Sugar beet yield and industrial sugar contents improved by potassium fertilization under scarce and adequate moisture conditions

Sugar beet（Beta vulgaris L.） is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet cultivation. Beet sugar contents are higher than sugarcane sugar contents, which can be further increased by potassium（K） fertilization. Total K concentration is higher in Pakistani soils developed from mica minerals, but it does not represent plant available K for sustainable plant growth. A pot experiment was conducted in the wire-house of Institute of Soil and Environmental Sciences at University of Agriculture Faisalabad, Pakistan. K treatments were the following： no K（K_0）, K application at 148 kg ha^（–1）（K_1） and 296 kg ha^（–1）（K_2）. Irrigation levels were used as water sufficient at 60% water holding capacity and water deficient at 40% water holding capacity. The growth, yield and beet quality data were analyzed statistically using LSD. The results revealed that increase in the level of K fertilization at water sufficient level significantly increased plant growth, beet yield and industrial beet sugar content. The response of K fertilization under water deficient condition was also similar, however overall sugar production was less than that in water sufficient conditions. It is concluded from this study that K application could be used not only to enhance plant growth and beet yield but also enhance beet sugar content both under water-deficient as well as water-sufficient conditions.

水钾耦合对南疆滴灌枣树叶片生理特征及产量的影响

【目的】探究南疆滴灌枣树最优灌溉施肥制度,提高南疆特色林果种植业生产效益。【方法】以阿克苏地区典型果树—8 a生灰枣为研究对象,于2022—2023年开展灌水量与施钾量的二因素三水平全面试验(灌溉水平为T1:ETc,T2:75%ETc,T3:50%ETc;钾肥水平为A:240 kg/hm^(2),B:180 kg/hm^(2),C:120 kg/hm^(2)),探究灌水量与施钾量对枣树光合特征及产量影响。【结果】灌水量和施钾量对枣树生长发育影响显著,枣树净光合速率和蒸腾速率、叶绿素量会随灌水量和施钾量增加而逐渐提高。增施钾肥对枣树叶片可溶性糖量影响显著,2023年T1-A、T2-A、T3-A处理可溶性糖量较2022年增加了37.0%、36.9%、28.7%;而枣树叶片脱落酸(ABA)量受灌水量影响显著,其中T3-C处理ABA量最高。各处理枣树的瞬时水分利用效率(iWUE)随生育期推进多呈逐渐上升趋势,枣树产量也随施钾量增加而上升;施钾量为240 kg/hm^(2)时,2022年,T1、T2处理枣树产量较T3处理增加了56.77%、45.52%;2023年,T1、T2处理枣树产量较T3处理增加了51.46%、37.61%;其中2022、2023年T2-A处理水分利用效率(WUE)分别为8.88、9.14 kg/(hm^(2)·mm)。【结论】本试验条件下,T2-A处理是适宜南疆地区枣树生产效益的灌溉施肥制度。

Sunflower response to potassium fertilization and nutrient requirement estimation

Field experiments were conducted in oil and edible sunflower to study the effects of potassium(K) fertilization on achene yield and quality, and to estimate the nutrient internal efficiency(IE) and nutrient requirement in sunflower production. All trials in edible sunflower and 75% trials in oil sunflower showed positive yield responses to K fertilization. Compared with control without K fertilization, the application of K increased achene yield by an average of 406 kg ha–1for oil sunflower and 294 kg ha–1for edible sunflower. K application also increased 1 000-achene weight and kernel rate of both oil and edible sunflower. K fertilization improved the contents of oil, oleic acid, linoleic acid and linolenic acid in achenes of oil sunflower, and increased contents of oil, total unsaturated fatty acid and protein in achenes of edible sunflower. The average agronomic efficiency of K fertilizer was 4.0 for oil sunflower and 3.0 kg achene kg–1K2O for edible sunflower. The average IE of N, P and K under balanced NPK fertilization was 22.9, 82.8, and 9.9 kg kg–1for oil sunflower, and 27.3, 138.9, and 14.3 kg kg–1for edible sunflower. These values were equivalent to 45.5, 14.1, and 108.1 kg, and 39.0, 8.0, and 71.7 kg of N, P and K, respectively, in above-ground dry matter required for production per ton of achenes. The average harvest index of N, P and K was 0.47, 0.56 and 0.05 kg kg–1in oil sunflower, and 0.58, 0.58 and 0.14 kg kg–1in edible sunflower.

