Responses Of Plant Seedlings To Exogenous Salicylic Acid

Taking nine kinds of plants as experiment materials, this paper studied the effect of salicylic acid on plant seedlings through two different methods such as radicle pour and foliar spray. Some morphyological characters of seedlings such as plant height and root length were measured after treatment. The purpose of measured morphyological characters was to explore different sensitive degree of plants to SA, and screened sensitive plant to SA. Some physiological indexes such as chloropyll content and root activity of lettuce which was an sensitive plant to SA were measured to analyze physiological effect of SA. Our study had important practical significance. The purpose was provided for instruction of the use of SA in agriculture, and increased production of plant seedlings and improved crops, environmental security. Results were as follows:1.The results showed that the sensitivity differences of nine kinds of plants to SA were obvious through radicle pour. Monocotyledon plants such as wheat, corn and perrenial ryegrass,discotyledon plants such as soybean and cucumber were insensitive plants to SA. Cabbage and carrot were inhibitory plants to SA. Seedlings were restrained after different concentrations of SA treatments. Lettuce and tomato were sensitive plants to SA. Lettuce and tomato seedlings were restrained at higher concentration of SA, and were promoted at lower concentration of SA. After2mg/L SA treatmet, lettuce’s chloropyll content was increased, root activity, soluble protein content and seedlings growth were accelerated. The quality of lettuce seedlings was also improved.2. The results showed that the sensitivity differences of nine kinds of plants to SA were obvious through foliar spray. Monocotyledon plants such as corn and perrenial ryegrass, discotyledon plants such as soybean and cucumber were insensitive plants to SA. Tomato was inhibitory plant to SA, seedlings were restrained after different concentrations of SA treatments. Wheat, lettuce and tomato were sensitive plants to SA, seedlings were restrained at higher concentration of SA, and were promoted at lower concentration of SA. After25mg/L SA treatmet, lettuce’s chloropyll content was increased, root activity and seedings growth were accelerated. The quality of lettuce seedlings was also improved.