微生物有机肥对陇东烤烟的根际营养调控及其生物效应

Effects of bio-organic fertilizer on rhizosphere nutrition regulation and its biological effects

针对陇东烤烟生产中存在的因长期连作和施肥不合理引起的烟叶产量和品质下降等问题,本研究于2009年在甘肃省正宁县进行大田试验,以当地主栽烟草品种‘CV70’为试材,研究施用微生物有机肥对烤烟根际的营养调控及其生物效应,土壤理化和生物学性状的影响及其生物效应.结果表明:微生物有机肥处理(BOF)不仅显著提高了根际土壤细菌的丰富度和优势种的数量,降低了根际土壤的真菌/细菌比;而与对照(CK)相比,BOF处理也提高了根际土壤的有机质含量、有效氮和速效磷的含量.根际土壤生物学活性的改善和有效养分数量的增加促进了烤烟的生长发育,BOF处理的叶片叶绿素含量(SPAD)、叶片数和干物质量以及生育后期叶面积等指标在整个生育期内均显著高于对照(CK),为烤烟的高产优质奠定了基础.BOF处理的上、中、下部烟叶的钾含量分别比CK增加30.20%、26.30%、50.50%,烟碱含量增加了29.85%、37.64%、16.77%;BOF处理提高了烟叶的糖含量,缩小了总糖和还原糖之间的差值,使烟叶的施木克值(糖/蛋白质)趋于适宜范围.BOF处理的产量和产值分别比CK增加了23.20%和12 545元/hm2,中上等烟的比例增加了16%,产值比CK增加了12 363元/hm2.微生物通过改善根际的生物学活性,增加了有效养分含量,为烤烟的优质高产创造了良好的根际环境.

The decline in yield and quality of flue-cured tobacco caused by long-time continuous monocropping and irrational fertilization have been the serious problems in flue-cured tobacco production in east of Gansu Province.A field experiment was carried out in Zhengning County,Gansu Province in 2009 to study the biological effects of bio-organic fertilizer on rhizosphere nutrient regulation and its biological effects.The results showed that the microbial organic fertilizer treatment（BOF）not only significantly increased the richness of the rhizosphere bacteria and the number of dominant species,reduced the rhizosphere soil fungi/bacteria ratio,but also improved the quantity of rhizosphere soil organic matter,available nitrogen and available phosphorus.The improvement of the rhizosphere soil biological activity and availablenutrients amount facilitated the growth and development of the flue-cured tobacco.After applying BOF,leaf chlorophyll content（SPAD）,leaf number,dry weight and leaf area index in the later growth stage were all significantly higher than those of the control（CK）in the whole reproductive period.In the BOF treatment,potassium content of upper,middle and bottom leaves increased 30.20%,26.30% and 50.50%,respectively,compared with CK,while nicotine content increased 29.85%,29.85% and 29.85%,respectively.BOF treatment increased the sugar content of tobacco leaves,narrowed the difference between total sugar and reducing sugar,making tobacco Schmuck value（sugar/protein）tend to be the optimum scope.The yield and production value of BOF treatment increased 23.20% and 12545RMB/hm2 than CK,respectively;the proportion of superior tobacco increased by 16%,and its value was 12363RMB/hm2 more than CK.By improving the biological activities of microorganism in the rhizosphere and increasing the effective nutrient content,a favorable environment for the high yield rhizosphere of flue-cured tobacco was created.