At a time when increasing agricultural produce and improving agricultural yield is given paramount importance, our fruits and vegetables have been under siege by one more pest. This is the adult Bagrada bug, which goes after winter crops such as cabbage, kale, broccoli, arugula, cauliflower and radish. It sucks the sap out of tender leaves, leaving puncture marks and a stippled or wilted leaf. The Bagrada bug, Bagrada hilaris, also called the painted bug, is a stink bug that attacks various vegetable crops and weedy mustards and is particularly devastating to young seedlings and leafy greens. Native to northern Africa, the Bagrada turned up in the United States in Los Angeles in the June of 2008.
The Bagrada sucks the juices from the bite and leaves a toxic sort of saliva at the scene of the crime that can cause the plant to die even after the bug has left. Further, even if the Bagrada’s sap-sucking ways aren’t fatal, they can cause extensive wilting and yellowing, and stunt the growth of their hosts. These vile pests feed by inserting piercing mouth parts into plant tissues, which creates starburst-shaped lesions on leaves and stems. Continued feeding causes leaf scorch, stunting, blind terminals and forked or multiple heads on broccoli, cauliflower and cabbage. Initial damage to leaves is observed along the margins as stippling, or small tan or white dots left where the leaves were pierced by insect mouthparts and the juices sucked out. If feeding pressure is severe enough, the stippled areas merge and the leaf eventually wilts and dies.
Adding to their nastiness is the fact that Bagradas are capable of flying up wind to find new plants to feast on, and that they lay most of their eggs in the soil, thus making traditional predators worthless as possible controls. The infestation may be widespread covering the stems and leaves of the tree, leaving faecal droppings on the backsides of leaves. Local growers estimated that in some fields Bagrada bugs caused as much as 35% yield loss in green cabbage and greater than 35% yield loss in red cabbage! In broccoli, damage estimates by growers have ranged from 15‐30% losses due to these insects.
The severity of this issue can be better understood by reading the below article.
Pesky Bagrada bugs expand northward in California
Bagrada bugs, which were first confirmed in California six years ago, have been steadily expanding their range to the east and north.
They now have been confirmed as far north as Yolo County and have taken up residence in counties stretching from Santa Clara and San Mateo west to Fresno and Inyo counties, according to a University of California news release.
The university has tracked the pest’s expansion using citizen scientists.
Bagrada bugs, which have also hit crops in Arizona’s Yuma Valley, prefer cruciferous vegetables, such as cabbage, kale, cauliflower, brussels sprouts and broccoli.
In home gardens, they also have been found on green beans, cantaloupe, corn, peppers, potatoes, tomatoes and sunflowers.
In addition, the bugs have been found on ornamentals, including sweet alyssum, stock and candytuft.
Adult Bagrada bugs are about the size of a watermelon seeds with black backs and white and orange markings.
Both adults and nymphs have piercing and sucking mouth parts. As they feed, they remove plant sap and cause dead spots plant leaves and stems where they feed.
Under severe infestations, especially with young transplants, the pest can stunt, deform and even kill plants.
Originally it was hoped that Northern California’s colder winter temperatures would help prevent their northerly march.
But bugs simply take up refuge in the top layer of soil around the crops and appear to survive.
The Bagrada bug lays most of its eggs in the soil, so natural predators such as wasps aren’t effective controls. Picking the bugs off plants by hand is not feasible because the infestations are so thick and sudden, with multiple generations occupying one plant at a time. Thus we need a solution which would effectively keep the Bagrada population in check, keeping them away from our vegetables and crops, while at the same time not having any negative impact on the vegetables or the environment.
C Tech Corporation offers a product called Termirepel™, which is a non-toxic, non-hazardous, environmentally safe insect repellent. It can repel more than 500 species of insects on account of it being a broad spectrum anti-insect repellent. The most striking feature of Termirepel™ is that it neither kills the target species, nor the non-target species. It will simply keep the insects away from the application. This product is available in masterbatch and lacquer form, and as a liquid solution. Termirepel™ can be added in mulches or incorporated in agricultural bags and films, which could be used to keep our vegetables and fruits safe and guarded against the pesky Bagrada bugs!