Nyasha Chatambudza

Business Reporter

AN Agritex agronomist has warned farmers to be on the lookout for the witch weed also known as striga, as it might affect their winter crop.

In an interview, an Agritex agronomist Mr Davison Masendeke said the weed has in the past destroyed huge acres of crop.

“Witch weed is a serious threat to the livelihood of most crops. Farmers should be on the lookout as it can significantly reduce yields in some cases wiping out the entire crop,” he said.

He said that the parasitic weed germinates on the roots of the host plant in the process                      suffocating the crop.

“Germination is triggered by the presence of the host plant. Damage starts when the weed is still under ground before the parasite emerges hence can affect up to 60 percent to 100 percent of the crop,” he said

Mr Masendeke said most host plants commonly affected by the witch weed are maize, sorghum, pearl millet and pulses mostly cow peas.

“Most plants which are affected are those which are grown on a yearly basis and make up the staple crops of this country, crops such as maize, sorghum and pearl millet. They (farmers) should practice good agronomic skills. They should plant early so that they provide nutrients, inorganic fertilisers especially nitrogen based fertilisers so that there is vigorous crop growth enough food for the crop to survive under attack.”

He said that farmers should conserve moisture so the crop has enough moisture to strive and never allow the weed to flower.

“The weed should not be allowed to flower by uprooting and using herbicides such as 2-4 D,” he said.

Mr Masendeke said farmers can force the weed to commit suicide by early planting and then apply methods similar to green manuring.

“Farmers should plant populations of the host plant early in the season to trigger massive germination of the weed, periodically check crop roots for any traces of the weed and if satisfied that there has been good germination plough down the crop. They can also plant early maturing crops like beans, cowpeas,        pearl millet and if done in two to three successive seasons it will drastically reduce seed reserves of the parasite.”

He said symptoms of the weed attack include stunting, wilting and chlorises of the host plant almost  similar to those caused by severe drought damage, nutrient deficiency and vascular diseases.