【摘要】 【目的】利用田间试验,在日光温室内研究滴灌施肥灌溉系统运行方式和施肥频率对番茄产量、品质及根系生长的影响。【方法】系统运行方式包括不同灌水和施肥次序组成的3种方案;施肥频率取每周1次,2周1次和4周1次3个水平。在生育期内对番茄的光合速率等参数进行观测,收获后测定番茄的根密度、果实的品质,并统计产量。【结果】施肥频率对番茄的产量影响显著,施肥频率从4周1次增加到每周1次时产量显著增加(P=0.012)。随着施肥次序向后推移,番茄的产量有下降的趋势,但差异未达到显著水平。施肥频率和运行方式对番茄各项品质的影响都不显著。施肥频率对根密度的影响主要是引起各土层根密度大小的变化,运行方式则对各土层根长占整个剖面根长总和的比例产生影响。在分析了运行方式和施肥频率对光合速率影响的基础上,计算整个生育期内的光合累积量,用来分析光合作用的变化对产量的影响。结果表明,产量和光合累积量有显著的相关性(P=0.043)。【结论】从提高产量和品质的角度看,施肥频率取每周1次较为适宜,滴灌施肥灌溉过程中的施肥时段应尽量前移。更多还原

【Abstract】 【Objective】Field experiments were conducted in a solar-heated greenhouse to investigate the effects of drip fertigation strategies and frequencies on yield, quality and root growth of tomato. 【Method】Three fertigation strategies with different orders in which water and nutrients were applied for an irrigation event and three fertigation frequencies of weekly, fortnightly and once every four weeks were tested. Photosynthetic rate was measured during the growing season. Yield was recorded for each harvest and the root length density was measured after the final harvest. 【Result】Fertigation frequencies influence the tomato yield significantly. Yield increased significantly with the increase of fertigation frequency (P=0.012) and decreased as the fertigation time was transferred towards the end of an irrigation cycle. Both fertigation strategies and frequencies had an insignificant effect on the quality of tomato. Root length density varied with fertigation frequencies, and the ratio of root length for different soil layers to the total root length in the profile varied with fertigation strategies. The effects of strategies and frequencies on photosynthetic rate were investigated. The accumulation of photosynthetic rate in the whole growing season was calculated for analyzing the relationship between yield and photosynthesis. The results demonstrated that the yield was highly correlated to the accumulation of photosynthetic rate. 【Conclusion】 For the sake of improving yield and quality of tomato, fertigation weekly and the strategy of applying fertilizer as early as possible in the whole irrigation schedule were recommended.更多还原