Effect of seed rate on upland cotton (Gossypium hirsutum) seedling emergence

The most important factor to achieving profitable cotton yields is obtaining a uniform stand of healthy and vigorously growing seedlings. Cotton seedling emergence highly depends on the number of seeds that are planted on the same planting station. The cotton seedling stalk is weak and may fail to push up and crack the soil in order to emerge. Therefore several seedlings put together may use the power of numbers to push out of the soil. Cotton seedling emergence percentage and stand are closely related to seed rate. In Zimbabwe the question of which seed rate is optimal took centre stage in input negotiations between contractors and farmers. A research project was therefore conducted at Cotton Research Institute, Tokwane, Mahuwe, and Muzarabani communal areas during two seasons of 2014 to 2015 in order to determine the effect of seed rate on cotton seedling emergence. The experiment was laid in a randomized complete block design with eight treatments of varying seed rates that ranged from two to nine seeds per planting station and with four replications. Results showed significant differences on stand counts among seed rates. At C.R.I and Mzarabani communal area three seeds per station achieved better stand counts while at Tokwane, five seeds per station resulted in better stand counts. In Mahuwe communal area, six seeds per station performed better. However, six seeds per station was the median seed rate that produced the highest stand counts across sites and across seasons. It is therefore recommended that farmers can plant three up to six seeds per station depending on environmental conditions Key words: Cotton, seed rate, seed, stand counts, emergence, seedling.