Study on the quality evaluation of pigeon pea accessions

Pigeon pea (Cajanus cajan) is a legume species used for both medicine and food. This study compared 10 pigeon pea accessions with respect to leaf water content, active components in extracts, total flavonoids, polysaccharides, and external morphological characteristics and then analyzed the metabolic differences of 4 different accessions (3-QZ, 4-HK, 5-DH₃, and 6-DZ). There was abundant variation in morphological characters, with the variation coefficient ranging from 8.75% (hundred-seed weight) to 37.96% (number of branches). There were significant correlations (P < 0.05) between moisture content and leaf length, active components in extracts and pod length, leaf shape index and inflorescence axis length, inflorescence axis length and banner petal size, inflorescence axis length and pod width, pod length and hundred-seed weight, and pod width and hundred-seed weight. Total flavonoid content was significantly correlated with banner petal size, leaf length and width, leaf shape index, pod width, and hundred-seed weight ( P < 0.01), and there were significant differences with regard to active components ( P < 0.05). Four pigeon pea accessions were analyzed to determine their metabolite content, and 453 compounds were obtained, which included lipids, organic acids, terpenes, alkaloids, tannins, amino acids and their derivatives, phenolic acids, nucleotides and their derivatives, flavonoids, quinones, lignans, coumarins, and other compounds, of which flavonoids were the most dominant; there were significant differences among different accessions ( P < 0.05). This study provides a reference for the breeding of new varieties of pigeon pea and the analysis of active components of this plant.