不同剂型联合固氮菌肥对青稞促生效应和固氮能力研究

Effect of Associative Nitrogen-fixing Biofertilizer Produced with Different Carriers on Growth and Nitrogen Fixing Ability of Hordeum vulgare var. nudum Hook.f.

利用联合固氮菌(Associative nitrogen-fixing bacteria)制作菌肥,设7个处理:CK1(基质对照,泥炭拌种)、CK2(半量15N尿素)、1N(全量氮肥)、1/2NL(半量15N尿素+液态菌肥)、NL(液态菌肥)、1/2NS(半量15N尿素+固态菌肥)、NS(固态菌肥),通过温室盆栽实验,利用15N稳定性同位素稀释法,测定其对青稞(Hordeum vulgarevar.nudumHook.f.)生长及固氮能力的影响。结果表明,本研究研制的联合固氮菌肥符合《农用微生物菌剂》质量标准(GB 20287-2006),且固体菌肥的有效活菌数在检测的各个时期都高于液体菌肥。对于株高、地上生物量、地下生物量、根冠比来说,联合固氮菌肥与半量氮肥(110 kg.hm-2)配合施用,表现出与全量氮肥相近的促生效果,即可节约近一半的氮肥用量(110 kg.hm-2);固体菌肥和液体菌肥的固氮百分率和固氮量分别为17.44%、14.03%和22.87 kg.hm-2、21.29 kg.hm-2。并且,固体菌肥对青稞生长的促进作用优于液体菌肥。

The associative nitrogen-fixing biofertilizer as a new green fertilizer has been paid more attention recently.The effect of biofertilizer produced with associative nitrogen-fixing bacteria and different carriers（LB liquid culture medium and peat） on the growth and nitrogen fixing ability of Hordeum vulgare var.nudum Hook.f.was studied through pot experiment in greenhouse.15N isotope dilution method was employed with 7 treatments,including CK1（peat）,CK2（half application rate of 15N labeled urea）,1N（whole application rate of urea）,1/2NL（half application rate of 15N labeled urea＋liquid biofertilizer）,NL（liquid biofertilizer）,1/2NS（half application rate of 15N labeled urea＋peat biofertilizer）,and NS（peat biofertilizer）.The results indicate that the associative nitrogen-fixing biofertilizer accorded with the quality criterion of agricultural microbial fertilizer of China（GB 20287-2006） and the number of effective bacteria in peat biofertilizer was much higher than liquid biofertilizer.The effect of the biofertilizer added with half application rate of chemical nitrogen fertilizer（110 kg·hm-2） on plant height,aboveground biomass,underground biomass,and root/shoot ratio was similar to the whole application rate of chemical nitrogen fertilizer（220 kg·hm-2）,suggesting that the half chemical nitrogen fertilizer could be saved.The nitrogen fixing percentage and amount of peat biofertilizer and liquid biofertilizer were 17.44%,14.03% and 22.87 kg·hm-2,21.29 kg·hm-2,respectively.The peat biofertilizer had better growth performing effect than liquid biofertilizer.