Effect of different doses of jasmonic acid against cotton leaf curl disease: Induced protein and latent carry over

Response of different american cotton accessions namely RS 921, LH 2076, PIL 8, ankur 3028 BGII and a desi cotton variety LD 694 to Jasmonic acid (JA) in the induction of proteins for protection against cotton leaf curl disease (CLCud) was studied. At four to six leaf stage, potted plants were sprayed with different concentration of JA i.e. 50 μM, 100 μM, 150 μM and 200 μM. Plants showed highest protein induction at 150 μM in all the treated cultivars w.r.t their control. SDS-PAGE revealed induction of proteins (15–45 kDa) in treated samples w.r.t their controls. JA @ 150 μM resulted in lower CLCud incidence as well as disease index w.r.t control. Latent carryover detection of symptomless plants treated with 150 μM of JA through PCR amplification using DNA β specific primers confirmed the presence of virus in all the tested cotton accessions except LD 694 which depicted that induced proteins did not eliminate virus but might be playing a role in suppressing the proliferation of virus or might have kept virus in inactive state. JA application thus, resulted in imparting tolerance with the induction of PR proteins but did not lead to complete resistance against the disease.