Fig. 3. SWEET^ko knockout mutants as diagnostic tools.

a, Phenotypes of sweet13-1 and sweet13-2 knockout mutants relative to Kitaake controls at the mature stage. Scale bar, 10 cm. b, Relative mRNA levels of SWEET13 in flag leaf blades. Samples were harvested at 12:00 (mean ± s.e.m., n = 3 biological replicates with mRNA levels normalized to rice Ubiquitin1 levels; repeated independently three times with similar results). Center lines show medians; box limits indicate the 25th and 75th percentiles as determined by R software; and whiskers extend 1.5 times the interquartile range from the 25th and 75th percentiles. c, One-thousand-grain weight of greenhouse-grown Kitaake, sweet13-1 and sweet13-2 (mean ± s.e.m.; n = 4 biological replicates). The experiment was repeated at least three independent times with similar results. Center lines show medians; box limits indicate the 25th and 75th percentiles as determined by R software; and whiskers extend 1.5 times the interquartile range from the 25th and 75th percentiles. No significant differences (P = 0.051 for sweet13-1 and P = 0.758 for sweet13-2) were identified by Student’s t-test. d, Phenotypes of wild type and the sweet13;sweet14 double knockout grown in the greenhouse. No significant differences were identified. e, Length of lesions at 14 days after inoculation (DAI) caused by ME2 (negative control), PXO99 (positive control) and AXO1947 on single-, double- and triple-knockout (sweet11, sweet13 and sweet14) mutants relative to Kitaake wild type (mean ± s.e.m.; n = 10 inoculated leaves). The experiment was independently repeated twice with similar results. The difference observed for AXO1947 virulence between sweet14 and sweet11;14 in a single experiment was not significant when compared over a larger number of experiments (Supplementary Fig. 14).