吉林省绿豆品种形态性状分析

对吉林省21个绿豆品种的16个形态性状进行了分析,结果表明所有绿豆品种的生长习性、荚色、粒色无多样性,单株产量的多样性指数最高为1.520,荚形的多样性指数最低为0.736。基于形态性状的聚类分析可划分为6大组群。吉林省绿豆品种亲缘关系较近,群体遗传基础狭窄,应拓展亲本来源,改善群体结构。     

Effects of straw mulch on mungbean yield in rice fields with strongly compacted soils

In rice-based lowland areas in the Mekong region, the lack of full irrigation water availability for post-rice legume crops and the poor soil physical and chemical conditions are major constraints for development of sound rice/legume double cropping system. In order to improve legume productivity, use of rice straw mulch and various crop establishment methods were examined in two series of mungbean experiments in Cambodia where soils were coarse and strongly compacted. In one set of experiments conducted at four locations in the first year the effect of straw mulch, planting method (manual vs seed drill) and tillage method (conventional vs no-till) was examined. Another set of experiments were conducted in the second year at three locations with four levels of mulch under two planting densities. On average in year 1, mulching of rice straw at 1.5 t/ha increased mungbean crop establishment from 72 to 83%, reduced weed biomass from 164 to 123 kg/ha and increased yield from 228 to 332 kg/ha. Mulch was effective in conserving soil moisture, and even at maturity the mulched area had on average 1% higher soil moisture content. The amount of mulch between 1 and 2 t/ha did not show consistent effects in year 2, partly because some mulch treatments resulted in excessive soil moisture content and were not effective. Rice straw mulch had a significant effect on mungbean yield in 6 out of the 7 experiments conducted in two years, and mean yield increase was 35%. This yield advantage was attributed to better crop establishment, improved growth and reduced weed pressure, but in some cases only one or two of these factors were effective. On the other hand, planting method, tillage method and planting density had only small effects on mungbean yield in most experiments. Only in one location out of four tested, the no-till treatment produced significantly higher yield than the conventional method. Seed drill produced similar mungbean establishment and grain yield to the manual planting suggesting that the planter can be used to save the labour cost which is increasing rapidly in the Mekong region. Maximum root depth varied little with mulch or planting density, and was shallow (<20 cm) in all three locations where this character was determined. It is concluded that while rice straw mulch increased yield of mungbean following rice, the inability of mungbean roots to penetrate the hard pan is a major constraint for development of a sound rice/mungbean cropping system in the lowlands with compacted soils.     

Inheritance of seed resistance to bruchids in cultivated mungbean (Vigna radiata, L. Wilczek)

Bruchid beetles or seed weevils are the most devastating stored pests of grain legumes causing considerable loss to mungbean (Vigna radiata (L.) Wilczek). Breeding for bruchid resistance is a major goal in mungbean improvement. Few sources of resistance in cultivated genepool were identified and characterized, however, there has been no study on the genetic control of the resistance. In this study, we investigated the inheritance of seed resistance to Callosobruchus chinensis (L.) and C. maculatus (F.) in two landrace mungbean accessions, V2709BG and V2802BG. The F₁, F₂ and BC generations were developed from crosses between the resistant and susceptible accessions and evaluated for resistance to the insects. It was found that resistance to bruchids in seeds is controlled by maternal plant genotype. All F₁ plants derived from both direct and reciprocal crosses exhibited resistance to the bruchids. Segregation pattern of reaction to the beetles in the F₂ and backcross populations showed that the resistance is controlled by a major gene, with resistance is dominant at varying degrees of expressivity. Although the presence of modifiers was also observed. The gene is likely the same locus in both V2709BG and V2802BG. The resistant gene is considered very useful in breeding for seed resistance to bruchids in mungbean.     

Attributes affecting residual benefits of N<Subscript>2</Subscript>-fixing mungbean and groundnut cultivars

Legumes grown for grain may or may not contribute net N benefits to soil and succeeding crops. An experiment was conducted to assess N₂ fixation attributes of six mungbean cultivars and two groundnut cultivars (Tainan 9 and Non-nod), which determine their residual benefit to the subsequent maize. Nodule number and dry weight of mungbeans peaked early (at 45 days) and declined thereafter strongly. In groundnut nodulation peaked later and declined only by 50% towards the final harvest. The N₂-fixing groundnut produced higher total dry matter yield than mungbeans; however, mungbeans produced higher seed yields. Dry matter harvest index and nitrogen harvest index (NHI) were higher in mungbeans (average 0.44 and 0.69) than groundnut (0.23 and 0.47, respectively, in Tainan 9). The percentage of nitrogen derived from air (%Ndfa, ¹⁵N isotope dilution) ranged from 54% to 62% in mungbeans, similar to that of groundnut (64%). However, Tainan 9 fixed more N₂ (82 kg N ha^–1) than mungbeans (35–50 kg N ha^–1) and resulted in a positive soil net N balance (+22 kg N ha^–1) while negative values were found for Non-nod groundnut and mungbeans (–3 to –12 kg N ha^–1). Maize grown after groundnut Tainan 9 had the highest total dry weight and total N uptake. This was equivalent to maize grown in fallow plots, which received 60–90 kg N ha^–1, while the respective benefits after mungbeans were 30–60 kg N ha^–1. Maize yield was directly related to the amount of residue N returned. Thus, the combination of high N yield, residue quality, %Ndfa and low NHI proved most beneficial to soil fertility and the succeeding crop.     

