Field Crop 2024, Vol.7, No.2, 79-92 http://cropscipublisher.com/index.php/fc 84 Improved Root Development: IAP promotes greater root length and density, which enhances the plant's ability to uptake nitrogen from the soil. This is particularly effective in high soil fertility conditions where increased root length correlates with higher nitrogen uptake and post-silking nitrogen accumulation (Zhao et al., 2019). Optimized Fertilizer Application: Split fertilizer application ensures that nitrogen is available to the plant at critical growth stages, reducing nitrogen losses through leaching and volatilization. This method has been shown to increase nitrogen recovery efficiency and agronomic nitrogen efficiency (Zhao et al., 2019; Wang et al., 2020). Enhanced Soil Fertility: The use of organic fertilizers such as farmyard manure and biochar improves soil structure and increases soil organic carbon content, which in turn enhances the soil's capacity to retain and supply nitrogen to the plants. This integrated approach has been shown to improve nutrient uptake and NUE in various cropping systems (Sailaza and Kannamreddy, 2019; Sarwar et al., 2023). Balanced Hormone Levels: IAP can regulate the balance of endogenous hormones such as indole-3-acetic acid (IAA), zeatin riboside (ZR), and gibberellin (GA3), which are crucial for grain filling and overall plant growth. Optimized hormone levels lead to improved grain-filling characteristics and higher grain yield, thereby enhancing NUE (Yu et al., 2020). Table 1 Effects of integrated agronomic practices management on grain flling parameters and yield of summer maize (2016–2017) (Adopted from Yu et al., 2020) Year Treatment Growth curve Parametric equation Correlation coeffcient Tmax (d) Wmax (g/100 kernels) Gmax (g/100 kernels d–1) P(d) Ro Graindry weight (g/100 kernels) Yield (Mgha–1) 2016 T1 y=29.81/(1+40.39e–0.15x) 0.9982 25.36 b 14.91 b 1.09 a 41.1 b 0.15 a 30.1 b 9.0 c T2 y=30.81/(1+35.53e–0.14x) 0.9902 25.85 b 15.40 a 1.06 a 43.4 a 0.14 b 31.3 a 10.8b T3 y=30.05/(1+41.46e–0.14x) 0.997 25.18 b 15.02 ab 1.03 a 43.8 a 0.14 b 30.3 b 13.5 a T4 y=31.02/(1+34.98e–0.14x) 0.9985 27.13 a 15.51 a 1.06 a 43.8 a 0.14 b 31.2 a 11.9b N0 y=25.16/(1+57.57e–0.15x) 0.9984 30.66 a 12.58 c 0.92b 41.1 b 0.15 a 27.2 d 9.8d N1 y=26.27/(1+50.54e–0.15x) 0.9981 26.81 b 13.14 b 0.96 b 41.0 b 0.15 a 29.2 b 12.2 c N2 y=32.47/(1+32.98e–0.14x) 0.9875 25.87 c 16.24 a 1.10 a 44.4 a 0.14 b 32.0 a 13.3 a N3 y=31.89/(1+47.37e–0.14x) 0.9975 26.94 b 15.94 a 1.14 a 41.9 b 0.14 b 30.9 b 12.9b 2017 T1 y=27.50/(1+59.02e–0.16x) 0.9983 29.09 a 13.75 d 1.09 a 37.9 d 0.16 a 31.3 c 9.0 c T2 y=30.04/(1+50.32e–0.14x) 0.9951 28.47 b 15.02 b 1.03 a 43.6 b 0.14 c 35.9 a 11.9b T3 y=28.93/(1+55.21e–0.15x) 0.9962 28.25 b 14.46 c 1.11 a 39.0 c 0.15 b 34.5 b 13.1 a T4 y=31.20/(1+46.84e–0.13x) 0.9935 29.18 a 15.60 a 1.03 a 45.5 a 0.13 d 35.5 a 12.4b N0 y=24.79/(1+56.89e–0.14x) 0.9895 28.91 a 12.40 d 0.87 c 42.9 b 0.14 a 31.2 c 9.2d N1 y=27.51/(1+56.97e–0.14x) 0.9977 28.88 a 13.76 c 0.96b 42.9 b 0.14 a 34.9 b 11.2 c N2 y=31.19/(1+48.74e–0.14x) 0.9957 28.64 a 15.59 a 1.06 a 44.2 a 0.14 a 35.8 a 12.7 a N3 y=30.17/(1+52.47e–0.14x) 0.9962 28.16 a 15.08 b 1.06 a 42.7 b 0.14 a 35.1 ab 12.2b Note: Tmax, days of maximum grain filling; Wmax, weight of maximum grain-filling rate; Gmax, maximum grain filling; P, active grain filling period; Ro, initiative value of grain filling. 2) T1, local smallhoder famers practices; T2, based on T1, increase planting density, decrease nitrogen rate, increase phosphorous and potassium rates, change fertilization time and delay harvesting; T3, based on T2, further increase planting density and greater increase fertilize rate to creating high yield; T4, based on T3, decrease planting density and the amount of fertilizer, were employed in a randomized block test design with four replications. N0-N3, 0, 129, 184.5, and 300 kg N ha–1, respectively.Values followed by different small letters within a column are significantly different at the 0.05 probability level (Adopted from Yu et al., 2020)
RkJQdWJsaXNoZXIy MjQ4ODY0NQ==