Abstract
Peanut (Arachis hypogaea) is the fifth most produced oil crop worldwide. Besides lack of water, fungal diseases are the most limiting factors for the crop. Several species of Arachis are resistant to certain pests and diseases. This study aimed to successfully cross the A-genome with B-K-A genome wild species previously selected for fungal disease resistance, but that are still untested. We also aimed to polyplodize the amphihaploid chromosomes; cross the synthetic amphidiploids and A. hypogaea to introgress disease resistance genes into the cultivated peanut; and analyze pollen viability and morphological descriptors for all progenies and their parents. We selected 12 A-genome accessions as male parents and three B-genome species, one K-genome species, and one A-genome species as female parents. Of the 26 distinct cross combinations, 13 different interspecific AB-genome and three AA-genome hybrids were obtained. These sterile hybrids were polyploidized and five combinations produced tetraploid flowers. Next, 16 combinations were crossed between A. hypogaea and the synthetic amphidiploids, resulting in 11 different hybrid combinations. Our results confirm that it is possible to introgress resistance genes from wild species into the peanut using artificial hybridization, and that more species than previously reported can be used, thus enhancing the genetic variability in peanut genetic improvement programs.
Highlights
Peanut (Arachis hypogaea L.) is the fifth most produced oil crop worldwide and is an important food crop (USDA, 2013a)
Species of the genus Arachis have been intensively studied, and several wild species are more resistant to diseases compared to A. hypogaea (Stalker and Moss, 1987; Fávero et al, 2009)
We found that the structures are largest in the hybrids from crosses between A. hypogaea and the amphidiploids, followed by the A. hypogaea accessions, and the synthetic amphidiploids
Summary
Peanut (Arachis hypogaea L.) is the fifth most produced oil crop worldwide and is an important food crop (USDA, 2013a). Species of section Arachis that lack this small chromosome pair are more heterogeneous, comprising a group with 2n = 18 chromosomes (Lavia, 1998; Peñaloza and Valls, 2005), another with six subtelocentric chromosome pairs (Fernández and Krapovickas, 1994), and a third group with 20 metacentric or submetacentric chromosomes. This third group includes A. ipaënsis (Fernández and Krapovickas, 1994), the most probable donor of the peanut B-genome, and other species with distinct degrees of affinity to A. magna, A. gregoryi, and A. valida (Robledo and Seijo, 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
