How did witchweed get here?

The date and mode of witchweed’s arrival in the United States are not known (although the fact that it belongs to the Broomrape family may shed some light on its mode of transport). The first plants were discovered by a graduate student from India, who recognized the parasite from his country.

How does witchweed grow?

An annual plant, witchweed overwinters in the seed stage. Its seeds germinate in the presence of host root exudate, and develop haustoria which penetrate host root cells. Host root exudate contain strigolactones, signaling molecules that promote striga seed germination.

Which type of parasite witchweed is?

Root Parasitic Weeds. The most economically important root parasites are the witchweeds (Striga, Orobanchaceae).

How do you identify witchweed?

Red witchweed grows 10–40 cm tall and its leaves are arranged in opposite pairs along the stem. Leaves are 6–40 mm long and 1–4 mm wide, and have a tapered, pointed tip. Its flowers are 5–20 mm in diameter and are usually red, but can be white, yellow or pink.

Is Striga a root parasite?

Abstract. Striga are obligate root-parasitic plants of the major agricultural cereal crops, including millets, in tropical and semi-arid regions of Africa, Middle East, Asia, and Australia. Consequently, they cause severe to even complete losses in crop grain yield.

What is unique about witchweed?

Commonly known as ‘witchweed,’ the parasitic plant Striga hermonthica devastates crops in sub-Saharan Africa. Scientists have discovered a unique protein in Striga that helps sustain its high transpiration. In transpiration, water is carried through plants and evaporates from their leaves via stomata (breathing pores).

Are weeds An example of parasitism?

Parasitic weeds, such as Broomrapes (Phelipanche/Orobanche spp.), Striga, and some Cuscuta spp., represent the most extreme examples of parasitism on host plants.

Is Striga a partial root parasite?

Witch weed (Striga species) is well known partial root parasite of sugarcane Jawar, maize, cereals and millets in India. There are four species of Striga reports in the country on sugarcane, rice , sorghum and other millets.

Is Striga a parasite?

Striga are obligate root-parasitic plants of the major agricultural cereal crops, including millets, in tropical and semi-arid regions of Africa, Middle East, Asia, and Australia. Consequently, they cause severe to even complete losses in crop grain yield.

What are annual weeds?

Annual. Weed species that completes its life cycle (seed to seed) within one growing season or one calendar year. redroot pigweed, kochia. Summer Annual. Summer annual weeds are a subcategory of annual weeds.