Journal of Experimental Sciences 2020, 11: 35-40 doi: 10.25081/jes.2020.v11.6256 https://updatepublishing.com/journal/index.php/jes J Exp Sci • 2020 • Vol 11 35 INTRODUCTION Cassava (Manihot esculenta Crantz) is a key staple food crop in Uganda, ranking second to bananas in terms of area occupied, total production and per capita consumption [1, 2, and 3]. Since its introduction in the early 1860’s, cassava continues to play a significant role in the diet of Ugandans. The crop contributes a considerable proportion of the calorie intake with its per capita consumption estimated at 132 kg per person per year [4]. About 75% of farmers grow cassava for home consumption and about 25% grow it for cash and other uses. Cassava is responsible for increased food security in most parts of Uganda. The crop is used on its own or as an additive to either millet or sorghum flour to make local bread. This is typical in the millet-cotton farming areas covering west Nile, north, east and north-eastern parts of Uganda. In the banana-coffee farming areas covering south and south-western parts of Uganda, cassava is mainly cultivated for fresh storage root consumption [5]. The crop is usually intercropped with legumes and cereals on small plots of land. The average yield of cassava in Uganda is estimated at 14.6 tons per hectare while the annual production is estimated at 11.3 million tons, which accounts for about 3.4% of Africa’s total cassava production and 1.9% of total cassava production worldwide [5]. Due to the increasing demand for cassava as a basic food and source of income for smallholder farmers, as well as its future potential as an industrial crop, research interventions involving farmers are urgently needed to improve cassava production and productivity. The effectiveness of a plant breeding programmes depends on the ability of a breeder to select superior individuals or families as defined by the breeding objective. Breeders are generally interested in improving more than one trait at a time, or improving one trait without affecting the performance of others. In a multistage selection scheme, breeders begin with creation of genetic diversity by crossing elite clones which are selected based on their performance; this process is carried on through different stages and often ends with a few clones in the regional trials (RT) that have survived the selection process. In the RT, greater emphasis is put on yield and/or other critical farmer-preferred traits. This process takes about six to seven years or more starting from the initial crosses which is too long especially when the demand for new varieties is urgent. Comparing the efciency of base and multiplicative selection indices for yield and quality traits in Cassava Severin Ntivuguruzwa 1,2 *, R. Edema 1 , P. Gibson 1 , M.E.B. Alladassi 1 , A. Nduwumuremyi 2 , W.Abincha 1,4 , R. Kawuki 3 1 Department of Agricultural production, College of Agricultural and Environmental Sciences, Makerere University, P.O Box 7062, 2 Rwanda Agricultural and Animal Resources Board, P. O Box 5016, Rubona, Huye, Rwanda, 3 National Crop Resources Research Institute, P.O Box 7084, Kampala, Uganda, 4 Mount Kenya University, P.O Box 4441, Kisii, Kenya, Kampala, Uganda ABSTRACT The efficiency of two selection indices; base index and multiplicative index was compared to determine the effectiveness of each in identifying superior genotypes in cassava (Manihot esculent Crantz) population. Genotypic data on various yield and quality traits among 570 cassava genotypes were used to construct these selection indices. The efficiency of these indices was compared by determining the performance means of each genotype for studied traits and computing selection differentials of each index. Best linear unbiased predictions (BLUPs) for dry matter content and harvest index were also used for comparison of the two selection indices. Base index produced high performance means of all five studied traits and proved to be more efficient compared to multiplicative index in improvement of cassava genotypes. In addition, base index produced high selection differentials for three out of five studied traits. It was concluded that base index is useful in cassava germplasm selection. KEYWORDS: Selection index, efficiency, cassava, base index, multiplicative index Copyright: © The authors. This article is open access and licensed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted, use, distribution and reproduction in any medium, or format for any purpose, even commercially provided the work is properly cited. Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. Received: May 23, 2020 Accepted: September 20, 2020 Published: October 07, 2020 *Corresponding Author: Severin Ntivuguruzwa Email: ntiseverin@yahoo.fr ISSN: 2218-1768 Research Article