Researchers at Purdue University and the University of Illinois have find a corn variation whose leaf are highly susceptible to attack by westerly corn rootworm beetles , a pest that feed in the first place on corn silk and pollen .
While western clavus rootworm beetles were previously thought to forfend corn leaves based on food - source preference , study of the mutant suggests that normal corn plants have an fighting defense chemical mechanism that deters the beetles from fertilise on their leaf . Identifying this mechanics could lead to fresh strategies for control westerly corn rootworm , which is the most destructive insect pest of edible corn in the U.S.
“ This unfold up a whole new chance to understand more about the mechanism of defense in corn to assure this beetle , ” enounce Gurmukh Johal , professor of botany and plant pathology at Purdue . Johal and Stephen Moose of Illinois severally hear the mutant around the same fourth dimension .
“ In identify the genetic pathway involved in resistance , we can grow better ways of controlling this plague without having to practice insecticides , ” Johal suppose .
Western corn rootworm causes more than $ 1 billion impairment a twelvemonth in yield losses and dominance monetary value in the U.S. , garner it the nickname “ the billion - dollar hemipteran . ” The rootworm larvae manduction on the roots of corn works while the adult beetle eat the silks and pollen . Current control measures include harvest rotation , transgenic corn plants and insect powder , but a rise in continuous corn systems , increase rootworm opposition to transgenic plants and changes in rootworm behavior have rendered these management strategies less good .
Because the leaves of the corn mutant are singularly attractive to westerly corn whiskey rootworm beetles , the mutant could be used in a “ push - pull ” plague - direction scheme , tempt the mallet to a specific location where they can be see to it , tell Christian Krupke , helper prof of bugology at Purdue and co - author of the study .
“ Once you may get them where you want , you may use efficient , cost - good ways of controlling them , either by directly targeting and annihilate them or by keeping them away from your main crop , ” Kurpke says .
In the absence of the beetle , the mutant is well-nigh identical from normal corn plants , which could be why it was not fall upon earlier , Johal allege . Its leave do not become vulnerable to attack by rootworm beetles until it reaches the vegetational stage , about five to six weeks into the growth operation .
On feel the mutant , western corn rootworm beetle scrape forth the folio tissue paper from the upper epidermis , resulting in a limpid “ window pane ” show . If the mallet infestation is severe , the plants can become completely defoliate , which also can reduce grain take .
A combination of structural and biochemical changes in the mutant leave make them particularly vulnerable to attack . The cellular lobes that interlock to provide structural strength are smaller and weaker in the mutant leaves . The leaves also have substantially reduced levels of hydroxycinnmates and lignin , compounds that are responsible for thwartwise - linking microfibers in prison cell walls .
Further enquiry is being done on the possibility of using the variation in pest - control strategies and key out the genetic nerve tract in normal corn plant that prevents western Zea mays rootworm beetles from deplete their parting . The genes could be used to make clavus plants more pest - repellent , Johal say .
The paper was issue online inPLoS ONE .
