Introgression of drought tolerance traits into adapted Kenyan chickpea varieties using marker assisted backcrossing (MABC) uri icon

abstract

  • Drought is the major constraint causing considerable yieldreduction in chickpea. Roots play a critical role in enhancingdrought tolerance. The main objective of the study was to introgressdrought tolerant root traits into Kenyan chickpea varietiesthrough marker assisted breeding (MABC). Eight simplesequence repeat (SSR) markers, linked to quantitative trait loci(QTL) for root and yield traits, were used to screen the parentsat ICRISAT, India. In addition, 1144 single nucleotide polymorphicmarkers (SNPs) were also used in genotyping theseparents at Legume Genomics Center, United Kingdom. Crosseswere made between two selected varieties, ICCV 92944 (ChaniaDesi II) and ICCV 00108 (LDT 068) and ?QTL-hotspot? donorparent ICC 4958 that has extensive rooting system. Polymor-In the face of increasing water scarcity, breeding for higher transpirationefficiency (TE), that is, the biomass produced per unitof water transpired, has become crucial. This could be achievedby reducing plant transpiration through a better closure of thestomatal pores at the leaf surface. However, this strategy generallyalso lowers growth, as stomatal opening is necessary forthe capture of atmospheric CO2 that feeds daytime photosynthesis.Here, we considered the reduction in transpiration rateat night (En), when photosynthesis is inactive, as a possiblestrategy to limit water use without altering growth. We carriedout a genetic analysis for En and TE in grapevine, a major cropin drought-prone areas. A 3 year experiment was conducted onthe F1 progeny from a cross between Syrah and Grenache cultiphicSSR and SNP markers were used to select progenies withroot QTL at F1, BC1F1 and BC2F1 that were later advanced toBC2F3. The BC2F3 populations were evaluated for root traitsat Egerton University in randomized complete block designwith two replications in pot experiment. The BC2F3 familieswere significantly different for root dry weight (RDW), shootdry weight (SDW), total plant dry weight (PDW) and root toshoot dry weight (R/S) ratio (R/S) for Chania Desi II x ICC 4958and R/S for LDT 068 x ICC 4958. These lineshad significantlyimproved root traits compared the recurrent parents. MABCis aneffective and efficient method of introgressing complexdrought tolerant traits which leads to improvement in yield especiallyunder drought conditions

publication date

  • 2017