Evaluation Of Maize Drought Loss Based On Crop Growth Model

Meteorological disasters of agriculture have a great impact on grain yield, and the simulation of crop growth and development by using crop growth simulation model has become one of the hot spots in the present research. According to the historical data and experimental data (including the data of corn staging sowing experiment and drought stress experiment), This paper conducts the drought loss assessment of maize in the west of Liaoning Province using WOFOST model, and analyzes the influences in typical drought year. The main conclusions are:(1) Research on single point localization and regionalization of WOFOST modelUsing the data of plentiful rainfall year and drought stress experiments of maize in Jinzhou area, the parameters of WOFOST model are adjusted. Then the development and production data in the west of Liaoning Province are used to examine the WOFOST model to achieve the localization of WOFOST maize growth models in western Liaoning area.(2) The effects of drought on the growth and yield of MaizeEffects of the summer drought in 2015 on silking stage is more serious than the effect on tasseling stage, caused tasseling date 1-14d delayed than normal year, silking date postponed 5-23d, days of tasseling-silking interval increased to 3-15d. The drought also caused 24.03% of maize failing tassel,37.9% failing silk after tassel and 49.21% did not growth normally. Drought inhibited the photosynthetic traits and the growth of stems, accelerated the fade of leaf. The drought inhibited not only the accumulation of nutrients in stems, but also the transportation of nutrients from stems to gains, finally affected the distribution of dry matter, resulted in increases of the proportion of leaf weight and stem weight, and decreases of the proportion of panicle weight. Drought is unfavorable to maize growth, and lead to yield decreased significantly. Different effects occurred on maize of different sowing dates, the damage to early-sowing maize (impact tasseling-silking stage) was more serious than that of late-sowing (impact jointing stage). Maize of various sowing date can growth normally under irrigation. And growth period, plant characteristics and dry matter distribution and so on were similar to those in the normal year.(3) Evaluation of maize drought loss in western Liaoning based on WOFOST modelThe WOFOST model was used to simulate the potential production of maize of different sowing date in western Liaoning area in 2015. The potential productiion decreased from northwest to southeast with an average value of 11491 kg/ha. The maximum value of potential production among different sowing treatments was that for sowing at May 30 (12247kg/ha). Potential production of late sowing treatments was higher than those of early sowing. The influence of drought on maize productions of different-date sowing treatments was also simulated. The maximum production was that sowing at May 20 (4760kg/ha). The geographical distribution showed the feature that production generally decreased from west to east and the average production was 4128kg/ha. Lower production occurred in Fuxin and Jinzhou area (<3000 kg/ha), while higher production occurred in western Huludao and Chaoyang area. The drought loss of maize production in 2015 was obtained by subtracting actual production from potential production. The results showed that the average loss of different-date sowing treatments was 7363kg/ha. The loss generally increases from west to east. The maximum loss happed to the treatments of sowing at May 30 with value of 8151kg/ha. The loss in Fuxin and Jinzhou area were higher (>8000 kg/ha). Lower loss occurred in western Huludao and Chaoyang area. Above simulation using WOFOST model indicated that the suitable sowing date is about May 10 and the maize has the lowest drought loss of 6894 kg/ha.