共查询到20条相似文献，搜索用时 78 毫秒
1.
2.
3.
4.
覆膜和施肥对玉米大豆间作体系作物氮素吸收和产量的影响 总被引：1，自引：0，他引：1
探究间作下覆膜和施肥对作物产量和氮肥利用率的影响,为旱地栽培增产增效提供依据。本研究采用大田试验,设置4个处理：不覆膜不施肥(non-F+CK)、不覆膜施肥(non-F+NP)、覆膜不施肥(F+CK)和覆膜施肥(F+NP),研究覆膜和施肥对玉米、大豆地上部干物质积累、氮素吸收和产量的影响。结果表明：施肥条件下,覆膜处理玉米和大豆各时期干物质量增加了3.5%～20.3%和24.4%～132.8%,氮素吸收量增加了4.9%～51.7%和10.6%～123.9%,不覆膜条件下玉米和大豆产量分别为9785.8 kg/hm2和1087.5 kg/hm2,覆膜后显著增产10.4%和28.6%(P<0.05);不施肥条件下,覆膜提升了播后66 d和95 d玉米和大豆的干物质量和氮素吸收量,但收获时玉米显著降低了19.3%和25.1%(P<0.05),大豆稍有降低但差异不显著,玉米产量为3102.6 kg/hm2,较不覆膜显著减产30.4%,覆膜对大豆产量影响不显著。覆膜不同程度地提高了玉米和大豆的氮肥利用率,其中玉米的表观... 相似文献
5.
春玉米中单909农艺性状和产量对密植的响应及其在东北不同区域的差异 总被引：8，自引：0，他引：8
增密是实现东北春玉米大面积增产的关键技术,水热和土壤等区域生态条件是决定作物密度高低的关键因素。东北的区域生态条件差异显著, 阐明作物对密度和区域生态条件的综合响应对东北春玉米增密增产具有重要的理论与实践指导意义。本研究以中单909为供试品种, 在代表东北不同生态条件的辽宁沈阳、吉林公主岭、黑龙江哈尔滨、吉林桦甸和吉林洮南等5个试验点设置密度试验, 研究春玉米农艺性状与产量对密度和区域生态条件的综合响应。结果表明, 密植导致株高与穗位高增加, 茎粗降低。区域生态条件主要影响玉米株高, 对茎粗和穗位高的影响不显著。随密度增加, 群体叶面积指数(LAI)显著增加, 尤其是随热量条件改善, 群体LAI呈显著增加趋势。在一定范围内, 密植可以通过提高群体干物质生产力弥补单株生产力的下降, 从而获得高产; 本试验条件下, 中单909在9.00万株 hm-2左右密度下的密植增产潜力得到充分发挥, 而区域间因生态条件不同, 高产种植密度存在显著差异, 其适宜密植范围在8.6~9.6万株hm-2之间。 相似文献
6.
7.
8.
本研究在宁夏引黄灌区生态条件和高水肥生产条件下,以参试的11个玉米品种为研究对象,采用3种种植密度6.6万～7.8万株/hm2,分析不同玉米品种的主要农艺性状、产量水平及生产潜力和不同品种的高产适宜栽培密度。试验结果表明:产量呈现随密度增加而增加的趋势;各密度间的产量构成因素对产量的贡献均表现为收获穗数粒重穗粒数。在宁夏引黄灌区及北方相类似的灌溉春玉米区高产栽培水平下,玉米高产(15000～17250kg/hm2)品种的利用应以耐密植的中棒型、品质好和容重高的品种为第一选择目标。容重值的大小与种植密度的关系不大,生产实践中可将使用容重较高的品种作为重要的增产措施之一。同时建议将容重作为玉米高产品种选育的参考数量指标。 相似文献
9.
10.
密度与施肥对不同玉米品种产量的影响 总被引：1，自引：0，他引：1
为探索适宜普洱地区玉米高产栽培的优化农艺措施,以云瑞47、云优105两个玉米杂交种为材料,研究不同类型玉米品种在不同密度和不同施肥水平下产量的变化规律.结果表明：不同品种产量差异显著,在相同密度和施肥水平上云优105高于云瑞47;云优105栽培密度在82500株/hm2和施肥水平N37 kg/hm2、P2O5 225kg/hm2、K2O270 kg/hm2处理下产量最高;云瑞47栽培密度82 500株/hm2和施肥水平N375 kg/hm2、P2 O5 225 kg/hm2、K2O270 kg/hm处理下产量显著高于其它处理. 相似文献
11.
介绍了运用冷冻干燥技术进行速溶蛋花汤的加工,研究了生产工艺、特点以及影响产品质量的主要因素。试验表明,采用冷冻干燥技术加工的速溶蛋花汤,具有营养丰富、风味独特、方便快捷等特点。 相似文献
12.
