Impact of water and nitrogen coupling on quality of greenhouse tomato with furrow irrigation under film
Impact of water and nitrogen coupling on tomato quality indicators (organic acids,soluble sugar,Vc,nitrate,sugar acid ratio) with furrow irrigation under film was studied in this paper by using multi-objective evaluation with principal component analysis.Two irrigation levels (1485 m3· hm-2 and 2080 m3· hm-2) and three N levels (225kg·hm-2,410 kg·hm-2 and 630 kg· hm-2) were used in this study.The results showed that irrigation and nitrogen amount as a single factor,in combination with water and nitrogen interaction,affected tomato quality indicators in different degrees.Increasing irrigation amount improved tomato fruit organic acids,nitrate content ; while excess or lack of nitrogen reduced tomato fruit soluble sugar content,Vc content,sugar acid ratio.Nitrate content in the fruit increased with increase of nitrogen,decreased with increase of irrigation volume.By using multi-objective evaluation of tomato quality indicators with principle component analysis,we draw conclusion that low water medium nitrogen process (W1485N410)had highest colligate index,on other hand,high water high nitrogen process (W2080N630) had the lowest one.
furrow irrigation under membranewater and nitrogen couplingtomatoqualityprincipal component analysiscomprehensive evaluation