Marker-Assisted Pyramiding Resistance Genes Against Angular Leaf Spot and Common Bacterial Blight Disease into Preferred Common Bean Cultivar "REDWOLAITA"
Journal Title: Advances in Crop Science and Technology - Year 2019, Vol 7, Issue 1
Abstract
Angular leaf spot (ALS) caused by Pseudocercospora griseola and common bacterial blight (CBB) caused by Xanthomonas campestris pv phaseoli X. campestris pv. phaseoli var. fuscans are the most economically important diseases of common bean production in Ethiopia. This research was aimed at pyramiding the Phg-2 R gene for angular leaf spot resistance and two CBB major resistance quantitative trait loci (RQTLs) into the background of the most popular and susceptible common bean cultivar “REDWOLAITA” (RW). Marker-assisted Parallel Back Crossing (MAPBC) breeding scheme with three separate parallel backcrossing streams were adopted. This technique accelerated tracking three independent resistance loci linked to g796, SAP6 and SU91 genetic marker from two different donor parents into the RW recurrent parent. The donor parental line VAX-6 with known RQTLs for CBB and tagged by the SAP6 and SU91 genetic markers on linkage groups 10 and 8, respectively was used. The other donor parent MEX-54 with known Phg-2 R gene tagged by the g796 genetic marker at the linkage group 8 was used in the gene pyramiding program. After the BC4 generation, progenies that combined SAP6 and g796 genetic markers were created and selected from the BC4 inter-crossing of progenies. Then, further inter-crossing was made between selected progenies that combined the SAP6 and g796 genetic markers with selected progenies with the SU91 genetic marker. Finally, from this study we developed Monogenic Near Isogenic Lines (MNILs) with R genes tagged by the SAP6, g796, and SU91 molecular markers and Polygenic Near Isogenic Lines (PNILs) with different gene combination. The developed lines include MNILSAP6, MNILSU91 and MNILg796, PNILsSAP6/g796, PNILsSU91/g796, PNILsSAP6/SU, PNILsSAP6/g796/SAP6, with more than 97% genome recovered from the RW genetic background. Marker-assisted backcrossing facilitated selection of progenies that combined good agronomic traits with resistance loci were constructed from the RW common bean cultivar. The developed lines showed high level of disease resistance to the strains of CBB and ALS under the screening conditions. The developed lines will be evaluated under multiple environment under natural epidemics, before varietal release for wider production. We also recommend the developed NILs with RW back ground and known sources of R genes and good agronomic performance could be used as alternative donor parent for the future gene pyramiding program.
Authors and Affiliations
Yayis Rezene, Kassahun Tesfaye, Clare Mukankusi, Paul Gepts
Decade of South Ethiopian Coffee Improvement Activities at Awada Coffee Research Center
Coffee improvement program of Ethiopia was aimed to develop widely adaptable and stable cultivars across all coffee growing regions of the country although there is a significant ecological variation that prevails betwee...
Nitrogen Uptake and Use Efficiency of Irrigated Bread Wheat (Triticum aestivum L.) as Influenced by Seed and Nitrogen Fertilizer Rates at Werer, Afar National Regional State, Ethiopia
An offseason field experiment was conducted in 2015-2016 at Werer Agricultural Research Center Middle Awash, Afar regional state to determine N-uptake and use efficiency of irrigated bread wheat (Triticum aestivum L.) as...
Impact of Zinc and Organic Manure on Wheat Productivity and Soil Fertility
Use of synthetic fertilizers have some problem to farmer due to short residual effect and high cost. Since the farmers used organic manure due to long residual effect but the nutritional requirement is not fulfilling dur...
Herbicide Interactions between Glufosinate and Three Fomesafen-Containing Herbicide Products as Affected by Weed Size and Spray Droplet Size
Two effective herbicides with different sites of action (SOA) are recommended for control of problematic weeds such as Palmer amaranth. When a LibertyLink® soybean variety is planted in the Midsouth, USA, glufosinate is...
Evaluation of Bread Wheat (Triticum aestivum L.) Genotypes for Yield Potential and Related Traits Under High Temperature Stress Condition at Middle Awash, Ethiopia
Information on the extent and performance of genotypes present in a crop species under high temperature stress are essential for effective crop adaptation program. To generate such information 36 bread wheat genotypes wi...