Selecting resistance to Bipolaris sorokiniana and Fusarium graminearum in intermediate wheatgrass

Forage yield and persistence of intermediate wheatgrass and pubescent inter mediate wheatgrass can be adversely affected by foot rot caused by Fusarium graminearum, Bipolaris sorokiniana, or both Putative B. sorokiniana- and F . graminearum-resistant plants were selected from both Reliant and Manska c ultivars of intermediate wheatgrass to produce four populations. When plant s from half-sib families that were selected for resistance were intercrosse d and progeny subjected to subsequent selection cycles for B. sorokiniana a nd F: graminearum resistance, progressively higher percentages of putative resistant seedlings were found for three of the four selected populations c ompared to the original base populations. In cycle 3 of three populations, 7 to 91% of half-sib families with statistically higher seedling survival r ates than the base populations were considered more resistant than the base populations. Thus, progressive improvement in seedling survival was realiz ed for three populations selected for resistance using three cycles of recu rrent phenotypic selection among and within half-sib families.