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In vitro shoots of six pear (Pyrus communis L.) cultivars, ‘Conference’, ‘Doyennéd'Hiver’, ‘Passe Crassane’, ‘Bartlett’, ‘AbbéFetel’ and ‘Butirra Precoce Morettini’
were irradiated with gamma rays (3.5 Gy). After three subcultures, microcuttings from the irradiated shoots and from additional
non-irradiated microcuttings were rooted to establish plants for survey orchards. All trees were individually observed for
variation in fruit traits and for productivity. Trees were selected for improved characters related to production such as
early bearing and consistent productivity. Variations observed in fruit appearance concerned degree of russeting, fruit shape
and size. The frequencies of the observed variations in fruit traits depended on the cultivar, ranging from 0.81% in ‘Doyennéd'Hiver’
to 3.64% in ‘Passe Crassane’. Of the 97 variants selected, only two showed chimeral behavior.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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National beef market basket survey 总被引:1,自引:0,他引:1
J W Savell J J Harris H R Cross D S Hale L C Beasley 《Journal of animal science》1991,69(7):2883-2893
Beef retail cases in supermarkets in 12 cities across the United States were surveyed for fat thickness measurements, cut representation, package weights and counts, and case space allocation. Randomly selected retail cuts were purchased and transported to Texas A&M University, where they were dissected into separable components. Samples of ground beef were obtained for chemical analysis. Over 42% of the beef retail cuts had no external fat, and approximately 75% of all cuts were boneless. The overall mean fat thickness for all retail cuts in the beef case was .31 cm, and the overall mean fat thickness for steaks and roasts from the major primals - chuck, rib, loin, and round - was .38 cm. The average percentage of separable lean was 79.0%, separable fat was 12.3%, and bone and connective tissue was 8.7%. Retail cuts had more than twice as much separable seam fat as separable external fat. Beef steaks and roasts had 27.4% less separable fat than values from USDA Agriculture Handbook 8-13. Of the ground beef surveyed, 37% was regular, 40% was lean, and over 22% was extra lean. Retail ground beef had approximately 10% less fat than values from USDA Agriculture Handbook 8-13. 相似文献
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