S. S. Aujla

Integrated management of wheat Karnal bunt

Abstract Management of Karnal bunt by cultural practices, chemical sprays and by breeding disease resistant varieties is described. The practices of polythene mulching and wheat straw burning after mechanical harvesting raised the soil temperature considerably. Polyethylene mulching enhanced the soil surface temperature to 54.5°C and straw burning raised the temperature of the soil surface, 5 cm and 10 cm depth of soil to 92.5°C, 67.0°C and 58.0°C respectively and were found to be lethal to the bunt spores enabling the soil to be disinfested from the bunt propagules. Tilt (propioconazole), Agrozim and Bavistin (carbendazim) and Bayleton (triadimefon) were effective fungicides against Karnal bunt. Some lines of wheat and allied genera (Aegilops) were found to be resistant to the bunt and this resistance can be manipulated for transferring into bread wheat.

Studies on multilines in wheat (Triticum aestivum L.).12. Breeding of a multiline variety by convergence of breeding lines

SummaryThe variation among the component lines of the KSML 3 (a multiline based on cultivar Kalyansona, spring bread wheat) was studied for agronomic characteristics. For days to earing and plant height the variation was small. This helped in imparting uniformity to the multiline. The lines had an improved tillering ability and had larger seeds. This partially explained the increased yield potential of the multiline as compared with Kalyansona.All the lines were susceptible only to one or two races of the yellow and brown rust. In no case any race was virulent against all the lines. In the field all the lines were resistant to both rusts.