Response of maize root growth dynamics to drip irrigation amount
WANG Jun, LI Jiusheng*, LI Yanfeng, HAO Fengzhen, QIU Zhenjie
State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
Abstract：The spatial and temporal dynamics of root growth determines the ability of crop roots water uptake. Two-year continuous pot experiment was conducted to investigate the effect of irrigation amount on the dynamics of soil water content and root growth as well as the distribution in the soil profile. In this pot experiment, three irrigation levels were designed, i.e. 100%, 75% and 50% of crop water requirement ETc. The results showed that the root length density of maize decreased gradually with the increase of soil depth and horizontal distance from the dripper. The maize root length density varied during the growth stages, the minimum root length density at the jointing stage, the highest in the heading-milk stage, and then decreased in the late mature stage. Less difference of root length density was found among the treatments in the vertical direction in the jointing stage. The root length density of treatment 75%ETc at the depth of 0-40 cm was greater than that of treatments 50% and 100%ETc by 8% and 26% in the heading-milk stage, respectively. In the mature stage, the root length density at the depth of 0-60 cm of treatment 50%ETc was the highest. It was greater than that of trea tments 75% and 100%ETc by 51% and 40%, respectively. In the horizontal direction, root length density of treatments 50% and 75%ETcwere higher than that of treatment 100%ETc by 29% in jointing and heading-milk stages. In the mature stage, the root length density of treatment 50%ETcin the horizontal direction was the biggest. It was greater than that of 75% and 100%ETc by 52% and 40%, respectively.
[1]DARDANELLI J L, RITCHIE J T, CALMON M, et al. An empirical model for root water uptake[J]. Field crops research, 2004, 87: 59-71.[2]李久生, 张建君, 薛克宗. 滴灌施肥灌溉原理与应用[M]. 北京: 中国农业出版社, 2003.[3]SHIERLAW J, ALSTON A M. Effect of soil compaction on root growth and uptake of phosphorous[J]. Plant and soil, 1984, 77:15-28.[4]李仙岳,史海滨,龚雪文,等. 立体种植农田不同生育期及土壤水分的根系分布特征[J]. 农业机械学报, 2014,45(3):140-147. LI Xianyue, SHI Haibin, GONG Xuewen, et al. Root distribution in strip intercropping field under different growth period and different soil water[J]. Transactions of the CSAM, 2014, 45(3):140-147.(in Chinese)[5]GAO Y, DUAN A W, QIU X Q, et al. Distribution of root length density in a maize/soybean strip intercropping system[J]. Agricultural water management, 2010, 98: 199-212.[6]COELHO E F, OR D. Root distribution and water uptake patterns of corn under surface and subsurface drip irrigation[J]. Plant and soil, 1999, 206: 123-136.[7]LI X, SIMUNEK J, SHI H, et al. Spatial distribution of soil water, soil temperature, and plant roots in a drip-irrigated intercropping field with plastic mulch[J]. European journal of agronomy, 2017, 83: 47-56.[8]白有帅,贾生海,雒天峰. 覆膜滴灌条件下灌水量对玉米根系分布特征的影响[J]. 节水灌溉, 2016,11:19-22. BAI Youshuai, JIA Shenghai, LUO Tianfeng. Effect of irrigation on root distribution characteristics of maize under film drip irrigation[J]. Water saving irrigation, 2016,11: 19-22.(in Chinese)[9]李潮海,李胜利,王群,等. 不同质地土壤对玉米根系生长动态的影响[J]. 中国农业科学, 2004,37(9):1334-1340. LI Chaohai, LI Shengli, WANG Qun, et al. Effect of different textural soils on root dynamic growth in corn[J]. Scientia agricultura sinica, 2004, 37(9): 1334-1340.(in Chinese)[10]LEIB B G, CASPARI H W, REDULLA C A, et al. Partial rootzone drying and deficit irrigation of ′Fuji′ apples in a semi-arid climate[J]. Irrigation science, 2006, 24: 85-99.[11]SKAGGS T H, VAN GENUCHTEN M Th, SHOUSE P J, et al. Macroscopic approaches to root water uptake as a function of water and salinity stress[J]. Agricultural water management, 2006, 86: 140-149.
