Effect of harvesting time on quantity and quality characteristics of common plantain (Plantago major L.) seeds

Harvesting time is one of the most important factors affecting the seed quality. In order to determine the effects of harvesting time on quantity and quality of plantago major seeds, two experiments were carried out in the Ferdowsi University of Mashhad in 2014. In the first experiment six plantain ecotypes (Birjand, Ghaen, Torbat Hydarieh, Mashhad, Kalat and Bojnord) grown in the field and plant spikes were harvested in six stages with 15 days interval (15, 30, 45, 60, 75 and 90 days after 50% pollination), then germination of harvested seed was tested in the laboratory. Number of spike per plant and its length after 50% of pollination increased and reached to the maximum in 75 and 60 days after that, respectively. Kalat ecotype had the fewest and the shortest spikes, while Birjand and Bojnoord ecotypes produced the longest spikes. The maximum seed weight per spike for Kalat and Bojnoord ecotypes was obtained at 90 days after 50% pollination, while in the other ecotypes it was observed at 75 days after that. The highest germination, speed germination length and weight vigor index in Ghaen ecotype was observed at 75 days after 50% pollination, while in the Torbat Hydarieh ecotype they were observed at 45 days after 50% pollination. In Ghaen, Torbat Hydarieh and Mashhad ecotypes delaying in harvest time of 75 days after 50% pollination causes seed losses and reduction in seed germination.