低氧环境中印度谷螟危害能力的比较研究

COMPARATIVE ASSAY ON DAMAGING ABILITY OF PLODIA INTERPUNCTELLA(HBNER) IN LOW OXYGEN ENVIRONMENT

为了掌握储粮主要害虫印度谷螟低氧环境条件下的危害特性,对其进行科学防治,将水分含量12.5%的小麦以4头/kg的密度感染印度谷螟1龄幼虫,于密闭条件下调节环境氧气浓度至8%、11%、14%和21%,之后在不同时间取样检测小麦千粒重、虫蚀粒率和脂肪酸值。在氧气浓度11%以上环境中,第1龄印度谷螟幼虫感染7 d后小麦虫蚀粒率显著增加,小麦千粒重显著降低,至21 d后小麦的脂肪酸值显著增加。在氧气浓度8%条件下,至第14天时小麦的虫蚀粒率变化不显著,至21 d后其虫蚀粒率增加显著,经过42 d感染后小麦的千粒重变化不显著,经过35d感染后小麦脂肪酸值变化显著。结果表明,在11%以上低氧气环境中,印度谷螟幼虫在感染一周后即可对小麦造成明显危害。在氧气浓度8%环境中,印度谷螟幼虫的危害能力受到明显抑制,经过感染3周后小麦虫蚀粒率明显增加,经过1个月后小麦脂肪酸值明显增加,印度谷螟感染对小麦的千粒重降低影响不明显。

Knowing the damaging ability of insect pest,Plodiainterpunctella(Hiibner),is benefit to the scientific management and guidance to control atmosphere.The changes of insect damaged kernel(IDK),thousand kernel weight(TKW)and fatty acid value(FAV)of wheat infested by first star larvae of P.interpunctella was assayed which was stored under condition of 8%,11%,14%and 21%of oxygen concentration.The wheat with 12.5%of moisture content was infested by P.interpunctell in four first star larvae per kilogarm of grain.Under condition more than 11%of oxygen concentration,it was obvious going up for IDK and down for TKW after seven say infestation.And FAV was going up rapidly after 21 day damaging by the insect.Under condition of 8%of oxygen concentration,IDK was changed a little in 14 day period and going up sharply after 21 day duration.The TKW was changed not too much until 42 day test.FAV was obviously varied after 35 day infested keeping.When orygen concentration being more than 11%P.interpunctella can damage wheat distinctly in seven day infestation.The insect damage ability to wheat was inhibited obviously in environment of 11%of oxygen concentration.Under condition of 8%oxygen concentration IDK was increased obviously after three weeks.FAV was increased obviously after one month.TKW was decreased a little more than one month.