Effect of Integrated Soil Amendment Practices on Growth and Seed Tuber Yield of Potato (Solanum tuberosum L.) at Jimma Arjo, Western Ethiopia

Abstract

A field experiment was conducted to study the effect of integrated soil amendment practices on growth and seed tuber yield of potato at Jimma Arjo during the 2013 main cropping season.  Totally, there were sixteen different treatments consisting of different organic and inorganic fertilizers. The experiment was laid out in a randomized complete block design with three replications. The results showed that integrated use of organic and inorganic fertilizer had significant effect on plant height, leaf area index, and total fresh biomass and stem number per hill. Tuber yield and its attributing characters like total tuber number per hill, average tuber weight, large tuber medium and small tuber size number and weight, marketable and  unmarketable tuber number, marketable tuber yield, unmarketable tuber yield, total tuber yield and tuber dry matter were also significantly influenced. It was observed that integration of different organic and inorganic fertilizer had no significant effect on the days to maturity, harvest index and specific gravity. In general the application of wood ash, compost and farmyard manure alone or in combination in the absence of inorganic fertilizer did not prove much beneficial in promoting the growth, yield attributes and yield of potato. Application of 2 t/ha wood ash (WA) +5 t/ha farmyard manure (FYM) along with +111 kg N +92 kg P₂O₅/ha (RDF) resulted in the highest marketable tuber yield (12.74 t /ha) but was statistically in parity with RDF, however maximum total tuber yield was obtained with a combined application of 2 t/ha WA+5 t/ha compost (C) along with 100% RDF. The marketable and total tuber yield was positively and significantly correlated with growth components like plant height, total fresh biomass and stem number per hill. Similarly the marketable tuber yield was positively and significantly correlated with yield components like total tuber number per plant and marketable tuber number but negatively and significantly correlated with unmarketable tuber number.

Keywords: compost, farmyard manure, growth, soil amendment, wood ash, yield