玉米苗期抗旱促生微生物拌种剂应用效果初报

采用微生物拌种剂进行拌种处理和田间小区对比试验,研究微生物拌种剂在田间的应用效果。结果表明,使用微生物拌种剂可促进玉米根系发育,增加玉米株高、植株干物质积累和百粒重,出苗率提高4.6%,增产4.2%。试验结果为微生物拌种剂的推广应用提供了科学依据。     

生物肥在不同作物上的应用效果

通过田间小区试验和大区示范,对生物肥在大豆、水稻上的应用效果进行了探讨。小区试验结果表明,生物肥与化肥配合施用对作物生长发育产生了显著的影响。与单施氮、磷、钾化肥相比,显著提高了作物的株高、荚(穗)数、粒数、粒重,与单施化肥和不施肥对照比较,大豆分别增产6.9~7.9%和8.8~10.7%%;水稻分别增产7.1~8.7%和6.2~8.0%。大区示范结果也表明,化肥配合生物肥能够促早熟,明显增加株荚数、株粒数和百粒重而获增产,增产率为10.13%。     

一次基施水稻控释肥技术的养分利用率及增产效果

通过盆栽试验、田间小区试验和生产大面积应用示范研究了一次基施水稻控释肥的养分利用率及其增产效果.结果表明,一次基施水稻控释肥技术与等养分量的专用肥处理比较,盆栽试验相对提高氮素利用率12.2%～22.7%,磷素利用率7.0%～35.0%;小区试验相对提高氮素利用率17.1%.综合广东不同水稻生态类型稻作区连续3年共167点(次)应用示范结果,表明一次基施水稻控释肥技术较常规分次施肥平均减少氮和磷养分用量分别为22.11%和21.81%,降低了施肥成本,获得8.2%的增产效果.     

植物根际促生菌作用机制研究进展

植物在生长过程中可能会遭受许多生物和非生物因素胁迫,从而降低生物产量. 人们已知一些植物在不同因素的刺激诱导下,能系统化建立抵抗或忍受不利因素的机制,植物根际促生菌（PGPR）就是其中一类能定殖于根系并促进植物生长的细菌.本文对PGPR促生机制进行归纳和总结,系统阐述了诱导体系抗性和诱导体系产生忍耐力两大促生机制.PGPR的作用机制的多样性暗示着其可能在更多的农业生态系统中得到应用.     

根际促生菌提高植物抗盐碱性的研究进展

土壤盐碱化已成为限制作物生长及产量的主要因素之一,严重制约农业的发展。提高作物的抗盐碱性,为提高我国农业持续高效发展奠定基础。从根际促生菌研究现状入手,介绍耐盐碱根际促生菌(Plant growth-promoting rhizobacteria,PGPR)的多样性。综述根际促生菌诱导植物建立抵抗或忍耐盐碱胁迫的机制,主要是通过产生植物激素、1-氨基-环丙烷-1-羧酸(ACC)脱氨酶、抗氧化防御物质、渗透调节物质、胞外多糖及挥发性化合物等生理活性物质,改变植物生理及物质代谢水平;另外,一些PGPR通过调节植物盐碱抗性相关基因及蛋白的表达,增强植物抗盐碱能力。通过对耐盐碱根际促生菌及其与植物互作进行展望,为大规模利用根际促生菌缓解盐碱土壤中植物的盐胁迫损伤、增加产量提供重要参考。     

植物根际促生菌的筛选及其对玉米的促生效应

[目的]以不同植物根及根际土壤为研究材料,进行植物根际促生菌(PGPR)的筛选,并探索其植物促生作用机制.[方法]以解磷、固氮、产氨、产IAA和拮抗3种常见病原真菌为筛选标准,测定了初筛菌株的多项促生能力,并通过对这些菌分别单独回接和多菌混接的玉米盆栽试验,测定了其对玉米的促生效应.[结果]从渭南、成阳、安康、商洛和榆林5地分离得到的158株菌中有17株茵具有上述多种植物促生作用的菌株.盆栽试验的测定结果表明:单独接种和多菌混合接种在玉米株高、根长、茎长、茎平均直径和干重方面与对照组相比较都有所增加,尤其是在多个指标上,多菌混合接种所显示出的促生效应均明显优于单菌接种.[结论]所筛选到的具有多种促生能力的菌株,可以为进一步构建植物根际促生菌(PGPR)菌群提供良好的种质资源.     

