The Bagrada bug, Bagrada hilaris A new pest of cole crops, the Bagrada bug (also known as the painted bug) has recently been found in Brassica crops (broccoflower, broccoli, cabbage, cauliflower and others) throughout the southwestern desert growing areas of Yuma, AZ and the Imperial and Coachella Valleys, CA. It is a new stink bug not common to this area. It was first found in June 2008 in Los Angeles Co. California, and is now widely distributed in LA and Orange Counties. Establishment of the bagrada bug in California is the first reported occurrence in the US. http://cisr.ucr.edu/bagrada_bug.html Distribution: The bagrada bug is a known pest of cole crops in Africa, Egypt, southern Asia and southern Europe (Malta and Italy). Until recently, the only known occurrence of this pest in the US was from Southern California. http://cisr.ucr.edu/bagrada_bug.html The pest has now extended it’s host range into Riverside and Imperial counties of California, and southwestern Arizona. It is likely in northern Mexico, but has not been reported to date. We recently observed serious damage to seedling cole crops being grown under organic prodtiduction in the ChllCoachella VllValley. J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona This stink bug species can readily fly. We observed occasional short flights of 10-15 feet within the field. Note the hemelytra forewings and the triangular scutellum common with stinkbugs. It was common to see bagrada bugs walking on the bed surface and it is not unusual to find mating pairs walking on plants and soil surfaces. This pair was found on purslane, but we observed no feeding signs or damage on the purslane. J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona Although mating was obviously occurring, we did not observe any egg masses on the plants . Based on internet literature, the bagrada bug will lay eggs on the leaves, and in many cases, the soil underneath the plants. Eggs are barrel shaped, initially white and trnturn orange with age. A single female can lay as many as 100 eggs within 2 to 3 weeks. The incubation period is 5 to 8 days. The above image shows what we presume is a neonate, newly hatched nymph found crawling on the soil surface. Note its size relative to the knife blade. J.C. Palumbo, Univ. of Arizona Here is a bagrada bug nymph, likely a 3rd instar, crawling along the bed surface. It appears to have a round shape body typical of stink bug nymphs, with horizontal stripes across the top of its abdomen. Again, note its small size relative to the knife blade. Damage: Both adults and nymphs feed by sucking on the foliage of the crop. Starting on the edges of the leaves, white patches become visible, eventually the leaves wilt and dry. Young pl/dlilants/seedlings often die compllletely h//lhttp://www.larsen‐twins. dk/22bagra da. htm l Bagrada bugs damage plants by feeding on ygyoung leaves. Both adults and nypymphs suck sap from leaves, which may wilt and later dry. Considerable damage is caused to young plants, which may die or have the growth points severely damaged. Significant damage may also be caused to older plants. Bagrada bugs are major pests of cultivated crucifers. Severe infestations on cabbage result in stunted plants, leaves turning yellow with a rough texture, and death of the growing point. As a result, damaged plants do not produce heads or produce two or more small unmarketable heads instead of a large central head. http://www.infonet‐biovision.org/default/ct /103/pests Damage caused by the bagrada bug on cabbage © B. Loehr, icipe Symptoms The bugs, especially in the early stages of development, gather in masses and suck the sap from plants. Feeding by the bugs causes small puncture marks visible as white patches starting on the edges of leaves. Eventually the leaves wilt and dry. Heavily attacked plants may have a scorched appearance. http://www.infonet ‐biovision.org/default/ct/103/pests Feeding results in large stildippled or wilte d areas on leaves. Often the growth of newly formed central shoots or heads of plants become stunted. Populations can build up quickly reaching damaging densities that require control. Heaviest infestations are typically observed in organic farms, commu nity gardens, and residential veetableegetable gardens were little or no pesticides are used. http://cisr.ucr.edu/bagrada_bug.html Initial symptoms of damage by bagrada bugs . Note small white punctures on the edges of leaves. © A. M. Varela, icipe J.C. Palumbo, Univ. of Arizona Feeding punctures and white patches on the edges of leaves on a young leaf of a cauliflower transplant in an organic field ,Coachella Valley, CA, Sep 2009. Bug numbers were high throughout the field. J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona Damage on leaves might be mistaken for herbicide damage J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona Feeding damage that resulted in the dried young terminal leaf of a cauliflower transplant in an organic field , Coachella Valley, CA, Sep 2009. J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona Feeding damage and stunting of a broccoli seedling (~4 weeks after wet date) from bagrada bug feeding, Coachella Valley, CA, Sep 2009. J.C. Palumbo, Univ. of Arizona J.CfC. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona J.C. Palumbo, Univ. of Arizona Adult bragada bug feeding on broccoli cotyledon, Coachella Valley, CA, Sep 2009. Note: the mouthparts underneath head inserted into leaf tissue (arrow) Control: Based on literature from Nambia, the action threshold for treatment suggests that control measurements should start if 1 bug/m² is found infesting plants at early plant growing stages (the populations found in the organic cole crops in Coachella clearly exceeded this threshold). If the crop is past the early growing stage, a higher threshold level of three bugs/m² is suggested. http://www.infonet-biovision.org/default/ct/103/pests Anecdotal observations by PCAs in Coachella and Yuma suggest that pyrethroids applied as sprinkler chemigation or foliar spray treatments during stan d es ta blis hmen t have been e ffec tive in killing the a du lts an d preven ting damage. This included Asana and Warrior specifically. It is unknown at this time whether soil or foliar applications of neonicotinoids (Admire Pro, Alias, Assail,,,)p Venom, etc) will provide cost-effective control. We have a lot to learn about this new potential pest. It may not amount to much and may only be a short term issue. However, we strongly recommend that you contact us if you have any additional information to share with the industry..
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