The Effects of Combined Application of Cattle manure And Mineral Nitrogen And Phosphorus Fertilizer on Growth, Biomass Yield, And Quality of Potato ( Solanum Tuberosum L) Tuber Inabelo Area at Masha District sheka Zone, South-Western Ethiopia

Soil fertility decline is considered as one of the major causes for resulting in reduced yield of potato production in abelo area Masha district sheka zone of south-western Ethiopia. Hence, a field experiment was conducted in Belgand Mehre season, in abelo area, Masha district south-western Ethiopia, to investigate the effect of combined use of application of Cattle Manure (CM)) with mineral NP on growth, biomass yield, quality, of potato tuber. The treatments comprised combinations of three rates (2.5,5, 7.5t ha -1) of CM with 25%, 50% and 75% of recommended rates of mineral NP, respectively. In addition, 100% recommended rate of mineral NP for the experimental site (165 kg N ha -1 and 137 kg P 2O 5 ha -1) and zero rates were used for comparison. The experiment was laid out in a randomized complete block design with three replications. The results revealed that applying 7.5 t ha -1 CM combined with 75% mineral NP gave significantly days to 50% flowering by 7 days i.e. From 56-6 and 14 days i.e. from 51-65, days to 50% maturity by 5 days i.e. from (101 -106) and 13 days from (95 -108) and increases plant height from 56-69 and 63-78, Increase shoot fresh weight by 39.66% from (1274.59- 1780.2 ghill -1) and 36.66% from (1213.91 -1658.99 ghill -1) and shoot dry weight by 46.8% from (40.4 ghill -1 to 59.333 ghill -1) and 41.66% from (40 to 56.667 ghill -1),increased dry matter content from (21.085-25.782) and (22.36 to 24.47), specific gravity from (1.083- 1.107) and (1.092 -1.101) reduces small tuber size percentage Form (27.306 to 17.069) and (43.946 -14.267) and improves medium size tubers from (65.56 to 74.79) and (44.58 80.26) in Belg and Mehre season as compared to zero application. Respectively. Therefore, it can be concluded that, the use of combined application of CM (7.5 t ha -1) together with 75% of recommended rates of mineral NP (123.75kg N ha -1 and 103.05kg P2O5 ha -1) can significantly increases growth, biomass yield, improvement in tuber quality. Keywords: Biomass Yield; Cattle Manure; Nitrogen; Phosphorous; Tuber Qualit