Seed germination and seedling emergence in two populations of eastern dodder (Cuscuta monogyna Vahl.): evaluation of environmental factors and burial depth

To compare C. monogyna seed germination and the seedling emergence of two populations from Quchan and Bardaskan in Khorasan-e-Razavi-I province in north east of Iran, experiments were carried out. From the results, the highest germination percentages for Quchan (98%) and Bardaskan (97%) populations were observed at alternating 25/15 and 30/20 degrees C day/night temperatures, respectively. Germination percentage of both populations was 42-92% over a wide range of constant temperatures (10-35 degrees C). The NaCl concentration of 399.5 and 443.6 mM caused 50% inhibition of germination for Quchan and Bardaskan populations, respectively. The osmotic potential for 50% inhibition of germination was - 0.63 for Quchan and - 0.66 MPa for Bardaskan populations. The maximum emergence of Quchan (74%) and Bardaskan (80%) populations were recorded in the seeds placed at 0.5 cm with emergence failure at 5 cm soil depth. In another experiment in which seeds were after-ripened at different depths of soil in the field, seed germination was lower on the soil surface and 20 cm soil depth compared to 2, 5, 10 and 15 cm depth; and the highest seed emergence in the field was observed at 5 cm soil depth, 270 days after seed burial. The information of this study would be useful for determining the potential of this parasitic species to spread to new areas and arrange management strategies in different environmental conditions.

Automated summary

This study investigates the seed germination and seedling emergence of two C. monogyna populations in northeast Iran, and finds that temperature, salt concentration, and soil depth have significant effects on their growth.