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21.
[目的]研究不同播期对小麦籽粒灌浆特征及参数的影响。[方法]以小麦品种9356为供试品种,设置3个播期,分析播期与小麦籽粒灌浆的关系。[结果]结果表明:不同播期下小麦籽粒灌浆过程可以用Richards方程描述;播期对籽粒灌浆参数均有一定影响,但不同参数影响也不同;平均灌浆速率与小麦粒重呈极显著正相关关系。[结论]播期对籽粒灌浆持续时间和籽粒灌浆平均速率均有一定的影响,并且对平均灌浆速率的影响较为显著. 相似文献
22.
[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
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播种密度对小麦茎秆大维管束系统和穗部发育的影响 总被引:4,自引:1,他引:4
研究了不同播种密度与小麦地上部伸长节间大维管束系统和穗部生产力之间的关系。结果表明:不同播种密度显著影响地上部伸长节间大维管束发达程度(大维管束数目和横截面积)和穗部生产力,其发达程度与穗部生产力呈显著正相关。播种密度的差异显著影响地上伸长节间茎壁厚度、节间长度和粗度及茎高,从而影响到小麦的抗倒能力。同时,不同播种密度也显著影响单位面积穗数、单穗结实粒数、单穗重及经济产量。 相似文献
25.
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
28.
肥密水平对不同基因型冬小麦籽粒灌浆特性的影响 总被引:2,自引:0,他引:2
为确定施肥量和种植密度对不同品种小麦灌浆特性的影响, 采用多因素随机区组设计试验方法, 对优质冬小麦"陇鉴301"、"宁麦5号"和"1R17"的籽粒灌浆特性进行了研究, 应用Logistic方程对灌浆进程进行了拟合, 并就施肥量、种植密度和品种3因素进行了方差分析.结果表明:不同肥密水平下小麦灌浆进程符合Logistic生长曲线, 呈"慢-快-慢""S"型变化.肥密水平对3品种12项灌浆参数均产生影响, 但影响的具体参数和影响程度因品种而异.在高密度高肥处理下, "陇鉴301"、"宁麦5号"较为适应, 产量最高(4 188.09 kg·hm-2, 3 789.89 kg·hm-2);高密度中肥处理下, "1R17"最为适应, 产量最高(3 018.18 kg·hm-2), 且灌浆过程达到最佳状态.不同品种肥密互作效应达极显著水平, 具有正向的互作值.为提高小麦产量, 生产上应依据不同基因型品种的特性来确定施肥量和种植密度. 相似文献
29.
WARM is a model for rice simulation accounting for key biotic and a-biotic factors affecting quantitative and qualitative (e.g., amylose content, chalkiness) aspects of production. Although the model is used in different international contexts for yield forecasts (e.g., the EC monitoring and forecasting system) and climate change studies, it was never explicitly evaluated for transplanting, the most widespread rice establishment method especially in tropical and sub-tropical Asia. In this study, WARM was tested for its ability to reproduce nursery growth and transplanting shock, using data on direct sown and transplanted (both manual and mechanical) rice collected in 24 dedicated field experiments performed at eight sites in Jiangsu in 2011, 2012 and 2013. The agreement between measured and simulated aboveground biomass data was satisfactory for both direct sowing and transplanting: average R2 of the linear regression between observed and simulated values was 0.97 for mechanical transplanting and direct sowing, and 0.99 for manual transplanting. RRMSE values ranged from 5.26% to 30.89%, with Nash and Sutcliffe modelling efficiency always higher than 0.78; no notable differences in the performance achieved for calibration and validation datasets were observed. The new transplanting algorithm – derived by extending the Oryza2000 one – allowed WARM to reproduce rice growth and development for direct sown and transplanted datasets (i) with comparable accuracy and (ii) using the same values for the parameters describing morphological and physiological plant traits. This demonstrates the reliability of the proposed transplanting simulation approach and the suitability of the WARM model for simulating rice biomass production even for production contexts where rice is mainly transplanted. 相似文献
30.
播种期和品种对萝卜现蕾、抽薹和开花的影响 总被引:1,自引:0,他引:1
对冬性强弱不同的4个萝卜品种进行周年播种,以探讨其现蕾、抽薹和开花的响应。结果表明,从播种至现蕾、抽薹和开花所需的时间不仅品种间和播种期之间存在显著差异,而正品种与播种期之间的互作效应也达到极显著水平。播种后现蕾、抽薹时间越短,现蕾时叶片数也越少、初花期植株越矮小。在杭州的气候条件下,“白玉春”和“早春大根”周年播种在现蕾前均能够获得正常或基本正常的肉质根,但尽可能避免11月下旬至2月下旬;“一点红”只要在4月至11月初播种亦可在现蕾、抽薹前获得大小正常的肉质根;“短叶13”只有在6月下旬至9月下旬播种时方能在现蕾、抽薹前获得大小正常的肉质根。 相似文献