生物有机肥对陇东烤烟生长的根际营养调控

针对陇东旱塬烤烟生产中存在的因长期连作和施肥不合理引起的产量持续下降、品质不高以及病虫害严重等问题,通过在苗床期和大田移栽期采用根际施用生物有机肥,研究了根际营养调控对苗床期烟苗的生长、代谢和对苗床土微生物数量以及对烟叶产量的影响。结果表明:苗床期施用生物有机肥成苗速度快,叶片数提前达到移栽标准,最大叶叶面积和干重分别比对照增加28.9%和68.0%,地上部和根系干重分别比对照增加了191.9%和100.0%;总根长、比根长和根尖数分别比对照增加了161.5%、30.8%和290.2%;根系总吸收面积、活跃吸收面积以及脱氢酶活性分别比对照增加了69.1%、70.2%和70.0%。苗床土中微生物总数比对照增加了36.7%,并使细菌与真菌的数量比从1.54×104∶1增加至1.84×104∶1。施用生物有机肥处理的产量和产值分别比对照增加了23.2%和46.5%,中上等烟比例增加了16个百分点,纯收入增加了12363元hm-2。

Nutrition-Regulating in Rhizosphere by Application of Bio-organic Fertilizer to the Growth and Yield of Flue-Cured Tobacco in Loess Plateau of East Gansu

Continuous mono-cropping and irrational fertilization have been the big problems that restrict the growth,yield and quality of flue-cured tobacco in Loess Plateau of East Gansu Province.In a field trial we studied the effects of bio-organic fertilizer applied in nursery plus the second application in transplanted soil on tobacco growth,metabolism,yield,economic benefits and soil microorganisms.The results showed that application of bio-organic fertilizer(T2,treatment) significantly promoted the growth,metabolism and dry matter accumulation of seedlings in the nursery period.The leaf area and dry weight of max leaf of flue-cured tobacco in T2 were increased separately by 28.9% and 68.0%,the dry weight of shoot and root were increased respectively by 191.9% and 100.0% compared with control(T1);and T2 had much more ideal root morphological parameters,such as small diameter,longer root length,bigger specific root length,and far more root tips,the total root length,specific root length and toot tips were increased by 161.5%,24.8% and 290.2%,respectively,compared with T1.Total root absorbing area,active root absorbing area and dehydrogenase in roots of T2 were increased by 69.1% and 70.20% and 70.0%,respectively.Application of bio-organic fertilizer in the rizosphere increased the numbers of microorganisms,bacteria,fungi and actinomyces in the nursery soil of T2 significantly by 36.7%,36.3%,14.3% and 45.8%,respectively,and also enhanced the ratio of bacteria/fungi from 1.54∶1 to 1.84∶1.All of the above treatments contributed to the higher yield,and economic benefits and better quality,the yield,economic benefits and net income of application of bio-organic fertilizer were increased by 23.2%,46.5% and 12363 yuan hm-2.