- 468 
Journal of Agricultural Research 
Vol. XXIV, No. 6 
SUMMARY 
(1) The segregation for growth-habit characters in the progeny of a 
cross between a winter and a spring wheat accords with Mendelian 
laws. The results indicate the presence of multiple factors for this 
character. 
(2) Homozygous types for both spring and winter characters were 
obtained in the F3. In the Fj, some plants appeared which were homozy¬ 
gous in F3 for a heading period which was 5 weeks later than that of 
the Marquis (spring) parent. 
(3) Kanred is an awned winter common wheat, while Marquis is an 
awnless spring common wheat. In the progeny of this cross there was 
no correlation between growth habit and presence of awns. 
(4) The segregation for rust reaction to Biologic Form I in the progeny 
of a cross between Kanred and Marquis wheats shows a simple Mendelian 
ratio of approximately three immune plants to one susceptible plant. 
There is a clear dominance of immunity over susceptibility, since there 
are no intermediate types of infection with this rust form. 
(5) The progeny of this cross were inoculated with several biologic 
forms of stem rust and show that the reaction of the host to all of these 
forms is inherited as a single genetic factor. 
(6) In the F3 some of the hybrid families were homozygous for the 
spring habit of the Marquis parent and for the rust resistance of the 
Kanred parent. 
(7) There was no correlation between the inheritance of growth habit 
and the manner of reaction to stem rust. 
(8) These facts further demonstrate that varieties of common wheat 
may be produced synthetically which will be resistant to a large number 
of the biologic forms of stem rust, Puccinia graminis tritici, 
LITERATURE CITED 
(1) Biffin, R. H. 
1907. STUDIES IN THE INHERITANCE OF DISEASE-RESISTANCE. In JoUT. Agr. 
Sci., V. 2, p. 109-128. Bibliographical footnotes. 
(2) Evans, I. B. Pole. 
191I. SOUTH AFRICAN CEREAD RUSTS, WITH OBSERVATIONS ON THE PROBLEM OF 
breeding rust-resistant wheats. In Jour. Agr. Sci., v. 4, p. 95- 
104. Bibliography, p. 104. 
(3) Fruwirth, C. 
1918. DIE UMZUCHTUNG VON wintergetrEide IN sommErgetrEide. In Ztschr. 
Pflanzenzuchtung, Bd. 6, p. 1-46. Bibliographical footnotes. 
(4) 
1910. ALLGEMEINE ZUCHTUNGSLEHRE DER LANDWIRTSCHAFTLICHEN KULTUR- 
pflanzen. Ed. 5, xviii, 442 p., 89 fig., 8 pi. Berlin. (Handbuch der 
landwirtschaftlidaen Pflanzenzuchtung, Bd. i). 
(5) Gaines, E. F. 
1917. INHERITANCE IN WHEAT, BARLEY AND OAT HYBRIDS. Wash. Agr. Exp. 
Sta. Bui. 135,61 p., 9fig. Bibliography, p. 60-61. 
(6) Garner, W. W., and Allard, H. A. 
1921. FLOWERING and FRUITING OF PLANTS AS CONTROLLED BY THE LENGTH OF 
DAY. In U. S. Dept. Agr. Yearbook, 1920, p. 377-400, 9 fig. 
(7) Hayes, H. K., Parker, John H., and Kurtzweil, Carl. 
1920. GENETICS OF RUST RESISTANCE IN CROSSES OF VARIETIES OF TRITICUM 
VULGARE WITH VARIETIES OF T. DURUM AND T. DICOCCUM. In Jour. 
Agr. Research, v. 19, p. 523-542. Literature cited, p. 541-542. 
(8) Levine, M. N., and Stakman, E. C. 
1918. A THIRD BIOLOGIC FORM OF PUCCINIA GRAMINIS ON WHEAT. In Jour. Agr. 
Research, v. 13, p. 651-654. 
