BM秸秆腐熟剂在小麦上的应用效果

在大田条件下,研究了BM秸秆腐熟剂对还田玉米秸秆腐熟程度和小麦生长发育及产量的影响,结果表明:施用BM秸秆腐熟剂与不施用BM秸秆腐熟剂相比,还田秸秆提早30d腐熟,且小麦植株生长健壮,分蘖多,千粒重提高.最佳处理方法是在施用配方肥的基础上(525 kg/hm2)进行秸秆还田并加施BM秸秆腐熟剂30 kg/hm2,与在习...     

Effect of Inoculant Rate on Nodulation and Various Agronomic Traits of Soybean

In a soil lacking indigenous Bradyrhizobium japonicum , soybean ( Glycine max [L.] Merr.) nodulation depends upon the number of rhizobia applied with the inoculum. This field study reports the effect of different rates of applied rhizobia on nodulation, dry matter and nitrogen content in soybean in a Mediterranean soil lacking B. japonicum.
Treatments included six rates of B. japonicum , ranging from 2.5 × 10⁴ to 6.075 × 10⁶ rhizobia cells per seed applied to the seed as peat inoculant at planting, 100 kg N ha⁻¹ and an uninoculated control. The experiment was conducted in an Entisol soil. Regression analysis showed linear relationship between the rate of applied rhizobia and the number of the nodules per plant or the dry weight per nodule. In early stages of development (32 and 68 days after planting) plant dry weight was not affected by inoculation rate. At harvest a rate of 7.5 × 10⁴ rhizobia cells per seed was necessary for maximum total and stover dry weight. A higher rate, 6.75 × 10⁵ rhizobia cells per seed, was required to obtain maximum grain yield, total N content in plant tops and grain N content. Grain percentage N was increased up to 2.025 × 10⁶ rhizobia cells per seed. Nitrogen application increased grain yield, total N content and grain N content at the same level as the lower inoculation rate.     

腐熟剂在秸秆还田中的应用效果及施用技术

推广水稻秸秆还田施用秸秆腐熟剂,可以增加土壤有机质含量,提高作物产量,减少环境污染。总结了秸秆腐熟剂的施用技术。     

双孢蘑菇菌渣堆肥及其肥效的研究

为了促进农业废弃物资源的循环利用,以双孢蘑菇菌渣为研究对象,通过菌渣堆肥中添加发酵剂或鸡粪的处理,分析了堆肥过程中各个时期不同处理的温度、pH值、EC值、全氮、全磷和全钾的变化趋势,并用腐熟后的堆肥菌渣进行了水稻肥效试验。结果表明,双孢蘑菇菌渣堆制过程中加入发酵菌剂可快速提高堆体温度,与未加发酵菌剂的堆肥处理A相比,在堆肥中加入发酵菌剂后,堆肥中全氮、全钾和速效钾的含量增加量分别为处理A的3倍、1.43倍和2.67倍;菌渣堆肥结束后,处理A,处理B和处理C速效磷含量分别比发酵前增加了54.5%、38.5%和58.3%。菌渣肥水稻田间试验表明,双孢蘑菇菌渣有机肥能够促进水稻增产,菌渣堆肥增产效果优于不发酵菌渣,而加于菌剂处理的堆肥增产效果最佳,按400kg·667m-2施肥,水稻空瘪粒数少,穗粒饱满,水稻单产553.37kg·667m-2,与当地常规施肥方式相比较增产20.55%,与不施肥处理相比较增产44.18%。     

微生物菌剂对设施辣椒秸秆原位堆肥土壤理化性质及细菌群落的影响

为明确微生物菌剂对设施废弃秸秆参与原位堆肥的影响,以辣椒秸秆为研究对象,利用实验室常规化学分析方法,测定堆肥理化性质,并通过16srDNA高通量测序技术分析堆肥过程细菌群落。结果表明：外源微生物菌剂可显著提高堆肥期间土壤温度,提高电导率值,促进总氮的固定,有效减少堆肥中期氮素损失。不同发酵时期细菌优势菌种不同,变形菌门（Proteobacteria）、厚壁菌门（Firmicutes）、酸杆菌门（Acidobacteria）、绿弯菌门（Chloroflexi）、芽单胞菌门（Gemmatimonadetes）、拟杆菌门（Bacteroidetes）、放线菌门（Actinobacteria）和异常球菌-栖热菌门（Deinococcus-Thermus）是辣椒秸秆原位堆肥过程在门水平优势细菌。克雷伯氏菌属（Klebsiella）,芽孢杆菌属（Bacillus）,不动杆菌属（Acinetobacter）和假单孢菌属（Pseudomonas）是属水平优势细菌。微生物菌剂对细菌群落结构的影响主要体现在堆肥升温期和降温期。添加300kg/hm2微生物菌剂处理堆肥最高温度比对照提高1.95℃,和堆肥前相...     

