-19- 



Tex. Genetics of Qualitative Characters in American Upland 



Cotton . To make more exact genetic analysis of economic char- 

 acters, usually inherited quantitatively thru (1) development 

 of more multiple dominant & recessive genetic marker lines with 

 simply inherited qualitative characters (known, or to be dis- 

 covered), & (2) establish a series of lines in which specific 

 chromosomes carry known qualitative characters. 

 Agron. 14 Coop. ARS 



Tex. Genetics and Improvement of Cotton . To establish sound 



principles & practices for improvement of cotton thru basic 

 research in cytology & genetics by: (l) maintenance of the 

 Gossypium species, interspecific hybrids & geographic races 

 of Gossypium hirsutum , (2) cytogenetic studies on nature of 

 species differences, & barriers, (3) cytogenetic investiga- 

 tions on effects of individual chromosomes within species & 

 in derivatives of species hybrids, (4) development of marked 

 stocks as an aid in cyto logical & genetical analysis, (5) 

 evaluation of interspecific hybrids, polyploids, & primitive 

 & foreign stocks with respect to their potentialities as 

 sources of characters of economic importance, (6) genetic 

 analysis of desirable characters in interspecific hybrids & 

 in stocks derived from them, & (7) development of primary 

 stocks which possess useful characters, or combinations there- 

 of, not found in American Upland cotton. 



Agron., Ent., Genet., PI. Path. & Physiol. 600 (S-l) Coop. ARS 



Tex. Development of Superior Cotton Varieties for Texas and 



Southwest Conditions . To develop cotton varieties with new or 

 improved economic characters, or combinations of economic char- 

 acters, using field performance, yield in particular, as the 

 principal standard of comparison & selection. 

 Agron. 850 Coop. ARS 



Tex. Spontaneous and Induced Modification of the Gossypium 



Hirsutum Genome . To obtain basic information on the cytogen- 

 etics of Gossypium hirsutum. by following these problems: (l) 

 effect of changes in chromosome number, especially effects of 

 individual chromosomes as studied by their addition to, or sub- 

 traction from, the hirsutum genome, (2) effect of specific chro- 

 mosomes or characters from Asiatic & wild diploid species trans- 

 ferred to the hirsutum genome, by addition or substitution, (3) 

 detection of spontaneous & induced intra- & inter-chromosomal 

 changes, & study of their transmission, (4) detection of gene 

 mutations, spontaneous or induced by radiation or mutagens, (5) 

 improvement of techniques of cytology & inter-specific crossing 

 needed for study of above problems, & (6) building of stocks 

 with each chromosome marked with visible, transmissible cyto- 

 logical aberration. 



Agron. 859 Coop. ARS 



