عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The study was conducted to investigate the effect of humic acid on germination indexes and photosynthesis pigments of medicinal plant Plantago ovata Forssk in a completely randomized design. Experimental treatments comprised the following dosage 0, 15, 30 g Li-1. Results relived that humic acid had significantly effect on germination rate and seed vigor index. The highest and the lowest germination rate, the highest and the lowest seed vigor index were measured in dose of 30 gLi-1 and the control treatment respectively, while humic acid was not effective on germination percentage and mean of germination time. Humic acid showed significant effect on radical length and dry weight (p<1%), length and pedicel dry weight, and allometric coefficient (p<5%), however seedlings were not different significantly in radical and pedical fresh weight in response to humic acid. The highest and the lowest radical length, the highest and the lowest radical dry weight, the highest and the lowest pedicel dry weight were measured in dose of 30 gLi-1 and the control treatment respectively. The highest pedicel length was related to dose of 15 gLi-1 and the lowest was observed in the control treatment. The highest allometric coefficient was obtained in 30 gLi-1 dosage. The best effect on chlorophyll pigments was obtained in dose of 30 gLi-1. The highest and lowest chlorophyll a, chlorophyll b and total chlorophyll were observed in 30 and 0 gLi-1 respectively. In general, results showed that humic acid in dose of 30 gLi-1 was effective to enhancing quality of P. ovata Forssk.