Abstract:In order to determine the ecological factors for the fertility transition of photo-thermo-sensitive tassel vanishing line in maize, two lines of materials with stable sterility characteristics were used in this study with a optimized sowing date for seed production. Photo-thermo-sensitive tassel vanishing line in maizes I17, I478, Ptvt3 and Ptvt2 were selected as studied materials, and the maize self-inbred lines 478 and B73 as control materials. The field staged sowing experiment was studied in Liuyang City, Hunan Province, to analyze their male flower fertility and male ear traits, fertility and yield traits at nine sowing dates. The results showed that the main influencing factor for the fertility transition of maize photo-thermo-sensitive tassel vanishing line was the average daily high temperature at the seedling stage, and I17 was environmentally sensitive during the V2-V6 period; I478 was environmentally sensitive during the V2-V4 period. Ptvt3 was environmentally sensitive during the V2-V4 period and Ptvt2 environmentally sensitive period during V2-V5. I17 was suitable for self-crossing for seed production at sowing period 1, 8, 9, and for hybrid seed production as a two-line sterile line from sowing period 1 to 6. The I478 was suitable for self-crossing for seed production at sowing period 1, 2, and 8, and for hybrid seed production as a two-line sterile line from sowing period 5 to 7, while Ptvt3 was suitable for self-crossing for seed production at sowing stages 1, 8, and 9, and for hybrid seed production as a two-line sterile line at sowing stages 2 to 7. And Ptvt2 was suitable for self-crossing for seed production at sowing stages 1 and 2, and for hybrid seed production as a two-line sterile line at sowing stages 3 to 7. Photo-thermo-sensitive tassel vanishing line in maize Ptvt3 had the advantages of high reproductive yield and longer growth period compared with I17, I478 and Ptvt2, and Ptvt3 had the advantage of stable sterility characteristics, thus Ptvt3 was more suitable for production and application as a two-line sterile line.