Rootstock breeding in pomegranate (Punica granatum L.)
In commercial pomegranate production, an appropriate rootstock should improve orchard productivity, mitigate biotic and abiotic stresses, and help obtain high yield and fruit quality. During the last decade, pomegranate cultivation has increased substantially worldwide due to increasing consumers awareness of the fruits health benefits. Pomegranate trees are typically clonally propagated via rooted cuttings or tissue culture-derived plants on their roots for commercial production. There are several active pomegranate breeding programs focused on developing new fruit cultivars. In contrast, few rootstock breeding programs exist. Multiple breeding targets exist for pomegranate rootstock breeding. From the production perspective, precocious size controlling rootstocks could accelerate the establishment of high-density orchards and reduce production-related costs. Rootstocks with reduced suckering and compatibility with a broad spectrum of current commercial cultivars would also be highly desirable. Resistance to abiotic stresses such as waterlogging (root hypoxia), drought, and salinity (soil or water) will also expand the regions where pomegranate can be grown successfully. Resistance to biotic stresses such as root-knot nematodes and soil-borne pathogens such as Phytophthora would be highly desirable. Understanding the molecular and physiological mechanisms behind these important traits will enable researchers to advance in the breeding of pomegranate rootstocks and permit the deployment of marker-assisted selection (MAS) to shorten the development time of new rootstocks. Research into identifying and adopting superior rootstocks and strategies for extending outcomes to growers is needed. Current research and future needs will be presented and discussed in this review.
Sarkhosh, A. and Chaparro, J.X. (2022). Rootstock breeding in pomegranate (Punica granatum L.). Acta Hortic. 1349, 39-46
Phytophthora, root-knot nematodes, sucker habit, size controlling, waterlogging