Effect of Potassium Levels on Growth and Productivity of Potato Varieties

Potato is one of the priority vegetable crops in the highlands of Eritrea growing as a key component in the livelihood systems of farmers. Potato requires a variety of balanced plant mineral nutrients for growth and development without which yield and qualities of tubers are reduced. Potato growers in Eritrea commonly use Di-ammonium Phosphate, Urea and Farmyard manure while potassium fertilizers are overlooked assuming that the soil is developed from K rich parent material and contains sufficient amount of K to support crop growth. However this assumption is based on the result obtained forty-seven years ago. As a result the yield and quality of potato produced is very low as compared with international standards. Therefore the present experiment was conducted to assess the effect of potassium levels on growth and productivity of potato varieties at Hamelmalo Agricultural College, Eritrea. The experiment was conducted in factorial Randomized Complete Block Design with fifteen treatment combinations of three varieties (Ajiba, Zafira and Picasso) and five potassium levels (0, 75, 150, 225 and 300 kg K2O/ha) replicated thrice. The results of the study showed that both variety and potassium had significant effect on growth and yield parameters. Aerial stem number, leaf number per plant and plant height were increased with increasing K levels from 0 to 150 kg while number of days to maturity was increased in the range of 0 - 300 kg K2O/ha. The result also indicated that variety Ajiba treated with 300 kg K2O/ha produced significantly highest tuber weight (1.14 kg) per plant and tuber yield of 49.38 t/ha. The economic analysis result revealed that maximum gross margin 13,665.816 USD/ha was obtained from the application of 300 kg K2O/ha. On the whole, it gives an impression that using potassium fertilizer according to soil requirements will have good influence on growth and tuber yield.

Effects and Mechanisms of P and K Nutrients on Yield and Protein Content of Fodder Rice

Effects and mechanisms of P and K nutrients on yield and protein content of Weiyou 56, a fodder hybrid rice combination,were studied through pot experiment and biochemical analysis. The results showed that the increase of P and K nutrients enhanced the activities of PEP carboxylase (PEPC), glutamine synthase (GS) and sucrose phosphate synthase (SPS) in leaves, sucrose synthase (SS), ADP glucose pyrophosphorylase (ADPGP) and GS in grains, and the chlorophyll content in leaves, soluble sugar and starch content in grains, protein N and total N content in leaves and grains. Howerer, they decreased soluble sugar content in leaves and led to an increase of protein content in brown rice, biomass, grain yield and harvest index. Excessive P nutrients slightly reduced SPS and ADPG activity in leaves and grains respectively.

氮、磷、钾配施对葛根生长及品质的影响

为探明氮、磷、钾肥配施对葛根生长及品质的影响,为葛根高效栽培提供合理的施肥技术支撑和理论依据,采用L_(9)(3~4)正交试验设计,研究氮、磷、钾配施对葛根产量和主要功能成分的影响,明确研究区葛根氮、磷、钾的最佳施用量。结果表明,不同施肥方案对葛根产量和功能成分的影响显著,其中以N_(3)P_(1)K_(2)(N 270kg/hm^(2),P_(2)O_(5)45 kg/hm^(2),K_(2)O 90 kg/hm^(2))处理的产量和总黄酮含量最高,分别为2.13 kg/株和83.10 mg/g;N_(1)P_(3)K_(2)(N 90 kg/hm^(2),P_(2)O_(5)135 kg/hm^(2),K_(2)O 90 kg/hm^(2))的葛根素含量最高,为24.85 mg/g,N_(1)P_(2)K_(3)(N 90 kg/hm^(2),P_(2)O_(5)90 kg/hm^(2),K_(2)O 135 kg/hm^(2))处理的大豆苷和大豆苷元含量均为最高,分别为22.96和2.55 mg/g。氮、磷、钾肥配施对葛根产量和葛根素含量影响的大小顺序为氮肥>钾肥>磷肥。以葛根产量为目标的最佳施肥量为N 270 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2),以葛根品质提升为目标的最佳施肥量为N 180 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2)。

Effect of Fertilizer Application on the Yield of Walnut (Juglans regia L.)

