Inheritance of race 1.2 Fusarium wilt resistance in four melon cultivars

The resistance to Fusarium oxysporum f.sp. melonis (Fom) race 1.2 has been studied in melons, such as the Portuguese accession ‘BG-5384’ and in the Japanese ‘Shiro Uri Okayama’, ‘Kogane Nashi Makuwa’, and ‘C-211’, since a good characterization of the resistance is necessary before its introgression into commercial varieties. These four melon accessions showed a high level of resistance to races 0, 1, and 2 of Fom, indicating that the partial resistance to the race 1.2 previously detected may not have been race specific. To determine the mode of inheritance of the resistance to Fom race 1.2, the F₁, F₂, BCP_R, and BCP_S generations from the crosses between the four resistant accessions above and ‘Piel de Sapo’, a Fom race 1.2 susceptible melon, were developed. They were subsequently inoculated with two Fom isolates, one from the pathotype 1.2Y and the other from the pathotype 1.2W. The area under the disease progress curve was determined for each inoculated plant, and the data were analyzed. We show that the resistance seen in these accessions is polygenically inherited with a complex genetic control because many epistatic interactions were detected. The three epistatic effects; additivity × additivity, dominance × dominance, and dominance × additivity are present and significant, with differing magnitudes from one cross to the next. The relatively low heritabilities, and these epistatic effects make difficult the improvement of the resistance, from these sources, through a standard selection procedure.     

Does rainbow trout justify its high rank among alien invasive species? Insights from a nationwide survey in Greece

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Lignin-carbohydrate bonds in a residual soda spruce pulp lignin

Summary The behaviour of lignin-polysaccharide complex of spruce wood in soda pulping was studied by the characterization of lignin-saccharide fractions isolated from a series of soda pulps. The dioxane pulp lignins contain 8–14% of carbohydrates in which glucose was the predominant component. Its content increased with increasing degree of delignification indicating the formation of secondary lignin-carbohydrate linkage. Both glycosidic and ether type of bond between residual lignin and cellulose in pulp was proved by methylation analysis of the pulp dioxane lignin.The work was supported by the Slovak Academy of Sciences grant number 2/999389/92.     

Relationship Between Solvent Retention Capacity and Protein Molecular Weight Distribution,Quality Characteristics,and Breadmaking Functionality of Hard Red Spring Wheat Flour

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Mycobacterium bovis cultured from commercially pasteurized cows' milk: laboratory cross-contamination

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European eel distribution and body condition in a river floodplain: effect of longitudinal and lateral connectivity

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