High Temperature Affects Germination in Selected Hard Red Winter Wheat Cultivars.

Early establishment of wheat (Triticum aestivum L.) in the Southern Great Plains of the U.S. is a common practice for forage only or dual-purpose cropping systems. However, early establishment can be problematic because of poor or non-uniform germination due to high soil temperatures.  The objective of this growth chamber experiment was to determine the effects of temperature on germination of 31 hard red winter (HRW) wheat varieties that have been grown in the past or are currently grown in the Southern Great Plains.  Thirty-one entries of HRW wheat were germinated at 25, 30, and 35⁰ C, and germination rates were recorded at 2, 3, and 4 days after initiation(DAI).  Across all wheat entries and temperatures, germination increased as DAI increased. At 35⁰ C 4 DAI, ‘Pete’ and ‘Above’ had greater germination (average 93%), than all other entries except ‘Endurance’ and ‘Sturdy’ (average 86%), while ‘Ruby Lee’ had least germination (13%) than all other entries except ‘Comanche’ (22%).  Selection of cultivars that are less sensitive to high temperature during germination could be beneficial for early fall forage production and breeding programs looking to improve early fall forage production of HRW wheat.