Effect of nitrogen,phosphorus and potassium on yields and nutrient levels in carrots grown on sphagnum peat and mineral soils.

Abstract

Carrots, Daucus carota L., were grown on both sphagnum peat and mineral soils from 1969 to 1972 inclusive. Fertilizer treatments consisted of three rates of N, of P and of K applied in all possible combinations.

In practically every instance rates of N, P and K applied to sphagnum peat were reflected in the levels of these nutrients found in carrot leaves. This was not the case with mineral soils. On sphagnum peat there were eight opportunities, and on mineral soils seven, for each of the three applied nutrients to influence yields. On peat N increased yields in three instances, P in one and K in five. On mineral soils N decreased yields in two instances, P decreased them in one and increased them in one while K had no effect.

The results suggest that on sphagnum peat carrots may require N, P and K up to 250, 50 and 150 kg/ha respectively whereas on mineral soils maximum rates would be 25, 25 and 50 kg/ha.     

Effect of nitrogen,phosphorus and potassium on yields and nutrient levels in cabbage grown on sphagnum peat

Abstract

Fertilizer treatments for cabbage, grown on sphagnum peat, consisted of an N, a P and a K series. Each nutrient was applied at four rates in combination with constant rates of the other two.

Results indicated that 270 kg N/ha, the highest rate used, may not have been adequate whereas P and K at 80 and 150 kg/ha respectively were. In the N, the P, and the K series, highest head weights coincided with midribs containing 2.06% N, 0.48% P and 4.18% K respectively.     

钙质紫泥田水稻氮磷钾施肥效应研究

研究了钙质紫泥田水稻氮磷钾的施肥效应,分析了肥料的因素效应及合理施用量。结果表明:(1)在试验施肥量范围内,水稻产量与肥料用量呈二次多项式函数关系;(2)磷和氮的效应高,钾肥效应低;(3)棕紫泥夹砂田水稻合理施肥量为每公顷N 125~130 kg、P2O570 kg、K2O 0~30 kg,下湿紫泥田为N 85~90 kg、P2O555 kg、K2O 0~20 kg;(4)地下水位高、湿害严重,是下湿紫泥田生产水平低、施肥效果差的根本原因,改造途径是深沟排水、脱潜治理。     

Effect of nitrogen,phosphorus and potassium on yields and nutrient levels in onions grown on a sphagnum peat soil

Abstract

Onions were grown on two areas of sphagnum peat. One (old area) had been fertilized and cropped for a 5‐year period and the other (new area) had not. Fertilizer treatments on both areas consisted of an N, a P and a K series. Each nutrient was applied at four rates in combination with constant rates of the other two.

In practically all instances comparable treatments resulted in lower N, P and K levels in plant tissue samples from the new area than from the old where residual effects from previous cropping and fertilization were evident. Yield data indicate that initially, previously unfertilized sphagnum peat should receive N, P and K at 275–300, 40–50 and 70–80 kg/ha respectively.     

芋对氮磷钾吸收分配规律的研究

芋幼苗期对氮磷钾的吸收较少,发棵期和球茎膨大期吸收速率迅速增加,球茎膨大后期吸收积累速率又有所下降。总的来说,芋植株对钾的吸收最多,氮次之,磷最少,全生育期对氮磷钾的总吸收比例为1∶0.28∶1.1。幼苗期和发棵前期氮磷钾主要分布在叶片和叶柄中;其中,氮以叶片中居多,而磷和钾则以叶柄中居多。发棵后期和球茎膨大期主要分配在芋球茎中,其中氮磷的分配率为子芋大于孙芋,而钾则是孙芋中分配多于子芋。     

Effect of nitrogen sources on cassava yields in Sierra Leone

Abstract

Two experiments were conducted on Njala upland soils to investigate the effects of various N sources on cassava. Highest utilization indices (UI) were observed when (NH.)‐SO, and urea were applied in three split applications. Utilization indices of ‘cocoa’ cassava remained below unity indicating that it is a low yielding cultivar since high yielding cultivars have UI near or greater than unity. Application of various N sources did not increase fresh tuber yield in either experiment indicating that under conditions of this study cocoa cassava has a low N requirement.     