Development of a molecular marker for a bruchid (Callosobruchus chinensis L.) resistance gene in mungbean

Bruchid, Callosobruchus spp. (Coleoptera: Bruchidae), is a serious pest during storage of seeds of mungbean (Vigna radiata (L.) Wilczek) and other Vigna species. A source of resistance to this pest has been identified in Vigna sublobata (Roxb.) Bairig. accession TC1966. Two hundred recombinant inbred lines at the F₁₂ generation have been developed for molecular mapping of bruchid resistance (Br) gene in TC1966. Through bulked segregant analysis (BSA), ten randomly amplified polymorphic DNA (RAPD) markers associated with the bruchid resistance gene were successfully identified. A total of four closely linked RAPDs were cloned and transformed into sequence characterized amplified region (SCAR) and cleaved amplified polymorphism (CAP) markers. Seven CAPs developed from the identified RAPD markers showed tighter linkage with the Br gene than the original RAPD. Through transformation of RAPDs into CAPs, codominant markers for bruchid resistance were successfully obtained. Homozygous genotypes of these PCR-based markers were estimated to contribute 85% of the variance for seed damage when the insect assay was performed under favorable growth conditions for bruchid.     

Comparison of symbiotic effectiveness of Rhizobium sp. with positive hydrogen-uptake activity compared with negative mutants in relation to nitrogen fixation in mungbean (Vigna radiata L.)

H₂ uptake activity was well distributed in Rhizobium sp. strains isolated from nodules of mung-bean (Vigna radiata L.). Two effective strains, RMP1 und RMP2, exhibiting significantly higher H₂ uptake activity were subjected to mutagenesis with nitrosoguanidine. The respective mutation frequencies were 0.18 and 0.19%. Three Hup^- mutants each of RMP1 und RMP2 were compared with the wild-type parent strains under pot culture experiments to evaluate the significance of the H₂ uptake system in biological N₂ fixation. Nodulation capabilities, plant growth characteristics, and the chlorophyll content of the leaves were significantly reduced in the plants treated with Hup^- mutants. Nitrogenase activity in Hup^- nodules was reduced by 8–41%. Similarly, N accumulation was also reduced singificantly.     

Impact of Different Weed Types on Growth and Yield of Mungbean (Vigna radiata L. Wilczek)

The influence of different weed types (grass, broadleaved and sedge species) on growth and yield parameters of mungbean ( Vigna radiata L. Wilczek) was evaluated under field conditions. The presence of all types of weeks had the most significant effect on growth and yields of mungbean. Broadleaved species alone had a greater adverse effect than grasses, and the influence of sedges was the lowest. The adverse effect of weeds was most prominent on vegetative growth. The influence on yield components reduced with time. However, the adverse impact of weeds on yields was similar to that on vegetative growth. A significant correlation between weed biomass and yield loss was observed. The study indicated the critical competitive period to be in the vegetative phase. Some possible implications for selective weeding are presented.     

5种常用除草剂对绿豆杂草的田间防除效果

为了筛选适宜绿豆田杂草防除的除草剂,以市场销售量大、易购买为前提,选择5种常用除草剂,采用大区对比试验设计,以人工锄草和不锄草处理为对照,设75%噻吩磺隆90 g/hm2+960 g/L精异丙甲草胺1 872 m L/hm2、乙草胺2 250 m L/hm2播后苗前土表喷施处理,15%乙羧氟草醚乳油900 m L/hm2、15%乙羧氟草醚乳油900 m L/hm2+15%精稳杀得乳油1 050 m L/hm2、15%精稳杀得乳油1 050 m L/hm2苗后茎叶喷施处理,进行了不同除草剂及配比对绿豆(冀绿10号)田杂草防除效果的研究。结果表明:参试除草剂均对绿豆安全,其中,75%噻吩磺隆90 g/hm2与960 g/L精异丙甲草胺1 872 m L/hm2复配在绿豆播后苗前进行土表喷施对杂草防效显著;15%乙羧氟草醚乳油与15%精稳杀得乳油复配在绿豆出苗后定向喷施对绿豆田杂草防除效果最好,施药后30 d对绿豆田主要阔叶草杂草马齿苋、反枝苋及禾本科杂草牛筋草的鲜重防效分别为100%、100%和95.62%,绿豆产量为2 799.14 kg/hm2,较人工锄草处理增产2.57%。在绿豆播后苗前用75%噻吩磺隆90 g/hm2与960 g/L精异丙甲草胺1 872 m L/hm2复配剂进行土表喷施、绿豆出苗后用15%乙羧氟草醚乳油与15%精稳杀得乳油复配剂进行茎叶喷施对绿豆田杂草防除效果较好,可以用于绿豆田间杂草防除。     

绿豆新品种冀绿9239的选育

冀绿9239新品种以冀引3号为母本、Vc2802A为父本杂交选育而成,具有高产、早熟、抗病毒病、抗逆性强和适应性广等特点,适宜在春播区的黑龙江、辽宁、山西、新疆、宁夏以及夏播区的河北、河南、江苏、四川、北京、山东等地种植。     

国家食用豆产业技术体系绿豆新品种（系）联合鉴定

分析了国家食用豆产业技术体系2016-2017年24个绿豆新品种（系）在20个试验点的鉴定结果,以期为新品种（系）的进一步示范推广提供参考。结果显示,不同生态区绿豆表型差异明显,以株高、主茎分枝数、单株荚数和单株产量的变异最明显（平均变异系数均介于20%~40%）,单荚粒数、百粒重、生育期变异不明显（平均变异系数均介于10%~20%）。综合分析发现,冀绿0816、JLPX02、品绿2011-06的生态适应性最广,在20个参试点均适宜种植,适应性最差的为苏绿16-10,仅在江苏南京能够正常生长成熟。根据表型及产量表现,分别筛选出适宜不同生态区种植的绿豆新品种（系）,为这些品种（系）的进一步示范推广奠定基础。