Evaluation of Soil Fertility and Performance of Maize(Zea Mays L.)in Small Holders Maize Farms in Namtumbo District, Ruvuma Region.

Maize yield in Namtumbo district is low and ranges from 1-2 t/ha in most small holders farms as compared to 7-10 t/ha reported in other parts of Tanzania. The yield is below the crop potential productivity due to low use or not using fertilizers completely. The objectives of the study were to evaluate the fertility status of soils and to determine the response of maize to nutrients. Composite soil samples were collected from 20 farms in 20 villages and used for assessment of soil fertility status. Field experiments were conducted during 2012/2013 season at Namabengo and Lusewa villages in Namtumbo District, to study the effects of six treatments, namely (i) control (ii) N80 P0 K0 Zn0, (iii) N80 P40 K0 Zn0 (iv) N80 P40 K80 Zn0, (v) N80 P40 K80 +Zn10 and (vi) N120 P40K80 Zn10. Split plot design was used where the main plots factor was maize varieties and sub plots factor was nutrient combinations. Major findings of this experiment were that the major soil fertility constrains for maize production were N, P, K and Zn. The fertilizer combination of N120 P40K80 Zn10 was the best combination for all varieties in both sites which increased grain yield from 0.5 t ha-1 in the control treatment to 8.91t ha-1 at Namabengo site and from 3.07 t ha-1 in control - 7.53 t ha-1 at Lusewa site with the use of improved variety (DKC 8053). However, for farmers to obtain high grain production they must use good agronomic practices which include the use of improved seed, the recommended fertilizer rates (N120 P40K80 Zn10), planting at right time and weeding twice