棉田大丽轮枝菌微菌核的空间分布及其抽样技术  

Spatial Pattern and Sampling Method for Microsclerotia of Verticillium dahliae in Soil of Cotton Field

作　　者：商文静[1,2] 魏锋[1] 冯小军 朱荷琴[2] 杨家荣[1] 胡小平[1] 

机构地区：[1]旱区作物逆境生物学国家重点实验室,西北农林科技大学植保学院,陕西杨凌712100 [2]棉花生物学国家重点实验室,中国农业科学院棉花研究所,河南安阳455100 [3]陕西省植保总站,西安710003

出　　处：《西北农业学报》2014年第4期192-197,共6页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家自然科学基金(31371888);棉花生物学国家重点实验室开放课题基金(CB2013A20);高等学校学科创新引智计划(B07049)

摘　　要：大丽轮枝菌可侵染660多中植物，由其引致的黄萎病具有危害性大、难于防治等特点。微菌核是大丽轮枝菌在土壤中的主要存活结构和初侵染源，研究其在土壤中的分布特征及抽样技术，对于准确预测黄萎病的发生为害状况具有重要意义。土壤微菌核调查结果表明，在0～20cm土壤中，微菌核主要呈聚集或均匀分布，随密度而变化。建立的理论抽样数模型为：n=1．4679（t／D）2m-1.2604。利用得到的棉田土壤大丽轮枝菌微菌核调查的序贯抽样模型计算，最多只需抽取35个样点。对各等距机械抽样方法比较后，认为实际中用双对角线取样比较合适，取样数量因土壤中微菌核的密度而异。Verticillium dahliae can infect more than 660 plant species, which results in cotton Verti cillium wilt characterized as serious damage and difficult to control. Microsclerotia are the main sur vival structure of V. dahliae and primarily inoculum of Verticillium wilt in soil. It will be useful for predicting the disease level based on microsclerotium quantity from the spatial pattern and sampling method. The investigation in Yangling showed that spatial pattern of the microsclerotium was aggre gated or uniform distribution, and changing with its mean density at 0-20cm soil layers. The theo retical model for sampling microsclerotia in soil was n = 1. 467 9 （t/D）2m-126 4. If the economic threshold was given as 0.5 microsclerotia per gram soil, the Iwao＇s sequential sampling model was achieved with the maximum sampling size of 35 plots. Comparing different fixed-sample-size tech niques, we concluded that the bidiagonal technique is preferable, and the sampling size changes with the density of microsclerotia in soil.

关 键 词：大丽轮枝菌 微菌核 分布型 抽样技术 

分 类 号：S435.62[农业科学—农业昆虫与害虫防治]