Global climate change and invasive species are quickly becoming two of the most important problems in natural and human managed ecosystems. Conyza canadensis (L.) Cronq is one of the most invasive plants in the world, widespread in the European and Italian agricultural systems. Temperature and light have been known to influence weed seed germination, but little information exists about the effect of environmental factors on C. canadensis germination. The objective of this study was to determine the effect of temperature and light on C. canadensis germination. Seeds of C. canadensis were collected from naturally senescing plants in central Italy (September 2016) and stored in the dark at 4 °C. Fifty seeds were placed on a filter paper (moistened with 5 ml of deionized water) in 90-mm plastic Petri dishes that were put in a growth chamber at different light/ temperature conditions: eight constant temperatures (2.5, 5, 10, 15, 20, 25, 30, 40 °C) and three fluctuating temperatures (18/12, 23/17, 28/22 °C) in 12h/12h:light/dark; three fixed temperatures (15, 20, 25 °C) in complete darkness. All treatments were replicates thrice. Seed germinations were recorded daily until no more germinations were observed for at least 7 days. C. canadensis was able to germinate in a wide range of temperatures (Tbase = 6.7 and Tcutoff = 35.6 °C). The highest germination capacity was observed at 15 °C (light/dark); no differences were observed at 17/23 and 22/28 °C with respect to 20 and 25° C (light/dark), while germinations were significantly reduced at 12/18 °C and in darkness. The highest germination rate was observed at 25 °C (light/dark) and it was significantly reduced at 12/18 °C and in darkness. These results can help understand the potential for C. canadensis to spread into new environments and agro-ecosystems, as well as suggest new methods and strategies for its management.
Evaluation of light/temperature on the germination of Conyza canadensis (L.) Cronq. In central Italy
Pannacci E.
Writing – Original Draft Preparation
;Onofri A.
2018
Abstract
Global climate change and invasive species are quickly becoming two of the most important problems in natural and human managed ecosystems. Conyza canadensis (L.) Cronq is one of the most invasive plants in the world, widespread in the European and Italian agricultural systems. Temperature and light have been known to influence weed seed germination, but little information exists about the effect of environmental factors on C. canadensis germination. The objective of this study was to determine the effect of temperature and light on C. canadensis germination. Seeds of C. canadensis were collected from naturally senescing plants in central Italy (September 2016) and stored in the dark at 4 °C. Fifty seeds were placed on a filter paper (moistened with 5 ml of deionized water) in 90-mm plastic Petri dishes that were put in a growth chamber at different light/ temperature conditions: eight constant temperatures (2.5, 5, 10, 15, 20, 25, 30, 40 °C) and three fluctuating temperatures (18/12, 23/17, 28/22 °C) in 12h/12h:light/dark; three fixed temperatures (15, 20, 25 °C) in complete darkness. All treatments were replicates thrice. Seed germinations were recorded daily until no more germinations were observed for at least 7 days. C. canadensis was able to germinate in a wide range of temperatures (Tbase = 6.7 and Tcutoff = 35.6 °C). The highest germination capacity was observed at 15 °C (light/dark); no differences were observed at 17/23 and 22/28 °C with respect to 20 and 25° C (light/dark), while germinations were significantly reduced at 12/18 °C and in darkness. The highest germination rate was observed at 25 °C (light/dark) and it was significantly reduced at 12/18 °C and in darkness. These results can help understand the potential for C. canadensis to spread into new environments and agro-ecosystems, as well as suggest new methods and strategies for its management.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