[Objectives] This study was conducted to explore the fertilization ratio of walnut, so as to provide a basis for rational fertilization of walnut. [Methods] Under the condition of gravelly yellow soil in Chaotian District, Guangyuan City, the orthogonal design of L_9(3~4) was used to test the fertilization ratio of nitrogen, phosphorus and potassium fertilizers. [Results] The effects of nitrogen, phosphorus and potassium fertilizers on walnut yield ranked as phosphate fertilizer>potassium fertilizer>nitrogen fertilizer. The different treatments had great effects on the yield of walnut, and for the land with gravelly yellow soil, the suitable annual fertilization amount of walnut was urea 1 200 g/plant + calcium superphosphate 1 500 g/plant + potassium sulfate 940 g/plant. [Conclusions] This study provides a theoretical basis for rational fertilization of walnut in Sichuan Province.

Evaluation of Soil Potassium Test to Improve Fertilizer Recommendations for Corn

The soil potassium (K) test methodology is under increased evaluation due to the soil sample drying effect, temporal variations of test results and inconsistent crop response to applied K fertilizers. Ten on-farm trials were conducted in 2014 in eastern North Dakota to determine the corn response to different K-fertilizer rates and to assess the variation of soil K test levels between air-dried (KDry) and field moist (KMoist) soil samples during the corn growing season. Significant differences were observed between KDry and KMoist soil K test results. The ratio of KDry/KMoist showed high correlation with cation exchange capacity (r = 0.63, p < 0.10), Organic matter (r = 0.61, p < 0.10) and (Ca + Mg)/K ratio (r = 0.64, p < 0.10) from the 1 M ammonium acetate extractant, while pH, electrical conductivity, clay (%), and soil moisture showed non-significant correlation. On average, KDry resulted in higher soil K test levels than KMoist and pattern of deviation was different for surface and sub-surface soil samples. Soil K analysis of samples collected during the fall and spring showed large enough variations to affect the soil test interpretation category which was used to make fertilizer recommendations. Corn yield increased significantly with applied K fertilizer at only three out of 8 sites with beginning K levels below the current critical level of 150 ppm, and one response was at a site with K level above the critical level. Therefore, use of either the KDry or KMoist method alone may not be adequate to predict K response in some North Dakota soils.

Influence of Nitrogen-Potassium Fertilizers on the Growth and the Productivity Parameters of Plantain Banana PITA 3, FHIA 21 and CORNE 1

This study was undertaken to measure the impact of fertilizers (nitrogen-potassium) on the growth and the development of plantain banana. Different doses of fertilizers (T2, T3, T4, T5 and T6) were applied to two hybrid varieties (PITA 3 and FHIA 21) and a traditional variety (CORNE 1) on an experimental split plot plan with a planting density of 2500 plants per hectare. Results showed that fertilizers improve parameters of plantain than control (T1). T6 with high potassium content (240 kg·ha−1 N and 987 kg·ha−1 K) improved the growth (35.72 ± 0.95 cm·month−1) and the widening (9.56 ± 0.17 cm·month−1) of PITA 3, and performed FHIA 21 agronomic parameters by reducing the length of the production cycle and increased the length of fruits. T2 treatment improved FHIA 21 agronomic and yield parameters. Also, the weight of CORNE 1 regimens (9.00 ± 0.67 kg) and fruits (296.59 ± 4.50 g), the length (33.37 ± 0.31 cm) and the circumference (14.73 ± 0.31 cm) increased with T2. T4 induced shorter production cycle of PITA 3 (390.40 ± 0.67 cm·month−1), improved PITA3 regimens weight (10.33 ± 0.44 kg) and the number of hands by regimen (6.00 ± 0.00) of FHIA 21. T3 with weak nitrogen content (120 kg·ha−1 N and 658 kg·ha−1 K) improved the characteristics of PITA 3 fruits notably, the weight (176.09 ± 2.96 g) and the circumference (13.87 ± 0.89 cm). T5 (240 kg·ha−1 N and 329 kg·ha−1 K) performed CORNE 1 trees number of sheets (3.85 ± 0.16). CORNE 1 cycle production with T6 treatment was 137.80 days longer than those of T2 treatment (483 ± 3.50 days). In conclusion, with T2 and T6, growth parameters were globally improved in FHIA 21 by the regimen largest and the higher number of fingers, and productivity parameters were improved in CORNE 1 by the heaviest, the longest and the thickest of the fruits.

