Abstract
A field experiment was conducted to assess the effectiveness of fruiting positions along sympodia under varying levels and sources of potassium (K) fertilizer on field-grown cotton in an arid environment. Treatments consisted of four rates of K (0, 62.5, 125.0, 250.0 kg K ha− 1) and two types of K (K2SO4 and KCl). Cotton cultivar S-12 (Gossypium hirsutum L.) was used as a test crop. Plant mapping data showed that the total number of fruiting positions, number of intact fruit on sympodia/monopodia, and percent of bolls per position on sympodia differed greatly under different doses of K fertilizer. The percentage of fruit retention was markedly improved under increasing doses of K fertilizer as compared with the K-unfertilized treatment. The percent survival of harvestable bolls for the first five positions along sympodia at the end of the season was 30%, 25%, 18%, 13%, and 8%, respectively. Potassium fertilization stimulated cotton crop in lengthening sympodial branches and retaining more fruit on the first three positions and also at the bottom of the plant during the early reproductive phase. The fruiting pattern was 2–3 and 6–7 d vertical and horizontal fruiting interval, respectively.
Notes
**Significant at the 0.01 level.
**Significant at the 0.01 level.