Callose accumulation in roots of soybean seedlings under water deficit

Abstract

Callose is cell wall constitutive component of some plant tissues and it is synthesized and deposited in response to stresses (abiotic and biotic). Considering physiological seed quality as an attribute that determines the rapid and uniform emergence of seedlings under a wide range of environmental conditions, this study verified the callose accumulation in seedling roots of soybean cultivars showing contrasting seed vigor under water deficit. Six soybean cultivars were used and the physiological seed quality was determined by germination and vigor tests. Water deficit simulation was performed by germination tests with polyethylene glycol solution at − 0.4 MPa, and the control (0.0 MPa; deionized water). 24 h after radicle protrusion, three samples of 13 root tips were prepared for callose determination. The cultivar ‘BMX Potencia RR’ presented lower germination (87%) when compared to the other cultivars. Vigor results allowed the separation of cultivars into two vigor categories, high and low. The callose concentration deposited on soybean root tissues ranged from 0.0511 to 0.1244 μg per root tip. This allowed the observation of the contrast in callose accumulation between the cultivars during the water deficit, and this is responsive to the greater susceptibility of low vigor cultivars to stress in order to isolate plant tissue through the deposition of a physical barrier. Callose accumulation can be used as indicative of susceptibility to water stress in soybean cultivars.