Identification of Fungus Resistant Wild Accessions and Interspecific Hybrids of the Genus Arachis

Abstract

Peanut, Arachis hypogaea L., is a protein-rich species consumed worldwide. A key improvement to peanut culture involves the development of cultivars that resist fungal diseases such as rust, leaf spot and scab. Over three years, we evaluated fungal resistance under field conditions of 43 wild accessions and three interspecific hybrids of the genus Arachis, as well as six A. hypogaea genotypes. In the first year, we evaluated resistance to early and late leaf spot, rust and scab. In the second and third years, we evaluated the 18 wild species with the best resistance scores and control cultivar IAC Caiapó for resistance to leaf spot and rust. All wild accessions displayed greater resistance than A. hypogaea but differed in their degree of resistance, even within the same species. We found accessions with as good as or better resistance than A. cardenasii, including: A. stenosperma (V15076 and Sv 3712), A. kuhlmannii (V 6413), A. kempff-mercadoi (V 13250), A. hoehnei (KG 30006), and A. helodes (V 6325). Amphidiploids and hybrids of A. hypogaea behaved similarly to wild species. An additional four accessions deserve further evaluation: A. magna (V 13751 and KG 30097) and A. gregoryi (V 14767 and V 14957). Although they did not display as strong resistance as the accessions cited above, they belong to the B genome type that is crucial to resistance gene introgression and pyramidization in A. hypogaea.

<b>Resistance to <i>Enneothrips flavens</i> Moulton and genetic parameters estimation in interspecific genotypes of peanut

“…These progenies are of great value because they indicate potential in crossings following the breeding. In addition, the best phenotypic values coincided with the highest predicted values (BLUP) for all traits in the two generations (Tables 3 to 6), corroborating the results obtained by Michelotto et al (2015). BLUP is a function of phenotypic values that have the common objective of predicting true genetic values, and it has been used as a selection tool in various crops (Baldissera et al, 2012;Pinheiro et al, 2013;Regitano Neto, Ramos Júnior, Gallo, Freitas, & Azzini, 2013).…”

“…BLUP is a function of phenotypic values that have the common objective of predicting true genetic values, and it has been used as a selection tool in various crops (Baldissera et al, 2012;Pinheiro et al, 2013;Regitano Neto, Ramos Júnior, Gallo, Freitas, & Azzini, 2013). In peanut crop, BLUP has been used to assist the selection of lines at the early stages of breeding programs (Luz, Santos, Silva Filho, & Mello Filho, 2010) and has helped to identify sources of resistance to aerial fungal diseases and in interspecific accessions and hybrids of the genus Arachis L. (Michelotto et al, 2015).…”

“…Pre-breeding research on crossings of A. hypogaea L. with wild germplasm has been conducted in Brazil with the aim of identifying sources of resistance to major pests and foliar diseases (Fávero, Simpson, Valls, & Vello, 2006;Fávero, Moraes, Garcia, Valls, & Vello, 2009;Janini, Boiça Júnior, Godoy, Michelotto, & Fávero, 2010;Michelotto et al, 2015;Santos et al, 2011;Santos, Godoy, Michelotto, & Fávero, 2013). One of the crosses made involved an elite cultivar from the Instituto Agronômico de Campinas (IAC 503) and the amphidiploid (A. magna x A. cardenasii) 4x .…”

Research Article Coupled transcript and metabolite identification: insights on induction and synthesis of resveratrol in peanut, wild relatives and synthetic allotetraploid.

“…Data showed that accessions of A. ipaënsis and A. duranensis have higher concentrations of resveratrol than the two allotetraploids, which is a surprising result since many other studies showed differences between diploids and polyploids, the latter having better characteristics than the former (Fávero et al, 2009;Xu et al, 2014;Michelotto et al, 2015;Leal-Bertioli et al, 2015, 2017. The lack of polyploidy superiority has been previously observed for Arabidopsis thaliana and Pyrus communis, in which only a few metabolites differ between diploids and synthetic autotetraploids.…”

Organography of greenhouse and field accessions of wild Arachisspecies (section Arachis)

“…Annual and perennial species in the section Arachis, which is considered the best adapted section, have great genetic potential for breeding with cultivated peanut (Simpson and Starr, 2001;Fávero et al 2006;Michelotto et al 2015;Fávero et al 2015b).…”