Waterlogging tolerance at germination in pea

Transcription

1 Waterlogging tolerance at germination in pea Md Shahin Uz Zaman PhD Candidate School of Agriculture and Environment Professor William Erskine Dr Imran Malik Dr Parwinder Kaur

2 Acknowledgements ACIAR UWA Tissue culture group Plant growth facilities staff BARI My Supervisors

3 Overview Background of the project Proposed research plan Progress to date

4 Dominant Cropping pattern in Bangladesh Rice-legume-legume/other crops (medium low land) Vegetable-vegetable-legume/other crops (upland) Rice-fallow-rice (low land) New idea: Rice-pea-rice (low land)

5 Pea sowing 2-3 weeks prior to rice harvesting Fallow days Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Monsoonal rice Harvest in November Relay cropping Relay pea Irrigated rice Planting about 15 th February

6 NL days BM days Genotypic variation in relay cropping

7 Waterlogging in dryland agriculture Sandy soil Clay layer Duplex soil type

8 Confirmation of waterlogging (WL) tolerance at germination Identify the mechanism of waterlogging tolerance by whole genome transcriptome profiling Assessing genotypic variability to waterlogging tolerance by screening a diversity panel of pea germplasm Genetic basis of WL tolerance by genome wide association mapping

9 Confirmation of waterlogging (WL) tolerance at germination Treatment: Genotypes: 3 (BM-3, NL-2 and Kaspa WL duration: 0, 4 and 8 days then draining NL-2 BM-3

10 Percent germination ns ns ns ns ns ns BM- 3 NL-2 Kaspa b b 20 0 Drained control 4 days WL 8 days WL a

11 Previous findings Glasshouse observation Seed coat color Leakage of seed solutes Enzymatic activities Mechanism at molecular level? Leakage of seed solutes BM-3 NL Kaspa

12 Identify the mechanism of waterlogging tolerance by whole genome transcriptome profiling Treatments: 2 (waterlogged and drained control) Time point: 4 (12 h, 24 h, 48 h and 96 h) Genotypes: 3 (two WL tolerant and one sensitive) Seed collection: WL soil and drained soil at each time point

13 Common and specific genes differentially expressed with logfc 2 Highly significant numbers (logfc 4): Tolerant genotypes: 43 and Sensitive genotype: 134

14 Key gene expression under WL stress Tolerant Sensitive Protein Upregulated Downregulated Lipid Downregulated Upregulated Carbohydrate Lignin and Phenolic precursors Downregulated Upregulated Non Functional Downregulated Seed solutes

15 Assessing genotypic variability to waterlogging tolerance by screening diversity panel of pea germplasm Treatment: Genotypes: 110 (diversity panel of pea) WL duration: 8 days

16 Percent germination Variation of WL tolerance

17 Traits associated with WL tolerance WL germination Traits Flower color Leaf axil color WL germination Flower color 0.50*** Leaf axil pigment 0.52*** 0.86*** Seed coat color 0.56*** 0.91*** Tolerant Sensitive Tolerant Sensitive 0.91*** Tolerant Sensitive

18 Genetic basis of WL tolerance by genome wide association mapping Populations used: Diversity panel of 110 germplasm Bi-parental population

19 Bi-parental population development through rapid generation protocol Crossing Confirmation of F1 7 th generation Fourth to Sixth Generation Second generation Third generation

20 Conclusion WL major problem to intensify pea in rice fallows and duplex soil in dryland agriculture Genotypic variation to WL tolerance found at germination in peas New mechanism for tolerance identified by transcriptome analysis Tolerant source and associated morphological traits identified Molecular markers and genomic loci associated with tolerance being mapped through GWAS

21 Take-Home Message Contribute to develop WL tolerant pea varieties for rice fallows in South Asia and duplex soil in Australia and others Can be translated to related legume species and other crop Will increase yield by reducing crop damage by waterlogging

22 THANK YOU FOR LISTENING Q