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'IDO580' (Reg. no. GP-777, PI 620638) hard white spring wheat (Triticum aestivum L.) was developed by the Idaho Agricultural Experiment Stations and released in February 2003 for use in research and crop improvement programs. IDO580 is a semi-dwarf wheat with near null levels of seed polyphenol oxidase activity (PPO), an enzyme that causes browning reactions prior to cooking in high moisture food products.
IDO580 was derived from the three-way cross, 'Cadoux' (PI 591905)//'Maya 74VM2 made at the University of Idaho, Aberdeen Research and Extension Center in 1996. Cadoux is a soft white semi-dwarf wheat from Australia. Maya 74 is a hard white spring wheat developed by CIMMYT (IWIS, 2004). M2 is a synthetic hexaploid wheat developed at CIMMYT by crossing 'Ruff [T. turgidum subsp. durum (Desf.)] with the CIMMYT Aegilops tauschii (Coss.) germplasm #112. M2, a soft red spring wheat, had been found in previous evaluations to have very low levels of seed PPO activity. Twelve seeds (F^sub 1^) of the three-way cross, designated A96203S, were grown in the greenhouse. Plants (F^sub 1^) with white (F^sub 2^) kernels were evaluated for PPO activity using tyrosine salt solution as a substrate (Mahoney and Ramsey, 1992). Two F^sub 2^ families from two F^sub 1^ plants of A96203S with white grain and low PPO reaction were planted in the field at Aberdeen in 1997. One F^sub 2:3^ seed from each of approximately 200 plants was evaluated for PPO reaction after 24 h in the reaction buffer rather than standard reaction times of 3-4 hr. Seeds without discoloration were removed from the buffer and planted into the greenhouse. The F^sub 3:4^ grain from each plant (approximately 80 plants) was evaluated (3-5 seeds) at harvest to confirm the low PPO reaction. Grain from 73 confirmed plants were planted in the field in 1998 at Aberdeen in single rows, one F^sub 3:4^ plant per row. Nineteen headrows were selected for good agronomic type, resistance to stripe rust [caused by Puccinia striiformis (Westend.)],...