Potential global distribution of Aleurocanthus woglumi considering climate change and irrigation

Model parameterisation The fitted parameter values for A. woglumi are given in Table 1, with an explanation of each parameter. Stress indices. Cold stress. There appear to be two cold stress mechanisms limiting the dis- tribution of A. woglumi: a lethal temperature sensitivity and a degree day energetic balance mechanism. Aleurocanthus woglumi does not survive exposure to temperatures below freezing [41] and there is no known physiological mechanism to allow overwintering of A. woglumi in cold climates. Accordingly, the lethal temperature cold stress threshold (TTCS) was set at 0˚C (average weekly minimum temperature < 0˚C) and the stress accumulation rate (THCS) at -0.01 week-1 (stress accumulates moderately quickly). The cold stress temperature threshold of 0˚C allows persistence in high altitude areas of Fars Province in Iran, which is consistent with the current distribution records, and limits the distribution range in northern areas where A. woglumi is not known to occur. The cold stress degree day threshold was set to 6˚C days per week, and the corresponding stress accumulation rate was set to -0.001 week-1. Under this mechanism, cold stress accumulates if there were fewer than 6 degree-days above DV0 (14˚C) and provided an appropriate fit to the observed distribution in North America, South Africa, and Asia. Table 1. CLIMEX model parameter values for Aleurocanthus woglumi. Parameter Description Value Moisture SM0 lower soil moisture threshold 0.1a SM1 lower optimum soil moisture 0.3 a SM2 upper optimum soil moisture 1.2 a

SM3 upper soil moisture threshold 2 a Temperature DV0 lower threshold 14˚C DV1 lower optimum temperature 26˚C DV2 upper optimum temperature 32˚C DV3 upper threshold 43˚C Cold stress TTCS cold stress temperature threshold 0˚C THCS temperature threshold stress accumulation rate -0.01 week-1 DTCS cold stress degree-day threshold 6˚C days DHCS degree-day cold stress accumulation rate -0.001 week-1 Heat stress TTHS heat stress temperature threshold 43˚C THHS temperature threshold stress accumulation rate 0.01 week-1 Dry stress SMDS soil moisture dry stress threshold 0.1 a HDS dry stress accumulation rate -0.05 week-1 Threshold Heat Sum PDD number of degree-days above DV0 needed to complete one generation 985˚C days Irrigation scenario 4.5 mm day-1, applied as top-up aExpressed as a proportion of soil moisture holding capacity, where 0 indicates oven dry and 1 the field capacity (saturation). https://doi.org/10.1371/journal.pone.0261626.t001 PLOS ONE Potential global distribution of Aleurocanthus woglumi PLOS ONE | https://doi.org/10.1371/journal.pone.0261626 December 20, 2021 5 / 18