Characterization of Siberian wheatgrass germplasm from Kazakhstan (Poaceae: Triticeae)

Siberian wheatgrass [Agropyron fragile (Roth) Candargy] is known for its establishment and persistence on sandy soils under severe water limitations. Morphology, cytology, and forage and seed characteristics were studied on 59 accessions (JA) of Siberian wheatgrass collected on sandy soils in the desert areas of western Kazakhstan. Plants were grown at Nephi, Ut., from 1993 to 1996 and compared with the check cultivars of Vavilov and P-27 Siberian wheatgrass, and Nordan crested wheatgrass [A. desertorum (Fisch. ex Link) Schultes]. All JA-accessions were autotetraploids, 2 (n) under bar = 4 (x) under bar = 28. The most frequently observed meiotic association was 6 bivalents + 4 quadrivalents. The JA-accessions were morphologically diverse, ranging from short to tall in stature and from dark-green, glaucous to blue-green, strongly pubescent. Mean forage yield, crude protein, and dry matter digestibility were generally lower in the JA-accessions than the check varieties. Entry x year interactions were nonsignificant (P > 0.05) for all measured forage variables. Entries were significantly (P < 0.01) different for dry matter production. Seed weight of Vavilov and mean seed weight of JA-accessions were significantly (P < 0.01) greater than that for the check cultivars P-27 and Nordan. Entries that were highly pubescent had the heaviest seed and greatest capacity to emerge from a 7.6-cm planting depth. Seed yield plant(-1) was significantly (P < 0.01) lower in the JA-accessions than cultivars Vavilov, P-27, and Nordan. Sufficient variations exist for seed yield, seed weight, seedling vigor, and forage yield within the JA-accessions to allow for the development of an agronomically suitable, drought tolerant Siberian wheatgrass through selection.