Lactuca sativa mediated chitinase activity and resistance in pearl millet against Sclerospora graminicola

Abstract

Pearl millet seeds were treated with latex exts. (L1- 50 μl, L2- 100 μl and L3- 200 μl) of Asclepias curassavica, Calotropis gigantea, Croton sp., Eucalyptus alba, Morus alba, Nerium odoratum, Lactuca sativa and Tridax procumbens were applied on pearl millet seeds for 3 and 6 h to evaluate their role in growth promotion and downy mildew resistance. Latex exts. of all tested plants improved vegetative parameters when compared with the control. L. sativa (L2) at 3 h showed 38 and 18% increase in seed germination and vigor, resp., over the control. Plant height, shoot fresh and dry wt., no. of tillers and leaf surface area also increased upon latex treatment. Green house studies indicated that L. sativa required four days after challenge inoculation to build up max. resistance and offered 54% protection against downy mildew. Resistance induction was evident with increased activities of phenylalanine ammonia lyase (PAL) (four fold), peroxidase (POX) (three fold) and chitinase (three fold) in L. sativa (L2) treated seedlings challenged with the pathogen as compared to control seedlings. [on SciFinder(R)]