Effects Of Nitrogen Forms On The Growth Of Tomato Under Controlled Root Divided Alternative Irrigation

In this experiment,we used the materials of tomato,carried out the experiment in the pot,analyze morphological indexes、physiological indexes、root index、yield、quality and wateruse efficiency and mineral elements of tomato in growing process, find out the influence ofnitrogen form (nitrate nitrogen, ammonium nitrogen) supply to growth and regulatingmechanism of tomato under the controlled root-divided alternative irrigation，in order toprovide theoretical basis and practical guidance for the alternate root zone irrigation waterand nitrogen efficient utilization.The results show that:Ammonium nitrogen treatment is conducive to the early growth of tomato,but the latenitrate nitrogen treatment is preferred. plant height and leaf area of alternate partial root-zoneirrigation are smaller than Normal irrigation. but alternate irrigation（60%θf）stem diameter ofalternate irrigation（60%θf）can increased in the later growth. If the moisture control issuitable, it is not big influence on the tomato plant’s morphological indexes,but excessivemoisture forces can have the disadvantageous influence to crops’ growth, and finally causethe serious under production.Different nitrogen forms and irrigation treatment can directly affect other physiologicalchanges in plants, indirectly affect plant photosynthesis, Alternate irrigation treatment inreduced stomatal conductance and transpiration water loss, at the same time, thephotosynthetic rate did not fall, thus improving the water use efficiency, and the tomato withalternate irrigation treatment can enhance the ability to adapt under adversity stress.Nitrate nitrogen treatment can improve the yield of fruit in the later growth of tomato.The fruit yield of alternate irrigation all to be lower than normal irrigation, but is not obvious,as a whole to improve the quality of tomato fruit. Different nitrogen forms effect thedifference of fruit quality. nitrate nitrogen treatment can improve the fruit nutritional quality,and increase the nitrate content of fruit.The sugar acid ratio of ammonium nitrogen treatmentis fall reduce the flavor quality of the fruit.Nitrate nitrogen treatment produce profound effect of the root growth in the middle andlater growth of tomato. The growth of root system did not increase with the increase ofirrigation water. Properly reduce soil moisture in a certain extent stimulated the growth ofroot system, cause increased root activity, but the excessive moisture forces was seriously inhibits the growth of tomato root system.In summary, the treatment with alternate irrigation compare with the normal irrigation.the output drops not remarkably, and the quality of tomato has some enhancement, and it hasthe effect of obvious saves water effect, Combined with this phenomenon of the nitratenitrogen has promoting effect on the middle and later growth of tomato. Under thisexperiment condition, the conclusion is: Suitable for nitrate nitrogen and alternate irrigationtreatment combination was suggested for higher yield, better quality of tomato.