The role of seed coat in the germination and early stages of growth of bean (Phaseolus vulgaris L.) in the presence of chickweed (Stellaria media (L.) Vill.)

The aim of the study was to determine the role of the seed coat in the presence of aqueous extracts from Stellaria media (L.) Vill. on germination and early growth stages of bean seeds Phaseolus vulgaris L. Dry shoots of the chickweed aqueous extracts were prepared, with which the bean seeds with coat and without coat were treated. The control group was seeds watered only with distilled water. After 7 days of the experiment, seed germination parameters, seed germination rate (SE), seed vitality index (SVI), seedling growth inhibition index (IP), fresh and dry mass values and percentage water content were determined. The experiment showed the germination capacity of bean seeds was varied, in relation to seeds from the control. With increasing concentrations of extracts, a significant reduction in the seed germination rate was observed, both for those with seed coat and without seed coat. The seed vitality index increased only in seeds with coat, and decreased in each of the applied concentrations of extracts in seeds without seed coat. The seedling growth inhibition index reached negative values in both groups of seeds tested only at a concentration of 5%. In comparison to the control, IP was positive for seedlings watered with 15% extracts. For P. vulgaris seedlings grown on 5% of extracts the highest increase in the fresh mass was observed, in relation to the value of control mass. For seedlings grown from seeds with seed coat the diferences in the dry mass values primarily were noted. The percentage of water content in bean seedlings varied depending on the group of seeds studied and the concentration of allelopathic substances in the chickweed aqueous extracts. The examined indexes of seed germination and seedling growth showed that in the case of P. vulgaris seeds without seed coat. The role of seed coat in the germination and early stages of growth of bean (Phaseolus vulgaris L.) in the presence of chickweed (Stellaria media (L.) Vill.) were more sensitive to aqueous extracts from dry shoots of S. media. Compared to the control group, in low concentrations of allelopathic substances the seeds germinated similarly to the distilled water, and at higher concentrations, the seeds germination, the seedlings growth and fresh and dry mass values were inhibited.