Čeština
EnglishCharacterization and use of aneuploid tritordeum lines for the localization of resistance to Septoria tritici in Hordeum chilense
Said M., Rubiales D., Cabrera A.
AGRISAFE FINAL CONFERENCE. challenge for training of applied plant scientists. March 21-23 (Budapest) Hungary. : , 2011
Keywords:
Abstract: Fungal diseases are the major biotic factor limiting yield and quality of wheats. Genetic resistance is the most effective method for disease control. In the South of Spain, in Andalusia, the greatest economic losses in wheat are usually due to rust and septoriasis epidemics. Septoria (Septoria tritici) is considered as the wheat pathogen responsible for major yield losses in Spain. The suitable conditions for the development of this disease often coincide with the optimum conditions for the crop, which mainly affecting the yield and quality. Hordeum chilense is diploid wild barley species native from South America. The evaluation for resistance to Septoria of the available disomic addition lines of H. chilense in bread wheat have suggested that chromosome 4Hch contains genes for resistance to this disease. To estimate the effect and arm location on chromosome 4Hch of genes for resistance to Septoria, aneuploid tritordeum (fertile amphiploid H.chilense x T.turgidum) lines involving chromosome 4Hch were used. Tritordeum lines used were: nullisomic for 4Hch (HT-Nulli 4Hch), double nullisomic for 2Hch-4Hch (HT-Double Nulli 2Hch-4Hch), ditelosomic for 4HchS (HT-Ditelo 4HchS) and a terminal deletion of 4HchL (HT-Del 4HchL). Tritordeum line HT31 and disomic addition lines for chromosome 4Hch in Chinese Spring (CS+4Hch) were used as control. All lines were arranged in field experiment in randomized complete block design with three replications. Durum wheat variety Meridiano, a variety of wheat highly susceptible to Septoria, was used as spreader. Resistance to Septoria was evaluated by estimating the maximum value of disease severity in each plant (percentage of leaf area covered with pustules). Lines were divided into a set of orthogonal components of two groups: a group of lines carrying 4Hch and the other group without this chromosome. The group of lines carrying 4Hch showed significantly lower severity levels than the group of lines which does not carrying this chromosome. By calculating the coefficient of determination (R2), it has been observed that the chromosome 4Hch explains 86% of the variation between the two groups of lines for resistance to Septoria. These results confirm the positive effect of chromosome 4Hch in resistance to Septoria. The positive effect was observed in both lines carrying the entire chromosome in the genetic background of bread wheat (CS+4Hch) and the tritordeum line (HT31). There are no significant differences for the percentage of severity between these lines and the line where the long arm was absent (HT-Ditelo 4HchS) or deficient (HT-Del 4HchL) suggesting that Septoria resistance genes may be located in the short arm of chromosome 4Hch.
DOI:
Fulltext: contact IEB authors
IEB authors: Mahmoud Said
AGRISAFE FINAL CONFERENCE. challenge for training of applied plant scientists. March 21-23 (Budapest) Hungary. : , 2011
Keywords:
Abstract: Fungal diseases are the major biotic factor limiting yield and quality of wheats. Genetic resistance is the most effective method for disease control. In the South of Spain, in Andalusia, the greatest economic losses in wheat are usually due to rust and septoriasis epidemics. Septoria (Septoria tritici) is considered as the wheat pathogen responsible for major yield losses in Spain. The suitable conditions for the development of this disease often coincide with the optimum conditions for the crop, which mainly affecting the yield and quality. Hordeum chilense is diploid wild barley species native from South America. The evaluation for resistance to Septoria of the available disomic addition lines of H. chilense in bread wheat have suggested that chromosome 4Hch contains genes for resistance to this disease. To estimate the effect and arm location on chromosome 4Hch of genes for resistance to Septoria, aneuploid tritordeum (fertile amphiploid H.chilense x T.turgidum) lines involving chromosome 4Hch were used. Tritordeum lines used were: nullisomic for 4Hch (HT-Nulli 4Hch), double nullisomic for 2Hch-4Hch (HT-Double Nulli 2Hch-4Hch), ditelosomic for 4HchS (HT-Ditelo 4HchS) and a terminal deletion of 4HchL (HT-Del 4HchL). Tritordeum line HT31 and disomic addition lines for chromosome 4Hch in Chinese Spring (CS+4Hch) were used as control. All lines were arranged in field experiment in randomized complete block design with three replications. Durum wheat variety Meridiano, a variety of wheat highly susceptible to Septoria, was used as spreader. Resistance to Septoria was evaluated by estimating the maximum value of disease severity in each plant (percentage of leaf area covered with pustules). Lines were divided into a set of orthogonal components of two groups: a group of lines carrying 4Hch and the other group without this chromosome. The group of lines carrying 4Hch showed significantly lower severity levels than the group of lines which does not carrying this chromosome. By calculating the coefficient of determination (R2), it has been observed that the chromosome 4Hch explains 86% of the variation between the two groups of lines for resistance to Septoria. These results confirm the positive effect of chromosome 4Hch in resistance to Septoria. The positive effect was observed in both lines carrying the entire chromosome in the genetic background of bread wheat (CS+4Hch) and the tritordeum line (HT31). There are no significant differences for the percentage of severity between these lines and the line where the long arm was absent (HT-Ditelo 4HchS) or deficient (HT-Del 4HchL) suggesting that Septoria resistance genes may be located in the short arm of chromosome 4Hch.
DOI:
Fulltext: contact IEB authors
IEB authors: Mahmoud Said