Differential Response of Two Cotton Cultivars to Fertilizer and Soil Potassium

Abstract

Cotton (Gossypium hirsutum L.) cultivars have considerable yield differences on vermiculitic soils where late‐season K deficiency occurs in California. A 2‐yr field study was conducted to evaluate cultivar differences in K use efficiency (defined as higher yield with a limited K supply) in relation to K uptake, K partitioning, and critical internal and external K requirements. The experiment had a split plot design with fertilizer‐K addition levels as mainplots, two cultivar subplots, and 10 blocked replications. Without K addition, yield was 29% (1986) and 35% (1987) greater in the K‐use‐efficient cultivar. Cultivar yield differences reflected greater boll retention at later fruiting positions, but was not related to differences in partitioning of K between vegetative and fruiting structures. When K supply was not limited, cultivar yields were similar. Yield of both cultivars was closely associated with leaf K concentration and soil K availability, but response curves indicated a lower leaf and soil K requirement for the K‐use‐efficient cultivar. The K‐use‐efficient cultivar had a higher K uptake rate during fruit development and greater total K accumulation, particularly at low soil K levels. Defining the physiological bases for such large genetic variation in K use efficiency will help to identify why the cotton plant is more sensitive to K limitation than other crops and will aid breeding efforts to develop germplasm more tolerant of a limited soil K supply.

Cotton root and shoot response to localized supply of nitrate, phosphate and potassium: Split-pot studies with nutrient solution and vermiculitic soil

“…Potassium-efficient GChl0 can accumulate 38% more K and 35% more harvestable yield than S J-2 when grown on soils with stratified K availability (Cassman et al, 1989b). Tolerance of late-season K deficiency by GC510 was associated with greater root development from peak bloom (mid-July) through boll fill (Brouder and Cassman, 1990 .4 Fig.…”

“…Pot systems for both solution culture and soil experiments were partitioned along the vertical axis to remove confounding effects due to the acropetal nature of root development and growth. Cultivars were 'Acala S J-2' (S J-2), which is sensitive to K deficiency, and the more K-efficient 'Acala GC510' (GC510) (Brouder and Cassman, 1990;Cassman et al, 1989b). Both SJ-2 and GC510 were evaluated in the solution culture studies, while only GC510 was used in the soil experiment.…”

“…Cotton cultivars differ in sensitivity to this late-season deficiency (Cassman et al, 1989b). Examination of spatial and temporal cotton root development in Kstratified profiles found greatest root extension rates at 0.1 to 0.2-m depth where K availability was high relative to subsoil (Brouder and Cassman, 1990).…”

Isolation, Characterization and Antibacterial Susceptibility test of Acinetobacter Species Obtained from Tertiary Care Hospital

“…Potassium is required in large amounts by cotton for normal crop growth and fiber development, with a typical high yielding crop containing about 200 kg K/ha soils not considered K deficient (Cassman et al, 1989). When soil K levels are insufficient, the cotton crop moves more quickly (earlier) from the vegetative to the reproductive phase (Gwathmey and Howard, 1998;Pettigrew, 1999) resulting in a decline in yield (Pettigrew, 2008).…”

Adubação foliar com nitrato de potássio em algodoeiro

“…Após o pico do florescimento, os sintomas de deficiência de K aparecem primeiro nas folhas maduras do terço superior da planta, e são similares aos sintomas que ocorrem antes do pico de florescimento (THOMPSON, 1999). À medida que a deficiência de K se torna mais severa, há redução na retenção dos frutos localizados nas últimas posições dos ramos (CASSMAN et al, 1989). A deficiência de K não impede a diferenciação e o aparecimento das estruturas, mas os botões florais não são retidos (ROSOLEM e BASTOS, 1997), além da queda prematura das folhas (SILVA, 1999).…”