Genotyping-by-sequencing technology reveals directions for coconut (Cocos nucifera L.) breeding strategies for water production

The dwarf coconut is widely used in the coconut hybrids production (tall × dwarf) because it presents higher precocity and higher productivity of the number of fruits in relation to the other varieties. However, these hybrids originated from Intervarietal crossing, produce fruits with low market acceptance for water quality. Intravarietal crosses (dwarf × dwarf) could act as an alternative, but little is known about the diversity within and between the dwarf sub-varieties, which can lead to a misdirection to breeding programs. In this study, we report the level of genetic variability between dwarf coconut accessions belonging to three sub-varieties (green, yellow and red), as well as the analysis of population structure. We used the RAD-sequencing methodology for analyzing 39 genotypes belonging to dwarf coconut populations collected in different producing regions of Brazil. Our results show that the SNP markers increased the power of detection of genetic variability, facilitating the decision making regarding future crosses in order to explore the heterosis in dwarf coconut breeding programs. Inter-sub-varietal crosses of dwarf coconut are highly promising to reduce the time and optimize the process of obtaining new cultivars for water production requiring field assessments to confirm its agronomic potential.