Abstract:
A study was undertaken to assess the soil nutrients status on selected maize growing areas and determine combinations of nutrients to optimize yield. Soil samples were collected from10 villages where maize is the main food and cash crop. These areas were; Kipera, Lolanguru, Itema, Nyangahe, Farmnyamwezi, Malolo, Mpenge, Mawiti, Lyaudusi and Msange. Two composite samples were made from each village resulting to 20 samples. Field experiment was conducted at two villages (Kipera and Nyangahe) to determine combinations of nutrients for optimal maize yield. Factor (a) – main plot was three maize varieties (Staha, TMV1 and Situka M1) and factor (b) – subplots comprised six nutrients treatments namely; an absolute control (T1), nitrogen alone at 100 kg N ha-1 (T2), nitrogen at 100 kg N ha-1 and phosphorus at 40 kg P ha-1 (T3), nitrogen at 100 kg N ha-1, phosphorus at 40 kg P ha-1 and 100 kg K ha-1 (T4), nitrogen at 100 kg N ha-1, phosphorus at 40 kg P ha-1, 100 kg K ha-1 and 20 kg S ha-1 (T5) and nitrogen at 100 kg N ha-1, phosphorus at 40 kg P ha-1, 100 kg K ha-1 and 20 kg S ha-1 and 10 kg Zn ha-1(T6), were tested in split plot design in randomized complete block arrangement, replicated three times. Results obtained from Kipera and Nyangahe villages, showed that fertilizer types applied and their combination (T6) produced significantly (P<0.05) higher maize grain yield over T1, T2 and T3. Also Staha and TMVI showed better results than Situka M1 at both sites. Overall the study results indicated that the fertilizer combination in (T6) at 100 kg N ha-1, at 40 kg P ha-1, 100 kg K ha-1 and 20 kg S ha-1 and 10 kg Zn ha-1 could be the best strategy in improving maize grain yield.
