Authors: M Addisu J W Snape J R Simmonds M J Gooding
Publish Date: 2009/09/21
Volume: 172, Issue: 2, Pages: 169-181
Abstract
Near isogenic lines NILs varying for reduced height Rht and photoperiod insensitivity PpdD1 alleles in a cv Mercia background rht tall RhtB1b RhtD1b RhtB1c Rht8c+PpdD1a RhtD1c Rht12 were compared for interception of photosynthetically active radiation PAR radiation use efficiency RUE aboveground biomass AGB harvest index HI height weed prevalence lodging and grain yield at one field site but within contrasting ‘organic’ vs ‘conventional’ rotational and agronomic contexts in each of 3 years In the final year further NILs rht tall RhtB1b RhtD1b RhtB1c RhtB1b+RhtD1b RhtD1b+RhtB1c in Maris Huntsman and Maris Widgeon backgrounds were added together with 64 lines of a doubled haploid DH population Savannah RhtD1b × Renesansa Rht8c+PpdD1a There were highly significant genotype × system interactions for grain yield mostly because differences were greater in the conventional system than in the organic system Quadratic fits of NIL grain yield against height were appropriate for both systems when all NILs and years were included Extreme dwarfing was associated with reduced PAR RUE AGB HI and increased weed prevalence Intermediate dwarfing was often associated with improved HI in the conventional system but not in the organic system Heights in excess of the optimum for yield were associated particularly with reduced HI and in the conventional system lodging There was no statistical evidence that optimum height for grain yield varied with system although fits peaked at 85 and 96 cm in the conventional and organic systems respectively Amongst the DH lines the marker for PpdD1a was associated with earlier flowering and just in the conventional system also with reduced PAR AGB and grain yield The marker for RhtD1b was associated with reduced height and again just in the conventional system with increased HI and grain yield The marker for Rht8c reduced height and in the conventional system only increased HI When using the System × DH line means as observations grain yield was associated with height and early vegetative growth in the organic system but not in the conventional system In the conventional system PAR interception after anthesis correlated with yield Savannah was the highest yielding line in the conventional system producing significantly more grain than several lines that out yielded it in the organic system
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