Fig. 2.

GWAS for cucumber powdery mildew resistance. Phenotypic variations in powdery mildew resistance based on the disease index among the India, North America, Eurasia, and East Asia groups over the following three cropping seasons: fall 2022 (A), winter 2022 (B), and spring 2023 (C). Each black dot represents the average disease index of a cucumber accession. Student’s t-test was used to calculate the P value. D Manhattan plot for the GWAS results using fall 2022 data. E Manhattan plot for the GWAS results using winter 2022 data. F Manhattan plot for the GWAS results using spring 2023 data. G Manhattan plot for the GWAS results using the BLUP (best linear unbiased prediction) values; H quantile–quantile (Q-Q) plot for the GWAS results using fall 2022 data. I Q-Q plot for the GWAS results using winter 2022 data. J Q-Q plot for the GWAS results using spring 2023 data. K Q-Q plot for the GWAS results using the BLUP (best linear unbiased prediction) values. Red dashed lines in the Manhattan plots indicate the significance threshold (− log₁₀ P = 6.29). Black dots in the Q-Q plots represent the distribution of P values