Non-destructive Limits to Seed Growth and Leaf Protease Activities in Nodulating and Non-nodulating Soybean Isolines

Leaf senescence leads to a progressive decline in the photosynthetic competence of the leaf. This paper describes some effects of source:sink imbalance on leaf protein catabolism and senescence in soybean. We manipulated pod growth by restricting 100 or 50 % (PR-100 or PR-50, respectively) of young pods at the R4 stage in plastic drinking straws. This effectively reduces final seed mass without interrupting the vascular connections of pods. Nodulating (NOD+) and non-nodulating (NOD−) isolines of the 'Clay' soybean were grown in drainage lysimeters and three pod-restriction (PR) treatments were compared. Pod restriction decreased seed biomass per plant as a result of lower individual seed mass, which was only partially balanced by the increase in seed number. The nitrogen concentration in seeds remained unchanged in NOD+ plants, while it increased with the degree of sink restriction in seeds of NOD− plants. Leaf soluble protein, CO₂ exchange rate and seed nitrogen content were consistently lower in NOD− plants; the leaf protein level remained stable with time in PR-100 plants, decreased for PR-50 and dropped for controls. Endoprotease (HBase) and carboxypeptidase (CPase) activities were significantly lower in leaves from PR-100 plants, while aminopeptidase activity was enhanced, indicating a de novo synthesis of leaf protein. This is consistent with the reported accumulation of vegetative storage proteins (VSPs) in soybean and other legumes after moderate or severe sink reduction. Thus, small modifications of the source:sink ratio such as those obtained by the non-destructive PR technique have an impact on leaf protein catabolism. Nodulating and non-nodulating soybean isolines showed similar responses to PR in terms of leaf senescence initiation and progression, but the rate of the processes appear to be largely influenced by plant N status.     

栾树对土壤多环芳烃修复机制初探

多环芳烃(PAHs)是一类广泛存在于环境中的有机污染物,由于其致癌性和致突变性而受到广泛关注。采用盆栽实验,研究了栾树在3种污染水平下对土壤中PAHs的去除效果与修复机制。结果表明:在试验浓度范围内(7.35～46.23 mg.kg-1),种植栾树1 a后,PAHs降解率为60.69%～75.14%;比对照(无植物处理)PAHs降解率平均提高了22.96%,且以L2污染水平下降解率最大。栾树能够在一定程度上吸收与累积土壤中PAHs,且累积量与土壤PAHs的添加浓度呈正相关,根部PAHs累积量大于干叶部。修复机制反映出植物-微生物间的交互作用、微生物降解是修复土壤PAHs的主要途径。     

微波辅助提取木棉叶总黄酮研究

[目的]确定从木棉叶中提取总黄酮的优化务件.[方法]通过单因素试验和正交试验对微波辅助提取木棉叶总黄酮的工艺条件进行了探讨,研究了溶剂浓度、料液比、微波功率及微波处理时间对黄酮提取的影响.[结果]木棉叶中总黄酮微波辅助提取的最佳条件为乙醇的体积分数70％,料液比1∶50 g/ml,微波功率为240W,微波处理时间为60s,在此条件下木棉叶中总黄酮含量为6.11％.[结论]微波提取总黄酮的方法简便、高效,可用于木棉叶的质量控制.     

Effects of foliar fertilization on yield,protein, oil and elemental composition of two soybean varieties

Abstract

The effects of foliar fertilization on the yield and seed composition of two soybean (Glycine max L. Merrill) varieties were investigated under mid‐Missouri conditions over a 2‐year period. The foliar fertilizer treatments consisted of (i) 80–8–24–4 (NPKS) kg/ha, (ii) 40–4–12–2 (NPKS) kg/ha, and (in) control (no foliar treatment) with the optimum proportion of N:P:K:S in the solution 10:1:3:0.5 respectively. Nutrient sources were urea, potassium polyphosphate, and potassium sulfate. Water solutions of fertilizers (pH 6.9) containing 0.1% Tween 80 (v/v) were sprayed on the plants using a CO₂ ‐ pressurized back‐pack sprayer. Foliar fertilizer was split between four equal applications during the seed filling period. The variety Mitchell at the higher rate and the variety Williams at the lower fertilizer application rate produced slight, though statistically insignificant, yield increases. At the higher rate of application, the seed protein contents of both varieties increased, while the oil contents decreased. The concentrations of P and K in the seeds were not affected by foliar fertilization, but at the higher rate, there was a small decrease in S content of Williams variety.     

