Analysis of variability and phylogeny in pisum (Pisum spp.) using digital phenotyping and morphological traits

Abstract

Plant phenotyping links genomics with plant ecophysiology and agronomy. It is usually performed by non-destructive, automated and image-based technology and generates information for efficient and searchable digital characterization of crop that can be performed during routine, periodical regeneration of accessions in germplasm collections. In the present work, ninety-two accessions of Pisum from different species and subspecies were studied during 2015 and 2016. Size and colour traits were measured using digital images from a Samsung CLX 3300 scanner and analysed with appropriate software; also seed weight, plant height and days to flowering were measured. Highly significant differences between accessions and species and subspecies for all these traits were found. When distances among species and subspecies are calculated, P. sativum subsp. sativum showed the greatest distance with P. fulvum (8.02) followed by P. abyssinicum (7.13); while the smallest distance was found between P. fulvum and P. sativum subsp. transcaucasicum (3.16). A Neighbour-joining tree with a cofenetic r of 0.985 was obtained. Seed and pod characteristics as colour parameters and size, obtained by digital phenotyping, have proved to be suitable markers for genetic diversity evaluation and they are useful in evolutionary analysis, allowing the discrimination of the main wild and cultivated species in the genus Pisum.