Effect of inoculum,variety, nitrogen,phosphorus, and potassium on yield,protein and oil content of soybeans at jabalpur,M.P. India

Abstract

Regardless of inoculum or fertility rate Bragg outyielded Clark 63 soybeans. Yields of Bragg and Clark 63 were increased about 1000 kg per ha by treatment with inoculum at the rate of approximately 313, 000 bacteria per seed. At the highest rate of applied N, yields of uninoculated soybeans, were lower than the inoculated soybeans at the lowest applied N rate. Phosphorus fertilizer increased yields at a decreasing rate and yields were decreased at the highest rate of applied P. Potassium fertilizer had a negative effect on soybean yields and did not significantly effect the protein or oil content of soybean seed. With increasing P fertilizer rates, there was a decrease in oil content and in increase in protein content of soybean seed.     

氮、磷、钾肥配施对紫花苜蓿产量及营养物质含量的影响

2008年在内蒙古西辽河平原灰色草甸土上,采用"3414"二次回归最优设计试验方案,研究施肥对不同品种紫花苜蓿的产量效应及营养物质含量的影响。研究结果表明,紫花苜蓿产量最高的施肥方案为N 0 kg/hm2、P2O5 63.56 kg/hm2、K2O 110.00 kg/hm2,并筛选出WL-232HQ为适宜通辽地区种植的最佳苜蓿品种。同时分析不同施肥水平对紫花苜蓿营养物质含量的影响,14个处理组合中,处理N0P2K2、N1P1K2、N2P2K0、N2P1K2和N2P2K3是试验条件下获得粗蛋白含量较高的组合。     

设施栽培番茄的氮磷钾肥料效应研究

采用"3414"肥料试验设计开展了设施栽培番茄的氮、磷、钾肥料效应研究。结果表明,在高肥力土壤上适量施用氮、磷、钾肥均可增加番茄产量,但过量施用会降低其产量;钾肥的增产作用大于磷肥,氮肥的作用较小;氮、钾肥和磷、钾肥配施可增加番茄产量,而氮、磷肥配施降低产量。氮、磷(P_2O_5)和钾(K_2O)最佳经济施肥量分别为119.0、50.4和375.6 kg/hm~2,施肥比例为1∶0.42∶3.16。不同施氮量对番茄硝酸盐和亚硝酸盐含量的影响不规律,增施磷、钾肥番茄硝酸盐含量呈先增加后减少趋势;氮、磷肥和磷、钾肥配施可降低番茄硝酸盐和亚硝酸盐含量。氮、钾肥和磷、钾肥配施提高了番茄可溶性糖含量,氮、磷肥和磷、钾肥配施降低了番茄总酸含量,氮、钾肥配施则有增加番茄总酸含量的趋势,氮、钾肥和磷、钾肥配施均可提高番茄Vc含量。氮、磷、钾肥料合理配施对番茄产量和品质的提高具有重要作用。     

甘薯氮磷钾肥平衡施用效应分析

本文运用311-A拟饱和最优回归设计,在沿海赤砂土甘薯主产区设置晚薯施用氮磷钾肥料试验,模拟出甘薯薯块产量和施肥利润的氮磷钾肥料效应函数,通过极值判别均为典型函数,用边际分析寻优,获得甘薯薯块最高产量和最高施肥利润的优化施肥组合分别为:Zmax为Z1=N136 25kg/hm2,Z2=P2O552 71kg/hm2,Z3=K2O275 68kg/hm2,薯块产量最高,^ymax=39 214t/hm2;Zopt为Z1=N117 09kg/hm2,Z2=P2O546 24kg/hm2,Z3=K2O247 01kg/hm2,施肥利润最佳为^πopt=18298 99元/hm2。     

Influence of nitrogen,phosphorus, and potassium fertilization on the mineral concentrations in Medicago sativa L. I. Seasonal changes

Abstract

An established stand of Ranger alfalfa was topdressed with equal rates, but different combinations, of N, P, and K. Five harvests were taken and the material analyzed for cation concentrations.

