De novo genome assembly and annotation of P. major. (a) Morphological characteristics of P. major include seeds, seed pods, seedlings, and adult plants. Black scale: 2 mm; white scale: 4 cm. (b) Contact map of Hi-C-based intra-chromosomal interactions. (c) Genetic collinearity among six P. major chromosomes. (a) chromosome length; (b) gene density; (c) gene expression pattern in leaf; (d) gene expression pattern in root; (e) gene expression pattern in seed; (f) GC content; and (g) paralogous gene pairs.