Establishment of standards of Diagnosis and Recommendation Integrated System (DRIS) of pineapple culture (Ananas comosus (L.) Merr) Sugar loaf variety in subequatorial zone of Benin

The Diagnosis and Recommendation Integrated System (DRIS) provides a means of simultaneously identifying imbalances, deficiencies and excesses in crop nutrients, and ranking them in order of importance. Some proponents of DRIS claim it able to establish nutrient standards regardless of varietal or geographic variables or both. This study concerns the use of DRIS approach to assess pineapple (Ananas comosus (L.) Merr)  nutrient requirements of the variety Perola on ferrallitic soils in the Allada District, located in the coastal hinterland of Benin. The aim of this study is to: (1) evaluate pineapple nutrient status in the Commune of Allada; (2) compare the DRIS method with the critical value method (CVM) for foliar nutrients diagnosis of "Perola" variety; (3) develop DRIS norms for "Perola" pineapple variety; (4) evaluate the current fertilization practices on the nutritional status for that variety. To achieve this goal, sixty (60) plots of 16m² (4m х 4m) have been established in 60 farmers’ pineapple fields, at the rate of 15 per districts. In each field a representative plot of 16 m2 (4 m х 4 m) was established and 10 "D" leaves samples were taken at flowering stage in each plot. DRIS standards for pineapple were developed from 60 observations of nutrient composition. DRIS and CVM methods were able to correctly diagnose N, S and Mg for variety "Perola". However, Critical Value Method failed to make a correct diagnosis for P, K, Ca, and Zn for the pineapple variety "Perola". When DRIS revealed excess for Zn and deficiencies for K and Ca in variety "Perola", CVM indicated respectively adequation of Zn, K and Ca. As conclusion, superior precision is obtained with DRIS approach compared to CVM.

Source de publication: Annales de l’Université de Parakou, Série Sciences Naturelles et Agronomie 2010, 1: 51-69

Contacts du ou des auteurs: AGBANGBA Cossi Emile, DAGBENONBAKIN D. Gustave et KINDOMIHOU Valentin (vkindomihou@yahoo.fr)