百合生育期根际土壤微生物和酶活性的变化

Variation of Microbial Biomass and Enzyme Activities in the Rhizosphere Soil of Lily at Different Developmental Periods

在自然生长条件下,研究了不同品种百合在不同生育期根际土壤微生物种类、数量和土壤酶(过氧化氢酶、脲酶、碱性磷酸酶)活性的变化规律。结果表明:在百合生育期内,土壤微生物以细菌最多,对百合的根际效应也最敏感;其次为真菌,再次为放线菌。不同生育阶段以显蕾期根际土壤细菌和放线菌的数量最多,但显蕾期以后二者根际效应方向相反;根际土壤真菌的数量和根际效应在鳞茎充实期均达到最大。土壤脲酶活性和碱性磷酸酶活性在百合生育期内表现为先降、后升、再降的趋势,即在显蕾期形成峰值,根际效应显著,随生殖生长的推进其活性及根际效应均逐渐减弱;而过氧化氢酶活性则先上升后下降,根际效应不明显。在百合—土壤—微生物相互作用的体系中,根际土壤微生物的种类、数量和酶活性明显受到百合生长发育的影响。

The experiment was conducted to study the variation of the kinds and the number of microbial biomass and enzyme （catalase, urease, alkaline phosphatase） activities in the rhizosphere soil of different lily varieties at different developmental periods under nature conditions. The results showed that bacteria ranked first in the quantity of rhizosphere soil microorganism during the whole developmental periods and was the most sensitive to lily rhizosphere effect. Fungi was the second, and actinomycete was the third place. At flower budding period, the quantity of bacteria and actinomycete in the rhizosphere soil of lily appeared at most, but their rhizosphere effect was opposite after this period. The fungi quantity and its rhizosphere effect were great at bulb substantiating period. The activities of urease and alkaline phosphatase in the soil appeared in the trend of fall, rise and fall, and reached a peak at flower budding period with a remarkable rhizosphere effect, along with the reproductive development, the activities of the two enzymes and rhizosphere effect weakened gradually. The activity of catalase appeared in the trend of rise first and then fall, but the rhizosphere effect was not obvious. The results suggested that the microbial biomass and enzyme activities of rhizosphere soil are remarkably affected by the growth and development of lily in the interaction system of lily - soil - microorganisms.