Effects of Long-term K Fertilizer Application on the Crop Yield and K Distribution of Soil Aggregates in a Paddy-Upland Rotation System

[Objective]A long-term paddy-upland experiment was conducted to evaluate the effects of the recommended amount of potassium( K)fertilizer on crop yield,distribution of soil aggregate,and soil available K content. It was mainly to ascertain the distribution of K in the soil aggregate components in the paddy-upland rotation system,and then to provide theoretical basis for soil structure improvement,K pool management,and reasonable application of K fertilizer. [Method]There were 2 treatments selected,namely,NP(-K) treatment and NPK( + K) treatment in this study. Then the effects of K fertilizer application on the yield,available K content,and aggregate distribution in the middle rice-winter rape rotation system were analyzed. [Result]The results showed that the output of the crop rotation was affected by the year and fertilization. Compared with NP(-K),the average yield increases of rice and winter rape after application of K fertilizer were 0.51 and 0.33 t/hm2,with the increments of 7.5%and 14. 1% respectively. The long-term application of K fertilizer( 7 a) had no significant effects on the distribution of soil aggregates but could significantly increase the water-soluble K content and available K content at depths of 20-30 and 30-40 cm,and available K content of aggregates in each particle size. In addition,the balance of available K at the 10-20 and 30-40 cm of soil layers was the most significant through calculation of surplus-deficit value of available K in agglomerates of different soil layers. [Conclusion]Compared with the initial available K content in the farmland in 2011,the current K fertilizer application could lead to that farmland K content continues to decline. Therefore,we should pay attention to straw returned and supplement of organic K fertilizer,to maintain crop rotation system's productivity and soil K balance.

Optimizing Yield and Quality of Canola Cultivars Using Various Potash Levels

The response of several canola cultivars to different potassium (K) levels was investigated in terms of various agronomic parameters including yields, oil and protein contents in a trial conducted at The University of Agriculture, Peshawar-Pakistan in Rabi 2010-11. Three cultivars including Bulbul-98, Abaseen-95 and Dure-NIFA, with five levels of potassium i.e. 0, 30, 60, 90 and 120 kg&middotha-1 were used in Randomized Complete Block (RCB) design with four replications and factorial arrangement. A larger number of days to 50% flowering (116.6 days), plant height (203.8 cm), leaf area index (4.4), 1000 grain weight (3.5 g), biological yield (13189.3 kg&middotha-1), grain yield (1799.2 kg&middotha-1) and harvest index (13.9%) were obtained in K applied plots than the plots where K was not applied. The highest oil (45.1%) and protein (27.7%) was obtained in plots where K was applied at the rate of 120 and 90 kg&middotha-1, respectively. Among cultivars, Bulbul-98 and Abaseen-95 had higher seed yield and oil percentage. Bulbul-98 had more protein content than Abaseen-95 and Durre-NIFA. On average, cultivars gave higher and at par grain yield at 60, 90 and 120 kg&middotha-1. However, they produced higher and at par oil and protein percentage at 90 and 120 kg&middotha-1. Bul-bul-98 and Abaseen-95 are recommended for higher grain yield and oil content for general culti-vation in Peshawar valley. However, for higher protein content, Bulbul-98 is better. Potassium applied at 60 kg&middotha-1 is recommended for higher grain yield, however, for higher oil and protein content, K at 90 kg&middotha-1 is recommended.

