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41.
播期对油菜"两优586"生育、产量及抗性的影响 总被引:1,自引:1,他引:0
研究了播期对油菜"两优586"生育、产量及抗性的影响。结果表明:在江西宜春,"两优586"的最佳播期为10月8日,适宜播期为10月1日~10月15日,产量可达1792.50~1929.75kg/hm2,生育期适中(190d左右),单株有效角果数较多,为345个左右,且抗性较强,发病率低于15%,倒伏率低于10%。 相似文献
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Two experiments were undertaken in southern Greece during 2000–2002 in which turnip-rooted parsley was tested for its suitability for cultivation in comparison with locally grown curly-leafed and plain-leafed forms. Plants were harvested when the foliage was acceptable for marketing, rather than on completion of the vegetative cycle, hence root size was relatively small. In year 1, the foliage development of plain-leafed parsley was significantly higher than that of the other two forms, irrespective of sowing date. In year 2, both plain-leafed and curly-leafed parsley produced more foliage than turnip-rooted parsley in the early sowing (November), but not in subsequent sowings (December and February). During both years, root development was higher in turnip-rooted parsley than in curly-leafed parsley, although in the November and February sowings of year 1 the root weight of both plain-leafed and turnip-rooted forms were similar. In all three types of parsley, foliage yield fell off significantly in the spring sowing (February), and in year 1 there was a considerable decrease in root production as well. In most cultivars, foliage weight was higher when plants were grown from transplanted seedlings rather than by direct sowing, whereas the effect of sowing method on root weight was sowing date dependent. Cultivar differences in the foliage weight of direct sown and transplanted plants were reflected by differences in plant height and, in some cases, by leaf number. It is concluded that although overall turnip-rooted parsley produced rather less foliage than that plain-leafed parsley, this was compensated for by the satisfactory production of roots and therefore turnip-rooted cultivars may constitute a suitable crop for introduction to the Mediterranean region. 相似文献
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Weed and nutrient management in cropping systems of semi-arid areas is a major constraint to cereal yield. Where the use of herbicides is banned or discouraged, the competitive ability of a crop is crucial to reduce weed growth and diffusion. Genotypic differences in the competitive abilities of crops are an important trait to reduce weeds, especially for plant height. However, there is contrasting information about the interactions of other management practices and genotypic traits on wheat yield and competitive ability against weeds and weed growth. The present study investigated yield and quality of durum wheat (Triticum durum Desf.) and weed growth and composition for two wheat cultivars with contrasting competitive abilities against weeds. Wheat was grown under three spatial arrangements (5-cm, 15-cm, 25-cm inter-row distance) and three sowing densities, and broadleaf weeds were either removed or not. The sowing rate did not affect the yield of these wheat cultivars or the weed growth. Reduced inter-row distance dramatically reduced weed biomass for both wheat cultivars, and increased wheat yield and nitrogen uptake in the low-competitive, high-yielding, semi-dwarf cv. ‘PR22D89’, when both weed free and with weeds. These results have direct implications for weed and nutrient management in low-input and organic cropping systems. 相似文献
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南方春大豆不同播季主要农艺性状的变化及其遗传研究 总被引:4,自引:0,他引:4
本文以12个南方春大豆早熟品种(系)和12个中熟品种(系)为材料,进行春,秋播试验,研究主要农艺性状的秋播变异率,遗传变异系数,遗传力和遗传进度,结果表明:1,两熟期组秋播变异率平均,除分枝起点为负值以外,其它11个性状在2.36%-52.88%之间,说明秋播对为结性状均有一定影响;熟期组之间各性状秋播变异率的大小亦存在较大差异,如秋播对早熟组株高,主茎节数,结荚节数,结荚高度,主茎荚数和百粒重的 相似文献
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播期对大豆开花及产量的影响 总被引:11,自引:3,他引:8
通过对不同播期条件下大豆开花结英规律的调查,建立了大豆开花模式,结果表明,在大豆开放小花数量累积的概率与开花日序呈对数函数关系。回归模型为:YP=A+B.Lnx;确定了不同播种时期处理的,“有效花期”范围;分析表明“有效花期”较长,落花落英率较小,产量罗高。“有效花期”长短与结英率及产量具有一定的相关关系,不同处理的产量差异达极显著水平。 相似文献
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不同播期对威芋5号产量及生长发育的影响 总被引:1,自引:0,他引:1
以马铃薯威芋5号为试验材料,研究在威宁县不同播期对威芋5号生理指标和产量的影响。试验结果表明,3月23日播种,威芋5号产量最高,可达2 116.46 kg/667 m2,纯收入为1 134.81元/667 m2,经济效益显著,而不同播期对威芋5号生育期影响不大。 相似文献
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[目的]研究施肥对核桃楸床播育苗的影响,达到培育优质壮苗的目的。[方法]研究不同施肥种类及施肥量对核桃楸苗木的茎干、根系生长等特性的影响。[结果]当施尿素15 g/m2+磷酸二氢钾15 g/m2时,苗木在苗高、地径、主根长、侧根数等指标均高于不施肥和其他施肥处理,有利于优质壮苗的培育。[结论]在生长季以施尿素15 g/m2+磷酸二氢钾15 g/m2或磷钾复合肥时,苗木的整体质量最优。 相似文献