Study on Regulation Effect of Subsurface Drip Irrigation on the Growth of Tomato in Arid Area

In this paper,the regulation effect of subsurface drip irrigation on the growth of tomato plants is researched after carrying out a 3-year field experiment.The irrigation ways included the surface drip irrigation(DI) and subsurface drip irrigation(SDI),the field moisture capacities of(80 ± 5) %,(60 ± 5) % and(40 ± 5) %(DI1,DI2 and DI3) in soil depth of 0-60 cm were designed for the surface drip irrigation,and SDI1,SDI2 and SDI3 for the subsurface drip irrigation.The results show that the effects of both surface drip irrigation and subsurface drip irrigation on the biomass and length density of tomato roots were not significant after florescence,but significantly increased at full bearing stage under subsurface drip irrigation,and the distribution of tomato roots under subsurface irrigation was obviously evener than that under surface drip irrigation.The growth of overground part of tomato plants under deficient subsurface drip irrigation(SDI2 and SDI3) was obviously lower than that under deficient surface drip irrigation(DI2 and DI3) after florescence,but the situation was contrary at full bearing stage.For the moderate drought,the fruit weight,fruit number and water utilization efficiency under subsurface drip irrigation were obviously higher that that under surface drip irrigation.For the sufficient soil moisture content,there was no significant difference in the growth of tomato plants and tomato yield between subsurface drip irrigation and surface drip irrigation;for slight drought,however,subsurface drip irrigation promoted significantly the growth of roots and overground part of tomato plants,and both the water utilization efficiency and tomato yield were obviously increased.