Resistance to thrips (Enneothrips flavens) in wild and amphidiploid Arachis species

Abstract

Thrips (Enneothrips flavens) is a pest that causes severe damage and yield losses to peanut crop if not properly controlled. The main control method currently used by farmers is bi-weekly application of insecticides during crop development, which, in addition to its toxicity, is very costly. Thus, new sources of resistance must be identified in order to reduce the use of insecticides and effectively manage the pest. This study aimed to evaluate the occurrence and symptoms of E. flavens infestations in 12 accessions of 10 wild species of Arachis and nine amphidiploids, as well as to compare their morphoagronomic characteristics to those of commercial cultivars. To this end, we conducted experiments during two summer seasons, using a randomized block design with four replications. We conducted evaluations of the severity of infestation, noting visual symptoms of E. flavens and morphological and reproductive characteristics of the Arachis plants. Results indicated that wild accessions V 7635 (A. vallsii), V 13250 (A. kempff-mercadoi), K 9484 (A. batizocoi), Wi 1118 (A. williamsii), V 14167 (A. duranensis) and V 13751 (A. magna) are the most promising for obtaining useful new amphidiploids. Among the amphidiploids, An 12 (A. batizocoi x A. kempff-mercadoi)4x, An 9 (A. gregoryi x A. stenosperma) 4x, and An 8 (A. magna x A. cardenasii)4x showed high level of resistance to E. flavens. The identified thrips resistant wild and amphidiploid Arachis species may be used in future breeding program to produce thrips resistant peanut cultivars.

Evidences that polyploidization and hybridization affected resveratrol content in Arachis interspecific hybrids

“…The effect of polyploidization and hybrization on different traits in Arachis interspecific synthetic allotetraploids have been studied (Burow et al, 2001;Fávero et al, 2009Fávero et al, , 2015Leal-Bertioli et al, 2012, 2017Michelotto et al, 2015Michelotto et al, , 2016Michelotto et al, , 2017. The characterization of resveratrol content in Arachis allotetraploids could add new value to these genotypes, which have been developed to be used in peanut pre-breeding programs (Bertioli et al, 2011).…”

Identification of Smut Resistance in Wild Arachis Species and Its Introgression into Peanut Elite Lines

“…Loos) D.K. Bell & Sobers] (Tallury et al, 2014), nematodes (Simpson and Starr, 2001; Simpson et al, 2003), and several insect pests (Stalker and Lynch, 2002; Stalker et al, 2002; Michelotto et al, 2017). Therefore, the use of wild Arachis as a source of resistance to peanut smut is a promising option.…”

Groundnut (Arachis hypogaeaL.) improvement in sub-Saharan Africa: a review

“…ICGV 91114, ICGS 76, ICGV 91278, JL 24, and DH 86) using two synthetic resistance sources namely: ISATGR 278-18 and ISATGR 5B (Kumari et al 2014). Resistance to thrips was introgressed into cultivated groundnut cultivars using amphidiploid species such as A. batizocoi x A. kempffmercadoi, A. gregoryi x A. stenosperma, and A. magna x A. cardenasii (Michelotto et al 2017). Introgression of root-rot nematode resistance gene (Rma) into tetraploid groundnut from synthetic allotetraploid donor (TxAG6) has been widely practiced in modern cultivars (Nagy et al 2010).…”