稻草和紫云英协同还田下钾肥施用量对水稻产量及土壤供钾能力的影响

[目的]水稻生产对钾素的需求量大,研究稻草和紫云英协同还田条件下不同施肥处理对水稻产量和土壤钾素形态变化的影响,旨在保障我国南方水稻的高产和土壤钾素高效利用。[方法]不同轮作模式钾肥定位试验位于中国农业科学院红壤实验站内(始于2016年)。试验处理包括不施肥和冬闲(CK)、氮磷钾肥和冬闲(F)、氮磷钾肥和冬种紫云英(CM)、氮磷钾肥配合稻草还田和冬种紫云英(RCM)、氮磷减钾50%配合稻草还田和冬种紫云英(50%KRCM)。在试验第3年(2019年)于水稻收获后调查分析水稻产量和钾素含量,以及耕层土壤中速效钾和缓效钾含量,计算水稻钾素吸收量、钾素生理效率和钾素表观平衡,并进一步探讨水稻产量和钾素各指标之间的相关性。[结果]与CK处理相比,紫云英轮作显著提高水稻年产量,增幅以RCM、50%KRCM较高,分别为59.4%和59.7%。两者协同还田和紫云英单独还田均可显著提高有效穗数,相比化肥冬闲处理(F),增幅为53.1%~63.3%,在稻草和紫云英协同还田下,减钾对水稻产量构成因素的影响不明显。和F处理相比,RCM、50%KRCM处理显著提高了土壤速效钾和缓效钾含量,增幅分别为87.6%、41.1%和14.0%、12.1%,紫云英单独还田(CM)可显著提高土壤速效钾含量,对缓效钾含量的影响不显著。与RCM处理相比,50%KRCM处理的土壤速效钾含量显著降低了24.8%,缓效钾含量没有显著变化。和CK处理相比,RCM处理显著提高了稻谷含钾量,增幅为6.7%,4个施肥处理均显著提高了稻草和稻谷吸钾量,钾素表观平衡均表现为盈余,RCM和50%KRCM处理的钾素盈余量高于CM处理,但50%KRCM处理的钾素盈余量比RCM处理降低了119.7 kg/(hm^(2)·a)。钾素盈余量与土壤速效钾含量变化呈显著正相关,钾素盈余量每增加1 kg/(hm^(2)·a),土壤速效钾含量提高0.25 mg/kg。施肥降低了钾素生理效率,CM、RCM和F处理的钾素生理效率比CK降低了10.3%~15.5%。土壤速效钾含量、植株总吸钾量、钾素表观平衡和水稻产量之间均显著正相关,植株总吸钾量每增加1 kg/hm^(2),水稻产量提高30.5 kg/hm^(2),钾素表观平衡每增加1 kg/(hm^(2)·a),水稻产量提高9.5 kg/hm^(2)。[结论]稻草和紫云英协同还田可增加水稻有效穗数进而提高稻谷产量,增加钾素盈余量可提高土壤速效钾和缓效钾含量,两者协同还田提升水稻产量和土壤供钾能力的作用优于紫云英单独还田。稻草和紫云英协同还田条件下减少钾肥施用量,显著降低钾素盈余量,但没有降低土壤钾素的供应能力,因此,可适当减少钾肥的施用量。

密度及氮磷钾肥用量对绿豆产量质量的影响

研究不同种植密度及氮、磷、钾肥用量对绿豆产量单一指标及产量质量综合评价指标的影响,为绿豆高产优质生产提供理论依据和技术支撑。以密度及氮、磷、钾肥用量为试验因素,采用四元二次正交旋转组合设计,开展田间试验,测定干籽粒重、纯粮率、蛋白质、脂肪、淀粉5项产量质量指标,采用基于博弈论的组合赋权法综合层次分析法和熵权法权重,确定各单一指标权重,并运用逼近理想解的排序方法构建绿豆产量质量综合评价指标。建立密度及氮、磷、钾肥用量与产量单一指标及产量质量综合评价指标的二次回归数学模型,开展主因素、单因素、交互效应及优化方案分析。干籽粒重、纯粮率、蛋白质、脂肪、淀粉权重分别为0.4070、0.2112、0.1246、0.0949、0.1623。当其他因素为中间水平时,绿豆产量单一指标及产量质量综合评价指标分别随密度、施氮量、施磷量、施钾量增加呈开口向下的抛物线型变化。各因素对绿豆产量单一指标、产量质量综合评价指标的主效应表现为密度>施钾量>施磷量>施氮量。密度、施氮量、施磷量、施钾量之间存在正交互作用。密度为173004~194590株/hm^(2),氮、磷、钾肥用量分别为N 67.33~77.84 kg/hm^(2)、P2O5107.26~116.75 kg/hm^(2)、K_(2)O86.90~90.81 kg/hm^(2),绿豆产量、产量质量综合均较优。

