棉花根际促生细菌的研究进展

综述了根际促生细菌(PGPR)的概念、研究手段、基因标记技术和荧光原位杂交技术在研究棉花根际促生细菌中的应用.植物根系可以分泌各种对微生物有益的物质,吸引微生物在根际的聚集.棉花凝集素对根际促生细菌菌株的胞外多糖具有凝集作用,在棉花根际促生细菌与棉花根部相互识别过程中具有重要作用,可以利用棉花凝集素作为筛选工具筛选对棉花具有促生作用的根际促生细菌菌株.基因标记技术证明棉花根际促生细菌能高密度地定殖在棉花根部,对棉花的生长起促进作用,并能抑制某些植物病原菌及根际有害微生物.分子生物学技术在微生物生态学领域的应用促进了棉花根际促生细菌的研究和应用,可以利用棉花根际促生细菌研发微生物肥料.     

Effects of bacterial inoculant biofertilizers on growth,yield and nutrition of rice in Australia

Inoculant biofertilizer application increased fertilizer nitrogen (N) use efficiency in Vietnam in some previous field experiments. Similar results may be obtained in Australia. With this view in mind, a greenhouse experiment and two field experiments were conducted using a Vietnamese inoculant biofertilizer (BioGro) and several other plant growth promoting (PGP) bacteria. In the greenhouse trial, bacterial inoculations increased shoot and root weights of rice plants significantly. In the field experiments, particularly with Rhizobium leguminosarum, similar effects including significant differences in nitrogen uptake in vegetative matter were observed at the panicle initiation (PI) stage. However, these effects were not significant on grain yield at harvest and it is concluded that the much longer period of growth for Australian rice may allow compensation between treatments. Re-inoculation of plants at the PI stage, and lower application rates of N fertilizer in at least two splits are suggested for future field experiments.     

复合微生物菌肥对连作草莓矿质养分吸收及产量的影响

以‘达塞莱克特’草莓(Fragara ananassaDuch.‘Darselect’)为试材,研究了微生物菌肥对连作草莓矿质养分吸收和产量的影响。结果表明:菌肥处理促进了土壤有效N、P、K的转化,提高了土壤肥力,促进了草莓对N、P、K、Ca、Mg等矿质养分的吸收,显著提高了草莓产量(P<0.05)。所有处理中,以菌肥浓度为37.5 kg/hm2的处理草莓产量最高。     

复旦Ⅰ号生物制剂叶面肥对早春茶叶的施用效果研究

用复旦I号200倍、300倍、400倍三种浓度对龙井43品种茶树进行喷施,观察茶芽萌动情况,测定一芽一叶比例、百芽重及产量,结果表明复旦Ⅰ号能明显促进茶芽早发、提高一芽一叶比例和百芽重、从而提早开采和提高产量,合理喷施复旦Ⅰ号生物制剂叶面肥,对于增产效果明显。     

辣木根际土壤溶磷菌的筛选与鉴定

【目的】磷是限制辣木生产力的重要因素之一。在酸性土壤严重缺磷的华南地区,施用溶磷菌 能提高土壤中难溶态磷的有效性,促进植物生长发育,减少环境污染。【方法】以辣木根际土壤为研究对象, 分离溶磷细菌并通过透明圈法筛选和钼锑抗比色法测定,初步筛选有解磷能力的菌株。结合菌落形态特征和 16SrDNA高通量测序进一步鉴定优势溶磷菌。【结果】初步筛选到 19株具有解有机磷和 10株解无机磷能力的菌株, 对卵磷脂和磷酸钙的最大溶磷量分别为 26.95、13.48 mg/L, 溶磷量与 pH 呈负相关,但相关性不显著。进一步筛 选了优势有机和无机溶磷菌菌株各 2 株,分别鉴定为巨大芽孢杆菌和蜡样芽孢杆菌、枯草芽孢杆菌和假单胞菌。 此外,16S rDNA 高通量测序结果表明,分离的辣木根际土壤微生物溶磷菌主要为类芽孢杆菌属、贪铜菌属、杆 菌属、细杆菌属、根瘤菌属、根瘤菌等,其中芽孢杆菌属的丰度最高。【结论】分离筛选的优势溶磷菌可用于 溶磷菌肥的开发和应用,为改善辣木根系环境和提高生产力提供菌株资源。     

