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Fusarium oxysporumf. sp ciceris, the causal organism of chickpea vascular wilt disease reduces yield up to 90% annually. Xylem plays a prominent role during Fusarium wilt. In resistant hosts, vascular wilt pathogens are presumably recognized by both extra and intracellular plant receptors that elicit defense responses in the xylem vessels. However, in susceptible hosts, fungus colonized in the xylem causing vessel clogging leading to wilting of the plant. In this study, we have described an efficient method to obtain RNA of high quality in sufficient amount from LCM-derived chickpea root xylem tissue. This includes sample preparation by tissue fixation, OCT embedding, cryo-sectioning, dissecting the target cells, and finally capturing them using infrared rays. RNA was extracted from these captured xylem cells, quantified using bioanalyzer to yield quantity ranging from 92–114 ng µl-1with RIN value up to 7. These RNA samples would be utilized for molecular studies like in our case transcriptome analysis to find out genes involved in wilt resistance in chickpea. We were able to successfully isolate RNA using the above procedure from fungus-infected chickpea root samples of susceptible, resistant, and control plants. Histological observation indicating the infestation of Foc2 in the vicinity of xylem tissue of root was done.

The Ascochyta Blight (AB) caused by Ascochyta rabieiis recognized as a major foliar disease of chickpea worldwide. The rapid detection of AB is a prerequisite for the effective and timely management of disease at an early stage to prevent the AB epidemics in chickpea. The Indian isolates of A. rabieiwere characterized pathogenically and sequencing of Internal Transcribed Spacer (ITS) region. The phylogenetic analysis of ITS sequences indicated 99.97% similarity index and isolates formed two major clusters through neighbour joining analysis. The RAPD monomorphic bands were cloned and sequenced. The best set of SCAR marker pairs designated as SCAR1F/SCAR1R were validated using PCR with sensitivity of 0.30 ng of genomic DNA. The RAPD derived SCAR marker demonstrated high sensitivity and were species specific in the detection of A. rabiei. The SCAR marker could be used for quick and timely detection of the A. rabieifungus in seed materials of quarantine importance for phytosanitary certification of chickpea.