Tendai P Chibarabada1 and Gaylord T Murahwa2
1Agronomy Department, Zimbabwe Sugar Association Experiment Station, P. Bag 7006, Chiredzi, Zimbabwe
2Midlands State University, Private Bag 9055, Gweru, Zimbabwe
Biostimulants enhance nutrition efficiency, abiotic stress tolerance, and crop quality. The study evaluated biostimulants under saline-sodic conditions to improve yields and help plants tolerate stress. Two saline-sodic study sites in Zimbabwe with pH ranging from 7.14 – 8.34, and sodium adsorption ratio (SAR) ranging from 8 – 15.1 were selected. Varying rates of biostimulants (Cosmocel® product mix and Soilex®) were applied as a foliar spray and soil drench, respectively as per supplier recommendations. Data collected included periodic leaf gas exchange measurements [stomatal conductance (gs), assimilation (A)], growth parameters (tillers and plant height) and yield and ERC% at maturity. Biostimulants improved A and gs by 18-40% relative to the control at one site that had highest SAR. Soilex® significantly increased plant height and plant population at both sites (P<0.05). Despite positive results of A, gs, height and tiller counts, yield was not significantly improved. ERC% was significantly improved (12.98% – 13.66%) by Cosmocel® tank mix (P>0.05). The study is ongoing and will evaluate biostimulants over several crop cycles and different environments. Effects on soil quality parameters over time will also be evaluated.