Inheritance of male fertility restoration of the cytoplasmic-nuclear male-sterile line NJCMS1A of soybean [Glycine max (L) Merr.]

At present, no report on inheritance of male fertility restoration has been released, yet more than 10 cytoplasmic-nuclear male-sterile soybean lines as well as their maintainers and restorers have been developed. Based on our previous work, 25 restorers for the male-sterile line NJCMS1A were identified and the inheritance of male fertility restoration for these restorers was studied. The results showed that F₁s between NJCMS1A and its restorers were completely male-fertile. The numbers of fertile and sterile plants in the F₂ population of Cross I (NJCMS1A × N23601) and Cross II (NJCMS1A × N23683) corresponded to a segregation ratio of 15:1, and the numbers of non-segregation lines, 3:1 segregation lines and 15:1 segregation lines in F_2:3 of the same two crosses fitted a 7:4:4 genotypic segregation ratio. The testcross BC₁F₁s between the F₁s of the above two crosses and NJCMS1A, NJCMS1B showed a 3:1 segregation ratio. Accordingly, it was inferred that two pairs of duplicate dominant genes controlled the male fertility restoration of NJCMS1A in both crosses. Meanwhile, F₂ of other 23 crosses between NJCMS1A and its 23 restorers showed a fertility segregation ratio of 3:1 or 15:1. The F₁s of the five testcrosses between NJCMS1A and the F₁s of five crosses selected from the above 23 crosses showed that fertility segregation was 3:1 in BC₁F₁s between NJCMS1A and F₁s of the crosses of which fertility segregation fitted 15:1 in F₂ population, while fertility segregation in BC₁F₁s was 1:1 for those fertility segregation fitted 3:1 in F₂ population. Allelism tests showed that restore genes of all restorers in the experiment were allelic to two pairs of dominant genes. All results showed that some restorers bore one pair of dominant restore gene and the others bore two pairs of duplicate dominant gene. The mechanism of F₁ male sterility of the cross N8855 × N2899 was discussed.     

大豆细胞质遗传芽黄突变体的发现

本研究新发现一个大豆芽黄突变体NJ89-3。该突变体典型表现为，从第一对真叶开始，新生叶表现明显黄化，但随叶片充分伸展定形，逐渐变为正常绿色。植株最后一张叶片充分伸展定形后，芽黄植株与正常绿色植株并无明显区别。研究表明NJ89-3的芽黄性状由细胞质基因突变引起，属细胞质遗传，建议将此细胞质基因命名为cyt-Yv。     

修剪留茬高度对沟叶结缕草生长的影响

采用称重式蒸渗仪法,在贵州省黔西南地区研究了不同修剪留茬高度对沟叶结缕草的水分利用效率和耗水系数的影响。结果表明:随着修剪留茬高度由3 cm增至不修剪,沟叶结缕草的耗水量由96.33 mm增至386.60 mm,水分利用效率8月份高于7月和9月,以留茬高度6cm的水分利用效率高达0.75 kg·mm^-1·hm^-2。因此对黔西南地区的7、8、9月的沟叶结缕草地区夏剪,留茬高度定在6 cm较为理想,既可以节水又能达到美观效果。     

Soybean Nodule Development and Nitrogenase Activity During the Reproductive Phase: Statistical Modeling Approach

Nitrogenase activity during the reproductive phase of the Hodgson 78 soybean variety was tested in a growth chamber experiment to evaluate its relationships with number, weight and specific nitrogenase activity of the nodules. A multiple regression model is proposed.
The number of nodules did not change, while the total nodule dry weight increased with the increase of the average dry weight.
The regression model adopted showed that the main factors affecting the total nitrogenase activity were the specific activity and the nodule mass, but the former induces the wider variations.
Unlike other crops the counting of the nodules cannot be considered as an indirect predictor for nitrogen fixation.     

黄钩蛱蝶生物学的初步研究

黄钩蛱蝶是药用植物葎草的重要食叶害虫.在南昌一年发生5代为主,部分6代,少数7代,世代重迭,以未交配的成虫过冬.10月初羽化的成虫,当年不再交配和产卵,故越冬成虫即包含了五六七代成虫.受高温干旱的影响,夏季和秋初雌虫的产卵量及卵的孵化率明显低于春季和夏初.因此五六月份为全年发生的为害烈期.     

水分吸收预处理提高菜用大豆种子活力

用40％PEG溶液、饱和湿度空气及多层滤纸控制吸胀预处理,能显著提高菜用大豆(Glycine max L.Merr.)种子的发芽势、发芽率和活力指数,以及抗低温吸胀和浸泡伤害的能力.在PEG溶液和多层滤纸条件下吸胀,明显减缓种子吸胀速率,特别是吸胀初期的速率.而且两者控制吸胀的效果相似.这三种处理显著地减少了种子浸泡液的电导率和紫外吸收物质量以及可溶性糖和氨基酸外渗量.种皮对阻止细胞内含物外渗有重要作用,但PEG等的修复作用主要发生在种皮内活的细胞组织.预处理对膜的修复有良好的效果,可是当种子劣变已伤及修复系统时,这种处理就无效.     