Foliar diagnosis of soybean by dris

Abstract

The Diagnosis and Recommendation Integrated System (DRIS) has proven useful in the interpretation of tissue elemental analyses for many crops, and research was undertaken to apply the same method for foliar diagnosis of soybean (Glycine max [L.] Merr.). Using a data bank in excess of 3500 tissue samples, reference values for evaluating the status of soybean with respect to N, P, K, Ca, Mg, Mn, Fe, Cu, Zn, Mo, B and Al were derived. DRIS diagnoses generally agreed with those obtained by the sufficiency range method. In addition, DRIS assessed the nutrient balance in plant tissue, and identified not only the most‐limiting element, but the order in which other elements would likely become limiting. Further, DRIS was able to diagnose plant nutrient needs earlier in the life of the crop than the sufficiency range method (5 weeks compared to 10 weeks), which would allow remedial steps to be taken earlier. Treatments indicated by DRIS to be needed gave greater yield increases than those indicated by the sufficiency range approach. Geographic differences in DRIS norms were identified, and indicate that regional derivation of diagnostic values may be necessary.     

我国大豆根瘤内生菌资源多样性研究

植物内生菌已成为植物微生态系统中的重要组成部分,根瘤内生菌和根瘤菌普遍共存于特殊的根瘤生 境。比较了根瘤内生菌和根瘤菌与宿主间关系存在的区别,对大豆根瘤内生菌的种类、宿主和适应性、生物固氮、促 进植物生长、增强宿主抗逆、抗病能力以及联合修复环境污染等功能多样性进行论述,指出大豆根瘤内生菌研究的 发展方向,对进一步促进植物生长、发展可持续农业具有重要意义。 ）     

大豆7S球蛋白α'亚基缺失及(a'+a)亚基双缺失品系的回交转育

7S球蛋白α''与α亚基是大豆种子贮藏蛋白的重要组分,是影响大豆营养价值与加工品质的重要因子,同时还是主要的大豆致敏原,降低它们的含量是大豆品质改良育种的最新研究热点之一。以日本育种材料7S球蛋白(α''+α)-亚基双缺失型日B为供体亲本,黑龙江省主栽大豆品种东农47为受体亲本,采用回交转育方法,将α''与(α''+α)-亚基缺失特性导入东农47。结果表明,α''-缺失型(Cc)和(α''+α)-双缺失型(Cd)品系均能正常生长、结实,并能稳定遗传;Cc、Cd产量组分性状的平均值均远高于轮回亲本,蛋白质含量平均值均高于双亲,部分Cd株系籽粒蛋白质总量高达46.7%,脂肪含量平均值介于双亲之间,略高于日B;导入α''-缺失和(α''+α)双缺失性状后,绝大多数氨基酸组分含量和氨基酸总量提高,其中精氨酸和天门冬氨酸平均含量变幅最大。Cd株系籽粒含硫氨基酸含量(蛋氨酸与胱氨酸之和)及氨基酸总量分别比东农47高出0.11和5.56个百分点。说明通过常规育种重组α¢-缺失或(α''+α)-双缺失性状即可提高大豆含硫氨基酸含量,并提高其他氨基酸组分含量及氨基酸总量,在Cc、Cd的BC₂F₃后代群体中有望筛选到α''-缺失或α''与α同时缺失的高产、高含硫氨基酸、优质大豆新品种。     

广金钱草种子质量标准研究

中草药规范化种植的先决条件是具有优质的种子,为了确定广金钱草种子的品质检验方法和质量分级依据,进而为广金钱草种子检验规程和质量标准的制定提供技术支撑,试验对两广地区出产的广金钱草种子的品质指标进行了测定.结果显示,两广地区的广金钱草种子品质指标符合中草药规范化种植的种子要求,其净度可达87.86％以上、千粒重可达1.628～1.918 g、含水量在9.82％以下、发芽势在28.38％～52.73％、发芽率最高可达95.67％、生活力最高可达95.50％;并依据测定数据初步提出了广金钱草种子的质量分级标准,以供生产上参考.     

不同处理方法对栾树种子发芽率的影响

在恒温条件下(24℃),利用不同浓度的赤霉素、硝酸钾、双氧水对经过不同层积天数的栾树种子进行浸种催芽试验.结果表明:以0.3%的硝酸钾溶液浸泡层积了50 d的种子,其发芽率最高,可达到91.0%;其次为900 mg/L的赤霉素溶液浸泡层积时间为50 d的种子,发芽率也达到86%.与对照相比,差异显著.