共查询到20条相似文献,搜索用时 109 毫秒
1.
杂选1号油菜N、P、K施用量与产量的数学模型研究Ⅱ.中等肥力水平的施肥数学模型建立与施肥决策 总被引:3,自引:2,他引:3
通过杂选l号油菜不同肥力条件下施用氮、磷、钾肥与产量的关系效应研究,获得杂选l号油菜在中等肥力条件下产量与N、P、K三因素的回归数学模型。对模型的分析得出:最高产量施肥量N10.07kg/667m^2.P2O57.678kg/667m^2,K2O10.353kg/667m^2;最适施肥量为N8.654kg/667m^2,P2O56.282kg/667m^2.K2O6.45kg/667m^2,并获得了杂选1号高产150kg以上的优化施肥技术方案。同田对比试验结果,平均产量达175,68kg/667m^2,比农户习惯施肥平均增产30.19kg/667m^2,增产20.75%。 相似文献
2.
氮、磷、钾、硼配合对油菜品种产量、品质的影响 总被引:32,自引:0,他引:32
在湖北省大别山南麓的马肝泥稻田条件下 ,3个不同类型油菜新品种田间试验结果 ,不施肥处理的公顷产量仅 187 5~ 2 6 2 5kg ,施用氮、磷、钾肥增产 7~ 10倍 ,达极显著水平 ;施肥的增产效果杂交双低中油杂 2号大于常规双低中双 4号。 6个不同类型品种盆栽试验结果显示 ,在氮、钾基础上施磷肥苗期干物重增加 8 33~ 14 79倍 ,单株粒重增加 16 5 6~ 6 8 0 0倍 ,不同品种增产率为中双 6号 >中油 82 1>中油杂 2号 >中油杂 1号 >中双 4号 >中双 7号。表明中油 82 1和中双 6号对磷肥反应敏感 ,而中双7号、中双 4号和中油杂 1号较耐低磷 ;不同类型油菜品种施用氮、磷、钾肥均比对照极显著增加植株高度、分枝数、角果数和生物学产量 ;施用氮、磷、钾肥提高菜子中的油脂含量 ,降低蛋白质含量 ,油酸、亚油酸含量增加 相似文献
3.
《(《农业科学与技术》)编辑部》2015,(10)
[目的]研究杂交油菜和常规油菜的氮肥需求差异。[方法]通过2个大田试验(试验1氮肥肥效试验,试验2养分吸收累积规律试验)对比研究了杂交油菜(中油杂5628和中油杂7819)和常规油菜(中双10号)的产量和氮肥利用效率差异。[结果]试验1结果表明,杂交油菜中油杂5628和中油杂7819的产量显著高于常规油菜中双10号,在平台产量分别比中双10号高18.7%和20.2%下,相应的氮肥临界用量低9.5%和9.6%。试验2结果表明,相同氮肥(180 kg/hm2)用量下,中油杂5628和中油杂7819的干物质累积和氮素累积能力高于常规油菜中双10号,这种作用在生育后期表现更为明显。[结论]杂种优势使杂交油菜具有更高的籽粒效率和氮肥利用效率,在相对较少的肥料投入下能获得更高的经济效益。 相似文献
4.
5.
分析了双低杂交油菜华协 1号的杂交制种原理 ,并从选地、整地施肥、精量播种、保苗促壮、防治病虫害、调节花期、严格去杂、砍除父本、收获脱粒、安全贮藏等方面提出了杂交制种技术。 相似文献
6.
7.
8.
9.
10.
11.
Williams JM 《Science (New York, N.Y.)》2002,297(5590):2207-8; author reply 2207-8
12.
Hotspots, basalts, and the evolution of the mantle 总被引:2,自引:0,他引:2
Anderson DL 《Science (New York, N.Y.)》1981,213(4503):82-89
The trace element concentration patterns of continental and ocean island basalts and of mid-ocean ridge basalts are complementary. The relative sizes of the source regions for these fundamentally different basalt types can be estimated from the trace element enrichment-depletion patterns. Their combined volume occupies most of the mantle above the 670 kilometer discontinuity. The source regions separated as a result of early mantle differentiation and crystal fractionation from the resulting melt. The mid-ocean ridge basalts source evolved from an eclogite cumulate that lost its late-stage enriched fluids at various times to the shallower mantle and continental crust. The mid-ocean ridge basalts source is rich in garnet and clinopyroxene, whereas the continental and ocean island basalt source is a garnet peridotite that has experienced secondary enrichment. These relationships are consistent with the evolution of a terrestrial magma ocean. 相似文献
13.
Climate change, deforestation, and the fate of the Amazon 总被引:4,自引:0,他引:4
Malhi Y Roberts JT Betts RA Killeen TJ Li W Nobre CA 《Science (New York, N.Y.)》2008,319(5860):169-172
The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. Here, we summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia. We also discuss the implications of new proposals to finance preservation of Amazonian forests. 相似文献
14.
Lunine JI 《Science (New York, N.Y.)》1993,261(5122):697-698
15.
16.
Snyder CS 《Science (New York, N.Y.)》2001,292(5521):1485-1486
17.
There is growing evidence that the neuropeptides oxytocin and vasopressin modulate complex social behavior and social cognition. These ancient neuropeptides display a marked conservation in gene structure and expression, yet diversity in the genetic regulation of their receptors seems to underlie natural variation in social behavior, both between and within species. Human studies are beginning to explore the roles of these neuropeptides in social cognition and behavior and suggest that variation in the genes encoding their receptors may contribute to variation in human social behavior by altering brain function. Understanding the neurobiology and neurogenetics of social cognition and behavior has important implications, both clinically and for society. 相似文献
18.
Dean RB 《Science (New York, N.Y.)》1986,233(4762):404
19.
Gideonse HD 《Science (New York, N.Y.)》1968,162(3853):541-545
20.
Kerr RA 《Science (New York, N.Y.)》1981,212(4500):1258