不同配方基肥对温郁金产量及其营养元素含量的影响

本试验研究了基肥氮磷钾不同比例配施对温郁金产量与品质的影响,为提高温郁金产量及品质提供科学依据。本研究采用大田试验,设置4个不同的施肥配方,各处理基肥用量均为750 kg·hm^(-2)。结果表明,在氮磷钾总用量相等的前提下,基施配方肥2的温郁金产量最高,与常规施肥比较,温郁金地下部分根茎、块根分别增产11.3%、17.9%。配方肥1和3相较常规施肥也提高了温郁金的产量,但统计上无显著差异。与常规施肥相比,配方肥处理提高了温郁金中氮和磷含量。同时,基施配方肥还可以提高根茎、块根中Ca、Mg及微量元素Zn、B等含量。综上,基肥施用配方肥2既能提高温郁金产量,又能提高根茎、块根中的大量元素及中微量元素含量,具有较好的推广应用价值。

“妃子笑”荔枝高产若干生长发育性状

“妃子笑”荔枝是我国栽培区域最广的荔枝品种,比较研究不同区域“妃子笑”生长发育特性可为树冠、养分管理和成花着果调控及区域适应性发展等参考,为荔枝品种制订高产和克服“大小年”技术方案提供借鉴。2008—2022年,调查统计华南六省(区)北纬18°32′~28°47′的24县(区)39个示范园“妃子笑”物候期;于始花期调查海南、广东、广西和云南省(区)18个果园“妃子笑”结果树枝条、叶片和花穗生长量,并取样分析枝条、叶片、花穗主要养分含量,计算植株不同部位营养需求量。结果表明,主产区“妃子笑”末次秋梢成熟期8月下旬至11月中旬,现“白点”(花穗原基)期11月下旬至翌年2月中旬,盛花期2月上旬至4月上旬,果实成熟期4月下旬至7月底。3次秋梢生长分别约为35.9、39.5和40.2 d,秋梢老熟至现花穗原基(花诱导)约87 d,花穗与花芽分化期约56 d,果实发育期约需63 d。海南等地区“妃子笑”采果后树冠重回缩修剪至1.5 m高,形成矮化树形,而粤西等地修剪至2~3 m高,塑造高大树形。“妃子笑”结果植株采果后秋梢生长1~3次,树冠表面积的平均枝梢数16条/m2,秋梢平均长度37.7 cm,秋梢复叶数17片、叶片数104片。“妃子笑”单株不同部位年生长量,以鲜质量计分别为秋梢枝条16.8 kg,叶片40.2 kg,花穗17.2 kg;以干质量计为秋梢枝条9.50 kg,叶片23.24kg,花穗7.19kg。主要养分含量为秋梢枝条中氮0.76%、磷0.26%、钾0.72%、钙0.54%、镁0.15%;叶片中氮1.79%、磷0.17%、钾0.94%、钙0.77%、镁0.25%;花穗中氮2.20%、磷0.30%、钾1.74%、钙0.32%、镁0.29%。单株50 kg的产量,年度枝叶、花穗和果实生长所需主要元素为氮0.70 kg、磷0.10 kg、钾0.46 kg,秋梢期氮、磷、钾用量分别占比全年用量的71.4%、70.0%、63.0%。从多年产量稳定性看,海南省陵水县、琼海市、海口市,广西北海铁山港区、合浦县,广东省廉江市等地是“妃子笑”适应性表现较好的栽培区。综合而言,随着纬度北移和海拔升高,“妃子笑”物候期延后,果实成熟期持续3个月以上;各地区“妃子笑”物候期相差较大的是末次秋梢成熟期和果实成熟期,差异较小的是花芽诱导期;枝叶养分需求较大,确保秋梢生长量是支撑产量和品质的重要基础。

