Morphological analysis of S9240 tetraploid crested wheatgrass (Agropyron cristatum)

S9240 crested wheatgrass was produced by colchicine-doubling the chromosome number of diploid A. cristatum cv. Parkway, followed by several cycles of selection for height, seed size, floret fertility, and forage yield. Some inclusion of tetraploid A. cristatum cv. Kirk germplasm occurred during the selection cycles. The goal of this study was compare S9240 with other crested wheatgrass cultivars in seed size, height, crown width, tiller number, tiller weight, and ability to emerge from deep seedings. The seed weight of S9240 was significantly (p<0.05) heavier than other tested crested wheatgrass cultivars. In seedings in greenhouse soil flats at a 7.5 cm depth, S9240 showed higher emergence and larger seedlings. S9240 was significantly (p<0.05) taller than other crested wheats in both spaced-plantings and solid swards, and had narrower crowns and fewer, heavier tillers. From the results of the present study, and associated yield trials, S9240 shows potential as a productive hay-type cultivar of crested wheatgrass that can emerge from deeper seedings.