Developmental characteristics of sporogenous hyphae: a new observation between Brassica juncea var. tumida and Albugo candida

Abstract Brassica juncea var . tumida (tumorous stem mustard) is widely cultivated as a feature vegetable in Ningbo, Zhejiang Province, and used raw material for pickles China. White blister rust, caused by Albugo candida , has severe negative effects on tumorous mustard, resulting significant economic losses. In this study, hypha colonization extension, haustorial formation, the development process of sporogenous hyphae sporangia A. -infected tissues were studied using light transmission electron microscopy. Additionally, complex unique developmental was revealed. During infection, cytological ultrastructural characteristics similar to those cruciferous plants. development, an initially cylindrical with thin inner wall at apex developed from cell thick wall. At apical end hypha, electron-dense gathered, causing disintegration outer walls formation new walls. With clavate deep constriction occurred its subapex, which septum produced primary sporangium separated hypha. Both layers took part sporangial but not related septum, providing direct evidence holoblastic sporangia. Furthermore, observation demonstrated that within later than their lateral walls, including degradation constricted around subsequent upper layers, confirming earlier observation. Therefore, study provided model chain.