有机肥混施对烤烟根际土壤酶活性及微生物碳氮含量的影响

The Effect of Mixed Organic Fertilizers on Soil Enzyme Activities and Microbial C,N Transformation in Rhizosphere of Flue-cured Tobacco

采用盆栽试验研究了花生饼肥、猪粪及化肥混合施用对烤烟根际土壤转化酶、脲酶活性和微生物量碳、氮及腐殖酸总碳量的影响。结果表明,土壤转化酶活性高峰出现在现蕾期,而脲酶活性在团棵期最高。花生饼肥、花生饼肥+猪粪、花生饼肥+猪粪+化肥配施时土壤酶活性显著高于化肥和不施肥处理;花生饼肥+猪粪混施显著提高微生物量碳、氮含量,纯施花生饼肥最高,其次是花生饼肥与化肥配施;不同生育时期内,微生物量碳、氮含量动态变化以微生物量碳在现蕾期达到最高值,而微生物量氮高峰出现在团棵期;施用花生饼肥提高了土壤腐殖酸总碳,花生饼肥比对照、化肥处理提高了52.2%;单施猪粪比对照、单施化肥处理提高了26.1%;但饼肥+猪粪比对照、单施化肥提高143.48%。结果表明,长期过量施用化肥烤烟土壤中,通过混施一定比例不同碳氮比的猪粪与花生饼肥,不但能够调控土壤酶活性,土壤微生物量碳、氮转化,而且增加根际土壤腐殖酸含量,提高土壤肥力,有利于烤烟品质的改善。

A pot experiment was conducted to study the effects of mixed fertilizers with peanut cake, pig manure and chemical fertilizer on invertase and urease activity, microbial C, N and total C of humic acid in rhizosphere soil of flue--cured tobacco. The results showed that, the peak of invertase activity appeared in the budding stage, and urease activity is highest in the rosette stage. Soil enzyme activity in Peanut cake, peanut cake＋pig manure, pig manure＋chemical fertilizer treatments was significantly higher than that of chemical fertilizer and no fertilizer; Mixed fertilizer with peanut cake and pig manure increased microbial C, N content, and peanut cake fertilizer is highest, followed by mixed fertilizer with peanut cake and chemical fertilizer; With different growth period, in the dynamic change of microbial C, N content, micro- bial C was the highest in bud stage, and microbial N peak appeared at the rosette stage the application of peanut cake fertilizer increased the total C in soil humic acid, compared with the control, chemical fertilizer treatment, soil humic acid with peanut cake increased by 52.2% ; compared with the control, chemical fer-tilizer treatment, pig manure increased by 26.1%; but compared with control, chemical fertilizer, peanut cakeq-pig manure increased by 143.48~//oo. The results suggested that the long--term excessive use of chemical fertilizer in flue--cured tobacco soil, the mixed application of a certain proportion of pig manure and peanut cake fertilizer ratio with different carbon and nitrogen, can not only control the activity of soil enzyme, soil microbial hiomass C, N transformation, but also increased the rhizosphere soil humic acid content to improve soil fertility and the quality of flue--cured tobacco.