| Morphological analysis of Sando derived wheat x wheat-grass
hybrids K. L. MEHRA1) and J. S. BAKSHI2) Oklahoma State University, Stillwater, Oklahoma, U.S.A. A collection of 542 wheat x wheat-grass derivatives have been maintained at the Oklahoma Agricultural Experiment Station since 1955. These hybrids were made by Dr. W. J. Sando of the United States Department of Agriculture (retired) by crossing various species of the genus Triticum with its related genera in different combinations. The bulk of the material is, however, composed of the derivatives of the crosses between the species of the genera Triticum and Agropyron. Although this material represents a valuable source of germplasm which could be of immence value in the wheat improvement programs, relatively little is known about the nature of the genetic diversity prevalent in these plants. In studying such populations ' plant type ' has been used by most of the workers as the criterion to classify the individual plants into various categories. Schmidt et al. (1953), Marshal and Schmidt (1954), and Schlehuber et al. (1959) classified Agrotriticum into three types; grass-like, intermediate and wheat-like. Schlehuber et al. (1959) prepared a key for the identification of 542 wheat x wheat-grass hybrids on the basis of several morphological characters and the leaf rust reaction of individual plants. A preliminary analysis of the morphological data indicated that although several of these plants could be grouped as either wheat like or grass like, some of the plants showed a varying degree of complex combinations of the characters of the two genera, Triticum and Agropyron. The present study was, therefore , undertaken to analyse the pattern of morphological variation present in this collection, and for this purpose an elite population comprising of 40 hybrids selected at random from these derivatives was studied. Agropyron species are generally distinguished by the presence of the following characters ; scabrous foliage, a long but lax spike with a brittle rachis, and straight sided glumes that adhere to the grain and are not beaked. Triticum aestivum varieties usually have a tender foliage, a dense spike with a non-brittle rachis, and glumes that are beaked. The grains thresh from the glumes. |
| 1) Presently, at the Division of Botany, Indian Agricultural Research
Institute, New Delhi 12, India. 2) Presently, at the Wheat Breeding Sub-station, Tutikandi, Simla, India. |
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