**Appendix A**

**Figure A1.** Experimental set-up for the DS and WS experiment. WS—wet season, DS—dry season.

**Figure A2.** Weather data for the DS and WS experiment measured at the IRRI weather station as average values per day. Radiation (**A**), sunshine duration (**B**), rainfall (**C**), relative humidity (**D**), maximal temperature Tmax (**E**), minimal temperature Tmin (**F**). Broken lines represent a trend line for the respective data set. DAT—days after transplanting. Average values for all weather parameters were significantly different (*p* < 0.05) between WS and DS.

**Figure A3.** Yield reduction under HNT in the WS (**A**) and DS (**B**). Cultivars are sorted from highest to lowest yield reduction.

**Figure A4.** Biomass (**A**, **B**), spikelets per m<sup>2</sup> (**C**, **D**), and spikelets per panicle (**E**, **F**) of eight rice cultivars in response to HNT stress for the WS (**A**, **C**, **E**) and DS (**B**, **D**, **F**). For the WS, variance is displayed as range between means of two replicates with 12 plants each; for the DS, the standard error of the mean of five replicates with 12 plants each is shown. Cultivars are sorted alphabetically within the respective *O. sativa* subspecies *indica* (1-4) and *japonica* (5–8). Significance levels were only calculated for the DS due to the insufficient replicate number in the WS and are indicated by asterisks: 0.001 < \*\*\*; 0.001 > \*\* < 0.01; 0.01 > \* < 0.05.

**Figure A5.** Log2 fold changes in significantly changed metabolite pools under HNT compared to under control conditions in panicles for the DS (**A**). For comparison, the same metabolites are shown for the WS (**B**) independent of a significant change. For the DS, only metabolites that showed a significant change in at least three out of eight cultivars are displayed in (**A**). The level of significance is indicated by asterisks (\* *p* < 0.05; \*\* *p* < 0.01; \*\*\* *p* < 0.001), and the log2 fold difference is indicated by the color code. Blue indicates a lower metabolite level compared to under the control condition, and red, a higher level. Cultivars were sorted alphabetically within the respective *O. sativa* subspecies *indica* (1–4) and *japonica* (5–8).

**Figure A6.** Log2 fold changes in significantly changed metabolite pools under HNT compared to under control conditions in panicles for the WS (**A**). For comparison, the same metabolites are shown for the DS (**B**) independent of a significant change. For the WS (**A**), only metabolites that showed a significant change in at least three out of eight cultivars are displayed. The level of significance is indicated by asterisks (\* *p* < 0.05; \*\* *p* < 0.01; \*\*\* *p* < 0.001), and the log2 fold difference is indicated by the color code. Blue indicates a lower metabolite level compared to under the control condition, and red, a higher level. Cultivars were sorted alphabetically within the respective *O. sativa* subspecies *indica* (1–4) and *japonica* (5–8).
