Guar [Cyamopsis tetragonoloba (L.) Taub.] is one of the most important industrial crops due to its richness in gum. Understanding the inheritance of gum content is a key to its successful genetic improvement. Gum co...Guar [Cyamopsis tetragonoloba (L.) Taub.] is one of the most important industrial crops due to its richness in gum. Understanding the inheritance of gum content is a key to its successful genetic improvement. Gum content expression is reported to be controlled by additive, dominant, and epistatic effects, and modified by the environment, fg%, a relative gum content calculated by comparing with the gum content of Kinman was used as gum content (%) in this experiment. Reciprocal crosses of two lines of guar, PI 217923 and Lewis, were made to study the heritability of gum content (fg%). fg% of four plant introductions and four commercial varieties were studied in Lubbock in 1999-2002. Estimates of broadsense heritability (h^2 b,s.) of fg% in Lewis x PI 217923 and PI 217923 x Lewis were 75.53 and 52.74%, respectively. Estimates of narrow-sense heritability (h2 n.s.) of fg% were 40.00 and 29.00% thr Lewis x PI 217923 and PI 217923 x Lewis, respectively. At least one pair of genes were estimated to control the fg% expression in these two crosses, Significant differences of fg% were found among these eight entries. PI 217923 was found to have the highest fg% among the eight entries.展开更多
Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sa...Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sauces, improvement of the swelling of maize and bean cakes) and in the process of decantation of traditional beer. In order to valorize these barks in dried form, study of the effect of drying temperature on the rheological properties of their gums was carried out. In this respect, the fresh barks were dried at 40℃, 50℃, 60℃, 70℃ and 80℃ and the viscosity of their extracts was measured. The drying kinetic of the barks showed two falling rate periods represented by two drying constants?k1 and k2. The absolute viscosity of the extracts decreased beyond drying temperatures higher than 70℃ and 80℃respectively for T cordifolia and B. Thermifolia. The decreasing viscosity is attributed mainly to a reorganization of polysaccharide chains. The temperatures range lower than 70℃ could be retained to dry the barks and to extract gums without deteriorating their properties.展开更多
基金supported by the Halliburton Energy Services,Inc.,USA
文摘Guar [Cyamopsis tetragonoloba (L.) Taub.] is one of the most important industrial crops due to its richness in gum. Understanding the inheritance of gum content is a key to its successful genetic improvement. Gum content expression is reported to be controlled by additive, dominant, and epistatic effects, and modified by the environment, fg%, a relative gum content calculated by comparing with the gum content of Kinman was used as gum content (%) in this experiment. Reciprocal crosses of two lines of guar, PI 217923 and Lewis, were made to study the heritability of gum content (fg%). fg% of four plant introductions and four commercial varieties were studied in Lubbock in 1999-2002. Estimates of broadsense heritability (h^2 b,s.) of fg% in Lewis x PI 217923 and PI 217923 x Lewis were 75.53 and 52.74%, respectively. Estimates of narrow-sense heritability (h2 n.s.) of fg% were 40.00 and 29.00% thr Lewis x PI 217923 and PI 217923 x Lewis, respectively. At least one pair of genes were estimated to control the fg% expression in these two crosses, Significant differences of fg% were found among these eight entries. PI 217923 was found to have the highest fg% among the eight entries.
文摘Triumfetta cordifolia and Bridelia thermifolia are two shrubs from tropical region of Africa. Their gums are traditionally extracted from fresh barks and used in traditional recipes (thickening and aromatization of sauces, improvement of the swelling of maize and bean cakes) and in the process of decantation of traditional beer. In order to valorize these barks in dried form, study of the effect of drying temperature on the rheological properties of their gums was carried out. In this respect, the fresh barks were dried at 40℃, 50℃, 60℃, 70℃ and 80℃ and the viscosity of their extracts was measured. The drying kinetic of the barks showed two falling rate periods represented by two drying constants?k1 and k2. The absolute viscosity of the extracts decreased beyond drying temperatures higher than 70℃ and 80℃respectively for T cordifolia and B. Thermifolia. The decreasing viscosity is attributed mainly to a reorganization of polysaccharide chains. The temperatures range lower than 70℃ could be retained to dry the barks and to extract gums without deteriorating their properties.