杏园脐腹小蠹空间分布型及易受害寄主生长性状研究

Spatial distribution type of Scolytus schevyrewi Semenov and the growth characters of the vulnerable host in apricot orchard

在脐腹小蠹(Scolytus schevyrewi Semenov)发生期,通过调查杏园脐腹小蠹空间分布及寄主生长性状发现:在杏园脐腹小蠹呈聚集分布,且个体间相互吸引,分布的基本成分是个体群;当种群密度<1.68头/株时,环境条件是其聚集的主因;当种群密度>4.92头/株时,脐腹小蠹的聚集习性和环境条件是脐腹小蠹聚集的主因;其为害程度与杏树新生枝条长度、直径、百叶重和叶片含水量呈显著负相关,与叶绿素含量无相关关系;不同受害程度杏树树脂分泌量呈正态分布,零星被害和持续被害杏树树脂分泌量显著大于健康和易被害致死杏树;6月平均新生枝条长度<14.85cm、直径<0.31cm、百叶重<52.40g的杏树易受害,新生枝条长度<12.70cm、直径<0.29cm、百叶重<49.36g的杏树易受害致死。

During the emergence period of Scolytus schevyrewi Semenov,the spatial distribution type of S.schevyrewi and host growth characters were studied in apricot orchards.The results showed that the spatial distribution type of S.schevyrewi was aggregative distribution,with individuals attracting each other,and the individual group was the basic component in its distribution.When the population density1.68individuals/plant,the environmental conditions were the main cause for the aggregation;when the population density4.92 individuals/plant,the environmental factors and aggregation behavior were the main cause.The damage degree of S.schevyrewi had significantly negative correlation with the length and diameter of new shoots,weight per hundred leaves and leaf water content.However,it had no correlation with chlorophyll content of apricot leaves.Resin secretion of apricot was in a normal distribution.Resin secretion of the vulnerable apricots under sporadic or continued damage was significantly greater than that of healthy and vulnerable dead apricots.The apricots with new shoot length less than 14.85 cm,new shoot diameter less than0.31 cm,and hundred-leaf weight less than52.40 g were easy to be infested by S.schevyrewi.The apricots with new shoot length less than 12.70 cm,new shoot diameter less than0.29 cm,hundred-leaf weight less than 49.36 g were easy to be infested and die.