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1.
花生品种间根瘤量的变化有明显的差异,大粒种大于小粒种。特异固氮酶活性,品种间差异不显著,小粒种略高于大粒种,全生育期固氮酶活性出现两次高峰,与单株根瘤量的增长相一致。氮素种肥能抑制根瘤数和固氮酶活性,其抑制程度与氮肥量呈正相关,抑制时间发生在生育前期。固氮活性与籽粒蛋白质含量呈显著的正相关。  相似文献   
2.
杨凯元  黄臣  高鹏  梁银萍  韩玲娟  赵祥 《草地学报》2022,30(12):3241-3252
根瘤内生解磷菌具有促进豆科植物结瘤固氮,提高植物抗逆性等作用。本研究以‘晋农1号’达乌里胡枝子(Lespedeza daurica ‘Jinnong NO.1’)为试验材料,采用“划线法”分离其根瘤内生菌,筛选具有解磷能力的菌株,测定其解磷能力,并对其抗逆和促生特性进行研究。结果表明:达乌里胡枝子根瘤中共分离出88株内生菌,其中11株具有解磷能力;TG41,TG43,TG47和TG68解有机磷量为0.73~1.29μg·mL-1,TG47和TG68解无机磷量为72.97和1.29μg·mL-1,为有效解磷菌;经鉴定,TG41和TG43为Bacillus zanthoxyli,TG47为Phyllobacterium zundukense,TG68为Pantoea agglomerans;TG41,TG43和TG68在盐浓度0.01%~9.00%和pH4~pH12条件下均可生长;4株菌不耐高温,TG47和TG68能在4℃生长;TG41,TG43和TG68能分泌铁载体和有机酸。综上,达乌里胡枝子根瘤中存在丰富的内生菌,部分具有解磷功能、抗逆和促生潜力,可用于研发适合黄土高原地区胡枝子建植的根瘤微生物复合菌剂。  相似文献   
3.
The relationship between soil acidity and polyamine (putrescine, spermidine, spermine) concentrations in roots was evaluated and compared to (1) nodule numbers in common beans and (2) tannin concentrations in roots. Six Phaseolus vulgaris cultivars were grown in pots in a greenhouse in soil at pH 4.5 or 5.5 and inoculated with Rhizobium leguminosarum bv. phaseoli strains. At pH 4.5 nodule numbers were strongly reduced but polyamine concentrations were 50% higher than at pH 5.5. At both pH levels putrescine and spermidine were the dominant polyamines, while the concentration of spermine was less than half of the other two. There was also a cultivar effect on the polyamine concentration, but this was much less pronounced than the pH effect. By 22 days after planting the uninoculated control plants had about 13% lower levels of polyamines than the inoculated plants. The concentrations of putrescine, spermidine, and spermine were negatively correlated with nodule numbers, but positively correlated with the root tannin content. There were no significant correlations with either root or plant dry weight.  相似文献   
4.
This study tested the competitive ability of three locally isolated Cyclopia rhizobia and strain PPRICI3, the strain currently recommended for the cultivation of Cyclopia, a tea-producing legume. Under sterile glasshouse conditions, the three locally isolated strains were equally competitive with strain PPRICI3. In field soils, the inoculant strains were largely outcompeted by native rhizobia present in the soil, although nodule occupancy was higher in nodules growing close to the root crown (the original inoculation area). In glasshouse experiments using field soil, the test strains again performed poorly, gaining less than 6% nodule occupancy in the one soil type. The presence of Cyclopia-compatible rhizobia in field soils, together with the poor competitive ability of inoculant strains, resulted in inoculation having no effect on Cyclopia yield, nodule number or nodule mass. The native rhizobial population did not only effectively nodulate uninoculated control plants, they also out-competed introduced strains for nodule occupancy in inoculated plants. Nonetheless, the Cyclopia produced high crop yields, possibly due to an adequate supply of soil N.  相似文献   
5.
Inoculation of beans (Phaseolus vulgaris L.) with strains of R. tropici IIB and R. etli resulted in the disappearance of the R. tropici IIB stains from the nodule population and their replacement by other (non R. tropici IIB) bean symbionts (Vlassak et al. 1996). Coinoculation studies in monoxenic conditions and in soil core microcosms with plants harvested at two different growth stages indicated that the inoculated R. tropici IIB strains CIAT899 and F98.5 possess a good intrinsic competitiveness which declines, however, at a later plant growth stage and in soil conditions. The poor saprophytic competence of R. tropici IIB strain CIAT899 was further demonstrated by its poor survival in soil core microcosms after bean harvest. Strains were isolated from the field plots with a 3-year bean-planting history, characterized and evaluated for their competitiveness against R. tropici IIB strain CIAT899. Isolates from field plots, which had been repeatedly inoculated with R. tropici IIB strain CIAT899, showed a higher nodule occupancy compared to R. tropici IIB strain CIAT899, and this higher competitiveness exhibited by the field isolates might be an additional reason for the poor performance of R. tropici IIB strain CIAT899 in the field study. Plots with and without a history of bean production revealed after 3-year bean cultivation an almost totally different population that also significantly differed in competitiveness. Received: 12 February 1996  相似文献   
6.
