UNITED STATES DEPARTMENT OF AGRICULTURE 
, BULLETIN No. 1046 
Contribution from the Bureau of Plant Industry ‘ 4 <a 
WM. A. TAYLOR, Chief, in cooperation with the 
Kansas Agricultural Experiment Station 
Washington, Dac. Vv May, 1922 
RUST RESISTANCE IN WINTER-WHEAT VARIETIES.! 
_ By Leo E. Metcuers, Plant Pathologist, and Joun H. Parker, in Charge of Crop 
Improvement, Kansas Agricultural Experiment Station; Agents, Office of Cereal 
Investigations. 
CONTENTS. 
Page | Page 
scope of the investigation.................-. 1 Evidence of specific rust resistance.......... 24 
Review of theliterature...................-. 2 | Agronomic value of Kanred wheat.......... 26 
INUITSery Experiments 2.3. 5. sas... oce ewes cece e AS SSUMUMNATY, + sacs sae see re ocmeeisee Osta cece eens 27 
Greenhouse experiments. .............02.208 14 | Eiterature cited)... so: 2eacaea cers esicosacaee 30 
Comparison of nursery and greenhouseresults 23 | 
SCOPE OF THE INVESTIGATION. 
A project to determine the rust resistance of existing varieties of 
winter wheats and to breed new varieties for rust resistance was 
begun in 1911 at the Kansas Agricultural Experiment Station, in 
cooperation with the Office of Cereal Investigations of the United 
States Department of Agriculture. The first two years were devoted 
to preparatory work, when no infection of stem rust was produced. 
The writers ? took charge of the work in 1913, and the data given 
herein are those obtained since that time. , 
The investigation outlined in 1913 had two major purposes: (1) 
To study the rust resistance of about 130 varieties and strains of 
winter and spring wheats, particularly to the stem rust, Puccoma 
graminis tritics Erikss. and Henn.,? in the field and in the green- 
house; and (2) to study the inheritance of rust resistance in wheat 
and to produce hybrids adapted to commercial use. 
1 Paper No. 183 of the Department of Botany and Plant Pathology and No. 136 of the Department of 
Agronomy, Kansas Agricultural Experiment Station. 
2 The writers wish to acknowledge their indebtedness to Mr. Victor H. Florelland Mr. M.N. Levine, of 
the Office of Cereal Investigations, who assisted in the greenhouse studies and in other phases of the 
investigation. 
3 Puccinia graminis tritici, as used in this bulletin, has reference to those strains of stem rust used in 
the experiments in 1915, 1916, and 1917. In 1915 a strain was used to which Kanred, P1066, and P1068 
were only partially resistant, while in 1916 and 1917 strains were used to which these varieties were very 
resistant. The strains used in 1916 and 1917 may have been one or more;of the several strains which at 
present are known not to cause normal infection of these varieties. 
7925i1—22— Bull. 1046——1 
