Field Evaluation of Pearl Millet for Chinch Bug (Heteroptera: Blissidae) Resistance

Abstract

The chinch bug, Blissus leucopterus leucopterus (Say) (Heteroptera: Blissidae), is the most important insect pest of pearl millet (Pennisetum glaucum L. R. Br.) production in the southeastern and central United States. Chinch bug feeding causes stunting and leaf sheath necrosis of the young seedlings and loss of crop stand in severe infestations. Sixteen germplasm entries (including hybrids and inbreds) of pearl millet were screened for chinch bug resistance on 2 planting dates. ‘Dove’ proso millet (Panicum miliaceum L.) was interplanted in 2-row strips among experimental plots to attract adult chinch bugs and establish initial chinch bug infestations. Use of a proso millet trap crop strip was effective in establishing chinch bug infestations for screening of pearl millet for chinch bug resistance in the field. Weekly samplings were begun when plants were at the 5-leaf stage. Significant differences in adult and nymph numbers, stunting and necrosis ratings, percent tiller loss, crop stand loss, and chlorophyll content were recorded for the 16 pearl millet germplasm entries. Combining all injury evaluation parameters (i.e., stunting and necrosis ratings, percent tiller loss, and crop stand loss), we identified that ‘TifGrain 102’ had a moderate level of chinch bug resistances e data demonstrated that, millet would aeh resistance. Entries 637 (i.e., 59668A × NM-5B), 639 (59668M × 9Rm/4Rm), 648 (i.e., 02GH973 × Tift 454), and 653 (i.e., NM-5A1 × NM-7R1R5) were the most resistant; whereas, entries 640 (i.e., Tift 99B), 641 (i.e., Tift 454), and 644 (i.e., 02F 289-1) were the most susceptible to chinch bug feeding. The study showed the combination of nondestructive visual ratings (i.e., stunting and necrosis ratings, tiller loss, and stand loss) and chlorophyll content could be used for evaluating chinch bug resistance in pearl millet.