DENG Zhao-jing 《保鲜与加工》2005,(1):153-156
A new definition of inertia,i.e. the momentum is the measuring of inertia of matter, is proposed. The article through and etc., subjects, the correctness of the new notion of inertia:The monentum is the measuring of inertia has been demonstrated, and the unsolved contradictions of the traditional definition of inetia. And the mass is the measuring of inertia has been revealed. 相似文献
13.
14.
香蕉是热带亚热带发展中国家重要的粮食作物和碳水化合物来源。但近年来,香蕉生产受到严重的病虫危害。大多数香蕉栽培品种是三倍体,生长周期长,而且不孕。由于没有种子,给繁殖和育种带来一定的困难。遗传转化技术的发展为香蕉品种的改良提供了一种有效的手段。香蕉的遗传转化方法有电激法、基因枪法、农杆菌介导法等。农杆菌介导法的应用是香蕉品种改良的一个重大突破。香蕉遗传转化的外植体也发展到多种,有原生质体,胚性细胞悬浮系,分生组织,以及横切薄片等。近几年,随着分子生物学的发展,出现了转化效率更高,重复性更好的香蕉遗传转化技术。如农杆菌和基因枪结合法,离心辅助农杆菌介导法、真空渗透技术等。这些新技术新方法的出现,必将推动香蕉产业高速发展。 相似文献
15.
基于RS与GIS技术,利用景观生态学理论及景观格局指数对布尔津县土地利用现状进行定量分析。结果显示为：（1）布尔津县以草地、林地为主要景观类型,镶嵌着耕地、水域等景观类型。（2）四个分区（即高山区、丘陵区、平原区、荒漠区）的林地资源组成差异明显,耕地、居民、交通及工矿用地集中分布在丘陵区和平原区（3）从各项指数来看,高山区的多样性指数较低;平原区是受人文因素最多的区域,景观优势度低,各种土地利用类型比例差异不大,有利于生态可持续发展,但要合理的开发利用;荒漠区生态环境相对脆弱,要加强生态环境的保护与改善。通过该研究对布尔津县的土地利用现状作一个了解,为该县乃至整个地区的景观规划和可持续发展战略提供科学依据。 相似文献
16.
17.
18.
Efficiency of water use of early plantings of sunflower 总被引：4，自引：0，他引：4
M. Auxiliadora Soriano Francisco Orgaz Francisco J. Villalobos Elías Fereres 《European Journal of Agronomy》2004,21(4):465-476
Rain fed crop production in Mediterranean environments depends to a large extent on strategies that avoid the intense summer drought. Early plantings of sunflower have given consistently higher yields in such environments, but the basis for such yield increases has not been explored. We conducted two field experiments at Cordoba (Spain) to investigate the effects of an early and a late planting date on the components of water-limited crop productivity; namely, water use (T), water use efficiency (TE) and harvest index (HI) of sunflower. The results were generalized by simulating rain fed sunflower yields, under early (1 January) and late (15 March) plantings, for a 25-year period with the aid of a simulation model of the Ceres type (OILCROP-SUN) which has been validated in Cordoba. Experimental seed yields of early plantings in 1989 and 1996 were 2.0 and 3.0 t ha−1, while late plantings yields were 1.3 and 2.4 t ha−1, for the 2 years. Average simulated yields were 2.7 ± 1.1 and 1.9 ± 0.7 t ha−1 for early and late plantings, respectively. For the 2 years, T of early plantings was higher than that of late plantings, but the response of TE and HI to planting date was not the same in the two experiments. In the simulation exercise, T and TE of early plantings were consistently higher than those of late plantings, while there were no differences in the HI for the two planting dates. We conclude that early plantings of sunflower increase rain fed yields by increasing both T and TE, while the impact of planting date on HI very much depends on the crop water stress pattern, which is quite variable from year to year even in the predictable Mediterranean environment. 相似文献
19.
The cotyledon and hypocotyl of eight varieties of alfalfa( Medicago sativa L. )are used to study the effect of different cultivation procedures and genotypes on embryogenic callus and embryoid induction,plant development and transplant of alfalfa.The varieties of alfalfa with high embryoid induction rate and high differentiation rate are screened. A high frequency regeneration system for alfalfa tissue culture is established:which is benifical to the gene transformation of alfalfa. 相似文献
20.
Based on the relation between the incipient yield pressure and the limit of yielding in cylinder according to the elastic disabled rule, a laboratorial method of determining limit of yielding of material is designed and a set of experimental data were gained by the method. The incipient yield pressure of the cylinder is gained by analyzing the experimental data, and then the limit of yielding is gained. The laboratorial method has a good reliability as the experimental value has a little error to the theory value. It has a definite engineering signification and theory value to research the mechanical capability of material and the disabled rule of high pressure vessel. 相似文献