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61.
铬胁迫对黄豆生理特性的FTIR研究和铬积累特征   总被引:1,自引:0,他引:1  
为了对Cr6+污染土壤修复提供参考依据。通过水培,研究了不同Cr6+水平对黄豆幼苗根、茎、叶的傅立叶红外光谱(FTIR)图谱变化,同时测定Cr6+的亚细胞分布和Cr6+富集的影响。结果表明:幼苗对Cr6+的积累能力与处理浓度呈正比。其叶片富集的Cr6+在细胞壁分布最多(37.14%~63.52%),线粒体和叶绿体最少(<12%)。根组织在1064、1404、1635、2924、3417 cm-1等处峰高呈先升后降的变化趋势,可能是在低Cr6+浓度,通过增加糖类和氨基酸等有机物含量来响应Cr6+胁迫;茎组织在1072、1427、1643、2924、3387 cm-1等处峰高呈现不显著变化趋势;叶组织在1110、1396、1651、2924、3433 cm-1等处峰高先降后升,表明叶中一些富含O-H小分子有机物质(碳水化合物)被运输到根部螯合Cr6+来响应低Cr6+胁迫。研究结果表明,黄豆幼苗能有效地吸收土壤中的Cr6+,在Cr6+污染土壤植物修复技术领域,拥有潜在的利用价值。  相似文献   
62.
Salt-affected soils are generally classified into two main categories: saline and sodic (alkaline). Developing and using soybean (Glycine max (L.) Merr) cultivars with high salt tolerance is an effective way of maintaining sustainable production in areas where soybean growth is threatened by salt stress. Early classical genetics studies revealed that saline tolerance was conditioned by a single dominant gene. Recently, a series of studies consistently revealed a major quantitative trait locus (QTL) for saline tolerance located on linkage group N (chromosome 3) around the SSR markers Satt255 and Sat_091; other minor QTLs were also reported. In the case of sodic tolerance, most studies focused on iron deficiency caused by a high soil pH, and several QTLs associated with iron deficiency were identified. A wild soybean (Glycine soja Sieb. & Zucc.) accession with high sodic tolerance was recently identified, and a significant QTL for sodic tolerance was detected on linkage group D2 (chromosome 17). These studies demonstrated that saline and sodic tolerances were controlled by different genes in soybean. DNA markers closely associated with these QTLs can be used for marker-assisted selection to pyramid tolerance genes in soybean for both saline and sodic stresses.  相似文献   
63.
New aspects of soybean somatic embryogenesis   总被引:4,自引:0,他引:4  
Somatic embryo formation from immature cotyledons was improved in the following ways: by cutting into sections, supplementing culture media with spermine and using solid/liquid/solid type of culture. Cut cotyledons of the eight genotypes examined expressed a higher ability for somatic embryogenesis than whole cotyledons. Of the three polyamines tested, spermine considerably stimulated and putrescine slightly inhibited induction of somatic embryos. The ability of embryoid formation on medium with spermidine depended on the genotype. The solid/liquid/solid type of culture was better than the continuous solid culture. The best nitrogen ion content for the subculture of somatic embryos was 10 mM NH4NO3 and 30 mM KNO3. The possibility of using these modifications in Agrobacterium transformation is discussed.  相似文献   
64.
Summary Soybean DNA fingerprints were analyzed by digoxigenin-labeled oligonucleotide probes complementary to simple repetitive sequences. The clearest and most polymorphic patterns were obtained with (AAT)6 as a probe, with which all 47 soybean cultivars tested could be distinguished. However, DNA fingerprints of individuals within cultivars showed the same pattern. Using (CT)8, (GAA)5 or (AAGG)4 as probes, clear polymorphic patterns among cultivars and accessions in the subgenus Soja (Glycine max and Glycine soja) were not observed, while quite different patterns were found in accessions in the subgenus Glycine. The results suggest that G. max and G. soja are closer in their genome structure. DNA fingerprints of reciprocal crosses between cultivars and accessions in the subgenus Soja were similar, and contained bands of both parents. In an F2 population from these crosses, such bands segregated in a Mendelian fashion.  相似文献   
65.
南方菜用大豆种子越夏贮藏的研究   总被引:2,自引:0,他引:2  
孟祥栋  李曙轩 《种子》1991,(3):16-18
前言菜用大豆(Glycine max L.)俗称毛豆,我国南方普遍栽培。早熟品种如“四月拔”、“五月拔”一般在2月下旬至3月上旬播种,6月上旬开始收获。其种子在采收后要经过高温、多雨的夏季而使生活力下降。而且翌年早春播种,由于气温低和土壤湿度大,常常发生出苗慢、出苗率低,甚至烂种的现象,影响全苗和壮苗,是生产上存在的重要问题。本研究的目的,即是通过采用几种不同的简易贮藏方法比较,来寻找有效地防止菜用大豆种子越夏贮藏过程中活力下降的措施。  相似文献   
66.
Summary Interspecific hybrids have been obtained in an incompatible cross between Glycine max and G. tomentella through the in vitro culture of hybrid embryos. The percentage of successful pod setting in the crosses averaged 12.8% but there were marked differences depending on the soybean cultivar used as the female parent. Hybrid embryos at globular to heart stages were extracted from the embryo sac 15–25 days after pollination and cultured in vitro. Hybrid plants were successfully obtained by culturing the embryos on B5 medium supplemented with 0.1 mg/l IBA followed by culture on B5 medium supplemented with 0.1 mg/l TBA plus 0.25 mg/l 2-iP. The F1 plants resembled the wild male parent in growth form, but had an intermediate leaf shape between that of the parents.  相似文献   
67.
Three soybean ( Glycine max L.) culivars, Lee-74, Wright , and Ra 401 , were subjected to 100 % (control), 75 %, and 50 % of field capacity during vegetative (VI), flowering (R2), and pod-filling (R4) stages in greenhouse and field studies. Stress applied at R2 significantly reduced the yield in the greenhouse, while in the field, the maximum reduction was observed when the plants were subjected to stress at R4. Stress during VI reduced the yield components less than stress applied during R2 or R4 stages in both studies. The pod number and seed weight were the yield components most affected by drought stress, and the number of seeds per pod the least affected. Yield stress index was significantly correlated with the yield and its components. The reproductive stage was clearly more sensitive to drought than the vegetative stage. The cultivar Lee 74 had the highest yield and the second highest yield stress index whereas the cultivar Ra 401 had the lowest yield.  相似文献   
68.
Abstract

