| Based on the premise of efficient utilization of light and heat resources in the cold climate areas of Jilin province,the purpose of this study was to introduce medium-mature maize varieties and increase the selection range of maize varieties in the eastern region.The medium-ripe corn variety Fumin 985 was used as the test material to study the soil temperature,growth index,filling rate and The impact of yield,on the premise of clarifying the yield increase effect of medium-mature corn varieties after plastic film planting,cleared the suitable seeding time of medium-mature maize varieties under film-covering conditions,with a view to more reasonable use of light and heat resources,as the high-yield cultivation provides a theoretical basis of maize in the eastern of Jilin province.In 2018,Fumin 985,a medium-maturity maize variety,was planted with film mulching,and Xinhe 916,a precocious variety,was used as a control,on this basis,the yield,ground temperature,filling rate and growth index were measured.In 2018 and 2019,four sowing dates were set,namely,Ti(April 30),T2(May 6),T3(May 12)and T4(May 18),with the medium-maturity maize variety Fumin 985 as the test material,sampling and measurement shall be carried out according to the measurement requirements of each period.The main results of this study are as follows:1.Film mulching can significantly increase the soil temperature and volumetric soil water content during the whole growth period of corn.The daily average soil temperature covered by degradable mulch was 6.4%higher than bare land,and the accumulated temperature was 163.9℃ higher than that bare land.After plastic film mulching,the volumetric soil water content higher than that bare land.2.The plant height and spike position of coated maize were 274.1cm and 95.4cm,respectively,which were 10.8%and 29.5%higher than that of bare field maize.3.When the grouting rate reaches the largest growth of film mulched corn(Wmax)was 10.46g,28.8%higher than that of corn planted in bare land,and grouting duration(T)was 37.35d,8.87d longer than that of corn planted in bare land.4.The population growth rate(CGR),net assimilation rate(NAR)and ear growth rate(EGR)of film-coated corn during the entire growth period were 157.6 gm-2d-1,36.5 gm-2d-1,and 80.5 gm-2d-1,respectively,which were 27.4%higher than that of bare corn 11.1%and 14.0%.5.The hundred grain weight,number of rows per ear and number of grains per ear of film-coated corn were 24.6g,17.2 rows and 622.6 grains,respectively,which were 21.8%,27.4%and 8.6%higher than that of the control.The yield was 43%higher than that of the control.6.In 2018 and 2019,the average corn yield sown on April 30 was 12,144.65 kg/hm2,which was significantly higher than that of other sowing dates.Therefore,in the cold climate area of eastern Jilin Province,the medium maturity corn varieties can be introduced through film mulching planting,and the seeds can be sown from the end of April to the beginning of May.At the same time of increasing the accumulated temperature in the growth period,it can gain time for the increase of 100 kernel weight and dehydration in the later period,and realize the comprehensive improvement of stress resistance,yield and quality of corn,so as to achieve the purpose of high yield and efficiency. |
