Characterization and evaluation of rice genotypes under rainfed ecosystems in Malawi and Mozambique

Rice (Oryza sativa L.) is an important crop for human consumption world wide, including in under-developed countries in Africa, Asia and Latin America where it is cultivated in small holdings. In Mozambique and Malawi rice is produced by small scale farmers in many parts of the country and by large scale farmers in a few places where there is irrigation schemes. Despite its importance, there is limited information on trait characteristics and performance under different agro-ecological conditions including their potential when grown under rainfed ecosystems. The main objective of this research was to characterize and evaluate 20 rice genotypes under rainfed ecosystems in Mozambique and Malawi. The trials were carried out in a Randomized Complete Block Design (RCBD) during 2010-2011 with three replications and 20 treatments. Data on days to flowering, number of tillers, panicle length, number of grains per panicle, 1000-grain weight, grain size, milling yield percentage, leaf length, aroma, stickiness and grain yield were assessed and analysed. Additive Main effect and Multiplicative Interaction (AMMI) analysis indicated that the yield performances of genotypes were influenced by environmental effects (69.21%), 13.4% genotypic effects and 17.39% from genotypic-environmental interaction (GEI). Mozambique rainfed ecosystem produced the highest mean yield (2.48 t/ha) while the lowest mean yield performance was from Malawi rainfed ecosystem (1.38 t/ha). Nine traits, namely number of tillers, 1000- grain weight, panicle length, number of grains per panicle, grain length, grain shape, leaf length, days to 50% flowering and days to maturity were positively correlated with grain yield in two environments. Significant differences (P<0.001) were found in grain length, although 19 of the 20 genotypes could be considered to possess extra-long grain (>7.5 mm) showing that the farmers in both countries prefer long to extra-long grains. These results can be used by breeders in their crop improvement programs in order to incorporate the desirable traits and also to correct the undesirable traits in terms of farmers preferences.