Effects of plant density on boll retention and yield of cotton

Authors: McCarty, Jack; Jenkins, Johnie; Hayes, Russell - Russ; Wubben, Martin

Submitted to: American Journal of Plant Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/28/2017
Publication Date: 3/31/2017
Publication URL: http://handle.nal.usda.gov/10113/5678124
Citation: McCarty Jr, J.C., Jenkins, J.N., Hayes, R.W., Wubben, M. 2017. Effects of plant density on boll retention and yield of cotton. American Journal of Plant Sciences. 8:891-906.

Interpretive Summary: The number of cotton plants being grown per unit of land area has gained attention due to the cost of seed with value added traits. The current research investigated boll retention, yield, and yield components of cotton grown with reduced stands of 20% to 40% from the standard of drilling four seeds per foot of row. Five field experiments were conducted from 2012 – 2014 using eight treatments. Yield, yield component, and plant map data were collected. The plant one-row skip one-row treatment resulted in yield losses across all five experiments compared to the standard. A stand reduction of 20% did not result in lower total yields; however, each plant in these treatments had to produce two additional bolls to maintain yield. Treatments which had at least 2 foot skips, 40% stand reduction, resulted in lower yields. Minor affects were seen for boll weight, and lint percentage. The standard produced 67% of its yield from position1 bolls compared to about 50% for treatments with reduced stands. Reduced stand treatments produced about 20% of their yield on vegetative branches compared to 10% for the standard. This study suggests that with precision planting equipments opportunities exist to reduce seed rate and maintain yield; however, many production risk factors must also be considered before a reduced seeding rate is adopted.

Technical Abstract: The number of cotton, Gossypium hirsutum L., plants being grown per unit of land area has gained attention due to the technology fees associated with seed containing value added traits. The current research investigated boll retention, yield, and yield components of cotton grown with reduced stands of 20% to 40% from the standard of drilling four seeds per 30.5 cm of row. Five field experiments were conducted from 2012 – 2014 using eight treatments arranged in a randomized complete design in six row plots with six replications. Yield and yield component data were collected. The plant one-row skip one-row treatment resulted in significant yield losses across all five experiments compared to the standard. Treatments with 20% stand reductions did not result in lower total yields; however, each plant in these treatments had to produce two additional bolls to maintain yield. Treatments which had at least 61 cm skips, 40% stand reduction, resulted in lower yields. Treatments had minor affects on boll weight, and lint percentage. The standard produced 67% of its yield from position1 bolls compared to about 50% for treatments with reduced stands. Reduced stand treatments produced about 20% of their yield on monopodial branches compared to 10% for the standard. This study suggests that with modern precision planting equipments opportunities exist to reduce seed rate and maintain yield; however, many production risk factors must also be considered before a reduced seeding rate is adopted.