Technology: What is in the Sorghum Pipeline

Technology: What is in the Sorghum Pipeline

Zhanguo Xin Gloria Burow Chad Hayes Yves Emendack Lan Liu-Gitz, Halee Hughes, Jacob Sanchez, DeeDee Laumbach, Matt Nesbitt

ENVIRONMENTAL CHALLENGES REDUCE YIELDS AT EVERY STAGE OF DEVELOPMENT Data Items 2011 2010 SORGHUM - ACRES PLANTED 5,451,000 5,369,000 SORGHUM, GRAIN - ACRES HARVESTED 3,945,000 4,806,000 SORGHUM, GRAIN - YIELD, BU / ACRE 54 71.9 Source: NASS

Germplasm Evaluation: Drought Tolerance: Pre-Flowering Tolerance Post-Flowering Tolerance Cold Tolerance: Germination Vigor Irrigation Scheduling Germplasm Development: Photoperiod Sensitivity Conversion Development of RIL populations for Cold Tolerance Development of Novel Inbred Lines with Improved Yields Development of Annotated Gene Discovery Population

Improving Stand Establishment

Ethiopian Cold Tolerance 2,000 125 25 Cold Germination Field Germination & Vigor

COLD GERMINABILITY OF GERMPLASM Cold Germination at 12 C for 72 h

April 10 2013 April 30 April 11

2015

Chinese Cold Tolerance RIL Populations RTx430 x Gai Gaoliang (Released) BTx623 x Kaoliang (Ready for Release) BTx623 x Hong Ke Zi (Ready for Release) BTx623 x Niu Sheng Zui (1 Year Out)

Quantitative Trait Loci have been identified for cold germination and early season vigor. Burow GB, Burke J., Franks CD, Xin, Z, 2011. Genetic dissection of early-season cold tolerance in sorghum (S. bicolor). Mol. Breeding, 28:391-402

Stand Establishment on Marginal Soils We have recently identified a metabolic marker in sorghum that correlates with biomass accumulation on low nitrogen soils during the first three weeks following emergence.

Summary We have identified sorghum lines with excellent germination at low temperatures. We have identified sorghum lines with excellent vigor at low temperatures. We have mapped quantitative trait loci for cold tolerance during germination. We have identified a metabolic marker that correlates with improved seedling development in marginal soils having low nitrogen levels.

Improving Drought Tolerance

Seasonal Rainfall Patterns EARLY SEASON MOISTURE VARIABLE SEASON MOISTURE LATE SEASON MOISTURE

Seasonal Rainfall Patterns EARLY SEASON MOISTURE Post-Flowering Drought Tolerance VARIABLE SEASON MOISTURE Pre- and Post-Flowering Drought Tolerance LATE SEASON MOISTURE Pre-Flowering Drought Tolerance

Sorghum Responses to Drought Symptoms of pre-flowering drought stress: leaf rolling, uncharacteristic leaf erectness, leaf bleaching, leaf tip and margin burn, delayed flowering, saddle effect, poor panicle exsertion, panicle blasting and floret abortion, a nd reduced panicle size. Post-flowering water-deficit stress can have direct effects on grain size, as well as effects on harvest due to premature plant death, increased susceptibility to charcoal rot, and lodging, all of which effect yield potential.

PRE - POST- SCENECENT STAY-GREEN

SORGHUM DROUGHT TOLERANCE BIOASSAY DEVELOPED Researchers at the Cropping Systems Research Laboratory developed an assay to identify staygreen sorghums without the requirement of post flowering water stress.

Leaf Dhurrin Content is a Quantitative Measure of the Level of Pre- and Post-flowering Drought Tolerance in Sorghum. Crop Sci. 53:1056 1065 Dhurrin Post-Flowering Tolerance Pre- and Post- Flowering Tolerance Dhurrin Determinations: Conversion Panel Association Panel BTx 642 * Tx7000 RILs SC 56 * Tx7000 RILs Ethiopian Collection KSU RILs BTx623 * Niu Sheng Zui RILs CSRL Breeding Lines AIMS Lines Industry Lines Sudanese Lines Pre-Flowering Tolerance

Natural Variation in Synthesis and Catabolism Genes Influences Dhurrin Content in Sorghum (Sorghum bicolor L. Moench) Genome-wide association analysis (GWAS) using a panel of 700 diverse converted sorghum lines. Genes for biosynthesis and catabolism are important in determining natural variation for leaf dhurrin in sorghum in different environments.

BTx642/Tx7000 RIL QTL Stay-green (1993-1998) and Dhurrin

Sudanese Stay-Green 367 8 3 Efficiency of Quantum Yield Dhurrin levels

Ethiopian Stay-Green 2,000 125 22 Efficiency of Quantum Yield Maintenance of lower leaves under low light Dhurrin levels

Conversion of Photoperiod Sensitive Stay- Green Ethiopian Lines

Dhurrin Post-Flowering Tolerance Pre- and Post- Flowering Tolerance Pre-Flowering Tolerance

Summary We have identified a relationship between leaf dhurrin levels and the level of post-flowering drought tolerance. We have identified the chromosomal regions associated with dhurrin accumulation and turnover. We have identified and released lines with preand post-flowering drought tolerance.

Sorghum Gene Discovery Population for Trait Improvement We have developed technology to move from Quantitative Trait Loci (QTLs) to specific gene identification and subsequent development of perfect trait markers for molecular assisted breeding.

Sorghum Gene Discovery Population for Trait Improvement BTx623 Plant with target trait F1 Target Trait Gene Other Genes Background SNPs Pooled F2 plants homozygous for target trait

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Protein Content Protein Digestibility Mineral Content (Iron, Zinc, etc.)

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield MODERN SORGHUM HYBRIDS DO NOT SET SEED AT EVERY FLOWER!!!

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Screen Gene Discovery Population for Multi-seed Trait

Sorghum Gene Discovery Population for Trait Improvement BTx623 Plant with msd trait F1 Mutli-seedTrait Gene Other Genes Background SNPs Pooled F2 plants homozygous for msd trait

Sorghum Gene Discovery Population for Trait Improvement Heterozygous Having identified the gene controlling the multiseed trait, we create msd gene specific markers for molecular breeding. msd Wild Type Screen segregating populations of inbreds used for hybrid production for the homozygous msd gene.

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield We can now move the multi-seed trait into any sorghum line. Seed with this trait has been provided to seven sorghum seed companies.

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Protein Content Protein Digestibility Mineral Content (Iron, Zinc, etc.)

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Protein Content Screen Gene Discovery Population for Protein Content Scott Bean, ARS, Manhattan, KS

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Protein Content Protein Digestibility Mineral Content (Iron, Zinc, etc.)

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Protein Digestibility Screen Gene Discovery Population for Protein Digestibility Scott Bean, ARS, Manhattan, KS

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Protein Content Protein Digestibility Mineral Content (Iron, Zinc, etc.)

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Mineral Content (Iron, Zinc, etc.) 18 16 14 12 10 8 6 4 2 0 Fe 16 14 12 10 8 6 4 2 0 Zn Mike Grusak 2014

Sorghum Gene Discovery Population for Trait Improvement Traits of Interest: Yield Protein Content Protein Digestibility Mineral Content (Iron, Zinc, etc.)

Summary The gene discovery library possesses many beneficial traits for sorghum improvement. An efficient pipeline has been established to identify genes underlying important traits. The sequenced population covers over 93% of the genes, enabling in sillico identification of the population for important genes.

Special thanks to the Sorghum Checkoff Program for their support of this research.