Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: 3/16/2012
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Phosphorus (P) is a major limiting factor for cotton growth and development in many soil types. An experiment was conducted to study the influence of P nutrition on cotton growth and physiology under current and projected atmospheric carbon dioxide (CO2). Cotton plants were grown in six growth chambers with three levels of P-supply (0.2 (control), 0.05 and 0.01 mM) and two levels of CO2 (400 and 800 ppm) under optimum temperature and irrigation environment. The interaction between P nutrition and CO2 was not significant for many growth and physiological traits, indicating cotton response to P nutrition was similar under both levels of CO2. Irrespective of the CO2 levels, P deficiency significantly decreased plant height, node number, leaf area, photosynthetic rate and total plant biomass. In general, CO2 enrichment failed to alleviate the negative effect of P deficiency on cotton growth and development. The rate of stem elongation, leaf area expansion caused due to reduced cell elongation and lower carboxylation efficiency for photosynthesis were the major limiting factors for cotton growth under P deficiency. Cotton plants exhibited photosynthetic acclimation to projected atmospheric CO2 concentration. The results from this study clearly indicated that the available soil P will affect cotton growth and development independent of atmospheric CO2 concentration. The data obtained from the current study will be useful to develop numerical relationships of cotton tissue P content with growth and photosynthetic capacity. These relationships can be used to derive P response algorithms in cotton to improve the predictability of cotton crop simulation model GOSSYM.