COWPEAS, SOYBEANS, AND VELVET BEANS 145 



Mendelian way and hence is relatively easy to transfer and iso- 

 late by crossing and selection. 



Some Results of Selection and Crossing. The characteristics 

 of an ideal cowpea are resistance to nematodes and wilt, upright 

 habit of growth with pods borne high, and high yielding ability. 

 With this ideal in view the United States Department of Agri- 

 culture has conducted extensive investigations. 



Attention was first called to the Iron cowpea by T. S. Williams 

 of Monetta, S. C. He found it would thrive on "pea-sick" soil 

 where other varieties were a complete failure. On learning of 

 this resistant variety, Orton gave it a thorough trial and found 

 it possessed resistance. Measures were immediately taken to in- 



FIG. 33. Iron cowpea vs. Black and Taylor, showing comparative resistance 

 to the wilt and the root-knot. Iron in center and Black and Taylor at right 

 and left respectively. (After Orton.) 



crease and disseminate the Iron cowpea generally throughout the 

 southern United States. Because the Iron variety did not pro- 

 duce as large yields of seed and forage as some other varieties 

 such as Unknown, breeding was resorted to for the purpose of 

 producing a high-yielding resistant strain (Webber and Orton, 

 1902; Orton, 1902). 



In addition to disease resistance this variety has a relatively 

 upright, bushy habit of growth but the seed production is low. 

 At first a large number of sprawly forms, such as Red Ripper, 

 Clay, Black, and Unknown were crossed with Iron. None of 

 the segregates from these crosses proved particularly desirable. 

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