Regardless of inoculum or fertility rate Bragg outyielded Clark 63 soybeans. Yields of Bragg and Clark 63 were increased about 1000 kg per ha by treatment with inoculum at the rate of approximately 313, 000 bacteria per seed. At the highest rate of applied N, yields of uninoculated soybeans, were lower than the inoculated soybeans at the lowest applied N rate. Phosphorus fertilizer increased yields at a decreasing rate and yields were decreased at the highest rate of applied P. Potassium fertilizer had a negative effect on soybean yields and did not significantly effect the protein or oil content of soybean seed. With increasing P fertilizer rates, there was a decrease in oil content and in increase in protein content of soybean seed.  相似文献   
69.
Abstract

This research was undertaken on a paleudult soil in southern Brazil, 30° south latitude, to quantify lime and P effect upon soybean (Glycine max (L.) Merrill). A lime x P factorial experience with lime treatments of 0, 0.5, 1, and 2 times SMP interpretation to pH 6.5, and 0, 44, 88, 132, and 176 kg P/ha with 3 replications were installed. The experiment was conducted for 2 years (1973–74, 1974–75), with leaf‐N, P, and K; yield; seed‐N, P, and K; Bray P2 (0.03N NH4F + 0.1N HC1) avail‐able‐P and soil pH measurements completed each year. Data was evaluated with linear, quadratic, logarithmic, polynomial, segmented line, and multiple regression using the coefficient of determination as goodness of fit.

The best model fit between P treatment and Bray P2 available‐P was a quadratic equation; the model between relative yield and Bray P2‐P with 54% of the relative yield attributed to Bray P2 available‐P, a sigmented line. This model indicated point of maximum yield (91% relative yield) was obtained at 7.4 ppm‐P, with no increase in relative yield with increasing levels of soil available‐P. To calculate the P fertilizer necessary to increase available soil‐P to the level of maximum yield of equation Yp = [1639(7.4 ‐ xs)]1/2, where Yp = kg P/ha fertilizer needed; and xs = initial Bray P2 soil available‐P in ppm's. The lime effect upon soil pH was best described as a linear relationship. Yield increase with lime at this site was not significant at the 5% level.

The leaf‐N, P, and K increased significantly with soil available‐P levels. A second degree polynomial with logarithmic function best defined these relationships. The calculated DRIS indices and sum proved useful to evaluate the plant‐N, P, and K balance of each treatment.

Only seed‐P level was directly related to soil available‐P. Both seed‐N and seed‐K were highly correlated with indirect effects of soil available‐P levels.

Results from this study suggest the segmented line model would best interpret soybean yield response to Bray P2 available‐P for this soil. To obtain maximum yield using this model rather than the second degree polynomial would require less fertilizer P. Foliar analyses interpretation confirmed adequate plant‐P level would be supplied for maximum yield at this level of fertilization.  相似文献   
70.
Abstract

A three‐year field study was conducted to determine the influence of irrigation on the nutrition of the “Lee 74” cultivar, a determinate soybean (Glycine max (L.) Merr.). The objectives were to measure seasonal concentrations of N, K, Ca, and Mg in steins, leaves, and pods for soybeans grown on a Crowley silt loam (Typic Albaqualf) and a Kobel clay (Vertic Fluvaquent) under irrigated and nonirrigated moisture regimes. Fluctuations in element concentrations in relation to plant growth stage for irrigated and nonirrigated leaves and stems were modeled using multivariate regression. Elements in the pods as effected by irrigation and growth stage were also compared.

During 1974, a wet year, element concentrations of the leaves, stems, and pods were unaffected by irrigation. In the dry years of 1975 and 1976, significant differences in the concentration of N, K, Ca, and Mg in the plant component parts were found due to irrigation. Generally, element concentrations of stems, leaves, and pods of irrigated plants were greater than those of water‐stressed stems, leaves, and pods at several growth stages. Element concentrations in stems and leaves that were significantly affected by irrigation also were reflected in the pods, Regression models generally accounted for the majority of the seasonal element variation. Irrigation improved the predictability of the K and Ca regression models.  相似文献   
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