Predicting potential sugarcane crosses through molecular markers and kinship coefficient

• Grant number: 17/05357-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2017
• End date: December 31, 2017
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Rodrigo Gazaffi
• Grantee: Rachel Cruz Carvalho Tairum
• Host Institution: Centro de Ciências Agrárias (CCA). Universidade Federal de São Carlos (UFSCAR). Araras , SP, Brazil

Abstract

Sugarcane breeding plays a key role in the Brazilian sugarcane industry providing cultivars with high productivity, disease resistance and adapted to several environmental conditions. In general, the process of obtaining new cultivars are characterized in two main stages: the generation of a segregating population through full-sib crosses between different parents, followed by several sub-stages of selection and cloning. Several criteria can be used for parental selection, but progeny test based on combination ability is probably the most suitable one. This implies several issues due time-consuming and costs to evaluate all the crosses. On the other hand, molecular markers allows us to infer the similarity and/or genetic distances between genotypes. In theory, the variability of a given cross is proportional to its genetic distance so, if the crossing presents a high mean, the chance of finding new cultivars is increased. However, few studies have related the average performance of crosses or families, with genetic distance and/or even kinship coefficient, calculated through genealogy. In this way, the present work aims to analyze three mapping populations, planted in the years 2011, 2012 and 2013, in randomized blocks design, with four replications, evaluating sugar content (POL), fiber, tons of stalks and sugar per hectare (TSH and TPH , respectively). Genetic distance will be estimated using Jaccard, Simple Matching and Dice coefficients, as well as the Malécot coefficient for kinship. We will correlate the results from field trials and genetic estimates in order to verify if any of these measures would be used as an indicator for predicting sugarcane crosses.