الفهرس 
INTRODUCTION
EarlinessOnly 14 pages are availabe for public view
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Abstract
The present investigation ained to study the genetic system controlling sale economic characters in cotton and to estimate the catnants of genetic variability for these characters.
six parental varieties of Gossypirn barhadnese were crossed in a diallel pattern including reciprocals. These six varieties re, four Fyptian varieties; Ashnvuni, Bahtin 101, Giza 75 and Dandara, and twD Soviet varieties 5—6002 and 5320—V.
The results obtained could be si.umnrized as follows:
1) Earliness:
A. Date of first flower: Mditive and dominance gene effects were significant bt the foruer being greater than the latler. The Wr/Vr analysis indicated the presence of partial dominance with Ashnnafli possessin an excess of dominant alleles and 5—6002 exhibiting flora recessive allels, thile the rest of the varieties showed different proportions of dominant and recessive alleles. ,Heritability estimated to be 92.69%, in the broad—s°nse and 81.33% in the narrow-sense. Moreover, 5320—V sho,,ed a significant negative G C A ; indicating that this variety possesses nest favajrable genes for date of the first f1ar.
B. Date of first boll: Mditive gene effects were significant sbile dominance gene effects were not Jirportant for that character. Heritability estiitated to be 68.83% in the broad—sense and 68.01% in the narrow-sense, 5320-V was a gc continer with respect to date of first boll, v4iile Giza 75 was a pcor continer.