Phosphorus application significantly increased P concentrations in alfalfa, but had little influence on concentration of other ions. Potassium applications showed striking effects by significantly increasing K levels of the forage while decreasing Ca, Mg, Cu, Zn, Al, and Mo levels.

Significant differences occurred among harvest dates for 14 of the 16 cations analyzed. Seasonal trends were evident for SiO₂, Zn, Al, Co, and Na.

Applied N, P, and K and available soil P and K were associated with cation concentration of alfalfa and these interrelationships are discussed.     

茶树工厂化育苗的氮磷钾肥施用效应分析

应用311-A最优回归设计方法,研究了冬季施用氮、磷、钾对于工厂化育苗条件下茶苗生长的影响,建立了施肥与茶苗生长过程中株高变化的多项式回归模型,并且寻求出其最佳用量方案。当N=185.7 kg/hm2,P2O5=239.8 kg/hm2,K2O=0.0 kg/hm2,株高的最大增加量预计为8.3 cm。     

有机肥料氮、磷、钾的化学分析方法

介绍了用化学分析方法测定有机肥料氮、磷、钾的含量，即样品经硫酸一过氧化氢消化后，制备待测溶液，分取待测溶液用NC-2型快速定氮仪测定氮，用磷钼酸喹啉重量法测定磷，用四苯硼酸钾重量法测定钾，不须使用分光光度计和火焰光度计，适宜一般复混肥料厂采用，对含氮、磷、钾分别达0．1％以上的样品均可用本法测定，方法的准确度和精密度能满足生产的要求。     

Influence of nitrogen,phosphorus, and potassium fertilization on the mineral concentrations of medicago sativa L. II. Diurnal and day to day fluctuations

Abstract

An established stand of alfalfa was fertilized with different combinations of N, P and K. The rate used per nutrient was constant for all combinations. The study was conducted to evaluate the effect of fertilizer application, diurnal change and period to period fluctuation on the mineral composition of alfalfa. Two experiments were conducted at different stages of morphological maturity. Experiment one (E‐1) was initiated when regrowth after an initial hay harvest was in the late‐vegetative to early‐bud stage. The second experiment (E‐2) was initiated when regrowth from E‐1 was approximately 20 cm tall.

Phosphorus application significantly increased the P concentrations in alfalfa, but decreased the Cu levels in both experiments. Potassium applications significantly decreased the levels of Ca, Mg, Na, Cu, Zn, Mo and Co.

Levels of all minerals analyzed in E‐1 were significantly different from period to period while only seven of the sixteen were significantly changed in E‐2. Period to period differences were partially explained by rainfall pattern.

Significant diurnal variations were found for K, Ca, Mn, B, Sr, and Zn in E‐1 and for Ca, SiO₂, and Sr in E‐2.

The N, P, and K applied and the P and K available in the soil were correlated with cation levels in alfalfa and the interrelationships were discussed.     

Effect of fall tillage following soybeans on organic matter losses in snowmelt

In a corn–soybean rotation, maintaining crop residue on the soil surface is a challenge following soybeans. Often farmers are encouraged not to till the soil following a soybean crop in order to maximize the amount of residue at the soil surface. In this study we evaluated the effect of this practice compared to fall moldboard plowing on snowmelt runoff and losses of total solids (TS) and organic carbon (using oxygen demand in runoff as a surrogate). A paired watershed approach was used to evaluate the effect of these management practices. Individual hydrographs were compared and contaminant losses in runoff calculated. Results show that snowmelt runoff and the associated losses of total solids, chemical oxygen demand (COD), and biochemical oxygen demand (BOD) were less with fall moldboard plowing compared to no fall tillage following soybean (0.22 cm, 1.9 kg ha⁻¹, 0.81 kg ha⁻¹, 74 g ha⁻¹, reduction in median value per melt cycle, respectively). In areas where snowmelt runoff is an important component of annual runoff, some tillage in the fall would be preferable to no-tillage in order to reduce snowmelt runoff losses.     

