Semente de Salsola kali sobre papel milimetrado (cada quadrado com 1 mm de lado).
Seed of common saltwort (Salsola kali L., family Chenopodiaceae) surrounded by white mustard seeds (Sinapis alba L., family Brassicaceae)
Seed of common saltwort (Salsola kali L., family Chenopodiaceae) surrounded by white mustard seeds (Sinapis alba L., family Brassicaceae)
Seed of common saltwort (Salsola kali L., family Chenopodiaceae) surrounded by white mustard seeds (Sinapis alba L., family Brassicaceae)
Seeds of Salsola kali L. (common saltwort, prickly Russian thistle, prickly saltwort, Russian thistle, tumbleweed), family Chenopodiaceae, were intercepted in samples of white mustard (Sinapis alba L., family Brassicaceae), imported from Canada, in the last week of May, 2020. Common saltwort is an invasive species listed as Absent Quarantine Pest (PQA) on IN 39/2018. The identification was based on the morphological traits and the sequence of the Rbcl gene (primers rbcL 1F and rbcL 1352R). The sequence of 1206 nucleotides has 100% coverage and 99,83% of identity to the species Salsola kali, accession HM850332.1 of GenBank.
Fruit contains a single seed and has 5 wings - one from the back of each sepal. When the plant is mature it breaks off at the ground forming “tumbleweeds” that are tossed by the wind, scattering seeds. A single plant can produce 100 - 200,000 seeds (Morisawa, 2020).
The small, winged seed, retained in the leaf axils until after plant death, contains no endosperm tissue, but is instead comprised of a spirally-coiled, complete embryo already containing some chlorophyll (USDA, 2020).
In 1873, common saltwort was brought to the U.S. in contaminated flax seed (Morisawa, 2020).
White mustard seeds are hard round seeds, usually around 1.0 to 1.5 mm in diameter, with a color ranging from beige or yellow to light brown.
See the appearance of the adult plant: Russian Thistle (Salsola kali)
Literature:
Morisawa, TunyaLee. BugWoodWiki. Salsola kali. Available at: https://wiki.bugwood.org/Salsola_kali. Accessed on: June 15, 2020.
USDA. Salsola kali. Fire Effects Information System (FEIS). Available at: https://www.fs.fed.us/database/feis/plants/forb/salkal/all.html. Accessed on: June 15, 2020.
*******
How to cite: Gomes, P. S. C. F.; Rosado, J. P. Interception of seeds of an invasive quarantine plant for Brazil. Agriporticus. Disponível em: <http://www.agronomicabr.com.br/agriporticus/detalhe.aspx?id=910>. Acesso em: 15 jun.2020. (Atualize a data de acesso.)