Plant breeding for organic and sustainable, low-input agriculture

Dynamics of doubled haploidy breeding and molecular cytogenetic approaches vis-a-vis
genetic upgradation of bread wheat for organic and low input farming systems in northwest
Himalayas
Harinder K. Chaudhary, Rakesh K. Chahota, Naval Kishore, Vijay Kumar, Shailesh P. Sood
Molecular Cytogenetics & Tissue Culture Lab, CSK HP Agricultural University, Palampur, India
Bread wheat (Triticum aestivum L.), one of the major cereals of north-west Himalayas is
cultivated under varied agroclimatic situations and farming systems in the hills and mountainous
tracts of this zone. Some of the progressive & tribal farming communities of these Himalayan
mountains have adopted a practice of organic farming system since last decade. The diverse
genotypes of winter and spring wheat ecotypes cultivated in different regions are very low
yielding and highly susceptible to the rusts and powdery mildew hence, there is a dire need to
genetically upgrade these genotypes for developing the elite stocks to be cultivated under organic
and low input farming systems.
The north-west Himalayan germplasm resources in respect of winter and spring wheat ecotypes
and rye have been used for the introgression of the target genes. The breeding programmes have
been accelerated with enhanced precision and efficiency following chromosome elimination
technique (Chaudhary et al., 2005) and novel tools of molecular cytogenetic approach (Mukai et
al., 1989).
The ongoing wheat improvement endeavour for the genetic upgradation of local genotypes in
this Lab has been expedited through the application of novel tools of the doubled haploidy (DH)
breeding and molecular cytogenetic approaches by a team of North-West Himalayan Crop
Improvement & Genome Research Group. The chromosome elimination-mediated approach of
DH breeding has curtailed the time period to develop the new-recombinants derived from the
triticale x wheat (introgressed rye genes into wheat) and winter x spring wheat (introgression of
the gene pools of winter and spring ecotypes) hybridization. The genomic in situ hybridization
(GISH) and fluorescene in situ hybridization (FISH) has further enhanced the efficiency of
selection of elite recombinants carrying targeted introgressions needed for the organic farming
and low input management systems of the north west Himalayan regions. About 150 DH lines
developed in Molecular Cytogenetics & Tissue Culture Lab of this Department by involving the
local land races of winter and spring wheat ecotypes following chromosome- elimination
mediated system and the molecular cytogenetic approaches are being screened under highly
diverse agroclimatic situations for further recommendations to the organic and low input farming
systems.
54