Effect of nitrogen levels and coated urea on growth,yields and nitrogen use efficiency in aromatic rice

Results from a field experiment conducted at the Indian Agricultural Research Institute, New Delhi, India showed that coating urea with elemental sulfur or gypsum or phosphogypsum gave higher yields (12.08, 6.78 and 6.14% higher grain yield compared to prilled urea) of high yielding an aromatic rice cultivar ‘Pusa Sugandh 5’ (Pusa 2511) and increased the efficiency of prilled urea. As regards nitrogen use efficiency sulfur coated urea was nearly twice as effective as gypsum or phosphogypsum coated urea; the latter two were equally effective compared to prilled urea alone.     

冻融循环对典型地带土壤速效氮磷及酶活性的影响

为了探寻冻融循环次数和冻结温度对典型地带性土壤（黑土、潮土、黄土）养分形态和酶活性的作用机制,应用室内冰柜模拟不同冻结温度（-20℃强冻和-10℃弱冻）,以及不同的冻融循环次数（1次和2次）。结果表明,经过冻融循环3种土壤NO3--N含量增加,增加量趋势为黄土＞潮土＞黑土,与冻结前相比黄土和潮土NO3--N含量分别达到5%显著水平;冻融循环3种土壤NH4+-N含量减少,减少量趋势为黑土＞黄土、潮土;黑土速效磷含量显著增加（P<0.05）;冻融循环增强了过氧化氢酶活性,却降低了脲酶活性;冻结温度对耕作土壤速效养分和酶活性影响不显著。建议耕作潮土和黄土应考虑冻融循环后养分总量,从而适当调整氮肥投入。     

In vitro growth of Nidularium minutum mez (Bromeliaceae) in different concentrations of nitrogen,phosphorus, potassium,and calcium

Nidularium minutum Mez is a terrestrial bromeliad with ornamental potential, especially as a species that develops the shade. This, as well as many other bromeliads, is endangered. We studied the growth of nitrogen (N). N. minutum cultured in vitro in different concentrations of nitrogen (N), phosphorus (P), potassium (K), or calcium (Ca) to develop an ideal growth environment for this plant to preserve the species. Results favorable to the growth were treatments containing 60 mM N, 0.60 and 1.25 mM P, 10 mM K, and 1.5 mM Ca. Based on these results two new culture media were prepared (T1 and T2) and were compared with the MS medium with dilutions of macronutrients (50%, 20%, 10%, and 5%). The results showed that changes in the MS medium favored growth of N. minutum.     

连续种植蔬菜对潮土磷素水平的影响

Soil P status, inorganic P fractions, and P sorption properties were studied using sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetable production in comparison with a soil used for grain crop production in Zhengzhou, Henan Province, China. P fractions, Olsen-P, and OM were determined at different depths in the soil profile and sorption isotherm experiments were performed. Most P in excess of plant requirements accumulated in the topsoil and decreased with soil depth. Total P, inorganic P, and OM concentrations increased with continued horticultural use. Olsen-P concentrations in the 0-20 cm depth of horticultural soils were 9 to 25 times higher than those of the grain crop soil. A linear transformation of the Langmuir equation showed that the P adsorption maximum (491.3 mg P kg^-1) and the maximum phosphate buffering capacity (162.1 L kg^-1) for 80-100 cm were greater in the grain crop soil than the horticultural soils. Thus, the most immediate concern with excess P were in areas where heavy P fertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandy soils and high organic matter content.