Effects of Seed Coating Agents on Some Agronomic Properties and Rhizobacterial Population of Vigna unguiculata

Abstract

The agricultural activities had tremendously benefitted from the application of pesticides. However, various objectionable practices among farmers had exposed the soils, plant and its community of organisms to different level of toxicity. Therefore, this study evaluated the effects of seed coating agents on germination rate, shoot length, leave numbers and population of rhizobial and phosphate solubilizing bacteria (PSB) of beans plant (Vigna unguiculata). The mesocosm experiment was carried out in a greenhouse using a randomized block design with five replicates over the period of 5 weeks. The seed coating agents used were Imidadoprid-Thiram powder formulations and black powdery waste from dry-cell batteries. The seed coating agents were applied at the recommended rate value of 1.25 g/kg and at the rate that double the concentration of recommended field rate (2.50 g/kg). The application of Imidadoprid-Thiram at recommended rate and spent battery waste at the same rate did not have any significant effect (p > 0.05) on the germination of V. unguiculata as compared to the control. However, significant reductions (p < 0.05) in germination were observed in the seed coated with both coating agents at the rate above the recommendation value. Likewise, no significant effect (p > 0.05) of seed coating agents was observed on the average number of leaves of growing V. unguiculata seedling but significant reductions (p < 0.05) were observed in the shoot length of all the treated seedling as compared with control. Both Imidadoprid-Thiram and spent battery wastes were observed to have a significant negative (p < 0.05) effect on the average numbers of both rhizobia and PSB counts in the rhizosphere region of V. unguiculata, with effects more pronounced in higher doses.