Induction of systemic resistance to bacterial blight caused byXanthomonas campestrispv.malvacearumin cotton by leaf extract from a medicinal plant zimmu (Allium sativumL. × Allium cepaL.)

Abstract

Induction of systemic resistance to bacterial blight caused by Xanthomonas campestris pv. malvacearum in cotton by leaf extract from a medicinal plant zimmu (Allium sativum L. 6 Allium cepa L.) Abstract Aqueous extract (10%) from leaves of zimmu (Allium sativum L. 6 Allium cepa L.) when applied as foliar spray to first and second leaves of cotton plants induced systemic resistance in third and fourth leaves to a challenge infection with Xanthomonas campestris pv. malvacearum and reduced the number of lesions by up to 73% compared with water-treated control plants. The treated leaves exhibited significantly high activity of enzymes phenylalanine ammonia-lyase, peroxidase and polyphenol oxidase along with rapid accumulation of phenolics. The activities of chitinase and b-1,3-glucanase were greatly elevated in treated plants as compared to water-treated controls. An 11-fold increase in chitinase activity was evident 4 d after treatment. Western blot analysis revealed that a chitinase with an apparent molecular weight of 58 kDa that cross-reacted with a barley chitinase antiserum was induced in cotton leaves 3 d after treatment and the maximum induction of this chitinase was detected 4 d after treatment. The present study provides evidence for the induction of biochemical defence mechanisms in cotton leaves after treatment with leaf extract from zimmu.

Defense responses in tomato landrace and wild genotypes to early blight pathogenAlternaria solaniinfection and accumulation of pathogenesis-related proteins

“…The resistant genotypes (LE996 and Seijima Jeisei) showed maximum PAL activity when compared to susceptible ones under challenge inoculation. These results are well correlated with the findings of Geetha et al (2005) and Satya et al (2006).…”

Potential of ethyl acetate fractions of Stryphnodendron adstringens shells and fruit extracts of Caesalpinia ferrea to control bacterial leaf speck and on the potentiation of defense enzymes in tomato

“…Cotton plants treated with the leaf extract of zimmu (Allium sativum L. × Allium cepa L.) showed higher activities of PAL, POX and PPO and high concentrations of phenolic compounds that contributed to an increase in resistance against X. campestris pv. malvacearum infection (Satya et al, 2007).…”

“…The plant extracts that contain many of these metabolites have been investigated for their increased resistance against pathogens infection, such as the zimmu extract (Allium sativum L. x Allium cepa L.) in the control of Xanthomonas campestris pv. malvacearum on cotton (Satya et al, 2007) and Lasiodiplodia theobromae and Colletotrichum musae on banana (Sangeetha et al, 2013 ). Extracts of Datura metel increased rice resistance against Rhizoctonia solani and X. oryzae pv.…”

Induction of resistance in chickpea (Cicer arietinum L.) against Ascochyta rabiei by applying chemicals and plant extracts

“…oryzae in rice has been investigated (Kagale et al, 2004) and it was found that foliar application of leaf extract effectively reduced the incidence of sheath blight and bacterial blight of rice. Satya et al (2007) applied aqueous leaf extract of zimmu (Allium sativum L. x Allium cepa L.) to first and second leaves cotton plants that induced systemic resistance in third and fourth leaves and reduced the number of lesions by up to 73% after challenged infection with Xanthomonas campestris pv. malvacearum compared with water-treated control plants.…”