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971.
《Plant Production Science》2013,16(4):331-337
AbstractDays from full maturity to combine harvest maturity (DFC) is a major concern in combine harvesting of soybeans (Glycine max (L.)), especially in northern Japan, which has a short harvesting period. The combine harvest maturity, which was defined as the day at which the moisture content of the stem reached 30%, was analyzed using 7 soybean varieties for 3 yr in Hokkaido. There were significant differences in DFC among varieties (12 to 31 d) and among the 3 yr (16 to 25 d). DFC was closely associated with dry matter partitioning to stem (DMPS) at full maturity, that is, high DMPS increased DFC. The relationship between DMPS and DFC was examined by pod removal experiments conducted for 2 yr. In the soybean plants with high DMPS pod removal increased the stem desiccation period and DFC. These results indicated that DMPS at full maturity is an informative indicator for predicting the harvest maturity in the combine harvesting system. 相似文献
972.
以大豆分离蛋白为试验材料,优化糖基化大豆分离蛋白制备工艺并研究经过葡萄糖处理对大豆分离蛋白溶解度、凝胶强度、乳化性以及热稳定方面的影响。结果表明:糖基化大豆分离蛋白最佳制备工艺为反应温度69.49℃、反应时间46.64 min、糖的添加量10.64%,凝胶强度最高为76.03;在相同p H下,经葡萄糖处理后的大豆分离蛋白溶解度较大,沉淀较少,而未糖基化的大豆分离蛋白沉淀量增加。糖基化处理的大豆分离蛋白乳化稳定性(emulsifying stability,ES)和热稳定性均有所增强。糖基化改性过程可显著提高大豆分离蛋白的溶解性和乳化性能,这为拓宽其在食品工业中的应用提供了理论基础。 相似文献
973.
《Communications in Soil Science and Plant Analysis》2012,43(9):1219-1232
Abstract Bragg soybeans [Glycine max. (L. ) Merill] were grown under field conditions near Sanford, Florida on a tile‐drained Immokalee fine sand (sandy, siliceous, hyperthermic Arenic Haplaquod). The objectives were: 1) to assess the K and P fertilizer requirements of soybeans grown in central Florida 2) to correlate soil and tissue nutritional levels with extractable soil nutrients and 3) to assess the influence of K application time on yield. Experimental treatments were four K rates (0, 50, 100, and 200 kg K/ha), three P rates (0, 25, and 50 kg P/ha), and two sidedress K rates (0 and 50 kg K/ha) at early bloom. Treatments were arranged in a randomized complete block design and replicated four times. Yield increased with each increase in applied K. Statistical maximum yield was obtained on plots which contained 103 ppm double‐acid extractable K during the pod‐filling stage of growth. Tissue K at early bloom exceeded 2.85% at maximum statistical yield. Potassium applied broadcast at early bloom did not significantly influence yield. This soil contained approximately 390 ppm double‐acid extractable P prior to P application. No significant yield response to applied P was observed, indicating that the original extractable P content of the soil was adequate for the yield level obtained. The quadratic regression of the ratio equivalents of double‐acid extractable K:Ca + Mg on the same ratio for the plant tissue is highly significant. This expression was a good predictor of tissue accumulation of these nutrients in that the coefficient for determination was 0.68. 相似文献
974.
975.
976.
《Plant Production Science》2013,16(4):374-382
AbstractSoybean yield is low in the fields with a low groundwater level during summer due to drought stress. By raising the groundwater level using Farm-Oriented Enhancing Aquatic System (FOEAS) the yield of soybean cultivar Sachiyutaka can be increased, but not that of Fukuyutaka. Here, we examined the effect of the groundwater level on root growth and its dynamics in these two cultivars. Three of the four experiments demonstrated that root elongation ceased just below groundwater level in both cultivars. However, when the groundwater level was kept at 35 cm or deeper, the root growth at an early growth stage was more vigorous at a deeper layer in Fukuyutaka than in Sachiyutaka, but at the mid-growth stage root growth in Sachiyutaka became similar to or exceeded that of Fukuyutaka. These results indicated that the optimum control technique for the groundwater level differed with the cultivar. The groundwater level for Sachiyutaka should be kept relatively high at an early growth stage. Further studies will be needed to clarify the optimum control technique for maximizing the yield of Fukuyutaka that have a fast root growth at an early growth stage. 相似文献
977.
