Abstract:

To enhance the efficacy of simultaneous planting of millet seeds and fertilizers, a study was conducted to identify the most suitable fertilizer types for this model. The study evaluated the impacts of four types of fertilizers, including urea-formaldehyde slow-release compound fertilizer (N), coated controlled-release mixed fertilizer (B), seaweed membrane controlled-release mixed fertilizer (H), and ordinary compound fertilizer (CK), on millet growth, yield, and soil nutrient levels. The results showed that during the early growth stage, the root dry weight of millet under the N treatment was significantly lower than that of the other three treatments. However, from heading to maturity, both root and stem-leaf dry weights gradually increased across all treatments. Throughout the entire growth period, the root and ear dry weights under the CK treatment were the lowest. At maturity, the soil NO₃^--N content under the N treatment was the lowest, being 36.6% lower than that of the CK treatment. The NH₄⁺-N, available potassium, and effective phosphorus contents under the N treatment were also the lowest during the flowering stage, with reductions of 75.77%, 10%, and 62.15%, respectively, compared to the B treatment. In terms of yield, fertilizer B outperformed H, CK, and N, with yields from the B and H treatments being 6.82% and 5.45% higher, respectively, compared to CK. RDA and Mantel analyses identified several key factors that promoted yield improvement, including NH₄⁺-N and effective phosphorus content during flowering, as well as NH₄⁺-N and pH levels in various soil layers at maturity. The differences in soil nutrient levels caused by the different fertilizers were important factors affecting millet yield. In the later stages of growth, the plants were primarily supplied with nitrogen and phosphorus, and the pH of the surface soil emerged as a key factor influencing yield. Under the mechanized seeding and fertilization model, fertilizer B had a more positive effect on millet growth and yield compared to fertilizers N and CK.

Key words: simultaneous planting of seeds and fertilizers, millet, new type of fertilizer, soil nutrient, yield