Physiological and molecular aspects of pod shattering resistance in crops

Abstract

Pod shattering resistance is a trait acquired by crops in the process of evolution. Manipulation of physiological and molecular processes is fundamental for the improvement of shattering resistance in crops. In this review we discuss several enzymes, key hormones and their possible roles or relationships involved in pod shattering, and highlight responsible genes, quantitative traits loci (QTLs) and their implications for increased pod shattering resistance. Cell wall degrading enzymes, particularly β-glucanases and endopolygalacturonases play an important role in the process of pod dehiscence. It is not clear how and to what extent a specific hormone regulates the dehiscence zone differentiation and the dehiscence process is not clear. Resistance to shattering is highly heritable and is not controlled by a single gene. Several QTLs associated to dehiscence have been identified in crops, while the underlying genetic functions of these QTLs deserve further investigation. Further physiological analyses of the pod wall will help to understand better the pod dehiscence.