Seed Germination Ecology of Giant Ragweed (Ambrosia trifida) in Korea

Farrukh  Ruziev1   In Kon Park2   Mirjalol Umurzokov1   Botir  Khaitov1   Aung Bo Bo1   Aung Bo Bo1   Wei Qiang Jia1   Le Thi  Hien1   Jung Sup  Choi3,*   Kee Woong  Park1,*   

1Department of Crop Science, Chungnam National University, Daejeon 34134, Korea
2Syngenta Korea Jincheon Station, Jincheon 33011, Korea
3Korea Research Institute of Chemical Technology, Daejeon 34114, Korea

Abstract

The effect of environmental factors on the growth of giant ragweed (Ambrosia trifida) was determined in this study. Seed germination and seedling emergence were evaluated under different photoperiods, constant temperature, and periods after harvesting and burial depths. Dry storage of freshly harvested seeds caused slow release of dormancy at 25℃. The maximum germination rate of >65% was observed 11 months after harvest. Different light periods showed no significant impact to seed germination. The lowest germination was observed under complete darkness, while the highest germination was under alternating dark/light conditions. Regarding the temperature, giant ragweed seeds were able to germinate well at low temperatures (5-15℃) compared to high temperatures (30-40℃). The optimum temperature for germination was between 15 and 25℃ (>85%). Seedling emergence was initially increased up to 2 cm depth of burial, after which emergence declined sharply with increasing the burial depth up to 10 cm. There was no emergence beyond 10 cm depth of soil. The results indicated that giant ragweed seeds could germinate in cold months of spring regardless the light period. However, seeds need to overcome dormancy and be established superior levels of soil to have higher chance of propagation.

Figures & Tables

Fig. 1. Changes in germination rate of seeds after harvest. Seeds were stored at 25℃ until use for the experiment. The vertical bars represent the standard error of the mean.