大豆连作障碍研究Ⅲ.海洋放线菌MB-97促进连作大豆增产机理

海洋放线菌MB-97能在重荐大豆根际成功定殖,对克服重荐大豆连作障碍具有显著作用,抑制大豆根际致害微生物（DRMO）紫青霉菌的生长繁殖达80%,减轻了土壤毒素的危害;防治因大豆连作而加重的土传真菌性病害如镰刀菌等引起的根腐病达50%以上,调节优化大豆根际土壤微生物区系。B/F值显著上升,使土壤由低肥力的“真菌型”向高肥力的“细菌型”转化;MB-97对大豆有生长刺激作用,田间试验结果平均增产大豆15.2%,表明海洋放线菌MB-97是一株优良的植物根际促生菌（PGPR）。     

植物根际促生菌的筛选及鉴定

【目的】植物根际促生菌(PGPR)和植物的互作关系往往不稳定,PGPR菌群有可能提高菌株对野外环境的适应性。为此,本文根据PGPR促生机制的多样性,从不同植物根际土壤进行了PGPR的筛选及鉴定。【方法】首先,按照固氮、解磷、解钾、拮抗6种常见病原真菌,同时能在植物根际定殖为基本初筛标准,然后在实验室条件下测定初筛菌株的多项促生能力(PGP),最后通过生理生化试验和16SrRNA基因序列分析对所筛菌株进行鉴定。【结果】从江苏扬州、盐城等地土壤样品筛选出14株PGPR,具有体外抑菌、产NH3、产IAA、产HCN、产嗜铁素、解磷、溶钾、固氮以及产抗生素等促生能力。分类鉴定结果显示:7株属于假单胞菌属(Pseudomonas)、3株属于类芽孢杆菌属(Paenibacillus)、2株为芽孢杆菌属(Bacillus)、1株为布克霍尔德氏菌属(Burkholderia)、1株为欧文氏菌属(Erwinia)。【结论】所筛细菌具有多种促生能力,且能在根际定殖,为进一步构建多功能PGPR广适菌群提供菌株资源。     

植物根际促生菌（PGPR）的研究与应用前景

植物土传病害难以防治,植物根际促生菌(plant growth—promoting rhizobacteria,PGPR)的深入研究和发展为解决这一难题展现了诱人的前景．PGPR能够高密度地在植物根际定殖,兼有抑制植物病原菌、根际有害微生物,以及促进植物生长并增加作物产量的作用,更重要的是有些PGPR能够诱导植物产生系统抗性(induced systemic resistance,ISR),从而提高植物整体的抗病能力．近20年来,国外这一领域的研究十分活跃,已有很多成功应用的PGPR产品,国内应大力加强基础与应用的研究,并推进其产业化的发展．     

干旱下接种根际促生细菌对苹果实生苗光合和生理生态特性的影响

本试验研究了接种根际促生细菌(PGPR)对干旱条件下植物光合和生理生态特性的影响,以期为PGPR在植物抗旱中的应用提供理论依据.采用盆栽试验,以苹果实生幼苗为供试植物,以经过筛选得到的既具有1-氨基环丙烷-1-羧酸(ACC)脱氨酶活性又具有较强溶磷能力的根际促生菌YX₂为供试菌株,设置正常水分(CK)、轻度干旱(LD)、中度干旱(MD)和重度干旱(SD),其相应含水量分别为田间持水量的70%～80%、55%～65%、40%～50%、25%～35%,研究不同程度干旱胁迫条件下接种YX₂对苹果实生幼苗光合和生理生态特性的影响.结果表明: 与未接种处理相比,干旱环境下接种YX₂提高了苹果幼苗叶片的相对含水量、叶绿素含量、抗氧化酶活性、叶绿素荧光值、气孔导度和光合性能,降低了相对电导率、渗透调节物质和丙二醛的积累,缓解了干旱胁迫对净光合速率的抑制,增强了抗氧化系统的防御能力,减少了细胞膜过氧化伤害,提高了植株抗旱性能.     

