Plant & Animal Genomes XVII Conference Plant & Animal Genomes XVII ConferenceJanuary 10-14, 2009
Town & Country Convention Center
San Diego, CA
Bradley J Till , Joanna Jankowicz-Cieslak , Marta Brozynska , Owen Huynh , Souleymane Bado , Mirta Matijevic , Rownak Afza , Chikelu Mba
The advancement of genomic techniques and information is facilitating gene function analysis and breeding in understudied crops. Our laboratory is currently optimizing the high-throughput reverse genetics platform known as TILLING (Targeting Induced Local Lesions In Genomes) for banana and cassava. Our main focus in banana is understanding resistance to black sigatoka disease. We established a population of ~800 EMS mutagenized triploid plants of the Grand Naine variety that are easily propagated by in vitro culture. Screens for mutations were done in plants pooled eight-fold. We screened ~3Mb of genomic sequence and identified several putative mutations that await validation. Data on mutation frequency and spectrum will be used for optimizing protocols and for planning larger scale populations, including the black sigatoka resistant diploid Calcutta 4. This variety may be useful in uncovering the genetic basis of disease resistance. For cassava, we have approximately 1000 mutagenzied plantlets that will be screened for mutations in the near future. Our focus is to identify genes involved in starch biosynthesis. Concurrently, we are screening for natural nucleotide polymorphisms in accessions of banana, cassava, and rice using a method called Ecotilling. To further the establishment of reverse genetics in understudied crops, we provide training to other groups. We are also working on developing collaborative services where researchers can send samples to our facility for screening. For a pilot study, we have successfully screened mutagenized cassava samples from three different countries. This suggests that the approach could be broadly applicable.