论文部分内容阅读
为了筛选出对杨尺蠖Apocheima cinerarius Erschoff蛹致病力较强的球孢白僵菌Beauveria bassiana菌株以及防治最佳时期,本研究以三个时期采于临汾市洪洞县杨树林内的杨尺蠖蛹为标本,观察其外部形态特征并解剖以了解其内部结构。然后用实验室现有的三株球孢白僵菌TST05、FDB01、SYN01进行毒力测定。结果表明:前期、中期和后期的杨尺蠖蛹外部形态特征大致相同,有复眼、触角、中胸气门、翅芽和臀棘等结构。不同时期的蛹内部结构变化很大。前期蛹虫体未发育完全,只看到直肠囊位于中央。中期蛹基本发育完全,已经分化出中肠和马氏管等结构。后期雌蛹中出现了卵。致病力测定结果表明:三株菌均能侵染杨尺蠖蛹,死亡虫体继续培养后长出白色菌丝。各时期杨尺蠖蛹的校正死亡率随时间变化曲线不相同,但是染菌4 d后,TST05菌株对蛹的校正死亡率一直保持最高的趋势。染菌8 d后,三个时期TST05菌株对杨尺蠖蛹的校正死亡率都是最高,LT50最小,与其他菌株差异显著(P<0.05)。TST05菌株对前期和中期蛹的校正死亡率较高,在70%以上,各时期间差异显著(P<0.05)。前期和中期LT50都低于5 d。球孢白僵菌TST05在杨尺蠖蛹期的地下防治中有较大的潜力,5月化蛹初期和7、8月雨季是防治的最佳时期。
In order to screen out the pathogenic Beauveria bassiana strain of Pupae of Apocheima cinerarius Erschoff and the best period of its prevention and treatment, this study was collected in three stages in the pupae of Populus simonii from Populus tomentosa in Hongdong County, Linfen City As the specimen, observe its external morphological features and anatomy to understand its internal structure. Then use the existing laboratory three Beauveria bassiana TST05, FDB01, SYN01 toxicity determination. The results showed that the external morphological features of pupae in the early, middle and late stages were roughly the same, with complex eyes, antennae, mid-chest valve, wing bud and gluteal spine. The internal structure of pupae varied greatly in different periods. Premature pupal worms are not fully developed, only to see the rectum sac located in the center. Medium pupa basic development is complete, has been divided into the midgut and Markov structure. Late female pupae appeared in the egg. The results of pathogenicity test showed that all three strains could infect Pupae pupae, and white mycelium grew after the dead worms were cultured. The corrected mortality rate of Pupae pupae in different periods varied with time, but the corrected mortality of Pupae of TST05 strain kept the highest after 4 days. After 8 d of infection, the corrected mortality rate of TST05 strain was the highest at the three periods, with the lowest LT50 and significant difference with other strains (P <0.05). The corrected mortality of TST05 strain in early and mid-term pupae was higher than 70%, with significant difference (P <0.05). The LT50 for both the early and mid-term are below 5 days. Beauveria bassiana TST05 has great potential in the underground control of pupal stage of Populus davidiana. The early pupation stage in May and the rainy season in July and August are the best time to control.