Effect of silicon on Melanaphis sorghi (Theobald, 1904) (Hemiptera: Aphididae) infesting grain sorghum ( Sorghum bicolor )

Melanaphis sorghi, a global pest, severely reduces sorghum yields. This study examined silicon (Si) effects on grain sorghum and M. sorghi biology. Two hybrids, AG1090 and BRS373, received varying precipitated silicic acid doses (0, 2, 4, and 6 tons ha⁻¹). M. sorghi pre-reproductive and reproductive periods, fecundity, longevity, and nymph survival were assessed under controlled conditions. Greenhouse-grown plants underwent phytometric analyses, and aphid damage was visually scored. Chemical composition, including NIRS and tissue analysis, was performed. The 6 tons ha⁻¹ dose with BRS373 was most effective, reducing nymph survival (68% to 38%) and fecundity (51 to 31 nymphs/female). PCA showed no correlation between plant Si concentration and damage. This highlights Si supplementation’s potential to mitigate M. sorghi in sorghum.