Yield and Quality of Alfalfa as Influenced by Additions of S to P and K Fertilizations under Greenhouse Conditions
- Source:
- Agronomy journal 1977 v.69 no.4 pp. 531-535
- ISSN:
- 0002-1962
- Subject:
- Haplorthods, Humaquepts, Medicago sativa, NPK fertilizers, alfalfa, clay, dry matter accumulation, fertilizer application, greenhouse production, greenhouses, potassium fertilizers, rain, sandy loam soils, sandy soils, silty clay soils, sulfur, sulfur fertilizers, superphosphate, Quebec
- Abstract:
- Alfalfa (Medicago sativa L.) obtains sulfur from soil reserve, air, and rainfall. These sources of S may need to be supplemented with fertilizer S in normal superphosphate to produce optimum yields. The objective of this work was to determine the need of alfalfa in S fertilization in relation with the addition of P and K normally used on Quebec soils. Alfalfa ‘Rambler’ was grown in the greenhouse and supplied with P, K, and S. A total of 18 treatments and 3 replicates were used on two types of soils — a Humaquept (silty clay Kamouraska) and a Haplorthod (sandy-loam St. André). Dry matter yields and uptake of N, P, K and S by the crop were significantly increased by the addition of S. The increases were more important on the silty clay than on the sandy loam soil. Responses of alfalfa to S were greater than to the addition of P and K. Critical concentrations of S in the crop were found to be 0.10% on the sandy loam and 0.12% on the silty clay soil and appear to be as good an index as N:S ratios to determine S deficiency in alfalfa. Results of this study showed the importance of S fertilization to improve the output of alfalfa on both clay and sandy soils. They suggest that the growing use of concentrated fertilizers containing little S can lead eventually to deficiencies in the plants if other sources of S are not added to normal P and K fertilization.
- Agid:
- 2523736
- https://doi.org/10.2134/agronj1977.00021962006900040002x