Early maturing Bt cotton requires more potassium fertilizer under water deficiency to augment seed-cotton yield but not lint quality

Abstract

Exhaustive crops such as cotton require potassium (K) in copious amounts as compared to other crops. High yielding cultivars in cotton-wheat cropping system, have further increased its demand in cotton growing areas of Pakistan. As cotton is grown in arid and semiarid areas, therefore often prone to water deficiency. The reproductive growth particularly flowering and boll setting are highly sensitive to low soil water potentials, where enough K supply can play a vital role. In this two-year field studies, three cultivars (early, mid and late maturing) were cultivated at two K fertilizer levels 100, 200 kg K ha −1 along with control with no K fertilizer application at two irrigation levels. In first irrigation level, water was applied as per full irrigation schedule, while in water deficit irrigation water was applied at deficit irrigation schedule started after flowering till harvesting. It has been revealed that K application has impact on boll setting as well as seed cotton yield, however early and mid-maturing cultivars are more responsive to K fertilization. Furthermore, irrigation level had significant impact against K fertilization and relatively better response was observed in deficit irrigation as compared to full irrigation. Nevertheless, fiber quality parameters were unaffected by K fertilization. Considering the best benefit cost ratio under water deficiency, it is concluded that 100 kg K 2 O ha −1 should be applied at the time of seed bed preparation for economical seed-cotton yield of early maturing Bt cotton.

Efficacy of fertilizing method for different potash sources in cotton (Gossypium hirsutum L.) nutrition under arid climatic conditions

“…Importantly, foliar application will not be the best option always, because it will not fulfil the nutritional requirements under K-deficient conditions. In this study soil had >150 mg K kg -1 soil which is considered as sufficient K content for most of the crops; however, foliar K application contributed some extra benefits due to timely and direct K application when required by plants in very large amounts and soil supply of K may not be sufficient [29,30].…”

“…Indeed, K 2 SO 4 contains sulfur besides K, which enhances protein synthesis, enzyme functioning, and cell elongation [26], ultimately improves crop yield as observed in this study. Moreover, the use of K 2 SO 4 has been found to improve vegetative growth [27], lint yield, and quality of cotton [28,29,30] through reduction in the number of unopened bolls and an improvement in the number of opened bolls per plant as compared with other K sources. The highest seed-cotton yield due to foliar applied K 2 SO 4 in this study might be attributed to the improvement in boll weight, number of opened bolls per plant and more number of monopodial and sympodial branches (Tables 2 and 4).…”

Long-Term Impacts of Different Cropping Patterns on Soil Physico-Chemical Properties and Enzyme Activities in the Low Land Plain of North China

“…Spring cotton had higher soil K at the 0-20 cm depth, probably due to its high exhaustive and sensitive nature, where it requires abundant amounts of K [65,66]. Hence, there was more deposition of K in the upper layer from mining in the lower soil depths [67,68].…”

Determination of the Best Controlled-Release Potassium Chloride and Fulvic Acid Rates for an Optimum Cotton Yield and Soil Available Potassium

“…Cotton exhibits a high potassium demand, and potassium nutrition plays a key role in the determination of the cotton yield and fiber quality ( Hatam et al, 2020 ). Potassium is an important element for crop growth and development that plays a vital role in maintaining the cell osmotic pressure balance ( Zahoor et al, 2017 ), improving the stomatal movement, ensuring enzyme activity, optimizing the photosynthetic performance, promoting the transport of assimilates ( Hafeez et al, 2018 ), and improving plant resistance to biotic and abiotic stresses ( Shahzad et al, 2019 ). In addition, potassium can improve the utilization rate of nitrogen fertilizer, promote the growth of roots, stems, leaves, and reproductive organs of cotton plants, prolong the functional period of leaves, and prevent premature aging ( Hu et al, 2017 ).…”