Brassica rapa L.
Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)
the most likely form found as a table grape
contaminant is probably the weedy ssp. sylvestris (L.) Janchen
Pertinent Common Names (particularly those used in California; go to GRIN for other common names)
wild turnip, field mustard
Primary Disseminule Type
Description (diagnostics are in brown)
Fruit a dehiscent silique, terete, linear, constricted between seeds, glabrous, (2)3–8(11) cm long x (1.5)2–2.5(5 mm) wide including the apical beak (=terminal segment) which is 8–22 mm long, each of the 2 valvular segments with 8–15 seeds.
Seed ovoid (smooth to angular) to nearly globose, (1.1)1.5–2(3) mm diameter, with or without a distinct ridge or groove representing the position of the radicle. Surface glabrous, yellow or gray to reddish-brown or black, sometimes mottled, finely reticulated, interspaces of mature seeds typically pitted, interspaces and reticulum stigmaticose.
Hilar region a flush or slightly raised white linear ridge (not always present on yellow seeds) within a darker-colored (brown to black) circular area that is slightly convex.
Embryo bent, cotyledons conduplicate, endosperm lacking.
Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)
AUQP, NZBORIC, NZBPI