A, kidney bean morphological characteristics: kidney bean's root system is more developed. Stem trailing, semi-trailing or dwarf. The first true leaves are simple, opposite; later true leaves are ternate compound, nearly heart-shaped. The pods are 10-20 cm long, straight or slightly curved in shape, round or oblate in cross-section, with a densely tomentose epidermis; the young pods are varying shades of green, yellow, purple-red (or mottled) and other colors, and yellowish-white to yellowish-brown at maturity. With the development of the pods, its back, ventral suture at the vascular bundles gradually developed, in the endocarp, the number of layers of thick-walled tissue gradually increased, thus reducing the quality of fresh food. Therefore, the young pods should be harvested at the right time. Each pod contains 4 to 8 seeds, seeds kidney-shaped, red, white, yellow, black and mottled and other colors; 1,000 grains weighing 0.3 to 0.7 kg. Second, bean curd morphological characteristics: annual twining, herbaceous vine or nearly erect herbs, sometimes apical twining. Stem nearly glabrous. Leaves pinnately compound with 3 leaflets; stipules lanceolate, ca. 1 cm, decurrent into a short spur where inserted, wired; leaflets ovate-rhombic, 5-15 cm long, 4-6 cm wide, apex acute, margin entire or subentire, sometimes lavender, glabrous. Racemes axillary, long pedicellate; flowers 2-6 clustered at tip of inflorescence, often with fleshy dense glands between pedicels; calyx light green, campanulate, 6-10 mm long, cleft teeth lanceolate. Corolla yellowish-white and slightly greenish purple, ca. 2 cm, all petals petiolate, flag petal compressed round, ca. 2 cm wide, apical part slightly concave, base slightly auriculate, pterygoid slightly triangular, keel petal slightly curved; ovary linear, hairy. Pods pendulous, erect or obliquely spreading, linear, 7.5-70 (90) cm long, 6-10 mm wide, slightly fleshy and swollen or firm, many-seeded; seeds long ellipsoid or terete or slightly reniform, 6-12 mm long, yellowish-white, dark red, or other colors. Fl. May-Aug.