Enhanced Tolerance to Ascochyta Blight in Chickpea Plants via Low Temperature Acclimation

• Published in: Russian journal of plant physiology 2020-07, Vol.67 (4), p.758-766
• Main Authors: Bahmani, M., Maali-Amiri, R., Javan-Nikkhah, M., Atghia, O., Rasolnia, A.
• Format: Article
• Language: English
• Subjects: Acclimation; Acclimatization; Ascochyta; Ascorbic acid; Biomedical and Life Sciences; Blight; Catalase; Chickpeas; Cultivation; Electrolyte leakage; Electrolytic cells; Genotype & phenotype; Genotypes; Hyphae; Infections; Inoculation; L-Ascorbate peroxidase; Legumes; Levels; Life Sciences; Low temperature; Malondialdehyde; Oxidative stress; Pathogens; Peroxidase; Photosynthesis; Plant Physiology; Plant Sciences; Pycnidia; Research Papers; Signs and symptoms; Superoxide dismutase; Temperature tolerance; Transcription
• ISSN: 1021-4437; 1608-3407
• DOI: 10.1134/S1021443720040020

Low temperature (LT) and Ascochyta blight are two major stresses in chickpea ( Cicer arietinum L.) cultivation. After exposure to LT treatments (acclimation, LT, acclimation + LT and control conditions), we evaluated induced responses by pathogen infection in LT-sensitive (ILC533) and -tolerant (Sel96Th11439) chickpea genotypes. In relation to genotype-specific defense reactions, tolerant plants responded more effective to the infection compared to sensitive plants, particularly after an acclimation treatment. LT treatments, and in particular an acclimation treatment, induced a significant decrease in disease symptoms 7 and 14 days after inoculation. Histopathological studies showed more infection throughout the cells of the sensitive genotype under control conditions. The minimal spread of the pathogen was observed in the tolerant genotype after acclimation treatment, and the infected plants did not contain pycnidia or hyphae of the pathogen. The electrolyte leakage index (ELI) and amount of malondialdehyde (MDA) after LT treatments were less than the values compared to post pathogen infection, indicating a difference in the degree of oxidative stress. Lower levels of pathogen-induced oxidative stress (ELI and MDA) and better photosynthetic efficiency (measured as F v / F m values) show that the tolerant genotype exposed to LT treatments acclimate better to the stress conditions compared to the sensitive genotype. Higher transcript levels for the superoxide dismutase , catalase and ascorbate peroxidase were detected during pathogen infection, particularly during the acclimation treatment, which might confirm lower oxidative stress in tolerant plants compared to sensitive plants. It is concluded that LT increased the capacity for tolerance to Ascochyta blight in chickpea plants and this was correlated with the stimulation of mechanisms involved in defense responses.