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91.
[目的]研究草木灰与化肥配施对玉米生长及产量的影响,探讨施用草木灰后玉米生长变化规律,筛选出适宜配比,为农田合理配施草木灰、提高作物产量提供参考。[方法]以玉米为试材,采用田间试验方法,对比草木灰与氮、磷、钾化肥配施,玉米株高、穗长、穗粗、百粒重及产量表现。[结果]草木灰与氮磷肥配施,玉米株高、穗长、穗粗、百粒重及产量均高于氮钾和磷钾配施处理,分别比对照高15.41 cm、1.83 cm、0.48 cm、6.16 g,产量达10 938.85 kg/hm~2,比对照(CK)增产37.91%,比施用氮磷钾化肥增产1.86%。与氮磷钾3种营养元素配施,玉米产量为11 036.35 kg/hm~2,比对照(CK)增产39.14%,比施用氮磷钾不施草木灰处理增产2.77%,两者差异不显著。[结论]草木灰与化肥配合施用,玉米农艺性状表现良好,且能提高产量。玉米田草木灰与氮磷钾化肥配合施用,优选氮肥、磷肥,在农业生产中,可用草木灰替代钾肥与氮磷肥配施,减少无机钾肥的施用量,增加玉米产量。 相似文献
92.
《Communications in Soil Science and Plant Analysis》2012,43(1):73-85
Separation of livestock slurries followed by reverse osmosis yields mineral concentrates (MCs) in which almost all nitrogen (N) is ammonium (NH4)-N. The ability of MCs to substitute calcium ammonium nitrate (CAN), a common conventional mineral N fertilizer, was tested in two trials on a silty loam soil (ware potatoes, 2009 and 2010) and four trials on sandy soils (starch potatoes, 2009 and 2010; silage maize in 2010 and 2011). The N fertilizer replacement value (NFRV) of spring-injected MCs ranged from 72 to 84%, slightly less than their share of ammonium-N (90–100%). The fate of N that was apparently unavailable to crops was not fully disclosed, but there were indications that ammonia loss may have played a role. 相似文献
93.
不同配方施肥对种茧育的影响 总被引:7,自引:0,他引:7
试验结果表明:在有机肥施用量不变的情况下,桑园增施磷钾肥,能极显著地提高种茧的茧质,产卵量及良卵率。 相似文献
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Foliar fertilizers (FF) applied at the reproductive growth stage was reported to increase soybean (Glycine max L. Merr.) yield in field trials. But yield increases have not been consistent. Field experiments were conducted on Calloway silt loam soil in 1981—1982 to determine the effect of two foliar fertilizer (FF) formulations, 16N + 4P + 4K + 1 S (Hanway) and 12 N + 4 P + 4 K + 0.5 S (Folian), and time of application, 0800- and 1900-h, on the growth of seven soybean cultivars from maturity groups V, VI, and VII. Foliar fertilizers were applied at a rate of 187 L/ha?1 in water by a backpack CO2 pressure sprayer at R5 to R6 growth stages. Foliar fertilizers caused no crop injury (leaf burn) when applied at 1900-h but caused moderate injury at 0800-h, which caused a yield reduction. The most significant crop injury was caused by Hanway formulation when applied at 0800-h. Yields were significantly reduced by FF in 1981 but not in 1982. Generally, Folian formulation treatments had higher yields than Hanway formulation treatments, but neither formulation increased yield above that of the untreated plants. The Bragg cultivar exhibited the least amount of crop injury and the most positive yield response to FF. Plant height, 100-seed weight and lodging rates were not adversely affected by the foliar applications. Due to the general lack of consistent yield increases or in some instances yield reduction from FF applications, the formulations used cannot be recommended for use by soybean producers. 相似文献
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98.
配方施肥对洋葱产量与品质的影响 总被引:1,自引:1,他引:0
针对目前生产中不平衡的施肥现状及不完善的栽培技术措施,通过田间试验研究施肥量、栽培定植密度、定植时间对产量与品质的影响,结果表明:对洋葱生产具有主要影响因素的是氮肥施用量,定植密度和钾肥施用量为次主要因素,磷肥施用量是次要因素。氮肥施用量主要对产量以及可溶性糖的含量有影响,要提高这些指标,可在一定范围内增施氮肥。钾肥施用量对维生素C含量影响较大。且在一定程度上呈现出正相关。经综合平衡法分析后,得出最优的栽培措施是氮肥施用量为40kg/667m2,定植密度为15cm×15cm,钾肥施用量为80kg/667m2,磷肥施用量为60kg/667m2。采用此栽培措施,洋葱产量高,品质优。 相似文献
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100.
The effects of nitrogen (N) and phosphorus (P) rates, P source, and method of P application were tested on growth and nutrition of four clones of hybrid poplar (Populus trichocarpa Torr. & Gray×P. deltoides Bartr. ex Marsh or P. trichocarpa×P. maximowiczii A. Henry) in a plantation on Vancouver Island. Treatments were applied shortly after planting. Nitrogen (0, 500kgNha–1) was supplied as ammonium sulfate (AS); half of the AS was added at the start of the second growing season. Phosphorus (0, 100, 200kgPha–1) was supplied as triple super phosphate (TSP), rock phosphate (RP), or diammonium phosphate (DAP) and banded or broadcast. Over four growing seasons, stem volumes increased with AS and P additions. The effects of AS and P each were greatest when the other was also added. Volume was greater when P was applied at 100kgha–1 than in the P control and did not significantly increase further at 200kgPha–1. Phosphorus additions were more effective when added as TSP or DAP than when added as RP, but only in P100 and when banded. Banding increased volume when P was applied at 200kgha–1, but increases were significant only for DAP fertilized trees. Roto-tilling associated with the banding treatment also increased volume when AS and P were not added. Rankings of clones with respect to stem volume varied with N supply and changed over time. 相似文献