Mechanistic Association of Quantitative Trait Locus with Malate Secretion in Lentil (Lens culinaris Medikus) Seedlings under Aluminium Stress

Abstract

Aluminium (Al) toxicity acts as a major delimiting factor in the productivity of many crops including lentil. To alleviate its effect, plants have evolved with Al exclusion and inclusion mechanisms. The former involves the exudation of organic acid to restrict the entry of Al3+ to the root cells while latter involves detoxification of entered Al3+ by organic acids. Al-induced secretion of organic acids from roots is a well-documented mechanism that chelates and neutralizes Al3+ toxicity. In this study, F6 recombinant inbred lines (RILs) derived from a cross between L-7903 (Al-resistant) and BM-4 (Al-sensitive) were phenotyped to assess variation in secretion levels of malate and was combined with genotypic data obtained from 10 Al-resistance linked simple sequence repeat (SSRs) markers. A major quantitative trait loci (QTL) was mapped for malate (qAlt_ma) secretion with a logarithm of odd (LOD) value of 7.7 and phenotypic variation of 60.2%.Validated SSRs associated with this major QTL will be useful in marker assisted selection programmes for improving Al resistance in lentil.

Natural variation of respiration-related traits in plants

“…The homolog of this gene was subsequently characterized in a GWAS study to be responsible for fruit malate content in tomato ( Tieman et al, 2017 ; Ye et al, 2017 ). Other studies on Al tolerance in lentil and common bean resulted in the identification of a major QTL for malate secretion and candidate gene including the Al-activated malate transporter and a multidrug and toxic compound extrusion gene in lentil and common bean, respectively ( Ambachew and Blair, 2021 ; Singh et al, 2021 ).…”

Physiological and proteomic characterization revealed the response mechanisms underlying aluminium tolerance in lentil (Lens culinaris Medikus)

“…Therefore, increasing our understanding to improving Al tolerance is required. Recent efforts have been made towards identifying candidate genes underlying the physiological and molecular mechanisms together with associated pathways for Al tolerance in lentil, which may provide insight into the adaptive Al stress responses (Singh et al, 2021a and 2021b). Yet, to our knowledge, no efforts have been made to explore the protein profiles of lentil under Al stress condition.…”

“…It is cultivated and consumed in different parts of the world, mainly in countries like Canada, India, Turkey, Iran, Ethiopia, Syria, Australia, China, Nepal, etc. (Singh et al, 2021b). Lentil growing areas worldwide are facing Al toxicity under acidic soil conditions.…”