Search Results       Your search for [author]Sonza, Petra Umahag. returned 1 record.           Correlation of soil test values of phosphorus and potassoium with responses of rice to fertilizer application. by Sonza, Petra Umahag.; 1981. Subject: Rice -- Fertilizers and manures; Soils -- Phosphorus content; Soils -- Potassium content; Soils -- Testing.          Add to Book Cart Relevance: 33.42%