黄淮地区大豆胞囊线虫生理小种的抽样调查与研究

 【目的】探讨黄淮地区大豆胞囊线虫（Heterodera glycines Ichinohe）的种类及其分布。【方法】2001～2003年在黄淮大豆产区依据Riggs的鉴别模式对38个地点大豆胞囊线虫（SCN）生理小种作抽样调查，并结合文献资料，绘制出黄淮地区大豆胞囊线虫生理小种分布图。【结果】大豆胞囊线虫主要分布在山东、河北、北京、山西大部分地区、河南东部与北部、安徽北部；在山西南部及河南西南部地区的抽样调查中未检测到大豆胞囊线虫。其中1号生理小种主要分布在山东济南以南及以东地区，河南北部与河北南部交界地区，河南漯河、周口及安徽阜阳地区。4号生理小种主要分布在河南、山东、安徽交界地区，山西、北京地区，以及山东黄河三角洲地区。2号生理小种主要分布在山东聊城、德州地区，河北石家庄地区，河南焦作、获嘉地区。7号生理小种主要分布在山东半岛和河南开封、滑县、温县等地。5号生理小种在河南和河北有零星分布。另外，在河南商丘地区新发现有9号生理小种。【结论】黄淮地区的优势小种是1号和4号生理小种，抗线虫育种应该以兼抗1号和4号生理小种为主要目标。各生理小种的分布没有明显分界，优势小种分布区域中存在其他生理小种。在过去的10年中，该地区生理小种的组成相对稳定，本研究结果可供大豆抗线虫育种参考。     

Nitrogen accumulation and partitioning in hail‐damaged soybeans 1

Hail damage to an experiment that was being used to investigate nitrogen (N) nutrition of soybeans [Glycine max (L.) Merr.] with ¹⁵N methodology provided a unique opportunity to study the effects of hail damage at the R3 stage of development on N uptake and partitioning through stage R5.8. Field plots were established on a silt loam soil (Typic Hapludol 1). Severely damaged (mean 72% leaf loss) and slightly damaged (mean 26% leaf loss) soybeans were compared for total reduced N and for ¹⁵N concentration in leaflets, petioles, stems, roots, pod walls, and seeds during the 28 days following the hailstrom. The concentration of total N and of ¹⁵N in all organs in both damage treatments declined significantly after the storm, but less in green leaflets (total N), and in green leaflets, green petioles, and pod walls (¹⁵N) of severely than of slightly damaged plants. Measurements on senesced leaflets and petioles showed that the concentration of ¹⁵N also decreased to a greater extent than that of the total N in these organs. This differential loss of ¹⁵N compared with total N suggests that the ¹⁵N was in a form that was less refractory than was the bulk tissue N, and provides evidence of separate mobile pools of N in the plant. Nitrogen budgets were calculated to compare the loss of N and ¹⁵N from abscising leaflets and petioles to the N accumulation of the damaged plants during podfill. These showed that loss from the leaflets and petioles contributed only 7% of the total N accumulated by the plants between R3 and R5.8. This study has exemplified the usefulness of ¹⁵N methodology in investigations of the nutrition and physiology of soybeans suffering leaf damage by hail.     

Seed Treatment with Uniconazole Powder Improves Soybean Seedling Growth under Shading by Corn in Relay Strip Intercropping System

The relay strip intercropping system of wheat-corn-soybean is widely used in southwest China. However, it is hard to obtain a stable production of soybean with this system, since soybean plants grow under shading by corn; the stems are thinner and susceptible to lodging. We examined the effects of seed treatment with uniconazole powder (0, 2, 4 and 8 mg kg-¹ seed) on the growth of soybean seedlings under relay strip intercropping, some morphological characteristics and yield. The seedling height, first internode length, cotyledonary node height and leaf area per plant were decreased, while the stem diameter, root dry weight, shoot dry weight, root volume, leaf greenness and root to shoot dry weight ratio were increased by uniconazole treatment. The root vigor and root active absorption area were also increased significantly by uniconazole treatment. Moreover, 2 and 4 mg kg-¹ uniconazole powder treatment increased shoot dry weight, number of pods per plant, number of seeds per pod and seed yield significantly. Thus, the results suggested that seed treatment with uniconazole powder at a suitable concentration can improve soybean seedling growth, resist the lodging and also increase the seed yield under shading by corn in relay strip intercropping system.     

Comparison of four phosphorus extraction methods on three acid southeastern soils

Abstract

Phosphorus extractants have not been tested extensively in the Southeast. An experiment was carried out to compare four P extractant methods using samples from a field P‐K factorial experiment with soybeans (Glycine max (L.) Merr.) at three locations in Georgia over four years. There were five P rates ranging from none to 80 kg ha^‐1. Soils and plant tissue were sampled at mid‐summer and yields were recorded. The four P extractants compared were Olsen, Mehlich 1, Mehlich 2, and Bray 1. Quadratic regressions for soil P versus plant P and P rates were not significant compared to linear regressions. There were no significant yield responses to P. All extractants except Olsen were similar in their response to added fertilizer P as measured by linear r² values. Olsen P gave lower linear r² values both with P rate and with plant P. Mehlich 1 values were highly correlated with Mehlich 2 (0.94**) and Bray 1 (0.96**). Mehlich 2 and Bray 1 gave nearly the same soil P values with linear regressions of slope of 1.0 and low intercepts. Results from these experiments show that Mehlich 1, Mehlich 2, or Bray 1 could be used successfully on these soils, but that Olsen should be avoided.