V.K. GUPTA, I.M. SHARMA and. “Physiology of Apple Rootstock Susceptibility to Pythium Ultimum”. Indian Phytopathology 45, no. 4 (January 12, 2002): 439–443. Accessed June 25, 2026. https://epubs.icar.org.in/index.php/IPPJ/article/view/21735.