Germination characteristics of Sorghum bicolor (L.) Moench. under different pH regimes after chemo-priming

Abstract

AbstractSoil pH not only plays a regulatory role in seed germination but also influences seedling development, flowering, and crop yield. The study investigated the germination characteristics of sorghum [Sorghum bicolor (L.) Moench.] under varying pH to understand the potential ameliorative effects of seed priming using plant growth-promoting substances. Seeds were sown in Petri dishes with pH moistened solutions at 1, 3, 5, 7, 9, 11, and 13 respectively. These were replicated five times in the second stage, viable seeds were first primed in 150 ppm indole-3-acetic acid, gibberellic acid, and vitamin C before sowing in pH solutions. The experiment showed no significant changes in morphology or physiology of primed and unprimed seeds and no germination at extreme pH. However, there was a significant difference in the activity of enzymes, germination time, and speed as well as germination percentages of both primed and unprimed seeds. Although chemo-priming did not reverse the effect of pH, it was observed however that vitamin C had a significant effect on germination percentage at higher pH. Germination was observed to be impaired at extreme pH. Seeds did not respond to germination capacity suggesting an optimal pH range of 3 and 11 for germination without priming. However, priming did not show any improved germinability index. Seeds primed in the presence of light showed enhanced germination at pH 7. Generally, the germination index without priming showed better germination characteristics than primed seeds, which suggests pH interactions with primers may be a limiting factor.