Abstract
The outbreak of leaf and panicle blast caused by Pyricularia oryzae decreased to 25% (in greenhouse) and 50% (in paddy field) on rice plants by soaking seeds in DL-alanine dodecylester hydrochloride solution (500ppm). The second and the third generation of the rice plant retained this chemically induced resistance to the disease. The blast severity reduced to 39% in greenhouse test and 48% in field test (2nd generation), and 28% in greenhouse test (3rd generation). When the chemical treatment was repeated on alternate generations of the rice seeds, the induced protection effect of DL-alanine dodecylester hydrochloride reached at high levels of 75% (original), 61% (2nd generation), 87% (3rd generation) and 97% (4th generation) of blast-preventive values. On the rice plant whose blast resistance was chemically induced, conidia of P. oryzae germinated and formed appressoria, and then its hyphae penetrated into the host tissues. However, the invading hyphae were restrained in epidermal cells and adjoining cells without subsequent penetration.
