Comparative adaptation of canola ( Brassica napus) and Indian mustard ( B. juncea) to soil water deficits: yield and yield components

Abstract

Four experiments were conducted comparing yield and yield components of canola and Indian mustard at different levels of soil water deficit. At least three genotypes of each species were used in the field experiments and all were matched for phasic development. Mustard produced more dry matter than canola (between 9 and 120%) with the biggest increases occurring at the greatest soil water deficit. Mustard yielded more than twice as much seed as canola under these conditions while there were no yield differences at low deficits. Components of yield differed between the two species with mustard having more pods plant −1 but fewer seeds pod −1. Oil and protein concentrations of seed responded to drought in a similar manner in both species. The mechanisms by which yield components varied between the two species are discussed in relation to breeding for higher yields under conditions of water deficit.