旱地小麦产量及其构成因素灌溉效应的模拟分析

为揭示灌水时期与灌水量对黄土丘陵区小麦产量及其构成因素的影响规律，依据黄土丘陵典型区域定西1971-2016年气象数据及定西市安定区凤翔镇安家沟村2016年大田试验数据，利用APSIM（Agricultural Production Systems Simulator）平台，动态模拟各灌溉处理下的小麦生长发育过程，并对各灌溉响应进行模拟分析。结果表明：小麦全生育期需水量为315.25 mm，各生育阶段需水量为播种~出苗21.13 mm、出苗~分蘖26.60 mm、分蘖~拔节33.27 mm、拔节~孕穗77.17 mm、孕穗~开花69.31 mm、开花~灌浆36.19 mm、灌浆~成熟51.58 mm。为提高产量，最佳灌水时期应在播种至拔节，灌水量不宜超过60 mm；开花前各生育阶段灌溉处理都明显提高了单位面积籽粒数量，其中以分蘖~拔节阶段（TS）最明显，拔节~孕穗阶段（JS）灌水量不宜超过80 mm、孕穗~开花阶段（BS）灌水量不宜超过20 mm。开花~灌浆阶段（FS）灌水量40 mm对粒重增加的促进作用最明显。

Simulation analysis of irrigation effect on yield and its constitute factors of dryland wheat

In order to reveal the influence of irrigation time and amount on yield and its constituent factors of wheat in the hill-gullied region of the Loess Plateau, using the field experimental data in Anjiagou village, Fengxiang town, Anding district of Dingxi in 2016 and the meteorological data in Anding district of Dingxi from 1971 to 2016 with APSIM(Agricultural Production Systems Simulator) platform, the growth process of wheat were dynamically simulated under different irrigation treatments and the effect of each irrigation treatment were analyzed. The results showed that the water requirements of wheat during whole growth period was 315.25 mm. The water requirements for different growth stages were different that was 21.13 mm from sowing to seeding, 26.60 mm from seeding to tillering, 33.27 mm from tillering to jointing, 77.17 mm from jointing to booting, 69.31 mm from booting to flowering, 36.19 mm from flowering to filling, and 51.58 mm from filling to maturation. To improve yield, the best irrigation stage should be from sowing to jointing, and the irrigation amount should not be more than 60mm. Irrigation treatment at each growing stage before flowering significantly increased the grain number per unit area, among which it was most obvious from tillering to jointing (TS). The irrigation amount from jointing to booting (JS) and booting to flowering (BS) should not exceed 80 mm and 20 mm, respectively. The optimum irrigation treatment for increasing grain weight was from flowering to filling (FS) and the irrigation amount was 40 mm.