Phenotyping Techniques and Identification of Soybean Resistance to the Kudzu Bug

Abstract

The kudzu bug (KZB), Megacopta punctatissima Montandon 1896, is a newly invasive Asian pest of soybean [Glycine max (L.) Merrill] in the southeastern United States. Due to the unique biology of this soybean pest, six screening techniques were tested to identify host plant resistance (HPR) to KZB. Soybean lines previously characterized as resistant to either leaf‐chewing or piercing–sucking insects were used to test screening techniques and to identify potential sources of KZB resistance. Four open field experiments and one field cage experiment were conducted in 2010 to 2013 to screen ‘Benning’ near‐isogenic lines (NILs) for KZB resistance. These NILs possess different combinations of quantitative trait loci (QTLs) for resistance to leaf‐chewing insects from PI 229358 (QTLs M, G, and H) and PI 227687 (QTL E); however, none of these lines were consistently effective at controlling KZB. Additionally, 30 plant introductions (PIs) with previously observed resistance to either the soybean aphid (Aphis glycines Matsumura) or the silverleaf whitefly (Bemisia tabaci Gennadius) were screened in the field for KZB resistance. Six lines were identified as potential sources of resistance to KZB from this field using a KZB index. A no‐choice (antibiosis) assay was developed to confirm resistance observations from the field and to characterize the type of host plant resistance. PI 567336A and PI 567598B were confirmed as the most resistant of the screened PIs, and were characterized as having antibiosis resistance to KZB.