Planta Daninha (2011) 29, 737-743

O.M. Yamashita, S.C. Guimarães and A.L. Cavenaghi (2011)
Germinação das sementes de Conyza canadensis e Conyza bonariensis em função da qualidade de luz
[Germination of Conyza canadensis and Conyza bonariensis seeds as a function of light quality]
Planta Daninha 29 (4), 737-743
Abstract: The weed species Conyza canadensis and C. bonariensis have been increasingly reported, given their capacity to develop under the no-tillage system (NTS). Light is necessary for germination of several weeds, and is considered a factor of seed dormancy break. Seed germination in NTS is affected by light wave length filtering by straw, which can directly influence that process. The aim of this work was to determine the effect of different light filters on seed germination of C. canadensis and C. bonariensis. An experiment was carried out in which the seeds of these species were placed to germinate on blotting paper moistened with distilled water, inside transparent gerboxes involved with blue, green, red, light red and transparent light filters, as well as black gerboxes (light absence). Seed germination was evaluated at 5 and 10 days after sowing and at the end of this period for 10 more days, with all the treatments being under the condition of white light (filter absence). The seeds of both species were significantly affected by wave length filtering, except for the red filter which provided superior germination, inferior only to transparent filter.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: Portuguese)
Full text of article

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
environment - cropping system/rotation

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Erigeron canadensis (weed)
	Erigeron bonariensis (weed)