比较不同时期 meaning in English

comparing time periods

This experiment was designed according to the special soil moisture in the north in china as well as the different water requirements in the different growth periods of the maize . the author put forward a practical technique by comparing the water - supply conditions in the different periods of time and ensuring the growth target and the yield target under the best water - supply condition
针对北方旱区土壤水分运动存在冬季缓慢散墒、春季进入强烈跑墒期以及玉米在不同生长期需水差异这一特点，试验设计提出了节水渗灌这一技术的田间试验方案，比较不同时期的供水状况，最后确认在最佳的供水条件下的玉米生长指标及产量指标，提出一套较实用的玉米渗灌节水生产技术。