease, seed expansion stages, nematode load, and nematode mortality. In contrast to healthy seedlings, the height, length, and the numbers of spikelets of unhealthy panicles of Zhendao 2 were decreased by 6.7, 16.4, and 13.5%, respectively. Before anthesis, nematodes were attracted to the leaf sheath and apical meristem, nematode load increased by 40%; after anthesis, nematodes occurred in spikelets principally and the number increased by 90.8%. The percentages of infected seeds and nematode load were highest in plump seeds and lowest in empty seeds. Nematode mortality on grain with normal endosperm was lower than seeds with abnormal endosperm. Results indicated that A. besseyi was the pathogen in rice with the symptoms of small grains and erect panicles. Wuyunjing 7 manifests only the small grains and erect panicles symptoms and not the symptoms of leaf white-tip. These symptoms of small grains and erect panicles are new symptom records for the disease caused by A. besseyi on rice. 相似文献
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捕食线虫性真菌的分离培养技术与形态学 总被引:19,自引:3,他引:16
分离培养捕食线虫性真菌的最佳培养基为 0 .4g/ L 玉米粉琼脂培养基 (CMA) ;0 .4g/ L 玉米粉液体培养基可作为保存菌种培养基。在分离培养过程中 ,必须加入活的线虫第 3期幼虫 ,以诱导菌株产生捕食性器官——菌环、菌网 ,并与其他真菌鉴别。捕食线虫性真菌有菌丝和孢子 2种形态 ,其发育时期不同。本试验分离的少孢节丛孢菌(Arthrobotrys oligospora) ,菌丝发达 ,无色有隔 ,隔距不等 ;分生孢子梗直立不分支 ,分生孢子围绕着分生孢子梗呈轮状排列 ,似梅花瓣状 ,2层以上 ;孢子呈倒卵形 ,丰满无色 ,有横隔 ,游离端大而钝圆 ,梗端小而稍尖。 相似文献
99.
A previous RFLP analysis showed that the Aegilops ventricosa chromosome 6MV which compensates for the absence of 6D in 6MV (6D) wheat substitution lines was a 2/6 translocated chromosome, either 2S–6S.6L or 2S–6L.6S. The distal part of its long arm consists of a translocated segment belonging to homoeologous group 2. Chromosome 6MV carries a gene(s) for resistance to cereal cyst nematode. In order to define the part of 6MV (2S or 6S or 6L) involved in this resistance, addition lines with a 6MV deleted either for its short arm or for the distal part of its long arm were evaluated. It was shown that the gene(s) is carried by the group 2 translocated segment. The hypothesis that the gene(s) could be allelic to Cre2, another gene conferring resistance to the nematode introduced into the wheat complement from Ae. ventricosa is discussed. 相似文献
100.
Genes from wild species of the Procumbentes section can be transferred to sugar beet chromosomes via translocations. Since large translocations, including for example a gene for nematode resistance, generally result in meiotic disturbances, there is a need to select new diploid resistant beets from progenies of monosomic wild beet addition lines. A dispersed repetitive DNA probe, which is closely correlated with the resistance gene and hybridizes exclusively with wild beet DNA, appears to be highly superior to selection based on isozyme markers. Characteristic ‘fingerprints’ on the available monosomic addition lines reveal the existence of at last 5 different chromosomes in the wild species each housing a gene for nematode resistance. This probe can be used advantageously to identify individuals carrying the intact or fragmented wild beet chromosomes, or even various amounts of translocated chromatin. Strategies are discussed for the identification of new translocation types using straightforward squash dot or Southern hybridization techniques in combination with the wild beet DNA probe. 相似文献