NGHIÊN CỨU ẢNH HƯỞNG CỦA THỜI VỤ, MẬT ĐỘ TRỒNG ĐẾN NĂNG SUẤT VÀ CHẤT LƯỢNG GIỐNG NGÔ NẾP LAI HN88 TẠI THÁI NGUYÊN

Two experiements were carried out at Thai Nguyen city during 2013 and 2014. The first experiement studies sowing time of maize varieties HN88 including 5 treatments with diffirent sowing times: Feb. 9, Feb. 19, March 1, March 11 and March 21. The second experiemnt studies distance of seed sowing and plan density with 5 treatments: (1) seed sowing 50  30cm with density of 67,000 plants per hecta, (2) 50  35 cm; 57,000 plant/ha, (3) 60  30 cm; 56,000 plant/ha, (4) 60  25 cm; 67,000 plant/ha, (5) 70  25 cm; 57,000 plant/ha. Results of the study shown that growth time of crop is longer if sowing time is earlier. Early sowing seeds in Spring season resulted in increasing yield and seed quality (the best sowing time is from Feb.9 to Feb.19). Sowing time has effects on growth of plant, crop yield and dry seed quality of sticky maize variety HN88. When reducing distance of seed sowing resulted in increasing fresh yield and dry yield compared to traditional seed sowing. The highest yield is found at plant density of 67,000 plants/ha (distance of seed sowing 50  30 cm và 60  25 cm). Seed quality of maize did not affect by distance of seed sowing and plant density.