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61.
AbstractCrop yield response to micronutrient fertilization is difficult to predict, particularly under unfavorable environmental conditions as these may alter both crop nutrient demand and the soil micronutrient supply to plant roots. The research objective was to evaluate the effect of various soil temperature and moisture conditions on crop growth response to added micronutrient copper (Cu), zinc (Zn), and boron (B) along with soil micronutrient supply and distribution among fractions. Brown and Dark Brown farm soils collected from southern Saskatchewan were used to grown wheat, pea and canola within controlled environment chambers. The biomass yields of all crops decreased under cold soil temperature and moisture stress (drought and saturated) conditions. Greater plant uptake of Cu, Zn, and B was associated with optimum (i.e., field capacity) soil moisture and warm temperature (23°C) growing conditions, compared to drought (i.e., 50% field capacity), saturated, and cold (5°C) temperature conditions. Environmental stress had the greatest impact on pea growth, reducing crop yield and micronutrient utilization efficiency more than 95%. Soil supplies of Cu and Zn were most negatively impacted by drought stress due to reduced mobility of these diffusion limited nutrients. The extractable micronutrients levels and chemical speciation fractions of Cu, Zn, and B indicating that bioavailability and micronutrient transformation were not affected during our short-term (i.e., six-weeks) study. However, it is suggested that assessments of micronutrient forms also be conducted on soil samples under actual moisture and temperature conditions as they exist in the experiment, as well as on dried, processed samples. 相似文献
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本文采用土壤农化分析手段和田间生物试验方法,评价黑龙港流域古河道细质沙土施用微量元素的有效性。结果表明:该地区土壤肥力低,严重缺乏氮、磷等大量元素;土壤有效微量元素锌、铁和硼含量均低于临界浓度;花生施用锌、铁、硼和钼肥分别增产13.9%。12.0%,8.0%和3.0%,小麦喷施锌、锰肥分别增产16.2%和4.8%。 相似文献
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滨海沙土微量元素与木麻黄生长的关系 总被引:9,自引:0,他引:9
本文探讨了广东滨海沙土中微量元素B、Mo、Mn、Cu、Zn与木麻黄生长的关系,结果表明:B、Mo有利于促进生长与抗病,Cu含量高对生长有抑制作用,其余的作用不明显。 相似文献
66.
Thomas J. Rego Kanwar L. Sahrawat Suhas P. Wani Gazula Pardhasaradhi 《Journal of plant nutrition》2013,36(10):1569-1583
On-farm studies were conducted during 2002–2004 to determine fertility status, including sulfur (S) and micronutrients, and crop response to fertilization on farmers' fields in the semi-arid zone of India. Nine hundred-twenty four soil samples taken from farmers' fields, spread in the three districts of Andhra Pradesh (India), were analyzed for soil chemical fertility parameters. Results showed that samples were low in organic carbon (C), total nitrogen (N), and low to moderate in extractable phosphorus (P), but adequate in available potassium (K). Analyses of soil samples for extractable S and micronutrients was most revealing and showed that 73–95% of the farmers' fields were deficient in S, 70–100% in boron (B), and 62–94% in zinc (Zn). On-farm trials conducted during three seasons (2002–2004) showed significant yield responses of maize, castor, groundnut, and mung bean to the applications of S, B, and Zn. The yield responses were larger when S, Zn, and B were applied along with N and P. Applications of S, B and Zn also significantly increased the uptake of N, P, K, S, B, and Zn in the crop biomass. Results show widespread deficiencies of S, B, and Zn under dryland agricultural conditions; results also show that the nutrient deficiencies can be diagnosed by soil testing. It was concluded that the drylands in the semi-arid regions of India were not only thirsty (water shortage), but also hungry (nutrient deficiencies). 相似文献
67.
Karen I. Davis Carl E. Niedziela Jr. Muchha R. Reddy Brian E. Whipker Jonathan M. Frantz 《Journal of plant nutrition》2013,36(7):1079-1086
Clerodendrum thomsoniae plants were grown in silica sand culture to induce and photograph nutritional disorder symptoms. Plants were grown with a complete modified Hoagland's all nitrate solution. The nutrient deficiency treatments were induced with a complete nutrient formula minus one of the nutrients. Boron toxicity was also induced by increasing the element ten times higher than the complete nutrient formula. Reagent grade chemicals and deionized water of 18-mega ohms purity were used to formulate treatment solutions. The plants were automatically irrigated and the solution drained from the bottom of the pot and captured for reuse. The nutrient solutions were completely replaced weekly. Plants were monitored daily to document and photograph sequential series of symptoms as they developed. Typical symptomology of nutrient disorders and critical tissue concentrations are presented. Plants were harvested for nutrient analysis when initial symptoms were expressed. Nutrient deficiency symptoms were described and foliar nutrient concentrations provided. 相似文献
68.
ABSTRACTA greenhouse experiment was carried out to evaluate the effect of 0, 25, 50 and 100 ton ha?1 of cattle manure-derived biochar (BC) and soil moisture conditions (SMC) of 100%, 70% and 55% of water-holding capacity (WHC) on soybean production. Most of the macro and micronutrient, soil chemical characteristics and yield production of soybean were significantly affected by BC. Under drought, BC was more effective than that of the non-stressed conditions. Interaction effect of SMC and BC on soil iron (Fe), zinc (Zn), manganese (Mn), calcium (Ca), magnesium (Mg), phosphorus (P) and nitrogen (N) concentrations was also significant indicating that different levels of water supply might show different impact under different levels of BC. Under drought, the higher BC applied, the higher grain yield obtained. Application of 0 to 75 ton BC ha?1 under WHC caused a high grain yield but 100 ton BC ha?1 significantly decreased it as compared with the other levels of BC. Positive impacts of BC may be more pronounced under drought. High level of BC in non-stressed conditions may reduce grain yield as occurred in this study. The statistical techniques indicated that higher content of macro and micronutrients negatively associated with yield production of soybean. 相似文献
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中国甜菜种植主要分布在东北、西北、华北三大生态区,为探明当前甜菜生产上块根产量和含糖量的主要养分限制因子,分别在三大甜菜产区,通过设置缺素处理,进行了2年23个点的田间小区试验。结果表明:在东北区氮磷对产量限制显著(P<0.05),硼对产量和钾对含糖的限制作用在所有试验区域均有不同程度表现,甜菜产质量主要限制因子的顺序依次为N>P>K>B>Zn。在西北区氮和硼是产量的最主要限制因子,缺乏后减产效果均达到显著水平(P<0.05),各元素对产质量的限制依次为N>B>P>K>Zn。华北区5种元素对甜菜产量的限制作用均达到显著水平(P<0.05),其中氮的作用最大,其他4种元素的作用接近,锌对含糖的限制作用达到显著水平(P<0.05),各因子对甜菜产质量的限制依次为N>Zn>B>P>K。 相似文献