Abstract
Effects of leaf rust (Puccinia recondita Rob. ex Desm. f.sp.triticina Eriks.) infection of spring wheat (Triticum aestivum L.) plants ‘Kolibri’ on transpiration rate and leaf-water potential were studied during growth in a climate chamber at various soil-water potentials. The water potentials ranged from −210 J.kg−1 to −1025 J.kg−1. Rust infection has been found to increase the transpiration rate. The magnitude and duration of the increase depended on soil-water potential and the time (growth stage) of inoculation. The transpiration rate of uninfected heads was affected by rust infection of the leaves, also depending on soil-water potential and infection time. Overall resistance of the plants to water flow was determined; sudden changes in resistance due to rust infection concur with high crop losses due to abortion of kernels. Leaf-water potentials were calculated and found to vary in uninfected plants from −1740 J.kg−1 at the lowest soil-water potential to −580 J.kg−1 when water was plentiful. At high soil-water potential, the leaf-water potential of rusted plants was lower than that of uninfected plants, but this was not so at low soil-water potentials. The effects of leaf-water potential on rust growth and water flow through leaves and heads are discussed. Suggestions about the application of the results to breeding for tolerance (= resistance to loss) and, eventually, to prevention of loss by rust in semi-arid areas are given.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have