Evaluation of Cool- and Warm-Season Grasses for Resistance to Multiple Chinch Bug (Hemiptera: Blissidae) Species

Chinch bugs are common pests of many agronomic and horticulturally important crops and turfgrasses. The extensive overlap of plant hosts and geographic distribution of Blissus leucopterus leucopterus (Say), Blissus leucopterus hirtus Montandon, Blissus insularis Barber, and Blissus occiduus Barber underscores the importance of identifying resistant germplasm. Cool- and warm-season turfgrasses and sorghum, Sorghum bicolor (L.) Moench, were evaluated for resistance to chinch bugs in the Blissus complex, and the presence of multiple resistance was documented. Greenhouse studies established that B. occiduus-resistant ('Prestige', formerly NE91-118) and -susceptible ('378') buffalograsses,, Buchloë dactyloides (Nuttall) Engelmann, were susceptible to all other chinch bug species. KS94 sorghum exhibited resistance to both B. occiduus and B. l. leucopterus, whereas B. insularis-resistant St. Augustinegrass, Stenotaphrum secundatum (Walter) Kuntze ('Floratam'), was also resistant to B. occiduus. B. l. leucopterus-susceptible sorghum ('Wheatland') and B. insularis-susceptible St. Augustinegrasses ('Raleigh' and 'Amerishade') were highly resistant to B. occiduus. Endophyte-free and -enhanced fine fescues (Festuca spp.) were moderately to highly susceptible to B. l. hirtus but moderately to highly resistant to B. occiduus. The results of this research showed the buffalograsses evaluated, including B. occiduus-resistant Prestige, are moderately to highly susceptible to the three other chinch bug species. In contrast, B. occiduus did not cause considerable damage to any of the turfgrasses or sorghum cultivars evaluated, other than buffalograss, irrespective of whether or not they are resistant to another chinch bug species. This information is increasingly important as various grasses become adapted to regions that may possess chinch bug species other than those with which they are typically associated. These levels of Blissus resistance should be included when selecting resistant germplasm for managing Blissus species pests.