Carrier-based and liquid bioinoculants of Azotobacter and PSB saved chemical fertilizers in wheat (Triticum aestivum L.) and enhanced soil biological properties in Mollisols

Abstract

The increasing cost and imbalanced use of chemical fertilizers in wheat (Triticum aestivum L.) stressed the need to explore the potential of bioinoculants of Azotobacter and PSB for saving fertilizer N and P. Field experiments conducted for two years in a Mollisol at Pantnagar revealed maximum plant height, grain and straw yields and nutrient uptake by wheat with application of 100% NP. However, soil application of carrier-based biofertilizer at 10?kg?ha^?1 and liquid-based biofertilizers at 625 and 1250?mL?ha^?1 rates in combination of 75% NP were at par with 100% NP by recording significantly more mean plant height at different intervals, grain yield, by 10.9, 10.5 and 10.8%, and straw yield, by 8.6, 8.2 and 9.1%, over 75% NP, respectively. These treatments also accumulated significantly more N, P and K in plant at different age and; grain and straw. An application of liquid biofertilizer at 1250?mL?ha^?1 with 75% NP gave maximum population of Azotobacter and PSB, microbial biomass C and activities of acid and alkaline phosphatase in soil at different crop age. The carrier and liquid formulations of the biofertilizers were comparable in their performance. Irrespective of formulation and doses, application of biofertilizers in soil was found better than seed treatment for different recorded parameters. An application of 625?mL?ha^?1 liquid biofertilizers in soil with 75% NP was found optimum for the growth, yield and nutrients uptake and soil biological properties.     

配施木霉微生物肥对连作黄瓜的影响

研究减量化肥与哈茨木霉SQR-T037微生物肥配施对盆栽黄瓜产量、品质及土壤有效养分和可培养微生物数量的影响。试验以当地农民惯用化肥施用量的100%作为对照处理(CF),75%的农民惯用化肥量配施普通有机肥(OF)或木霉SQR-T037微生物肥(BF)作处理进行连续盆栽试验。结果表明,75%的农民惯用化肥量配施木霉微生物肥BF与100%的化肥处理CF产量相等且后期有所增产,相对配施普通有机肥处理OF则产量显著提高,同时黄瓜果实中硝酸盐含量降低45%以上,维生素C含量明显增加。此外,BF处理能有效改善土壤养分供应状况,有效磷和速效钾含量明显高于对照CF和OF处理,并显著提高黄瓜根际土壤细菌、有益菌种木霉的数量,维持放线菌数量稳定,且在施用第三季后显著减少真菌数量。因此,减少25%的化肥并配施一定量的木霉微生物肥(50g株~(-1)),不仅能保证黄瓜稳产,还能显著改善黄瓜果实品质,促进土壤中养分的高效利用,节约施肥成本,促进农业可持续发展。     

藻类在农业面源污染防控中的应用

根据2010年第一次全国污染源普查公报,农业面源污染已经成为我国地表水总氮(TN)、总磷(TP)等污染物的首要污染源。藻类广泛存在于包括稻田在内的各类水生态系统中,其生长需要消耗大量的N、P营养物质,而且藻类回收后还可用于生产生物燃料、生物肥料、土壤改良剂等,因此,利用藻类同化吸收水体中的养分可以实现农业面源污染物拦截净化和养分循环再利用双重目的。基于藻类生长特性,本文探讨了以藻类作用为主的稻田藻类固氮减磷、多营养级综合养殖系统、固着藻类沟渠净水系统及高效藻类塘等生态技术模式,并对各类技术模式的主要应用条件进行了深入比较和分析,以期为农业面源污染治理技术提供理论基础。     

Responses of Saline Soil Properties and Cotton Growth to Different Organic Amendments

Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments (e.g., cattle dung, vermicompost, biofertilizer) and earthworm inoculations (Eisenia fetida) on saline soils and cotton growth were investigated during 1 year of cotton cultivation. Compared to the control (applied with inorganic NPK fertilizer), applying organic amendments improved soil physicochemical properties. Biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.     

