Abstract:Resources are limited, thus improving resource use efficiency is a key objective for cereal-based cropping systems. This field study was carried out to quantify resource use efficiencies in selected C 3 and C 4 cereals under split nitrogen (N) application regimes. The study included the following treatments: six cereals (three C 3 : wheat, oat, and barley; and three C 4 : maize, millet, and sorghum) and four split N application regimes (NS 1 = full amount of N at sowing; NS 2 = half N at sowing + half N at first irrigation; NS 3 = Results revealed that C 4 cereals out-yielded C 3 cereals in terms of biomass production, grain yield, and resource use efficiencies (i.e., radiation use efficiency (RUE) and nitrogen use efficiency (NUE)), while splitting N into three applications proved to be a better strategy for all of the selected winter and summer cereals. The results suggest that C 4 cereals should be added into existing cereal-based cropping systems and N application done in three installments to boost productivity and higher resource use efficiency to ensure food security for the burgeoning population.

Increasing resource-use efficiency is of prime importance in sustainable agriculture. A field study was carried out to improve nitrogen-use efficiency (NUE) and radiation-use efficiency (RUE) of three C 4 summer cereals, i.e. maize, millet, and sorghum, under an irrigated arid environment. The results showed that among various cultivars of cereals, cultivars Pearl (maize), 18 BY (millet), and Jumbo (sorghum) produced the highest aboveground total dry matters and grain yields. The highest NUE and RUE were obtained by splitting the nitrogen dose 3 times, i.e. at sowing and at first and second irrigation. The NUE for maize, millet, and sorghum varied from 30.97 to 32.97, 21.34 to 23.32, and 17.39 to 20.22 kg kg -1 , respectively. RUE ranged from 1.14 to 1.47, 0.85 to 1.08, and 0.91 to 1.13 g MJ -1 for maize, millet, and sorghum crops, respectively. Maximum resource-use efficiency was achieved by 3 splits, while the minimum was obtained in the control group. It is inferred from this study that those varieties of C 4 summer cereals may be commercially grown that are more efficient in utilizing the available resources for harnessing greater NUE as well as RUE under an irrigated arid environment.