FULL-LENGTH RESEARCH ARTICLE Genetic Control of Inheritance of Fruit Quality Attributes in Tomato (Solanum lycopersicum) Jiregna Tasisa 1 • Wassu Mohammed 1 • Shimelis Hussien 2 • Vasantha Kumar 1 Received: 21 September 2017 / Accepted: 27 February 2018 Ó NAAS (National Academy of Agricultural Sciences) 2018 Abstract The experiment comprised of seven tomato inbred lines (two processing and five fresh market) and 21 F 1 hybrids produced by crossing of them in a 7 9 7 half diallel fashion excluding the reciprocals. The study was conducted at the Haramaya University, Ethiopia during July 2015 to June 2016 to analyze the genetics of inheritance of some physical and chemical quality traits. A randomized complete block design with three replications was used to conduct the exper- iment. Among the studied characters, only shape index and titratable acidity fulfilled the additive–dominance hypothesis. Therefore, non-allelic gene interaction could be involved in the inheritance of the characters which did not fit the model. The parental line Roma VF contained mostly recessive genes with increasing effects for shape index, and the parental lines Marglobe and Eshete contained mostly recessive genes with the increasing effects for titratable acidity. Therefore, employing these lines in hybridization for shape index and titratable acidity improvement could be ineffective, since the rapid increased frequency of recessive alleles which is the cause of loss of vigor could be resulted in advancing generation. Keywords Tomato Á Quality traits Á Gene action Á Diallel Á Additive–dominance Introduction Tomato (Solanum lycopersicum L.) is one of the most consumed vegetable crops in the world. It belongs to Solanaceae family. It is a diploid and autogamous and has chromosome number of 2n =2 9 = 24 [6]. Tomato is a rich source of micronutrients for human diet [3]. It is an excellent source of many nutrients and secondary metabolites such as potassium, vitamins C and E, b-car- otene and lycopene that are important for human health [25]. In Ethiopia, tomato is one of the most popular and widely grown vegetable crops. It is produced by small farmers and commercial growers for both fresh fruit and for processing industries [7]. It is an important cash-gen- erating crop for small farmers and also provides employ- ment for production and processing industries. Fruit quality attributes [flavor, antioxidant, TSS (°Bx) content, etc.] have become a major focus of most traditional and inno- vative tomato breeding approaches [17]. The effort is to improve the genetic makeup of both fresh market and processing tomato varieties. Nowadays, fruit quality traits such as fruit acidity, total soluble solids content and antioxidants become a major focus of tomato breeding approaches due to their increas- ing importance in processing industries. The demand is met by developing varieties having improved processing qual- ity through genetic manipulation of the crop. In order to design appropriate breeding strategy for particular crop, it is important to have the information on the genetic control for a particular trait of the crop. The diallel method proposed by Hayman [8], Hayman [9], Jinks & Jiregna Tasisa djiregnat@yahoo.com 1 School of Plant Sciences, Haramaya University College of Agriculture and Environmental Sciences, P.O. Box 138, Dire Dawa, Ethiopia 2 African Centre for Crop Improvement, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa 123 Agric Res https://doi.org/10.1007/s40003-018-0314-x