供钾水平对宁南山区花椰菜产量及钾素平衡的影响

【目的】为宁夏冷凉花椰菜生产中钾肥合理施用提供科学依据。【方法】以宁夏冷凉主导花椰菜为试验材料,设置0(K_(0))、10(K_(10))、20(K_(20))、30(K_(30))、40 kg/667m^(2)(K_(40))5个施钾水平,通过田间试验,研究供钾对露地花椰菜产量、钾素吸收分配利用及土壤根层钾素质量与平衡的影响。【结果】供钾显著增加花椰菜产量,增产率在5.32%~16.24%,供钾水平与花球产量呈极显著的二次抛物曲线关系,最高产量为3 529.43 kg/667 m^(2),最佳供钾水平为24.28 kg/667 m^(2)。在苗期和莲座期茎叶是花椰菜钾元素的累积中心,不同处理茎叶分配比例在49.67%~90.49%,进入成熟期花球是花椰菜钾元素的累积中心,不同处理花球累积分配比例在42.25%~53.73%,整株花椰菜钾素累积量苗期以K_(30)处理最高,莲座期和成熟期均以K_(20)处理最高,较对照分别显著提高69.40%、79.38%。钾肥利用效率为21.77%~40.31%,以K20处理的钾肥利用率、贡献率及农学效率均最高,分别为45.28%,21.31%、38.670 kg/kg。供钾水平低于20 kg/667 m^(2)时,土壤钾素平衡表现为亏缺,供钾水平超过30 kg/667 m^(2)钾素盈余由负转正,再继续投入钾肥,钾素盈余。【结论】综合考虑花椰菜钾素吸收利用分配与产量和土壤钾素有效性与菜田钾素收支平衡等因素,建议宁夏南部山区花椰菜适宜的供钾水平为21.82~29.24 kg/667 m^(2)。

钾肥和氮肥配施对北疆棉花干物质积累分配及产量的影响

为探究不同钾肥用量对氮肥减量下棉花干物质积累分配及产量的影响,采用裂区试验设计,设置施钾量为主区,分别为0、120.0、240.0 kg/hm^(2)3个水平;施氮量为副区,分别为地方常规施氮(375.0 kg/hm^(2))、10%减量施氮(337.5 kg/hm^(2))、20%减量施氮(300.0 kg/hm^(2))、30%减量施氮(262.5 kg/hm^(2))和不施氮(0 kg/hm^(2))5个水平,共15个处理。于2023年在沙湾市大泉乡进行田间试验,研究分析了减氮增钾对棉花产量、净光合速率、SPAD、干物质积累及分配的影响。结果表明,施钾240.0 kg/hm^(2)、施氮337.5 kg/hm^(2)处理棉花产量达7704.51 kg/hm^(2),较常规施氮不施钾处理显著提高28.05%,减氮10%~20%、配施240.0 kg/hm^(2)钾肥较不施钾肥常规施氮处理显著提高了棉花的净光合速率、单株干物质积累量,营养器官干物质积累量、生殖器官干物质积累量,提高了单铃重和单株铃数。增施240.0 kg/hm^(2)钾肥和减施10%氮肥(337.5 kg/hm^(2))可实现减氮增产的效果。

氮磷钾配方施肥提高林下七叶一枝花产量和重楼皂苷含量

【目的】研究氮、磷、钾不同组合用量对林下栽培七叶一枝花产量及重楼皂苷含量的影响,为七叶一枝花人工栽培合理施肥提供参考。【方法】采用“3414”试验设计,利用福建南平杉竹混交林下4年生七叶一枝花(Paris polyphylla Smith var.chinensis (Franch.) Hara)进行田间试验,将氮、磷、钾肥当地适宜水平定为“2”,分别为N 270 kg/hm^(2)、P_(2)O_(5) 375 kg/hm^(2)、K_(2)O 300 kg/hm^(2),不足“1”和过量“3”水平分别为适宜水平的0.5、1.5倍。在七叶一枝花收获时期,测定其植株形态、根茎产量、4种重楼皂苷含量等指标,并计算生产效益。【结果】氮、磷、钾肥用量均显著影响七叶一枝花的植株形态、根茎产量和重楼皂苷含量,对七叶一枝花根茎产量的提升率分别为59.75%、27.54%、63.15%,以钾肥的贡献率最高,其次为氮肥,磷肥较低。N1水平下,增加磷、钾水平显著降低七叶一枝花的株高、茎粗和叶长,N3水平七叶一枝花的株高、叶长均达到最高,但茎粗低于N1和N2水平,表明适宜氮肥用量对七叶一枝花的生长至关重要。七叶一枝花的根茎产量和总重楼皂苷含量还受肥料交互效应的影响。当N、P_(2)O_(5)、K_(2)O用量分别为270、375、450 kg/hm^(2) (N_(2)P_(2)K_3)和270、375、300 kg/hm^(2)(N_(2)P_(2)K_(2))时,根茎产量达到最高,分别为2804、2648 kg/hm^(2)。N_(2)P_(2)K_3的总重楼皂苷含量也最大,达到1.62%,显著高于其他处理。施氮磷钾肥净增收效益在N_(2)P_(2)K_3处理下最高,N_(2)P_(2)K_(2)处理次之。【结论】适量的氮、磷肥配合较高的钾肥可显著提升七叶一枝花根茎产量和总重楼皂苷含量,提高七叶一枝花的经济效益。因此,在供试地区,推荐N、P_(2)O_(5)、K_(2)O用量分别为270、375、450 kg/hm^(2)。

