Cotton (Gossypium hirsutum L.) seedling root growth in response to low temperatures.

摘要

Cotton (Gossypium hirsutum L.) is often planted into cool conditions in the Mid-south, which are harmful to seedling development. Four diverse cultivars, Acala Maxxa, Stoneville 4892BR, Tamcot Sphinx and Fiber Max 966 were examined in growth pouches, PVC tubes at 15/20°C, 15/25°C, 15/30°C, 15/35°C, 15/40°C, 15/45°C, and 28/28'C, plus in the field for genotypic differences. In the growth pouch study, Tamcot Sphinx was significantly higher in taproot length. Stoneville 4892BR had superior root branch intensity at 15/35°C and 15/45°C in the PVC tube study. In the early planting in the field, Stoneville 4892BR exhibited higher lateral root number and lateral root length, while Acala Maxxa showed similar advantages during the normal planting. Stoneville 4892BR and Acala Maxxa also had the highest total dry weight production of all cultivars in the field, showing that genotypic root differences exist among cotton cultivars for a healthier, more vigorous seedling in cooler planting conditions.