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Show study note s radical change in plant sex According to geneticists, some plants are like humans--they have chromosomes that determine deter-mine their sex. Today, an individual can undergo surgery for a change in sex, but all some plants have to do to change is spend a cold winter in Utah. A Forest Servic e researcher has reported 1 1 dramatic number of change s in the sex of one of Utah' s most valued range plants - the fourwing saltbush. Dr. Durant McArthur, geneticist on the staff of the In-termountain In-termountain Forest and Range Experiment Station, found that 90 plants in an experimental plot of about COO changed from female to male or to a bisexual state after the winter of 1973. McArthur attributes the change to stress induced by the mild, damp autumn of 1972, followed by a very cold winter, when temperatures dipped as low as 2.r degrees below zero. "Some sex change is normal for this species," McArthur says, "but we have never documented anything of this scope." Dr. M c A r t h u headquartered at the In-termountain In-termountain Station's Shrub Sciences Laboratory, Provo, has reported his findings in an article published by Heredity, a scientific journal dealing with plant and animal breeding, and with control of hereditary factors in humans. In the article, Dr. McArthur proposes a c h r o m o s o m a 1 sex-determining sex-determining mechanism that explains why some plants change sex to avoid continued environmental stress. The information is expected to assist commercial com-mercial growers cultivating the shrub for seed production. produc-tion. Plants that do not change sex are the best seed producers and should be used in seed orchards. The fourwing saltbush is valued r as a forage plant for wildlife and livestock, and is used to stabilize soils in reclamation of disturbed sites in the West. McArthur's study is part of a research program centered at the Provo Shrub Sciences Laboratory. The Laboratory is the first facility devoted principally to wildland shrub research. Maintained in cooperation with Brigham Young University, it is located on the University's campus in Provo. The location is near the center of the 400 million acres of shrubland in Western United States. |