Allelopathy Effects of Trifolium alexandrium L. on Germination and Nutrient Uptake in Medicinal Plant Peganum harmala L.

The present study focused on effects of Trifolium alexandrium L. extract (۰.۰۰۲, ۰.۰۰۴ and control) which is a fast-growing plant on germination, growth and nutrients uptake of medicinal plant Peganum harmala L. Results revealed that T. alexandrium extract had significant (P<۰.۰۱).effect on seed germination of P. harmala The maximum (۵۴%) and minimum (۲۸%) seed germination were observed at ۰.۰۰۲ and ۰.۰۰۴ treatments, respectively. The highest radical (۱۱.۲۷ mm) and pedicle (۱۹.۱۰ mm) lengths were obtained in the ۰.۰۰۲ treatment, and the minimum radical (۴.۰۵ mm) and pedicle (۹.۴۰ mm) length were related to ۰.۰۰۴ treatment. With increased extract concentration, dry weight of P. harmala decreased. Also, the maximum (۱۵.۷۹ mg g-۱ fresh weight) and minimum (۶.۹۴ mg g-۱ fresh weight) chlorophyll contents of P. harmala were observed at ۰.۰۰۲ and control treatments, respectively. The highest (۶.۰۸ mg g-۱ fresh weight) and lowest (۴.۳۴ mg g-۱ fresh weight) chlorophyll b and also the highest (۴.۸۹ mg g-۱ fresh weight) and lowest (۲.۶۹ mg g-۱ fresh weight) carotenoids contents were obtained in ۰.۰۰۲ and ۰.۰۰۴ treatments, respectively. Furthermore, T. alexandrinum extract had significant effects on the uptake of N, P, K, Zn and Mn. The maximum amount of N uptake (۳.۷۷%) was observed in the extract concentration of ۰.۰۰۲. The maximum (۰.۳%) and minimum (۰.۲۱%) P uptake was observed in the control and ۰.۰۰۴ treatments, respectively. With increasing the extract concentration K uptake was decreased. The maximum (۰.۲۲ and ۰.۱۹%, respectively) and minimum (۰.۱۴ and ۰.۱۵%, respectively) Zn and Mn uptake were observed in the control and ۰.۰۰۴ treatments, respectively. In general, results showed that high concentration of T. alexandrium extract has deterrent effects on seed germination and growth of P. harmala, so that lower concentration of extract, showed positive effect on seed germination plant growth.

Keywords:

Plant growth , Photosynthesis , Peganum harmala L , Trifolium alexandrium L