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不同施肥配比对宁夏盐碱土壤油用向日葵产量的影响 总被引:1,自引:0,他引:1
研究了不同施肥配比对宁夏盐碱土壤向日葵产量的影响,建立了一元二次肥料效应函数方程.结果表明:对碱化土壤施氮量达到10.56 kg/667m2时,产量达到最大值183.2 kg/667m2;当施磷量达到5.71 kg/667m2时,产量达到最大值156.9 kg/667m2;最高产量施肥配方氮磷钾配比为10.56∶5.7... 相似文献
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Y. A. Nanja Reddy M. N. Keshava Murthy K. Virupakshappa R. Uma Shaanker 《Journal of Agronomy and Crop Science》1995,175(2):83-86
Measurement of total leaf area per plant in crop improvement programmes for a variety of purposes is often very tedious and time consuming. In this paper, we offer a rapid and non-destructive method of estimating the total leaf area in sunflower at the time of anthesis. We show that multiplying the leaf area of a specific leaf position from the apex by the total number of leaves per plant yields total leaf area with more than 95 % accuracy. The specific leaf position for any given genotype in sunflower can be arrived at by multiplying the total number of leaves per plant by the factor 0.355 and rounding off to the nearest highest integer. This technique can be used for the rapid estimation of leaf area per plant at anthesis for any given genotype of sunflower. 相似文献
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Forty-five accessions of sunflower collected from different countries were screened for salinity tolerance after 2 weeks growth in sand culture salinized with 150 meq l?1 of NaCl2+ CaCl2 (1:1 ratio equivalent wt. basis) in half strength Hoagland's nutrient solution. The results for plant biomass of 45 accessions show that there was considerable variation in salinity tolerance. In a further greenhouse experiment, the salinity tolerance of three tolerant (HO-1, Predovik, Euroflor) and two sensitive (SMH-24, 9UO-985) lines (selected on the basis of their performance in the seedling experiment) was assessed at the adult stage to evaluate the consistency of salinity tolerance at different growth stages. All three salt tolerant accessions produced significantly greater plant biomass, seed yield and seed oil content than the salt sensitive accessions. The tolerant accessions accumulated less Cl? and more K+ in the leaves under saline conditions compared with the salt sensitive accessions. The salt tolerant accessions also maintained relatively high leaf K:Na ratio and K+ versus Na+ selectivity. Although statistically nonsignificant, all three tolerant accessions had greater soluble carbohydrates, soluble proteins, total free amino acids and proline in the leaves than the sensitive accessions. A field trial conducted in a salt-affected field confirmed the greenhouse results of the selected accessions. This study shows that salinity tolerance of sunflower does not vary with stage of plant cycle, so selection for increased salt tolerance can be carried out at the initial growth stage. Secondly, it is found that there is great variation of salt tolerance in sunflower. Low uptake of Cl?, high uptake of K+, and maintenance of high K:Na ratios and K+ versus Na+ selectivity in the leaves and possibly the accumulation of organic osmotica such as soluble carbohydrates, soluble proteins, proline and free amino acids seem to be the important components of salt tolerance in sunflower. 相似文献
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本试验通过对接种黄萎病的地块进行不同浇水次数的处理来调查分析浇水次数对向日葵黄萎病发生程度及产量的影响.结果表明随着浇水次数的增多,向日葵黄萎病的发病严重度也随之增加,且向日葵的产量呈现降低的趋势.在接种的地块中浇水1次的病情病指由29.0递增到浇水3次51.5;产量则由浇水1次的4690.95kg/公顷降低至浇水3次的3815.55kg/公顷. 相似文献