Seed priming effects on germination and first growth of the medicinal plant Achillea millefolium L.

This study evaluated the effects of seed priming on germination and growth of A. millefolium by means of laboratory and greenhouse experiments conducted during 2018 in the Agricultural University of Athens. Treatments were GA3 (400 and 800 ppm), potassium nitrate (2% and 4%), polyethylene-glycol (soaking for 12 and 24h) besides an untreated control. Experiment in Petri dishes revealed that GA3 at 400 ppm, potassium nitrate (at concentration 2 and 4%) and PEG significantly increased germination percentage of A. millefolium, while germination rate was also significantly improved as a result of all seed priming techniques. In addition, due to the soil experiment, seedling emergence was significantly increased by GA3 at 400 ppm, potassium nitrate (at both concentrations) and PEG compared with the untreated seeds. Dry biomass of the young seedlings was significantly enhanced by means of GA3 (at 400 and 800 ppm), KNO3 (4%) and PEG for 24 h, indicating the potential effect of seed priming on first growth as well. The results of the present study revealed the significant positive effects of seed priming on A. millefolium seed germination, seedling emergence and early growth

First Report of Amaranthus palmeri S. Wats. in Cotton, Maize and Sorghum in Greece and Problems with Its Management

Amaranthus palmeri S. Wats., or commonly Palmer amaranth, is an invasive plant species that has invaded many countries worldwide and causes significant yield losses to annual spring crops. Palmer amaranth biotypes were detected in maize and sorghum fields in Western Greece and cotton fields in Central Greece in 2020. The infestations were recorded both inside the crops and in the margins of the fields, indicating that Palmer amaranth could be characterized as an invasive weed for these regions and, thus, must be urgently managed. Four biotypes were screened for resistance to 2,4-D and nicosulfuron by using NDVI, canopy cover, photochemical efficiency, plant height and fresh weight values. All biotypes showed resistance to nicosulfuron. Resistance cases to important herbicides (i.e., ALS and synthetic auxins) in spring crops, such as maize and cotton, indicate that management could become even more challenging if farmers do not adopt integrated strategies and tools to manage this weed. The eradication of Palmer amaranth plants is imperative, since it has yet to be dispersed in several agricultural areas of Greece. Palmer amaranth is recommended to be enlisted as quarantine pest for regulation in Greece