DAW00220 - Barley Grain Defects - Research And Screening Services
Project Start Date | 30 June 2012 |
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Project End Date | 30 June 2015 |
Supervisor Name | Dr Chengdao Li |
Organisation | Department of Agriculture and Food Western Australia (DAFWA) |
Contact name | Chengdao Li |
Region | West |
Summary | Grain defects due to black point (BP), kernel discolouration (KD) or pre-harvest sprouting (PHS) downgrade malting barley to feed category causing losses of millions of dollars across Australia. To limit losses, several barley germplasm sets were evaluated and tolerant genotypes were identified. Environments and genotypes were grouped into various risk groups of BP or KD. Genetic factors linked with tolerance to BP, KD or PHS were mapped on various chromosomes. This included grain colour linked quantitative trait loci (QTL) on chromosomes 2H, 3H, 4H, 5H, 6H and 7H. The key gene for PHS was identified. Results from this project will play key roles in developing new varieties with tolerance to grain defects and thus reduce losses. |
Conclusions | 1. Barley genotypes varied significantly for tolerance to barley grain defects. |
Recommendations | Grain trait defects such as BP, KD and PHS vary strongly from location to location, and from season to season. Rainfall during the harvesting period in particular is one of the most important environmental factors that causes grain defects. Replication of trials across regions and sites has been adopted in this project. However, to cater for seasonal variation effects at the same or similar trial locations, studies on traits such as BP, KD and PHS affected by seasonal variability need to be replicated across seasons across four times. |
Project Outcomes | Several barley genotypes were identified with tolerance to BP, KD or PHS, collectively called grain defects. Although environmental variation played dominant roles in the observed variations, particularly in BP and KD, tolerance to grain defects was controlled by genetic factors. Genetic factors for grain defects were mapped as QTL. New molecular InDel markers and SNP markers were developed and delivered to the breeding programs. Genotypes including Australian barley varieties, advanced breeding lines from Australian barley breeding programs, as well as trial environments, were classified into different risk groups associated with BP or KD. Grain defect resistant genotypes and associated genetic factors, information on varietal, breeding lines and environmental vulnerability to grain defects will certainly play important roles in developing new barley varieties with resistance to grain defects. |
Achievement/Benefits | BP and dark tip BP, KD and PHS, collectively called grain defects, downgrade malting barleys to feed category. BP is characterised by darkening of the grain tip which can be associated with, but is not caused by, fungal staining of the grain. KD is caramelisation of the whole grains as grain colour changes from a light straw colour of bright grain to a deep yellow or brown of badly weathered grain. Weather stained barley grains often have poor germination energy and vigour, and low post-harvest dormancy and steeps at a faster rate. Weather-bleached barley is also associated with grain defects and often exhibits PHS damage. PHS is germination of matured grain before harvesting. PHS has traditionally been at acceptable levels in several Australian barley varieties, unlike the Canadian barley varieties that typically experience PHS problems in Harrington and its derivatives. Canadian barley varieties are parents of two Australian barley varieties, Hamelin and Flagship that were released by the western and southern barley breeding programs, respectively. Both varieties have excellent malting quality standards, but they are susceptible to PHS. Gairdner has also had PHS problems in the northern region and the southern barley growing areas. The problem of PHS in Australian barley varieties increased the likelihood of PHS susceptibility genes perpetuating in future barley varieties. (1) Identify germplasm with novel resistance to KD and BP, characterise them genetically and deliver the germplasm to Australian barley breeding programs with molecular markers. (2) Identify QTL (non-5HL) conferring resistance to PHS, validate and characterise genetically, and deliver germplasm to Australian barley breeding programs with molecular markers. (3) Develop efficient screening methods and nurseries, screen breeders' advanced breeding lines and current varieties to understand the grain defect risk for barley growers. (1) International barley varieties from Europe, North America, China and Australian. (2) Advanced breeding lines from Australian barley breeding programs. (3) Mundah and Keel (MK) doubled haploid (DH) population. (4) Flagship and ND (NF) DH population. (5) Vlamingh and Buloke (VB) population. (6) Barley entries in the National Variety Trials (NVT) system. (7) Buloke and mutant line of pale-bright husk. Each of the germplasm sets was evaluated in several trial sites with 34 different environments during the 2012 to 2014 growing seasons in QLD and WA. Phenotypic data of BP, KD or PS were recorded on samples collected from across environments. In addition, all the germplasm sets were studied genetically in order to identify genetic factors linked with BP, KD or PHS. |
Additional Information | Publications Gong X et al. (2014). Seed dormancy in barley is dictated by genetics, environments and their interactions. Euphytica 197: 355. Attachment Angessa T et al. (2015). Barley grains defect due to kernel discoloration and black point. An Industry Report Prepared for GRDC. Murdoch University. |
Published Date | 16 July 2018 |
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