烟蚜为害的经济损失研究

A STUDY ON EFFECTS OF MYZUS PERSICAE (SULZER)DAMAGE UPON ECONOMIC LOSSES OF FLUECURED TOBACCO

在陕西渭北烟草种植区迁飞到烟田的蚜虫有６种，但只有桃蚜Ｍｙｚｕｓｐｅｒｓｉｃａｅ（Ｓｕｌｚｅｒ）能够建立种群，造成为害。从烟草旺长开始，按烟株上蚜色和蚜虫分泌蜜露，引起霉菌滋生，污染叶面积的比例分为０、Ⅰ、Ⅱ、Ⅲ、Ⅳ级。以未受蚜害的０级为对照，受蚜害的Ⅰ、Ⅱ、Ⅲ、Ⅳ级的中上等烟下降分别为６．９３％、１３．０５％、２８．５１％和３０．９４％，经济损失率分别为９．８６％、２３．８１％、３６．１２％和３９．５９％。化学成分分析表明：Ⅰ、Ⅱ、Ⅲ和Ⅳ级烟叶的烟碱含量分别降低１０．６１％、１９．２９％、１０．６１％和２５．４０％，还原搪分别降低１５．０４％、１９．２３％、４０．９８％和４４．８６％，蛋白质含量分别提高１６．１７％、３１．７７％、３７．０２％和３８．７２％。这就表明桃蚜为害既影响烤烟的外观质量、又影响内在品质。１头蚜虫经济损失率＝０．０６９５％。

here are 6 species of aphid flying and migrating to tobacco plants in the re-gion of cultured tobacco in the north of Wei River, Shaanxi Province, but onlyMyzus perticae (Sulzer) can do damage to tobacco. Tobacco plants are divided intograde 0, Ⅰ, Ⅱ, Ⅲ and Ⅳ according to the aphid quantity per plant in the periodof its serious damage, and leaf area polluted by mould caused by honey dew secre-ted by the aphid in the period of tobacco ripening. Compared with grade 0 notinjured by the aphid, the mid-and high-grade tobacco leaves in grade Ⅰ,Ⅱ,Ⅲ andⅣ injured by the aphid are reduced by 6.93 %, 13.05%, 28.51 % and 30.94 % respec-tively. The economic losses caused by the aphid are 9.86 %, 23.81 %, 36.12 % and39.59%respectively. The analyses of chemical composition indicate that nicotineof the leaves in grade Ⅰ,Ⅱ, Ⅲ and tV is reduced by 10.61 %, 19.29%, 10.61 % and25.40%, reducing sugar is reduced by 15.04 %, 19.23 %, 40.78% and 44.86.%, andprotein are increased by 16.17%, 31.77 %, 37.02% and 38.72 % respectively. Thescshow that both the external and internal qualities of the flue-cured tobacco leavesare influenced by the aphid injury. The economic loss of one aphid is about 0.0695%.