A plant growth-promoting rhizobacterium (Azospirillum brasilense Sp7) and a bio-control fungus, which can solubilize insoluble phosphorus (Trichoderma harzianum Rifai 1295-22), were evaluated for their single and combined effects on dry bean (Phaseolus vulgaris) and wheat (Triticum aestivum L.) grown in soil. A pot experiment with bean and a field experiment with both bean and wheat were established. In contrast to single inoculation of Trichoderma, the single inoculation of Azospirillum and the double inoculation did not significantly (P >0.05) increase nodule numbers and nodule mass at 45 days after planting in pot grown beans. However, the Azospirillum inoculation with supplementary phosphorus significantly (P <0.05) increased nodule mass. There were no significant (P >0.05) differences among the inoculation treatments for plant dry weight, total plant nitrogen, and total plant phosphorus at 45 days after planting in both pot and field experiments with bean. However, the combined inoculation and rock phosphate application at 1 Mg ha–1 significantly (P <0.05) increased bean seed yield, total seed nitrogen and phosphorus in the bean field trial. This treatment more than doubled the mentioned properties compared to the control. The microbial inoculations, with the exception of the combined inoculation, significantly (P <0.05) increased total seed nitrogen, but never affected seed yield in the wheat field trial (P >0.05). The combined inoculation improves many plant and yield parameters and, therefore, has some advantages over single inoculation provided that rock phosphate was supplied at an amount not exceeding 1 Mg ha–1. Higher rock phosphate application rates decreased many plant and yield parameters in our study.This work was carried out at Gaziosmanpaa University, Tokat, Turkey.  相似文献   
7.
盆栽试验结果表明,单独根瘤菌拌种虽可增加花生单株根瘤的数量和重量,提高叶片含氮量,但荚果增产并不显著;根瘤菌拌种+有机肥或钼肥处理,不仅可增加单株根瘤的数量和重量,提高花生叶片含氮量,同时植株高度、分枝数、单株结果数、饱果率及总生物产量等都有不同程度的提高,荚果增产显著。根瘤菌与有机肥或钼肥存在较大的交互效应,生产中使用根瘤菌拌种时,应注意适当增施有机肥和钼肥。  相似文献   
8.
《Plant Production Science》2013,16(1):112-121
Abstract

The Supernodulating Soybean Cultivar Sakukei 4 Was Previously Characterized By Its Superior Capabilities of Nitrogen (N) Fixation and Photosynthesis, and Was Expected To Be High Yielding. Since The N Absorption By Sakukei 4 Is Largely Dependent On N Fixation, It May Be Strongly Affected By Waterlogging During The Vegetative Stage, Which Occurs Frequently in Major Soybean Producing Areas. in This Study, We investigated The Reduced Growth and Yield Resulting From Waterlogging DuringVegetative Stage and The Subsequent Recovery in Sakukei 4, in Comparison With Those in The Normally-Nodulating Cultivar Enrei and Non-Nodulating Genotype En1282. Under The Field Conditions, The Reduction of Growth and Yield By Waterlogging Was Greatest in En1282 Among The Three Genotypes, indicating That Capability of N Fixation Is Essential For The Recovery From Waterlogging-induced injury. The Waterlogging-induced Yield Reduction in Sakukei 4 Resembled That in Enrei, Although Growth Reduction Was Greater in Sakukei 4 Than in Enrei. Irrespective of Cultivar, The Yield Was Associated More Closely With The Crop Growth Rate (Cgr) During The Post-Treatment Stage Than With That During The Waterlogging Treatment. in The Pot Experiments, Yields Positively Correlated With Both Above- and Underground Plant Parts Irrespective of Cultivar, Not Significantly, But Significantly With Root Dry Weights in Enrei and With Nodule Dry Weights in Sakukei 4. These Results indicate That Sakukei 4 Exhibits A Marked Decrease in Dry Matter Production By Waterlogging, But Yield Decrease Is Compensated To A Level Similar To That of Enrei Because of Its Enhanced Nodule Growth During The Recovery Stage.  相似文献   
9.
Summary

This paper summarizes the conception and development of microbial fertilizers and inoculants in China that are used to improve soil quality and the growth, yield and protection of crops. The results presented show the relative effects of these microbial products applied singly or with chemical fertilizers on soil fertility, crop yield and protection. The paper discusses current trends in the development and use of microbial fertilizers in China and suggests areas of high priority research.  相似文献   
10.
本试验为寻求垄沟集雨种植适宜覆盖材料,探究生物炭土壤结皮增产机理,以传统平作为对照,研究了不同垄覆盖材料和不同沟垄比对红豆草(Onobrychis viciifolia Scop)根系特征值(根干重、根长、根表面积、根体积)和根瘤特征值(根瘤数量和重量)的影响。结果表明,红豆草根系和根瘤集中分布于表层(0~20 cm)土壤,红豆草根系特征值和根瘤特征值随垄宽度增加而增加,随土壤深度增加而减少,沟边的根系和根瘤特征值明显大于沟中。与对照相比,土垄、玉米秸秆炭垄和牛粪炭垄的红豆草总根干重分别增加18%,113%和56%,总根瘤数分别增加180%,860%和313%,总根瘤重分别增加86%,489%和198%;但红豆草总根长分别减少37%,33%和27%,总根表面积分别减少53%,27%和44%,总根体积分别减少54%,14%和34%。适宜土壤湿度促进红豆草根干重、根瘤数量和根瘤重量提高;适宜土壤水分胁迫有利于红豆草根长、根表面积和根体积增加。  相似文献   
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