Genetic architecture of factors underlying partial resistance to Alternaria leaf blight in carrot.

In most production areas, Alternaria leaf blight (ALB) is recognized as the most common and destructive foliage disease in carrot. To assess the genetic architecture of carrot ALB resistance, two parental coupling maps were developed with similar number of dominant markers (around 70), sizes (around 650 cM), densities (around 9.5 cM), and marker composition. The F(2:3) progenies were evaluated in field and tunnel for two scoring dates. The continuous distribution of the disease severity value indicated that ALB resistance is under polygenic control. Three QTLs regions were found on three linkage groups. Two of them were tunnel or field specific and were detected only at the second screening date suggesting that the expression of these two QTLs regions involved in resistance to Alternaria dauci might depend on environment and delay after infection

Peut-on cartographier les facteurs de résistance de la carotte à Alternaria dauci, à l'aide de marqueurs dominants sur une descendance F2?

Peut-on cartographier les facteurs de résistance de la carotte à Alternaria dauci, à l'aide de marqueurs dominants sur une descendance F2?Peut-on cartographier les facteurs de résistance de la carotte à Alternaria dauci, à l'aide de marqueurs dominants sur une descendance F2

Campagne Hydrofast: Etudes quantitatives de l'activite hydrothermale sur la ride-est pacifique a 13 degree Nord

Hydrofast Cruise of the R.V. Jean Charcot addressed the important problem of the variation of hydrothermal activity along the strike of the Ridge over a distance of 100 km with respect to the structure of the ridge axis. This cruise was conducted along the East Pacific Rise between the OSC at 11 degree 45'N and the topographic high at 13 degree N. To reach that objective, a new tool, the dynamic hydrocast, was used. This technique obtains average samples mile per mile, horizontally, at 4 different depths above the bottom. Temperature is recorded at the same time. In addition, the side-scan sonar SAR gave a continuous picture of the fissures along the strike and of the different facies within the 300 to 400 m width of the axial graben. A magnetometer and a thermistance array towed with the SAR completed the set of data