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小麦不育系BNS在石家庄地区育性转换规律的研究 总被引:1,自引:0,他引:1
2006~2010年在河北省石家庄地区自然条件下,对小麦温敏不育系BNS进行分期播种试验,研究了其在石家庄自然生态条件下的开花习性和育性转换规律。结果表明:播期对BNS育性影响较大,随着播种期的推迟,BNS雄性育性表现为完全败育或高度不育→半不育→完全可育的育性转换规律。BNS在石家庄地区10月9日以前播种,具有稳定的不育期,在此时期制种安全可靠;在11月10日以后播种,具有稳定的可育期,并且自交结实率高,繁殖系数高。 相似文献
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湖北光敏感核不育水稻育性转换机理初探 总被引:4,自引:1,他引:4
用乙烯生物合成抑制剂CoCl_2处理湖北光敏感核不育水稻(HPGMR),可在长日照不育条件下出现可育现象,而在育性转换临界光长下显著促进可育性表达。HPGMR幼穗中乙烯释放量,在长日照下所形成的幼穗比普通农垦58品种高2.5-5倍,而在育性转换临界光长下所形成的幼穗则降低至接近普通农垦58的低水平。表明HPGMR中可能存在受光周期调节的乙烯代谢系统,其育性转换受乙烯代谢水平的调控。 相似文献
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研究青刺果种粕粉对鸡免疫器官及其免疫细胞动态变化的影响。将7日龄鸡分成实验组和对照组,每组设3个重复,对照组饲喂基础日粮,试验组的饲粮中分别添加10g/kg、15g/kg青刺果种粕粉,饲喂30d。第14、21、28日龄时分别取胸腺、法氏囊和脾脏制作切片。测定免疫器官中T淋巴细胞和巨噬细胞数量。实验结果表明,试验组在初期14、21日龄的脾脏、14日龄的法氏囊和28日龄的胸腺中的T淋巴细胞数量较对照组均升高显著(P<0.05或P<0.01);而试验组在后期21、28日龄的法氏囊、14日龄的脾脏和28日龄的胸腺中的巨噬细胞较对照组也同样升高显著(P<0.05或P<0.01)。结果提示,青刺果种粕粉能提高鸡的免疫力。 相似文献
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源库改变对小麦籽粒蛋白质,淀粉含量及产量的影响 总被引:5,自引:0,他引:5
利用蛋白质含量及产量各不相同3个春小麦品种.研究了源库改变对淀粉、蛋白质沉术;及单侏产量的影响.结果表明:源库改变明显地影响着籽粒蛋白质的含量,而对淀粉、可溶性糖含量影响不大;品种间蛋白质含量对源库变化的反应不同;千粒重的增减也因品种而异;淀粉的沉积主要受库的限制,而源库都影响着蛋白含量;旗叶在产量和蛋白形成中起着同样重要作用。 相似文献
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Coastal habitats near urban centres in North Atlantic estuaries often support substantial numbers of wintering waterfowl, but little is known of the effects of landscape setting and urbanisation on habitat use. We conducted surveys of waterfowl at 32 wintering sites in Narragansett Bay, Rhode Island, to identify characteristics that may influence habitat use. Sites were chosen along a gradient of urbanisation and reflected the dominant habitat types used by waterfowl in the Bay. Mean waterfowl abundance was 206.7 ± 209.5 birds per site, and sites in the inner part of the estuary had higher overall waterfowl abundances (r2 = 0.40, p = 0.021). Species richness ranged from 3.2 to 13.0 and decreased with increasing hunting activity (r2 = 0.36, p = 0.040). Hunting activity and habitat characteristics (e.g., latitude, shoreline configuration, prey density) explained 13-27% of the variation in waterfowl abundance and species richness among sites, but landscape characteristics (e.g., surrounding residential development, vegetated land, or wetland surrounding the sites and the extent of wetland edge) explained an additional 1-26%. The landscape characteristics extent of adjacent residential development and vegetated upland were the most common variables entering into the models; most species were more abundant at sites with more adjacent vegetated upland and less adjacent residential development. Our results suggest that landscape setting may be influencing the distribution of wintering waterfowl, and should be considered when developing strategies for the conservation for these species in urban North Atlantic estuaries. 相似文献
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对林权流转的法律属性进行了分析,认为林权流转的法律属性实质上是林业物权的变动而非森林资源的交易;林业物权的变动尤其是指林地与森林资源的使用权的变动;林权流转政策规范的重点在于林地、森林使用权的流转。 相似文献
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Development and validation of numerical indexes integrating enzyme activities of soils 总被引:1,自引:0,他引:1
Three numerical indexes, based on soil enzyme activities, which can discriminate between altered and unaltered soils, are presented and validated. Seven enzymes were measured at three different agricultural sites subjected to contamination by municipal and industrial wastes (site 1), intensive cultivation without either crop rotation or organic fertilization (site 2), and irrigation with brackish water (site 3). At each site neighbouring, unaltered soils were sampled and analysed as control soils.The three indexes were developed by means of canonical discriminant analysis (CDA) using data from two sites, while the third site was kept aside as an independent test. The first index is built up using all of the enzyme activities studied; the second, using the most discriminating enzyme activities only; and the third was developed for testing against data in published papers that deal with enzyme measurements in soils under different management regimes.The three indexes were able to discriminate between altered and control soils when applied to the data set from the third site, i.e., that not used for index development. When tested against published data, the third index was usually able to discriminate altered soils from controls by higher index scores. This index was successful in most cases: it was consistently able to classify soils according to their reported degree of alteration. Our results confirm that enzyme activities are suitable indicators of soil alteration and may be usefully integrated to develop soil alteration indexes suitable for monitoring soil status under different conditions. 相似文献