潮汐灌溉营养液浓度分段设定对番茄穴盘苗生长的影响

以中杂302为试材，将番茄穴盘苗生长发育分为5个阶段(Ⅰ：播种至出苗；Ⅱ：出苗至子叶平展；Ⅲ：子叶平展至二叶一心；Ⅳ：二叶一心至三叶一心；Ⅴ：三叶一心至四叶一心)，分段设定9个营养液浓度组合，研究潮汐灌溉条件下营养液浓度分段设定对番茄穴盘苗生长发育、养分积累量及利用率的影响。结果表明：在第Ⅰ阶段，灌溉1.0×营养液，番茄穴盘苗出苗率最高，播种后第7天比清水对照提高了7.71百分点，显著高于其他处理；当营养液浓度设定为Ⅰ阶段0.25×、Ⅱ阶段0.25×、Ⅲ阶段0.5×、Ⅳ阶段1.5×、Ⅴ阶段1.5×时(处理9)，番茄穴盘苗第Ⅴ阶段的株高、茎粗、叶面积、总根长、根体积、根表面积、根平均直径、茎叶及根鲜质量和干质量、壮苗指数等指标最优，穴盘苗干质量增长速率最高；N、P、K的吸收积累量最高，分别为15.8、10.1、21.0 mg · 株^-1，利用率分别为14.35%、6.10%、15.92%。

Effect of Nutrient Solution Concentration Block Setting on Growth of Tomato Plug Seedling under Ebb-and-flow Irrigation System

Taking‘Zhongza No.302’as test material,this study divided the growth and development of tomato plug seedlings into 5 stages(stageⅠis from sowing to seedling emergence;stageⅡis from seedling emergence to cotyledon spreading;stageⅢis from cotyledon spreading to seedling with 2 leaves;stageⅣis from seedling with 2 leaves to 3 leaves;and stageⅤis from seedling with 3 leaves to 4 leaves).Nine nutrient solution concentrations were set in sections.Studies about the effects of nutrient solution concentration block setting on growth and development,nutrient accumulation amount and utilization rate of tomato plug seedlings under ebb-and-flow irrigation system were carried out.The results showed that in stageⅠwith irrigation 1.0×nutrient solution concentration,the plug seedling emergence rate was the highest,which was increased by 7.71%than that of the contrast water on the 7th day after sowing.This was obviously higher than those of the other treatments.When the nutrient solution concentration was set as 0.25×in stageⅠ,0.25×in stageⅡ,1.0×in stageⅢ,1.5×in stageⅣand 1.5×in stageⅤ(treatment 9),the growth indexes of plug seedling including plant height,stem thickness,leaf area,total root length,root volume,root surface area,root average diameter,dry and fresh weights of stem leaf and root,and strong seedling index,etc.were the best,and the dry weight growth rate of plug seedlings was the highest.The uptake and accumulation of N,P and K were the highest.They were 15.8,10.1,21.0 mg·plant^-1,respectively,and the utilization rates were 14.35%,6.10%and 15.92%,respectively.