不同光照条件下4种满江红(Azolla)品系体内多酚氧化酶活性的变化

Variation in in vivo Polyphenol Oxidase Activity of Four Azolla Strains Under Different Illumination Conditions

在生物学观察测定基础上，引入生化测定方法探讨不同光照条件下卡洲满江红３００１ 、小叶满江红４０１８ 、杂交萍９０４６ 和回交萍ＭＨ３１ 四个红萍品系体内多酚氧化酶（ＰＰＯ） 活性变化趋势。结果表明，光照影响各满江红品系的生长速率与抗霉腐病能力，随着光照强度减弱，各品系的生长速率和抗霉腐病能力都下降。在低光下，供试的满江红品系生物量与体内ＰＰＯ 活性的相关性显著（ｒ＝ ０ ．９５６０） 。低光下满江红各品系生长速率、抗霉腐病能力和体内ＰＰＯ 活性的从高到低依次为卡洲满江红３００１ 、杂交萍９０４６ 、小叶满江红４０１８ 和回交萍ＭＨ３１ 。从生理、生化角度讨论了满江红耐荫性与体内多酚氧化酶活性的关系。

Shade tolerance is an important physiological index for the selection of Azolla strains. A biochemical determination was made in this study to probe into the variation in the in vivopolyphenol oxidase (PPO) activity of four Azolla strains, A. carolilnana 3001, A. microphylla 4018, hybrid Azolla 90 4 6 and backcrossed Azolla MH3 1 under different illumination conditions. The results showed that illumination affected the growth rate and resistance of Azolla against black rot disease, both of which were lower under weak light (Tables 1,2).Following the decrease of illumination from 420 to 105 μmol m -2 s -1 ,the PPO activities of four tested Azolla strains increased (Fig.1). Under weak illumination, significant correlation ( r = 0.9560 ) was found between Azolla biomass of tested strains and their in vivo PPO activity. A. caroliniana 3001 had the highest PPO activity and biomass, backcrossed Azolla MH3 1 had the lowest PPO activity and biomass (Table 3). The same tendency has been observed in the experiment on the induction of black rot disease. The order of black rot resistance of these tested strains was A. caroliniana 3001> hybrid Azolla90 4 6> A. microphilla 4018 > backcrossed Azolla MH3 1. The relationship between shade tolerance of Azolla and the in vivo PPO activity has been discussed (Fig.2).