Comparing Canola, Field Pea, Dry Bean, and Durum Wheat Crops Grown in Saline Media

Abstract

Farmers have requested comparative information on the salt tolerance of the field crops they seek to grow as alternatives to wheat. In response, a study was conducted in the Salt Tolerance Testing Laboratory at Swift Current, SK, to compare the productivity of canola (Brassica napus cv. Cyclone), field pea (Pisum sativum cv. green‐seed Radley and cv. yellow‐seed Carneval), and pinto dry bean (Phaseolus vulgaris cv. Othello) crops to that of a durum wheat (Triticum turgidum cv. Kyle) crop grown in saline media. Test solutions were salinized prior to seeding by adding NaCl and CaCl2 (1:1 by mass) to hydroponic nutrients, resulting in three levels of root‐zone salinity: near zero, moderate, and severe [solution electrical conductivities of 1.2 (nutrients only), 11.2, and 24.9 dS m−1, respectively]. Eight response variables evaluated crop performance: time from seeding to initial emergence, emergence rate, final emergence and survival, plant height, aboveground biomass, grain yield, relative grain yield, and grain yield per plant. The durum wheat emerged and survived moderate and severe salinity better than any of the alternative crops. The wheat crop also produced more biomass and grain under moderately saline conditions than produced by the pea and the bean crops, but not the canola. Under severe salinity, neither the field peas nor the dry bean produced any grain, but the wheat and the canola crops managed to yield 0.4 and 20.1% of their respective productivity in nonsaline rooting media. The combined salt tolerance ranking in ascending order for the crop cultivars grown in both saline rooting media was: Othello = Carneval < Radley < Kyle < Cyclone.