Environmental factors on seed germination and seedling emergence of Phleum paniculatum Huds.

Abstract

Phleum paniculatum Huds., commonly known as British timothy, is an increasingly serious weed in wheat field of China. However, the biology of its seed germination and seedling emergence remain unclear. In the present study, the effects of environmental factors on seed germination and seedling emergence of P. paniculatum were explored. Phleum paniculatum seeds had a shallow dormancy (20-30 d) when stored at room temperature (25 ± 5 °C). Seeds could germinate at constant temperatures between 10 and 25 °C, except for 5 or 30 °C. Light was not essential for seed germination, and pH values from 4 to 10 did not inhibit germination. Seeds were moderately adaptable to water potential and NaCl concentration, and germination rates would be decreased 50% when water potential was -0.4 MPa or NaCl concentration was 130 mM. Increased soil burial depth decreased the seedling emergence, and no seeds emerged when the burial depth was more than 4 cm. Taken together, our results provide useful information of the germination and emergence of P. paniculatum seed, and strategies such as proper drainage systems managed and deep plowing are recommended to limit its detrimental effects on agricultural production.

Short-Term Responses to Salinity of Soybean and Chenopodium album Grown in Single and Mixed-Species Hydroponic Systems

“…This hypothesis is plausible considering that the salt-sensitive soybean plants contained less K + in their leaves, but no K + losses were evident due to NaCl. In addition, the TF for K + was always higher in C. album than in soybean, regardless of salinity, which suggests the better ability of C. album to control long-distance K + transport, either by more efficient xylem loading and delivery to the shoot or minimizing the extent of K + recirculation in the phloem [39]. Unlike C. album, soybean plants accumulated Na + equally between roots and leaves, while K + was preferentially retained in the roots.…”

“…In our study, C. album displayed a greater capacity of Na + accumulation and root-to-shoot delivery than soybean, which justified the two-fold-higher Na + /K + ratios in its tissues, while K + accumulation in leaves was conversely reduced by NaCl. K + loss from plants is a common phenomenon under salinity stress, and the capacity of plants to counteract salt-induced harms depends on K + availability and K + retention in tissues [39]. K + losses, however, are generally more pronounced in salt-sensitive than tolerant plant varieties [39,40].…”

“…K + loss from plants is a common phenomenon under salinity stress, and the capacity of plants to counteract salt-induced harms depends on K + availability and K + retention in tissues [39]. K + losses, however, are generally more pronounced in salt-sensitive than tolerant plant varieties [39,40]. Thereby, our results seem to be at odds with the current literature regarding C. album, but it must be noted that K + content was very high in the weed not treated with NaCl.…”

Effect of transplanting and direct sowing on productive properties and earliness of sweet corn

“…However, the direct sowing variants had significantly more missing plants, which suggests that these variants were under abiotic stresses. During the first year, excessive rain at the beginning of the growing season caused abiotic stress -that is, created soil crusts, which cause problems such as seedling emergence reduction (Amezketa et al, 2003;Wu et al, 2018). The main reason for a large number of missing plants among the direct sowing variants in the second year was low temperature.…”

Weed Seed Dormancy: The Ecophysiology and Survival Strategies

“…Seeds were moderately adaptable to water potential and NaCl concentration, and germination rates decreased by 50% when water potential was −0.4 MPa or NaCl concentration was 130 mM. Increased soil burial depth decreased the seedling emergence, and no seeds emerged at depth more than 4 cm [66].…”