玉米粗缩病危害动态及空间格局和抽样技术的研究

为了提高对玉米粗缩病监测预报与持续控制水平，对浙西北桐庐地区玉米粗缩病侵染循环及发病动态与空间分布格局和抽样技术的调查研究，明确了玉米粗缩病侵染循环及年际消长与发病规律，年际间粗缩病株发病率与灰飞虱种群年诱虫量呈正相关，回归式为y= 0.860605+0.071623x (R=0.9636**)。年际内夏玉米粗缩病5月底6月上旬为初病期，6月中旬至7月上旬为病情较快增长期，7月中旬达发病高峰。夏玉米发病株空间格局以聚集分布为主，在株发病率较高或较低时，聚集程度下降，或为均匀分布。根据夏玉米粗缩病病株以聚集为主的空间分布特征，田间抽样调查以单行或双行直线平行跳跃法等较宜。理论抽样模型为n=(1.96)2/D2(1.02728/m+0.10287)，序贯抽样模型为Tn=1.02728/(D2-0.10287/n)。

The Damage Dynamic, Spatial Distribution Pattern and Sampling Technique of Maize Rough Dwarf Virus Disease (MRDV) in the Northwestern of Zhejiang Province

The infection cycle, damage dynamic, spatial distribution pattern and sampling technique of maize rough dwarf virus disease （MRDV） in Tonglu County of Northwestern of Zhejiang Province were studied, in order to improve the monitoring, prediction and the sustained control system for MRDV disease. Infection cycle, annual dynamic and occurrence of MRDV disease were made clearly. The positive correlation was observed between till incidence of the virus disease and annual total amounts of small brown planthopper, Laodelpbax striatellus. The regression equation： y= 0.860605 ＋ 0.071623x （R=0.9636″）. MRDV disease of summer maize was in early infection stage from late May to early June, then in fast increase period from the middle of June to the early of July, and infection peak in the middle of July. The till spatial distribution pattern of summer maize was the assemble distribution type, when till incidence percentage was higher or lower, aggregation degree declined or uniform distribution. Based on this distribution pattern, the optimal sampling technique was single line or double line linear parallel jumping method. The theoretical sampling model was as follows： n=（1.96）2/IT（1.02728/m ＋ 0.10287）, and sequential sampling model were as follows： Tn=1.02728/ （/Y-0.10287/n）. These results provided scientific basis for sampling investigating precisely and controlling effectively MRDV disease of summer maize.