Assessment of Allelopathic Properties of Sorghum in Integration with Varying Rates of Seeding for Suppression of Weeds and Maize Yield Enhancement

Abstract

Weeds are uninvited plants that interfere with farming practices and degrade the quality of crops yield. Weeds are competing with cultivated crops plants for essential resources such as moisture, nutrients, sunlight, space, and carbon dioxide. Their rapid initial growth, especially in open fields, gives them a competitive edge. This study investigated the ability of sorghum extracts from both immature and mature plants to influence the growth of other organisms at varying seeding rates for their impact on weed count (m^-2) and the yield of the maize variety Dadu Maize-I. This study comprised multiple weed management strategies, including a control (no weeding), utilization of sorghum plant extracts at 15 Litters per ha (both immature and mature) alone, and in combination with a reduced herbicide dose at 1 Litters per ha, along with manual weeding twice. These treatments were applied under different maize seeding rates (20, 25, 30, & 35 kg per ha). Statistical analysis revealed that different weeds controlling strategies significantly reduced weed infestation, thereby enhancing kernel yield. The most effective treatment was the application of immature sorghum extract at 15 Litters per hectare combined along decline herbicide rate (1 Litters per ha), which significantly lowered weed count (m^-2), and increased weed mortality (%), ultimately improving maize growth and kernel yield (kg per ha). The second-best treatment was mature sorghum extract at 15 Litters per ha with a herbicide dose of 1.0 Litters per ha, where weeds were effectively suppressed and kernel yield was enhanced. Regarding seed rates, the lowest weed count (m^-2) and highest kernel yield (kg per ha) were recorded at 35 kg ha⁻¹; however, the optimal kernel yield (kg per ha) was achieved at 30 kg per ha. These findings suggest that integrating sorghum plant extracts with a decline herbicide dose is an effective weed management approach, and a maize seed rate of 30 kg per ha is ideal for maximizing kernel yield.