Transplanting of Maize During the Winter in India A. S. Khehra, H. S. Brar, R. K. Sharma, B. S. Dhillon,* and V. V. Malhotra ABSTRACT Maize (Zea mays L.) cultivation during the winter is a new crop- ping practice in North India. In this cropping system, maize has slow seedling growth associated with low winter temperatures. If the crop can be grown in a nursery during this slow-growth period and then transplanted, the crop duration in the main field is shortened. Therefore, the present study was conducted to determine if maize could be successfully transplanted to the field. Other objectives were to evaluate the effect of seedling age, and date and method of trans- planting. Experiments were done in the field during two or three winter seasons at two locations. Among the transplanting treat- ments, 40-d-old seedlings transplanted on 24 December and 60-d- old seedlings on 16 January resulted in the highest grain yields. Grain yields from these transplantings were 92 to 94% (5314-5402 kg ha" 1 ) of the yield of the crop direct seeded on 9 November (5743 kg ha" 1 ), the optimum sowing time. Grain yield was significantly reduced when younger (up to 20 d) or older (up to 80 d) seedlings were used, with drastic reduction in the latter case. Transplanting of 60-d-old seedlings on 24 December and 80-d-old seedlings on 16 January yielded only 10 to 12% as compared with the best trans- plantings. Delayed transplanting (6 February) also decreased grain yield. The comparisons between methods, transplanting on the southern slope of the east-west ridge or on a flat seed bed, showed that the former improved grain yield. The present study indicates that maize can be successfully produced by transplanting 40-d-old seedlings on 24 December and 60-d-old seedlings on 16 January, and that transplanting should preferably be done on the ridged seedbed. M AIZE is mostly grown in the warmer parts of tem- perate regions and in the humid-subtropical areas of the world. Its growth in other areas is limited by cool temperatures and the length of the frost-free period (Shaw, 1977). In India, maize is traditionally cultivated during the monsoon season (May-Octo- ber), a period of high temperatures and rainfall. In Punjab (North India) the average daily temper- A.S. Khehra, H.S. Brar, and R.K. Sharma, Dep. of Plant Breeding, Punjab Agric. Univ., Ludhiana-141 004, India; B.S. Dhillon, Inst. of Plant Breeding, Seed Sci., and Population Genetics, Univ. of Hohenheim, D-7000 Stuttgart 70, Fed. Rep. Germany; and V.V. Malhotra, Himachal Pradesh Krishi Vishva Vidyalaya, Regional Res. Stn., Bajaura-175 125, India. Contribution from the Dep. of Plant Breeding, Punjab Agric. Univ., Ludhiana. Received 28 Dec. 1987. Corresponding author. Published in Agron. J. 82:41-47 (1990). Published January, 1990