不同密度和氮素水平对设施袋培番茄产量、品质及冠层结构的影响

探讨密度和氮肥与设施袋培番茄产量、品质及冠层结构的关系。以番茄品种‘惠裕’为试材,设置3个密度水平(常规密度D1:4株/m~2、D2:6株/m~2、D3:8株/m~2),4个施氮量水平(常规氮肥N1:12 174mg/株、N2:11 581mg/株、N3:10 989mg/株、N4:10 396mg/株),共12个处理。结果表明,D1和D2条件下,番茄产量随氮肥的减少而减少,D3条件下,产量则随氮肥的减少呈现先增加后降低的趋势;N1条件下,番茄产量随密度的增加逐渐降低,N2、N3、N4条件下,番茄产量则随密度的增加而增加;番茄果实中可溶性硝酸盐、可溶性蛋白、可溶性糖以及维生素C质量分数在相同密度条件下,均随氮肥的降低而降低;相同氮肥条件下,均随密度的增加而增加;密度相同时,番茄冠层内透光率随施氮量的降低而升高,消光系数则随施氮量的降低而降低;氮肥相同时,随着密度的增加,番茄冠层内透光率呈递减趋势,而消光系数则呈递增趋势。设施袋培番茄选择密度8株/m2、施氮量11 581mg/株为最优组合。

Effect of Plant Density and Nitrogen Fertilizer Rate on Yield,Quality and Canopy Structure of Greenhouse Tomato Cultivated on Organic Substrate Bag

This study aims at discovering the relations of density and nitrogen fertilizer with the yield,quality and canopy structure of tomato cultivated by organic substrate in bag. The experiment had 12 treatments,including three density levels (control treatment,D1,4 plant/m; D2,6 plant/m; D3,8 plant/m) and four nitrogen fertilizer levels (control treatment,N1,12 174 mg/plant; N2,11 581 mg/plant; N3,10 989 mg/plant,N4,10 396 mg/plant). The results indicated that the yield of tomato decreased with the decreasing of nitrogen fertilizer under D1 and D2 levels,while it showed a trend of first increase and then decline under D3 level. Under N1 condition,the tomato yield reduced gradually with the increasing of density levels,but tomato yield consistently increased as the increase of density when nitrogen fertilizer were N2,N3,and N4. The treatment with the same planting density,the mass fraction of nitrate,soluble protein,soluble sugar and vitamin C in tomato fruits all decreased as the decrease of nitrogen fertilizer. At the same nitrogen fertilizer level,increasing in density promoted accumulation of fruit soluble protein,soluble sugar and vitamin C,however,the mass fraction of nitrate showed a trend of decline. Light transmission was enhanced with the decline of nitrogen fertilizer under the same density levels,but the extinction coefficient lowered with the decline of nitrogen fertilizer. At the same level of nitrogen fertilizer,light transmission reduced with the increasing of density,while the extinction coefficient showed a trend of increase. In conclusion,seting of 8 plant/m and 11 581 mg/plant is the optimal choice for greenhouse tomato cultivated on organic substrate bag.