
%0 Journal Article
%A Lu, Zhenmin 
%A Chen, Jiwei 
%A Percy, RG 
%A Sharifi, MR 
%A Rundel, PW 
%A Zeiger, E 
%T Genetic Variation in Carbon Isotope Discrimination and Its Relation to Stomatal Conductance in Pima Cotton (<I>Gossypium barbadense</I>)
%J Functional Plant Biology
%D 1996/04/01
%V 23
%N 2
%P 127-132
%K 
%R https://doi.org/10.1071/PP9960127
%U https://www.publish.csiro.au/paper/PP9960127 
%X Stable carbon isotope discrimination (&#916;) was evaluated in primitive and cultivated Gossypium barbadense L. Significant differences among cultivated Pima lines were positively associated with the degree of selection for lint yield and heat resistance. A population mean study of a cross between B368, a primitive, uncultivated G. barbadense, and Pima S-6, an advanced line, showed that &#916; is probably under genetic control, and could be a suitable selection trait in breeding programs. Eleven uncultivated accessions of primitive G. barbadense of varying origins grown in one environment showed a broad range of &#916; values (18.8-20.50), pointing to substantial genetic variation of &#916; in the G. barbadense germplasm. A was strongly correlated with stomatal conductance (gs) in the commercial lines, a segregating F2 population of the B368 &#215; Pima S-6 cross, and the collection of uncultivated G. barbadense. This relationship indicates that variation in gs is the main source of variation for &#916; in both uncultivated and commercial G. barbadense. The positive correlation between &#916;, gs and yield in the commercial Pima lines provides further evidence for selection pressures on higher gs ensuing from selection for higher yield and heat resistance. Selection for higher &#916; could increase yield in crops grown in hot, high irradiance, and well-irrigated environments. 
