Fig 1.
Schematic representation of barley inflorescence architecture.
(A) Branched grass inflorescence architectures of; two-rowed and six-rowed barley (H. vulgare) spike. (A bottom) Single spike nodes of two- and six-rowed spikes. (B) Representation of the shoot architecture found in grass species.
Fig 2.
Distribution of seed size is altered in row type mutants.
Distribution of seed area ranging from 10–45 mm2 plotted against the average seed number per spike (n≥8 spikes). The spikes used to obtain the frequency distribution of seed size and average seed number per spike were derived from plants grown under outdoor conditions. Fig A-D represents typical seed size distributions measured in all genotypes and backgrounds. (A) Bell-shaped distribution with higher seed number and variance and lower average: e.g. vrs3(int-a.1); (B) bimodal distribution with one peak at a size similar to wild type and one peak at a smaller size, both peaks similar in height: e.g. int-b.3; (C) bimodal distribution with one peak at a size similar to the wild type and one peak at a smaller size accounting for approximately twice the number of seeds of the larger size peak: e.g. vrs1.a; and (D) seed size distribution similar to wild type and a reduced seed number per spike: e.g. lnt1.a. (E) Number of different row type mutants grouped based on the distribution in seed size as described in A-D.
Table 1.
Average seed number per spike and thousand grain weight (TGW) of row type mutants.
Fig 3.
Pleiotropic effects of mutations in different row type genes on tiller number cv. Bowman.
Plants were grown under outdoor conditions. (A) Photographs of one representative plant per genotype were taken at 92 DAS. No pictures were taken of int-m.85 mutants, because no tillering phenotype was visible at this point. (B) Tiller number was assessed two weeks after transplantation (50 days after sowing), at flag leaf stage, at anthesis stage and at full maturity. For all measurements n ≥ 10 plants, error bars ± SD. Letters a-f indicate significant differences (p≤ 0.05), determined with a one-way ANOVA using a Tukey HSD as post hoc test. Significant differences between the lines are calculated for each time point separately.
Fig 4.
Row type mutants cluster according to their trait phenotypes.
(A) Boxplots of tiller number at full maturity of all mutants in backgrounds Bowman (red), Bonus (blue) and Foma (green) tested under outdoor conditions (n ≥ 10 plants). Significant differences (p≤ 0.05) between the mutant and wild type parent were calculated using a one-way ANOVA with a Tukey HSD as post-hoc test. (B) Hierarchical cluster analysis (HCL) of the relative performance of different row type mutants compared to their respective backgrounds, Bowman (Bw), Bonus (Bon), Foma, Barke and Montcalm (Mont). All trait data used in the HCL analysis was obtained from plants grown outdoors. Relative performances were analyzed with a Pearson correlation and the mutants were clustered accordingly. The clustering shows one outgroup (green) and two main groups color-coded in black and purple.
Table 2.
Least mean square values for row type mutants under greenhouse and outdoor conditions.
Fig 5.
int-c mutants are high tillering only at early developmental stages.
Ten biological replicates per genotype were grown in a controlled greenhouse under long day (LD) conditions (16 h light). (A) Pictures of three representative plants per genotype at 32 DAE. (B) int-c.5 and int-f.19 in Bowman background together with Bowman. (C) The original int-c.5 mutant with its parent Bonus. The gray area indicates the time period when plants reached flag leaf stage. For all measurements n = 10 plants, error bars ± SD. * indicate significant differences between the mutants and the background (p ≤ 0.05) determined with a one-way ANOVA using a Tukey HSD as post hoc test.