不同家蚕品种血淋巴总SOD活力的差异及与生命力和产茧量性状的相关性

超氧化物歧化酶(SOD)是生物体内的一种重要氧自由基清除剂,并在一定程度上影响到生物体的抗逆能力。通过调查分析家蚕5龄幼虫血淋巴总SOD活力在不同地理系统、不同化性品种间和不同温湿度饲养条件下的差异,探讨通过测定5龄幼虫血淋巴总SOD活力,选择家蚕抗性品种育种材料的可行性。结果表明:常温下中系二化性品种5龄幼虫血淋巴的总SOD活力显著高于日系二化性品种和多化性品种;32℃高温、RH 95%处理一定时间后中系二化性普通品种和耐高温高湿品系总SOD活力显著升高,日系二化性普通品种和耐高温高湿品系则显著下降,但所有供试品种在35℃高温、RH 95%处理一定时间后血淋巴总SOD活力都显著低于常温常湿组。对5龄幼虫血淋巴的总SOD活力与幼虫生命率和虫蛹率的相关性统计分析表明二者之间呈显著正相关,而与茧层率之间无显著相关性。研究结果提示,5龄幼虫血淋巴总SOD活力可作为家蚕抗性育种材料选择的生化指标之一。

Differences of Total SOD Activity in Hemolymph of Different Bombyx mori Varieties and Its Correlation with Vitality and Cocoon Yield Traits

Superoxide dismutase(SOD) is an important oxygen free radical scavenger of organisms and is to some extent related to organismal resistance against adverse environment.In order to discuss the feasibility of selecting materials for breeding resistant silkworm(Bombyx mori) varieties through determining the total SOD activity in hemolymph of the 5th instar larvae,the differences of total SOD activity in hemolymph of the 5th instar larvae between silkworm varieties belonging to different geographical systems,having different voltinisms and being reared under different temperatures and humidities were investigated.The results showed that the total SOD activity in hemolymph from the 5th instar larvae of bivoltine silkworm varieties of Chinese strain under normal temperature was significantly higher than that from bivoltine varieties of Japanese strain and that from ployvoltine varieties.After being treated for a certain period under 32 ℃ and 95% RH(relative humidity),the total SOD activity of normal variety and high temperature and high humidity resistant varieties of Chinese strain increased significantly,while those of Japanese strain decreased significantly.But the total SOD activity of all tested varieties after treatment under 35 ℃ and 95% RH were significantly lower than that under the normal temperature and humidity.Correlation analysis showed that the total SOD activity in hemolymph of the 5th instar larvae had significant positive correlation with the larval survival rate and larva-pupa rate.No significant correlation was found between the total SOD activity and cocoon shell rate.The results suggest that the total SOD activity in hemolymph of the 5th instar larvae can be used as one of the biochemical indexes to select materials for breeding resistant silkworm varieties.