Effect of Different Treatments on Improving Seed Germination Characteristics of Astragalus adscendens and Astragalus podolobus

Abstract

Nowadays, in many rangelands, due to over grazing, and problems that some plants<br />have in germination, the rate of forage production is greatly reduced. So to take advantages of<br />the benefits of such plants, it is necessary to identify and remove barriers of germination and<br />establishment of suitable plants. The present study was designed to investigate different<br />treatments of breaking dormancy and stimulating seed germination of Astragalus adscendens<br />and Astragalus podolobus and offer the most effective treatment to enhance germination and<br />growth rate. The experiment was conducted using Completely Randomized Design (CRD)<br />with four replications. Treatments included hot water for 5 minute, 30% hydrogen peroxide for<br />5 minute, 98% sulfuric acid for 5 minute and chilling at 4°C for 10 days. Data were collected<br />for seed germination percentage, Germination Rate (GR) and Mean Germination Time<br />(MGT). Based on the results, treatment with 98% sulfuric acid for 5 min for A. adscendens<br />and hot water for 5 min for A. podolobus were the best treatments to break dormancy and<br />stimulate seed germination, so that the germination percentage increased from 44% to 82% in<br />A. adscendens and from 28% to 62% in A. podolobus. In A. adscendens 98% sulfuric acid<br />reduced the amount of MGT from 8 days for control treatment to 5 days. In A. podolobus hot<br />water treatment was more effective on MGT reduction and reduced it from 7 to 5 days.<br />Although sulfuric acid had the highest effect in breaking dormancy, but its application in a<br />vast scale is not easy, therefore the hot water was suggested as the substitution treatment.