Allelopathic effects of Artemisia sieberi Besser on three important species (Agropyron desertorum, Agropyron elongatum and Atriplex canescens) in range improvement

Allelopathy is interaction effects of plants on each other through extracted chemical compounds. This phenomenon that has not been considered in range improvement is of important concerns in rehabilitation of rangelands. In this study, we tested allelophatic effects of Artemisia sieberi on germination percentage, stem fresh weight and root fresh weight of three species (Agropyron desertorum, Agropyron elongatum and Atriplex canescens) that are widely used in range improvement. Powder of Artemisia sieberi (stem, leaf and root) collected from natural habitats in flowering stage (end of Novambr) was mixed with different concentration levels (0%, 0/1 %, 1% and 10 %) in four replicetions and was planted in sand under laboratory condition based on completly rondom design. After putting 25 live seeds of the mentioned species in each pot, three variables as germination percentage, stem fresh weight and root fresh weight were measured and then ANOVA and Duncan's multiple range tests were applied to analyze the data in SPSS software. According to the results decrease rate of germination percentage in comparison to control treatment were as follows: in Agropyron desertorum 60 and 83% from 1 and 10 % leaf concenterations respetively, in Agropyron elongatum 84/2% from 10% leaf concentration and in Atriplex canescens 83/3 and 88/9% from 1 and 10% all tissues concentrations respectively. Also our finding showed that stem weight of Agropyron elongatum was decreased to 48 and 94/5%, respectively in 1 and 10 % of leaf tissue and root weight of Atriplex canescens was decreased to 82/2 and 88/1% in 1 and 10 % of all tissues in comparison to control treatment. According to results of the study under laboratory condition, rehabitating of Artemisia sieberi sites through using the mentioned species probably will not be successful.