NON-HOMOEOLOGOUS WHEAT-RYE CHROMOSOMAL TRANSLOCATIONS CONFERRING RESISTANCE TO GREENBUG

C-banding and in situ hybridization were used to determine the chromos omal constitution of the greenbug-resistant germplasm GRS 1204. The re sults showed that this line had the radiation-induced non-homoeologous wheat-rye translocation chromosomes T2AS-1RS . 1RL and T2AL . 2AS-1RS . C-banding analysis further revealed the presence of a wheat-Agropyro n elongatum translocation chromosome T1BL . 1BS-3Ae#1L in line GRS 120 4, that was derived from 'Teewon'. The greenbug resistance of line GRS 1204 is similar to that of line GRS 1201 that was earlier shown to ha ve the greenbug resistance gene Gb6 located on the IRS arm of the whea t-rye translocation chromosome T1AL . 1RS. Because Gb6 in line GRS 120 4 is present on one of the non-homoeologous translocation chromosomes, agronomically line GRS 1201 should be the better adapted source of Gb 6 resistance and be used in cultivar improvement.