@article{Yadav2026, 
author = {Kirti A. Yadav and Yachana Jha and Haiam O. Elkatry and Heba I. Mohamed and Ahmed Mahmoud Ismail and Abdelrahman R. Ahmed},
title = {Morpho-Anatomical and Biochemical Defense Responses of Pigeon Pea Varieties to Phytophthora Blight},
year = {2026},
journal = {Phyton-International Journal of Experimental Botany},
volume = {95},
number = {1},
pages = {18},
keywords = {Defense-related enzymes, flavonoids, phenolics, protein, soluble sugars},
url = {https://www.sciopen.com/article/10.32604/phyton.2026.074570},
doi = {10.32604/phyton.2026.074570},
abstract = {Phytophthora blight is a devastating disease of pigeon pea (Cajanus cajan) that severely impacts plant growth and productivity. This study investigates the morphological, anatomical, and biochemical responses of a susceptible variety (ICPL 11260) and a resistant variety (IPAC-02) following infection by Phytophthora. Morphological analyses showed that infection caused a drastic reduction in root length, shoot length, leaf number, fresh weight, and dry weight in the susceptible ICPL 11260 variety, with reductions ranging from 0.5- to 2-fold compared to non-infected controls. Anatomical observations revealed pronounced cellular damage and mycelial invasion in infected ICPL 11260 plants by 30 days after infection, whereas infected IPAC-02 plants exhibited no fungal colonization. Biochemical analyses further demonstrated that the resistant IPAC-02 variety accumulated higher levels of total soluble sugars, proteins, phenols, and flavonoids, along with increased activities of defense-related enzymes (chitinase and β-1,3-glucanase), compared with the susceptible ICPL 11260. Under P. cajani stress, IPAC-02 maintained significantly elevated osmolyte concentrations (total sugars 153.7 mg g−1 FW; proteins 25.4 mg g−1 FW), secondary metabolites (phenols 51.7 mg g−1 FW; flavonoids 33.1 mg g−1 FW), and PR-enzyme activities (chitinase 11.4 U mg−1 protein; β-1,3-glucanase 9.1 U mg−1 protein). These responses support a lignification-mediated defense mechanism in IPAC-02 and highlight its potential value for breeding Phytophthora-resistant pigeon pea cultivars.}
}