Buffalograss (Buchloe dactyloides) resistance to the Rhodesgrass mealybug.

Buffalograsses, Buchloë dactyloides (Nutt.) Engelm., were evaluated under greenhouse culture for resistance to the Rhodesgrass mealybug, Antoninis graminis Maskel.  Among 76 entries, four genotypes, TTU-58B, TTU-86A, TTU-94A and TTU-223A, had mean infestations ≤ 0.22 mealybugs per 6.4 cm diam plant.  TTU-86A and  TTU-94A are tetraploids while TTU-58B and TTU-223A are hexaploids.  An additional five hexaploid genotypes were infested with ≤ 1 mealybug per plant.  However, FH-5, a diploid, had a moderate infestation rate but exhibited the lowest damage ratting of 1.78 (scale of 1 to 5, where 1 = little or no damage) among all the test entries.  Two genotypes, TTU-35 and TTU-115 were the most susceptible entries with the highest infestation rate of > 21 Rhodesgrass mealybugs per plant; these entries were also hexaploids.  Several other diploid and tetraploid genotypes were also evaluated, but did not provide resistance.