复合菌剂对玉米秸秆的降解及土壤生态特性的影响

还田玉米秸秆降解过程中施加含有植物内生真菌的复合菌剂,在盆栽条件下研究了该菌剂对还田秸秆的降解作用,对土壤生态以及后季作物小麦生长的影响。结果表明:添加复合菌剂能够促进玉米秸秆的降解,在前30 d时效果最显著,尤其是木质素的降解,两种复合菌剂处理组木质素降解率分别比市购秸秆腐熟剂高117.36%和242.70%;施用菌剂会显著增加小麦生长早期土壤蔗糖酶、脲酶和纤维素酶的活性,增加小麦生长早期土壤微生物数量;改善土壤理化性质,提高小麦成熟后土壤中的全氮、全钾、碱解氮和速效钾的含量;显著改善小麦生长状况,小麦返青拔节期叶片叶绿素含量显著增加,收获小麦单株生物量和单株产量也有所增加。     

Structure and diversity among rhizobial strains, populations and communities-a review

Published studies of rhizobial populations, communities and other strain collections were analysed to identify trends in strain richness, strain dominance and genetic diversity within and between locations. For individual populations and communities, strain richness indices were calculated by dividing the number of strain types identified by the number of isolates recovered. Where possible, strain dominance (the proportion of rhizobial isolates represented by each strain type) was also calculated. Analysis of the genetic diversity of populations, communities and rhizobial strain collections originating from diverse legume hosts and locations, was confined to studies using multilocus enzyme electrophoresis (MLEE) so that diversity could be compared on the basis of published H values. Strain richness indices were highly variable (0.02-0.94) and were influenced by both the discriminatory power of the strain typing method and the type and number of legume species used to recover rhizobia from soil. The strain richness of populations recovered either directly from soil, or from the nodules of trap hosts inoculated with the same soil, was similar. Because the arithmetic relationship between the number of strain types and number of isolates varies between different populations and communities, strain richness curves are proposed as the most appropriate method for reporting rhizobial structural diversity. Comparison of over 50 rhizobial populations and communities from published studies showed that strain dominance patterns in nodules were often similar. Typically, a single strain type occupies more than 30% of nodules with the majority of strain types being recovered at low frequency (∼75% of published populations and communities). Rhizobial populations and communities characterised by MLEE varied in their genetic diversity, with H values ranging from 0.06 to 0.78. In several studies, most of the genetic diversity within a site could be recovered from the nodules of a single plant. When hierarchical analyses were performed on populations within and between sites, the genetic diversity within sites was similar to the genetic diversity between sites. Similarly, the genetic diversity of strain collections originating from multiple hosts and locations was no more diverse than some individual populations and communities. Strain richness and genetic diversity measures were not always correlated for rhizobial populations. Populations with low strain richness were sometimes genetically diverse, and the relationship between the diversity measures varied for different legume species at the same location. We suggest that both strain richness and genetic diversity measures are required to fully describe rhizobial population and community diversity.     

Diversity of rhizobia isolated from an agricultural soil in Argentina based on carbon utilization and effects of herbicides on growth

Seventy-six rhizobial isolates belonging to four different genera were obtained from the root nodules of several legumes (Vicia sativa, Vicia faba, Medicago sativa, Melilotus sp., Glycine max and Lotus corniculatus). The action of five commonly used herbicides [2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate (GF), dicamba, atrazine and metsulfuron-methyl] on the growth of rhizobial strains was assessed. Subsequently, GF and 2,4-D were tested in a minimum broth as C and energy sources for 20 tolerant strains. The ability of these strains to metabolize different carbon sources was studied in order to detect further differences among them. Tolerance of the bacteria to agrochemicals varied; 2,4-D and GF in solid medium inhibited and diminished growth, respectively, in slow-growing rhizobial strains. Among slow-growing strains we detected Bradyrhizobium sp. SJ140 that grew well in broth + GF as the sole C and energy source. No strain was found which could use 2,4-D as sole C source. The 20 strains studied exhibited different patterns of C sources utilization. Cluster analysis revealed three groups, corresponding to four genera of rhizobia: Rhizobium (group I), Sinorhizobium (group II) and Mesorhizobium–Bradyrhizobium (group III). On the basis of the results obtained on responses to herbicides and C sources utilization by the isolates investigated, it was possible to differentiate them at the level of strains. These results evidenced a considerable diversity in rhizobial populations that had not been previously described for Argentinean soils, and suggested a physiological potential to use natural and xenobiotic C sources.     

有机物腐熟剂在水稻田的应用效果试验

进行了添加腐熟剂的早稻秸秆还田腐熟效果试验和对后茬晚稻作物的作用效果试验。结果表明：在早稻秸秆还田的基础上施用广西鸿生源有机物料腐熟剂后,再种植晚稻,能加快早稻秸秆腐熟速度,较未施腐熟剂处理增产315kg/hm^2。     

复合菌剂对玉米秸秆的生物降解作用

为了最大限度地降解农业废弃物玉米秸秆,本研究探讨复合菌剂对玉米秸秆的生物降解作用。采用国家标准中相关测定方法对玉米秸秆中的纤维素和木质素进行测定。结果表明,S-3菌株与白腐真菌复合得到的复合菌剂对玉米秸秆中的纤维素和木质素有很好的降解作用,其最佳降解玉米秸秆的条件为:S-3菌株与白腐菌复合配方为8∶8,料水比为1∶2.5,发酵温度为30℃,发酵时间为17d。在此条件下,秸秆纤维素的降解率为:35.60%,木质素的降解率为:37.41%。