钾肥与生物有机肥配施防治香蕉枯萎病效果初探

通过盆栽试验研究了生物有机肥与氯化钾和硫酸钾配施防治香蕉枯萎病的效果。试验结果表明,两种肥料配施促进了香蕉苗生长,降低了香蕉枯萎病病情指数,提高了防病效果,生物有机肥与KCl和K2SO4配施防病效果比单施生物有机肥分别高60%和90%。利用T-RFLP分析土壤细菌DNA多样性,生物有机肥与钾肥配施提高了细菌三个遗传多样性指数,增加了土壤中芽胞杆菌种类。FAME分析也发现生物有机肥以及与钾肥配施促进革兰氏阳性细菌和放线菌繁殖,抑制革兰氏阴性细菌和真菌生长。生物有机肥与钾肥配施,优势互补,改善了土壤微生物群落结构,有利于提高防病效果。     

沼液微生物菌肥对设施番茄植株生长及土壤环境的影响

[目的]为改善设施农业条件下土壤肥力状况,提高设施农业产量。[方法]在银川市贺兰地区开展田间试验,分析沼液复合微生物菌肥、灭菌沼液肥、常规施肥对设施番茄株高、茎粗、叶片数等生长指标及土壤养分含量的影响。[结果]相对于对照处理,在番茄初花期沼液复合微生物菌肥,使得株高、茎粗、叶片数的增幅为32.2%~50.7%,在初果期增幅则为23.3%~46.1%;土壤有机质含量比对照提高了56.9%,全氮和全磷含量也稳步增加;而常规施肥相对于沼液复合微生物菌肥,土壤速效磷和速效钾含量大量增加(增幅分别为203.0%和50.0%),容易造成土壤养分的淋失。沼液复合微生物菌肥条件下,番茄生长指标与土壤碱解氮、有机质含量极显著正相关;而常规施肥条件下番茄生长指标与土壤养分间相关性不显著。[结论]设施种植条件下,沼液复合微生物菌肥相对于其他肥料类型更有助于番茄植株生长和土壤肥力的提高。     

Multiphasic characterization of a plant growth promoting bacterial strain,Burkholderia sp.7016 and its effect on tomato growth in the field

Aiming at searching for plant growth promoting rhizobacteria(PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identified as Burkholderia sp. based on 16 S r DNA sequence analysis, as well as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid(ACC) deaminase activity and phosphate solubilizing ability; inhibited the growth of Sclerotinia sclerotiorum, Gibberella zeae and Verticillium dahliae; and produced small quantities of indole acetic acid(IAA). In green house experiments, significant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16 S r DNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the field experiments, Burkholderia sp. 7016 enhanced the tomato yield and significantly promoted activities of soil urease, phosphatase, sucrase, and catalase. All these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer.     

颗粒生物肥料在油菜上的应用效果研究

采用裂区试验设计,通过大棚油菜盆栽试验,采用颗粒生物肥料与鸡粪的不同配比,对颗粒生物肥料的肥效进行初步探讨。结果表明,单独或混合施用颗粒生物肥料和鸡粪,对盆栽油菜土壤养分及产量、品质的提高均有明显的促进作用,其中以颗粒生物肥料与鸡粪配施的效果最为明显,其配施比例为颗粒生物肥料5 g/kg+鸡粪10 g/kg时,颗粒生物肥料的肥效释放效果最佳。其中,土壤有机质、碱解氮、速效P含量分别为11.70 g/kg,30.13 mg/kg,26.87 mg/kg,油菜Vc、还原糖、硝酸盐分别为153 mg/kg,10.25 mg/g,468.50mg/kg,产量为576.0 g/盆。     

不同剂型联合固氮菌肥对青稞促生效应和固氮能力研究

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.nudum Hook.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(GB20287-2006),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(110kg·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(110kg·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。     

生物有机肥对甘蔗产量及土壤的影响

研制了新型生物有机肥A、B,并对其在甘蔗施用效果和土壤肥力的影响进行了初探。结果表明,新型生物有机肥可明显改善甘蔗农艺性状、提高产量。施用新型生物有机肥A、B,其甘蔗产量分别比施用同等量的常规复合肥提高7.06%和10.76%,差异达显著水平。同时,施用该新型生物有机肥,土壤肥力得到明显改善。施用生物有机肥后90 d,土壤中的有机质,碱解N、速效P、速效K分别比对照提高了128.40%、17.65%、63.16%和36.84%。