Tolerance of Soybean to Heterodera glycines

Seven soybeans were selected from 200 entries evaluated for tolerance to soybean cyst nematode (SCN), Heterodera glycines. Tolerance to SCN was measured by comparing the seed yield from aldicarb-treated vs. nontreated plots. A yield response index (YRI) was calculated for each entry: YRI = (seed yield from nontreated plot/seed yield from treated plot) × 100. The soybean entries Coker 156, PI 97100, and S79-8059 exhibited high tolerance (YRI) to SCN when compared to Essex even though they became heavily infected with SCN. Tolerance in soybeans to SCN may be useful in pest management programs designed to stabilize soybean yield.     

A possible role of allantion and the influence of nodulation on its production in soybean plants

Summary To examine the influence of nodulation on the production of nitrogenous compounds, soybean plants (Glycine max var. Tamanishiki) were grown with or without N-fertilizer in the field, and the changes in amino-N and allantoin-N content in the different organs were determined throughout the growth period. In the stem allantoin-N markedly increased after the flowering period and then decreased during seed formation. Allantoin accumulated in the pod (up to 70 per cent of total alcohol soluble-N) during pod formation, while in the seed the main N-compounds were amino acids, the allantoin concentration being very low. In well-nodulated soybeans grown without N-fertilizer, allantoin content in every plant organ was always high compared to beans grown with N-fertilizer, but amino-N content was comparatively low.Another experiment, in which soybean plants were allowed to form nodules by growing on a N-free medium, and in which a fixed-N supply was then controlled by the addition of various levels of ammonium, was made in a greenhouse. When nodules were formed, the subsequent addition of high concentrations of ammonium caused the accumulation of allantoin as well as the accumulation of amides and arginine. A possible role for allantoin and some aspects of its production in soybeans are discussed. re]19760421     

Study on the Superoxide Dismutase of Soybean Seeds from Different Species in Subgenus

The SOD isoenzymes of different soybeans were studied in this experiment and the results showed that: 1. there were 7 SOD isoenzyme bands in all soybean genotypes used in this experiment, 2. the SOD activity (unit/g fr. wt.) in different soybean seeds decreased as the evolutionary process advanced, 3 the SOD activity decreased as the wt./100 seeds increased, and the color of seed coat changed from black to yellow. The relationship between SOD activity and the evolutionary process was discussed.     

Population genetic structure of Japanese wild soybean (Glycine soja) based on microsatellite variation

The research objectives were to determine aspects of the population dynamics relevant to effective monitoring of gene flow in the soybean crop complex in Japan. Using 20 microsatellite primers, 616 individuals from 77 wild soybean (Glycine soja) populations were analysed. All samples were of small seed size (< 0.03 g), were directly collected in the field and came from all parts of Japan where wild soybeans grow, except Hokkaido. Japanese wild soybean showed significant reduction in observed heterozygosity, low outcrossing rate (mean 3.4%) and strong genetic differentiation among populations. However, the individual assignment test revealed evidence of rare long-distance seed dispersal (> 10 km) events among populations, and spatial autocorrelation analysis revealed that populations within a radius of 100 km showed a close genetic relationship to one another. When analysis of graphical ordination was applied to compare the microsatellite variation of wild soybean with that of 53 widely grown Japanese varieties of cultivated soybean (Glycine max), the primary factor of genetic differentiation was based on differences between wild and cultivated soybeans and the secondary factor was geographical differentiation of wild soybean populations. Admixture analysis revealed that 6.8% of individuals appear to show introgression from cultivated soybeans. These results indicated that population genetic structure of Japanese wild soybean is (i) strongly affected by the founder effect due to seed dispersal and inbreeding strategy, (ii) generally well differentiated from cultivated soybean, but (iii) introgression from cultivated soybean occurs. The implications of the results for the release of transgenic soybeans where wild soybeans grow are discussed.     

