Response of Datum innoxia Mill plants to Jasmonic Acid Application

Abstract

Two experiments were carried out during the 1994/1995 and 1995/1996 seasons to study the effect of Jasmonic acid on the growth, cholorophyll content, the levels of endogenous hormones, alkaloid content and the yield of Datura innoxia Mill plants. JA was applied at three levels of concentration, i.e. 200, 400 and 8OO ppm, and distilled water as a control group.
The results indicate that application of JA at different concentrations significantly decreased plant height, and increased the number of both leaves and branches as well as the dry weight of the different organs of Datura plants.
Plantss treated with JA showed a decrease in transpiration rate and total Chl a+b, with an increase in the concentration of the JA.
Results also showed that the alkaloid content of the seeds was higher than that of the different organs of Datura innoxia. Seed yield and alkaloid level, as well as the oil content, of the seeds were significantly increased by JA treatments. The effect was more pronounced wioth JA at 800 ppm during both seasons. On the other hand, JA treatments decreased growth promoters and increased growth inhibitors with an increasing concentration of JA.