Spinach: better management of downy mildew and white rust through genomics

Abstract

Spinach (Spinacia oleracea) has become an increasingly important vegetable crop in many parts of the world. Significant changes in production practices, particularly in the U.S. and E.U., have occurred in the past 10-15 years as a result of increased product demand. These changes likely increased the incidence and severity of downy mildew, caused by Peronospora farinosa f. sp. spinaciae. Recently, progress has been made to define the genetics of resistance to this pathogen and the closely related white rust pathogen, Albugo occidentalis. In this paper, we outline the genetic and genomic resources currently available for spinach, draw parallels between spinach diseases and more thoroughly characterized pathosystems, and describe efforts currently underway to develop new genetic and genomic tools to better understand downy mildew and white rust of spinach. Presently, many crucial tools and resources required to define the molecular underpinnings of disease are unavailable for either spinach or its pathogens. New resources and information for spinach genomics would provide a jumpstart for ongoing efforts to define (and deploy) genetic resistance against downy mildew and white rust.

Genetic map construction and QTL analysis of nitrogen use efficiency in spinach (Spinacia oleracea L.)

“…Spinach is a dioecious species with separate male and female plants and occasional monoecious plants (Correll et al 2011). Spinach is diploid with 2n = 12 chromosomes and has a genome size of 989 Mb (Arumuganathan and Earle 1991).…”

SNP association analysis of resistance to Verticillium wilt (Verticillium dahliae Kleb.) in spinach

“…Spinach (Spinacia oleracea L.) is an economically important vegetable crop worldwide (Morelock and Correll, 2008;Correll et al, 2011). In addition to its economic importance, spinach is one of the faster growing vegetable crops in the US and other regions in terms of per capita consumption and is considered one of the healthiest vegetables in the human diet due to its high concentration of nutrients and healthpromoting compounds (Dicoteau, 2000;Morelock and Correll, 2008).…”

Development of a breeding strategy for nitrogen use efficiency in spinach (Spinacia oleracea L.)

“…For this, a high-density genetic map and mapping populations segregating for disease resistance are important (Correll et al 2011). …”

“…Another important development is the sequencing and assembly of the spinach genome, which may be available shortly (UC Davis 2016). The availability of an assembled spinach genome sequence will further facilitate marker development, QTL analysis and candidate gene discovery, as well as discovery of favourable alleles, and will together with the tools presented in this thesis pave the way for marker assisted selection (MAS) for traits like NUE to become an integrated part of spinach breeding programs (Correll et al 2011). …”

“…Spinach is a dioecious species with separate male and female plants and occasional monoecious plants (Correll et al 2011).…”