不同结荚习性夏大豆种质的农艺表现及其与产量的相关分析

以533份不同结荚习性大豆种质为试验材料,研究了不同结荚习性大豆种质在黄淮夏播生态区的农艺性状表现,并对主要农艺性状和产量的相关性进行了分析。结果表明:大豆种质的营养期、株高、有效分枝、单株荚数、倒伏性、株型等性状的平均值随无限-亚有限-有限结荚习性递减,生殖期、单株粒重、百粒重、小区产量等性状平均值的变化趋势则相反。相关分析表明,无限结荚习性种质的产量与株高、单株粒重呈极显著正相关,偏相关系数分别为0.602**、0.566**,与有效分枝、倒伏性呈显著负相关,偏相关系数分别为-0.384*、-0.451*。亚有限结荚习性种质的产量与生殖期、单株粒重呈显著、极显著正相关,偏相关系数分别为0.156*、0.536*,与有效分枝呈极显著负相关,偏相关系数为-0.323**。有限结荚习性种质的产量与单株粒重、株高呈极显著正相关,偏相关系数分别为0.433**、0.262**,与株型、单株荚数呈显著、极显著负相关,偏相关系数分别为-0.149*、-0.198**。结合不同结荚习性品种的生长特点,本研究认为,无限结荚习性品种株高较高且株高与产量呈极显著正相关,适合干旱地区种植;亚有限结荚习性品种生殖期与产量呈正相关,生殖期内生长旺盛需要较多的养分供应;有限结荚习性品种的营养生长持续时间短,株高较矮,吸收光能有限,实现高产主要依赖各性状器官间的平衡。生产中,有限结荚习性品种的营养生长期间既需要充足的肥水促其生长,又要防止旺长。     

不同进化类型大豆种子超氧物歧化酶的比较

本文对不同进化类型大豆种子超氧物歧化酶(SOD)进行了比较分析。结果表明:(1)供试三种进化类型大豆种子的 SOD 同工酶酶谱一致,均为7条,其中一条为 Ma-SOD,其余6条为 Cu-Zn-SOD。(2)SOD 活性表现为:野生类型明显高于中间类型,中间类型明显高于栽培类型。(3)随着大豆籽粒百粒重的增大,种胚的 SOD 活性降低。(4)种皮颜色由黑到黄,种皮的 SOD 活性降低。讨论了大豆种子 SOD 活性与 Sofa 亚属内大豆进化的关系。     

Genotypic differences in cadmium uptake and distribution in soybeans

In order to investigate the genetic differences in uptake and distribution of cadmium in soybeans, 17 varieties of soybean were grown first in soil and then four or five varieties of soybean were grown in nutrient solution with different levels of cadmium.Significant genotypic differences in seed cadmium levels were found. The seed cadmium concentration was lowest for the En-b0-1-2 soybean variety, and highest for Harosoy, in both field and pot experiments. The seed cadmium levels of Tohoku 128, a cross between Enrei and Suzuyutaka, were intermediate between those of the parents. For four soil types, containing from 0.2 to 6.5 mg kg^–1 extractable cadmium, the ranking of soybean genotypes based on seed cadmium level was similar, indicating that there is a genetic factor involved in the varietal differences in cadmium concentration. Among the four soybean varieties tested in one experiment in the present study, the cadmium concentrations in leaves, stems and pods as well as the total cadmium uptake were lowest for En-b0-1-2. These results suggest that cadmium uptake and/or translocation from root to shoot are low in En-b0-1-2. In solution culture containing 100 g L^–1 cadmium, the cadmium concentrations in seeds, stems and pods at the seed maturation stage were also the lowest for En-b0-1-2. In a second experiment, the cadmium concentrations in the leaves, stem and petiole were lower at both 7 and 15 days after the addition of cadmium to the nutrient solution for En-b0-1-2 and Enrei than for Tohoku 128, Suzuyutaka and Harosoy; however, the cadmium concentrations of roots for En-b0-1-2 and Enrei were higher than for the other varieties. We propose that the lower levels of cadmium found in the seeds of certain varieties of soybean result from the combination of lower initial uptake and retention of higher levels of cadmium in the roots, thus limiting its translocation to the shoot.     