A new strain of Tobacco mosaic virus (TMV) was isolated from soybean (Glycine max) in India (TMV-SoyIn). It produced puckering symptoms on inoculated soybean cultivars, JS-20-30 and JS 93-05, and severe necrotic spots on inoculated leaves of Nicotiana tabacum cv. Xanthi, followed by systemic necrotic spots on subsequent leaves as well as greenish mosaic symptoms on the top leaves. In the electron microscope, tobamovirus like particles were observed in soybean leaves and also in the other inoculated host plants. The host reactions revealed that the present isolate was different from the previously described TMV strain of soybean (TMV-S) from Yugoslavia. To confirm the virus identity, the 3′ end of the genome containing the movement protein gene, coat protein and the 3′ untranslated region of the virus isolate was sequenced (1494 nucleotides; JQ895560). Results indicated that the virus associated with soybean crinkle was an isolate of TMV as the present isolate had 94.4–99.7% sequence identity with known TMV isolates. This is the first report of a TMV-strain infecting soybean in India. 相似文献
978.
为明确大豆菌核病发生发展中各个时期气象因子的重要性及相关性,对黑龙江省大豆主产区中9个地点的大豆田菌核病病情指数进行调查,收集各地6~8月的平均降水量、平均日照时数和平均气温,在此基础上采用多元回归分析的方法建立回归方程,然后利用通径分析确定影响菌核病发生的主要气象因子。结果表明:8月份平均降水量对大豆菌核病病情指数的影响最为严重,其次为7月份平均日照时数和8月份平均温度;7月份平均日照时数是通过与8月份平均降水量相互作用对大豆菌核病的病情指数产生较大影响。其它因子的直接间接通径系数都很低,对菌核病病情指数的影响不大。因此,在7月份的平均日照时数少,8月份平均降雨量大,并且8月份平均温度适宜的情况下菌核病将发生流行。 相似文献
979.
980.
《Journal of plant nutrition》2013,36(7):1383-1402
Abstract Narrow‐row soybean [Glycine max (L.) Merr.] production in corn [Zea mays L.]–soybean rotations results in various distances of soybean rows from previous corn rows, yet little is known about soybean responses to proximity to prior corn rows in no‐till systems. The objective of this study was to evaluate the impacts of preceding corn rows on potassium (K) nutrition and yield of subsequent no‐till soybeans. Four field experiments involving a corn–soybean rotation were conducted on long‐term no‐till fields with low to medium K levels from 1998 to 2000 near Paris and Kirkton, Ontario, Canada. In the corn year, treatments included K application rate and placement in conjunction with tillage systems or corn hybrids. Before soybean flowering, soil exchangeable K concentrations (0–20 cm depth) in previous corn rows were significantly higher than those between corn rows. At the initial flowering stage, trifoliate leaf K concentrations of soybeans in preceding corn rows were 2.0 to 5.3 g kg?1 higher than those from corresponding plants between corn rows. Yield of no‐till soybeans in previous corn rows increased 10 to 44% compared to those between previous corn rows. Positive impacts of prior corn rows on soil K fertility, soybean leaf K, and soybean yield occurred even when K fertilizer was not applied in the prior corn season. Deep banding of K fertilizer tended to accentuate row vs. between‐row effects on soybean leaf K concentrations in low‐testing soils. Corn row effects on soybeans were generally not affected by either tillage system or corn hybrid employed in the prior corn crop. Potassium management strategies for narrow‐row no‐till soybeans should take the potential preceding corn row impacts on soil K distribution into account; adjustments to current soil sampling protocols may be warranted when narrow‐row no‐till soybeans follow corn on soils with low to medium levels of exchangeable K. 相似文献