March, 1920] GENETICS 93 



G29. Freeman, Geo. F. Heredity of quantitative characters in wheat. Genetics 4: 1-93. 

 Jan., 1919. — Number of reciprocal crosses were made between an Algerian white 

 macaroni wheat, an Algerian red bread wheat, and two white bread wheats, Early 

 Baart and Sonora. All facts observed on inheritance of date of first head, height of 

 plant, width of broadest leaf, are in harmony with hypothesis of segregation of a number of 

 simple Mendelian unit characters. Constants employed to measure variability were stand- 

 ard deviation of time of heading and coefficient of variation of height and leaf width. — All 

 crosses produced normal Fi plants usually somewhat above average in size. Sterile seeds 

 and plants and vegetatively deficient plants occurred in F 2 and F 3 of macaroni-bread wheat 

 crosses, probably the results of recombination of Mendelian unit factors. If blending inher- 

 itance occurred, Fi would have shown abnormality. In nearly all crosses, the behavior of F| 

 cultures from selected F t plants indicated clearly the existence of genetic differences in Fi 

 explainable only as the result of recombination of several unit factors.— Heterozygosity in 

 Fj and F 3 of the macaroni-bread wheat crosses is shown by marked greater variability in 

 hybrid populotions. Differences in variability between F2 and F 3 show increasing homozygosity 

 in Fj. — In size characters, macaroni-bread wheat crosses gave hybrids less in average size than 

 parents but much greater in variability. Bread wheat hybrids were intermediate or greater 

 in size but no more variable than parents. Tall and wide-leaved cultures from genetically 

 equivalent hybrid groups and from pure lines as well were uniformly less variable than short 

 and narrow-leaved cultures. Some suppression factor appears to reduce variability in races 

 with high means resulting from increased vegetative growth. Size factors seem to produce 

 greater variability in combinations producing results below the mean of the hybrid popula- 

 tion. This effect suppressed nearly all extra variability due to heterozygosity in the bread 

 wheat hybrids. Recent literature is reviewed. — Breeze Boyack. 



630. Freeman, G. F. A mechanical explanation of progressive changes in the proportion 

 of hard and soft kernels in wheat. Jour. Amer. Soc. Agron. 10: 23-28. 1918. — See Bot. Absts. 

 3, Entry 2125. 



631. Goodspeed, T. H., and Pirie Davidson. Controlled pollination in Nicotiana. UnivS 

 California Publ. (Bot.) 5: 429-434. 1918.— See Bot. Absts. 3, Entry 998. 



632. Gowen, J. W. Inheritance studies of color and horn characteristics. Maine Agric' 

 Exp. Sta. Bull. 272. 187-148 p., 4 fig. 1918.— See Bot. Absts. 3, Entry 999. 



633. Harland, S. C. Tomato breeding in St. Vincent. Agric. News Barbados 17:4-5. 

 1918. — St. Vincent native tomato is perennial, grows very vigorously and produces smooth, 

 regularly shaped fruits about 1| inches in diameter. Fruits contain many seeds and are very 

 acid in taste. This native variety is unaffected by "Blossom-end rot" although sometimes 

 attacked by the bacterial disease due to Bacterium solanacearum. — Fi and F2 crosses between 

 native variety and Ponderosa have been studied. The Fi generation proved uniform. Qual- 

 ity of fruit and fruit size were intermediate between the parents. Fi fruits were slightly 

 subject to "Blossom-end rot." InF2 segregation occurred for all differential characters. 

 There was an enormous range of sizes and shapes of fruits although no plant produced fruit as 

 large as Ponderosa or as small as the native variety. Segregation occurred for habit of plant 

 and quality of fruit. — Many F 2 plants were attacked by "Blossom-end rot" while others were 

 apparently immune to this affection. Some plants were more resistant to the disease caused 

 by B. solanacearum, than others, although none were immune. — H. K. Hayes. 



634. Harrison, J. B. Seedling sugar canes. Internat. Sugar Jour. 20: 55S-560. 1918. 

 Also: same title. Agric. News Barbados 17: 289-290. 1918. 



635. Hendrickson, A. H. Five years results in plum pollination. Proc. Amer. Soc. Hortic. 

 Sci. 15 (191S) : 65-66. 1919. — Work covers a period of five years involving 100,000 hand-pol- 

 linations to determine effect of selfing and crossing, and more than 175,000 blossoms were 

 counted to secure per cent of set under normal orchard conditions. Results were consistent 