中国野生大豆(Glycine soja)遗传资源主要形态、遗传变异和结构

介绍了我国野生大豆遗传资源主要的形态类型、物种内遗传关系和遗传结构。进化的瓶颈不仅发生在由野生大豆到栽培大豆,也以另一种方式"分化瓶颈"出现于同性状的不同表型类型之间。野生大豆种内种子大小类型是否存在遗传分化?野生和半野生大豆的边界在哪?半野生大豆如何产生的?半野生大豆遗传上密切于栽培种还是野生种?百粒重3～4g的小粒半野生大豆与百粒重8.5g以上的特大粒半野生大豆是否有遗传差异?百粒重8.5g以上的特大粒半野生大豆是否属于栽培大豆?野生大豆的种皮色和种子大小哪个更能反映进化程度?栽培大豆基因是否已经渗入到野生大豆?对这些在学术界常年存在的疑问本文介绍了我们的研究答案。我们认为"真"半野生大豆不存在于现在中国半野生资源收集品中;一些野生大豆中的白花、灰毛、无泥膜性状来源于栽培大豆的基因渗透。     

Fitness Components and Selection of Biotypes of Heterodera glycines

Survival of biotypes of Heterodera glycines was studied in microplots and in the field. The field population was subjected to various cropping sequences. Viability of eggs overwintered in microplots was determined each spring by percentage hatch, percentage of hatched eggs penetrating roots, and numbers of females developing on Peking and PI 88788 soybeans. Eggs from the field were collected in the spring and fall and assayed for ability to develop on Peking and PI 88788. Hatch of isolates overwintered in the microplots averaged 13% in May 1989 and 19% in 1990. No differences in hatch were detected among the isolates in 1989. Numbers of juveniles penetrating susceptible roots averaged less than 20% of the hatched eggs each year. An isolate of a biotype parasitic on susceptible soybeans and the resistant soybean PI 88788 penetrated roots more successfully than other biotypes. A second isolate from North Carolina, parasitic on susceptible soybeans, PI 88788, and the resistant soybean Peking experienced selection against development on Peking during two winters. Only 17 % of the expected numbers of females developed on Peking from this isolate. In the microplot experiment, parasitism of PI 88788 and Peking had a selective disadvantage (selection coefficient) of s = 0.29 and 0.62 over all isolates, respectively. In the field experiment, the relative numbers of cysts on Peking and PI 88788 increased between the spring and fall on soybean, then decreased over the winter and under corn. Selection coefficients against parasitism of PI 88788 and Peking averaged 0,19 and 0.3 in the field population. In neither experiment did juveniles lose their ability to parasitize susceptible soybeans.     

Cytokinin Regulation of Flower and Pod Set in Soybeans (Glycine max(L.) Merr.)

Exogenous application of cytokinin to raceme tissues of soybean(Glycine max(L.) Merr.) has been shown to stimulate flower productionand to prevent flower abortion. The effects of these hormoneapplications have been ascertained for treated tissues, butthe effects of cytokinins on total seed yields in treated plantshave not been evaluated. Our objectives were to examine theeffects of systemic cytokinin applications on soybean yieldsusing an experimental line of soybeans, SD-87001, that has beenshown to be highly sensitive to exogenous cytokinin application.Soybeans were grown hydroponically or in pots in the greenhouse,and 6-benzylaminopurine (BA) was introduced into the xylem streamthrough a cotton wick for 2 weeks during anthesis. After theplants had matured, the number of pods, seeds per pod, and thetotal seed weight per plant were measured. In the greenhouse,application of 3.4 x 10^-7 moles of BA resulted in a 79% increasein seed yield compared with controls. Results of field trialsshowed much greater variability within treatments, with consistent,but non-significant increases in seed number and total yieldsof about 3%. Data suggest that cytokinin levels play a significantrole in determining total yield in soybeans, and that increasingcytokinin concentrations in certain environments may resultin increased total seed production. Copyright 2001 Annals ofBotany Company Glycine max, soybean, flower abortion, cytokinin, 6-benzylaminopurine, hydroponic, seed yield, wicking