Salicylic acid induces resistance to Alternaria blight in crop Brassica species
Altemaria blight, caused by Alternaria brassicae, is a major disease afflicting Brassica crops in India. Reduced bioefficacy and environment costs of recommended fungicides have spawned efforts to develop ecobenign management strategies. Induced resistance, through metabolic enhancement of plants owns defensive responses is one such option. In the present communication,results of experiment to manage altemaria by application of Salicylic add (SA), a known inducer of systemic acquired resistance pathway, are presented. The experiment comprised SA application @ 50 mg/l and 75 mg/l on two genotypes, B. napus cv. GSC 5 and B. juncea cv. ELM 079, before as well as after the onset of disease symptoms. SA @ 75 mg/l before disease onset proved better as evidenced by decreased disease severity on leaves; 29.7％ in B. napus cv. GSC-5 and 32.6％ in B. juncea cv. ELM 079 as compared to unsprayed control. The disease severity was also lower (24.8％ in B. napus and 30％ in B. juncea) when SA was sprayed after the onset of disease SA in both instances, provided better protection than recommended chemical fungicide (Biltox @ 250 og/l). Greater yield increase (8.4％ in B. napus and 9.5％ in B. juncea) was observed when SA was sprayed before the disease onset as compared to SA sprayed after disease onset (7.4％ and 7.6％ in B. napus and B. juncea respectively). In both instances the yield was higher than chemical control (4.2％ in B. napus and 4.4％ B. juncea) over the unsprayed control.Secondary metabolites like total phenols and O-hydroxy phenols showed increased level, three days after the SA application.Increase being higher when SA was sprayed before the onset of disease symptoms. The activities of defense related enzymes viz.,phenylalanine ammonia lyase, peroxidase and polyphenol oxidase also increased, three days after SA spray. Like the secondarymetabolites, enzyme activities also showed higher appreciation when SA was sprayed before the onset of disease. Changes in protein polymorphism, following SA application will be discussed.
Brassica Alternaria Blight Salicylic acid Biltox and induced resistance
M.K.Sangha A.K.Atwal P.S.Sandhu R.S.Bal S.S.Banga
Department of Plant Breeding, Genetics and Biotechnology Punjab Agricultural University, Ludhiana 141 004, India
国际会议
第十二届国际油菜大会( The 12th International Rapeseed Congress)
武汉
英文
1401-1403
2007-03-26（万方平台首次上网日期，不代表论文的发表时间）