Mwadalu, RizikiMochoge, BensonMwangi, MainaMaitra, SagarGitari, Harun2022-06-032022-06-032022-03Mwadalu, Riziki & Mochoge, Benson & Mwangi, Maina & Maitra, Sagar & Gitari, Harun. (2022). Response of Gadam Sorghum (Sorghum bicolor) to Farmyard Manure and Inorganic Fertilizer Application. 15. 51–60.DOI: 10.30954/0974-1712.01.2022.6http://ir-library.ku.ac.ke/handle/123456789/23786Article in International Journal of Agriculture, Environment and Biotechnology : IJAEB: 15(01): 51-60, March 2022 DOI: 10.30954/0974-1712.01.2022.6This study aimed to evaluate the effect of Farm Yard Manure (FYM), mineral fertilizers (nitrogen and phosphorus), and their combination on the production of Gadam sorghum in a Kenya Semi-arid region of Makueni and Machakos counties. The first experiment evaluated the response of sorghum to N and P application at four levels (0, 25, 50, 75 kg ha-1) whereas the second evaluated the response of sorghum to the combined application of FYM (0, 5, and 10 tons ha-1) and N and P fertilizer (0 and 50 kg ha-1). Nitrogen application enhanced sorghum yields more than phosphorus addition. Combining N at 75 kg ha-1 and P at 50 kg ha-1 gave the highest sorghum grain yield in Kampi ya Mawe which was 135% higher than the control. In Katumani, combining 50 kg ha-1 N and 25 kg ha-1 P gave the highest mean grain yield, which was 68.3% more than the untreated control. In the follow-up experiment (Kampi ya Mawe), combining FYM with NP fertilizer (50 kg ha-1 N & P and 10 t ha-1 FYM) gave the highest yield; 13.7% more than the control. At Katumani, however, combining FYM at 10 t ha-1 and 50 kg of N and P resulted in insignificant differences in grain yield compared to the untreated control. Nitrogen use efficiency (NUE) was optimal at 50 kg ha-1 N and declined at 75 kg N ha-1. Similarly, phosphorus use efficiency (PUE) was highest at 50 kg P ha-1. Based on the results, it’s evident that the integration of organic and inorganic nutrient sources enhances sorghum yield. HIGHLIGHTS m Nitrogen application enhanced sorghum yields more than phosphorus addition. m Sorghum grain yield increased by 135% after combining N at 75 kg ha-1 and P at 50 kg ha-1 at Kampi ya Mawe. m Nitrogen and phosphorus use efficiency was optimal at 50 kg ha-1 application rate. m Integration of organic and inorganic nutrient sources enhanced sorghum grain yield.enASALssoil fertilitysorghumnutrient use efficiencyArticle