CRISPR/Cas: A modern fruit breeding tool
A strategic modern improvement tool is vital for eliminating obstacles of conventional crop breeding in fruit crops. One such remarkable advanced tool is CRISPR/Cas targeted mutagenesis. Because of easiness, economical, target specific and alternative to transgenic, CRISPR/Cas technology is preferred over other gene editing tools. In fruits, citrus was the first crop edited with CRISPR. To date, CRISPR-SpCas9 derived from Streptococcus pyogenes has been widely used to modify a targeted trait at specific site in citrus, grape, banana, apple, pear, strawberry and kiwi for proof of efficient editing, functional genomics study, early flowering, plant architecture modification, enhanced nutritional quantity, fruit quality improvement and pathogen resistance. Despite the various positive attributes, one of the major limitations with Cas9 endonuclease system is causing off target effect in edited plants. Recently, CRISPR-Cas12a ‘class II/type V CRISPR nuclease’ from Prevotella and Francisella bacteria has been employed as an alternative system for genome editing with fewer off-targets than Cas9. Moreover, their efficiency is demonstrated in citrus for Canker resistant. Hence, this review deals with how CRISPR/Cas system of gene editing as a modern breeding tool can go a long way in accelerating the future crop improvement in fruit crops.
CRISPR-SpCas9, CRISPR/Cpf1, Disease resistant, Multiplex genome editing, Nutritional enhancement.