氮肥和钾肥减施对沙地马铃薯生长及产量的影响

利用田间试验探讨氮肥和钾肥减施对马铃薯生长和产量的影响,为榆林北部风沙区马铃薯绿色高效栽培的科学施肥提供理论基础。本试验设置N_(95)K_(100)(N95%、K100%)、N_(90)K_(100)(N90%、K100%)、N_(100)K_(95)(N100%、K95%)、N_(100)K_(90)(N100%、K90%)、N_(100)K_(100)(N100%、K100%)五个处理。结果表明:在马铃薯整个生育期,N_(100)K_(100)处理的株高、叶片SPAD值、叶片净光合速率(Pn)、胞间CO_(2)浓度(Ci)和气孔导度(Gs)均为最高。在苗期-块茎形成期,两种减氮处理(N_(95)K_(100)和N_(90)K_(100))的株高、叶片SPAD值、叶片Pn值和Ci值低于两种减钾处理(N_(100)K_(90)和N_(100)K_(90));在块茎膨大期-成熟期,两种减氮处理的茎粗、叶片SPAD值、叶片Pn值、Ci值和Gs值均高于两种减钾处理,且N_(90)K_(100)处理的上述指标显著高于两种减钾处理(P<0.05)。N_(90)K_(100)处理的马铃薯产量略低于N_(100)K_(100)处理,但显著高于其他处理8.01%~18.53%(P<0.05),且N_(90)K_(100)处理的马铃薯的商品薯率显著高于其他处理5.99%~17.58%(P<0.05)。因此,N_(90)K_(100)处理可减少氮肥投入,有助于马铃薯产量稳定和商品薯率提高。

施钾对夏花生产量、品质及光温生理特性的影响

【目的】探究不同施钾水平对夏花生产量、品质及生育期钾素积累动态、光温生理特性和根系形态的影响,为花生合理施钾提供科学依据。【方法】2021—2022年在河南省温县进行钾肥用量田间试验,供试品种为豫花22,设施钾量0(K0)、45 kg·hm^(-2)(K45)、90 kg·hm^(-2)(K90)、135 kg·hm^(-2)(K135)和180 kg·hm^(-2)(K180)5个处理,于成熟期测定夏花生荚果产量和品质,并分别于苗期、花针期、结荚期、饱果期测定叶片SPAD值、冠层光合有效辐射和冠层温度,分析植株钾积累量和根系形态。【结果】随施钾量增加,两年度花生荚果产量可分别用“线性+平台”和“一元二次方程”拟合,适宜施钾量分别为164和135 kg·hm^(-2),施钾处理平均增产17%。成熟期籽粒粗蛋白、含油量和氨基酸含量均随施钾量增加呈先升高后趋于稳定趋势。与不施钾相比,施钾处理籽粒粗蛋白、含油量和氨基酸含量两年度平均增幅分别为7.85%、3.98%和13.97%,效果显著。运用Logistic方程对夏花生钾素积累量进行非线性回归拟合,得出施钾主要提高了花生钾素最大积累速率(Vmax)和平均积累速率(Vmean),推迟吸收峰值的出现(Tmax),延长快速积累期(Δt)与活跃积累期(Taas),促进夏花生持续快速生长发育。此外,各生育时期冠层最高温、最低温与平均温度均随施钾量的增加显著降低;施钾135 kg·hm^(-2)可显著增加花生叶片SPAD值与冠层光合有效辐射量(APAR)和分量(FPAR),并对根系形态具有积极影响。【结论】合理施钾可显著提高夏花生产量、改善品质、促进钾素积累利用并显著改善生育期光温生理性能。本试验条件下夏花生推荐施钾量为135—160 kg·hm^(-2)。