Effect of Incorporation and Unincorporation of Azolla Biofertilizer on the Grain Yield of Rice

Azolla pinnata R. Brown was used as a biofertilizer for rice crop in early and late wet seasons of 1985–86. Azolla as dual crop with rice increased the grain yield significantly over uninoculated control. Incorporation of Azolla increased the yield components and grain yield higher than leaving Azolla on water surface without incorporation. Azolla incorporation with 90 kg nitrogen/ha recorded the highest plant height, tiller numbers/ hill, panicles/m² and 1000 grain weight and grain yield of rice.     

Soil microbial inoculants for sustainable agriculture: Limitations and opportunities

The burgeoning global market for soil microbial inoculants for use in agriculture is being driven by pressure to increase sustainable crop production by managing pests and diseases without environmental impacts. Microbial inoculants, based predominantly on bacteria and fungi, are applied to soil as alternatives to conventional inorganic fertilizers (biofertilizers) or to carry out specific functions including biocontrol of pests and diseases (biopesticides), or for bioremediation and enhancement of soil characteristics. While some soil inoculants such as rhizobia have a long and successful history of use, others have performed inconsistently in the field and failed to live up to their promise suggested by laboratory testing. A more precise understanding of the ecology and modes of action of inoculant strains is key to optimizing their efficacy and guiding their targeted use to situations where they address key limitations to crop production. This will require greater collaboration between science disciplines, including microbiology, plant and soil science, molecular biology and agronomy. Inoculants must be produced and formulated to ensure their effective establishment in the soil and practicality of implementation alongside existing cropping practices. New approaches to strain selection and construction of beneficial microbial consortia should lead to more efficacious inoculant products. Extensive and rigorous field evaluation of inoculants under a range of soil and environmental conditions has rarely been undertaken and is urgently needed to validate emerging inoculant products and underpin successful implementation by growers, especially in a market that is largely unregulated at present.     

草菇菌渣接种固氮菌、磷溶菌进行有机堆肥的研究

以工厂化栽培杏鲍菇和草菇后的菌渣废弃物为主要原料,考察经2种固氮菌和溶磷菌强化的生物堆肥过程中60 d内菌渣堆温度、pH值、E4/E6值对堆肥的影响,堆肥过程中全氮、磷、钾和速效氮、磷、钾的动态变化情况,发现经微生物强化的堆肥与自然条件下堆肥的情况差别不大,说明该菌渣适宜进行自然发酵堆肥生产有机肥料,具有方便、经济的优势,为食用菌菌渣的生态无害化利用开辟新路,为进一步实现菌渣循环反哺农业种植奠定了基础。以期为菌渣废弃物的"综合、生态、链式、经济"利用提供科学支撑。     

Potassium sources,microorganisms and plant nutrition: Challenges and future research directions

Until recently, potassium(K) has not received considerable attention because of the general belief that soils contain ample amounts of this element. In addition, low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries. This results in various negative impacts, including preventing optimum utilization of applied nitrogen and phosphorus fertilizers. To compensate for these losses,massive use of K fertilizers in ...     

Recent advances in the chemistry of nitrogen,phosphorus and potassium as fertilizers in soil: A review

The advent of civilization has made humans dependent on plants for food and medicine, leading to the intensification of agricultural production. The intense cultivation of crops has resulted in the depletion of available nutrients from soil, thereby demanding the application of excess nutrients to soil to improve yield. Thus, mineral fertilizer discovery and application have, in many ways, contributed greatly to meeting global food demands. However, aside from the positive effects of mineral fer...