Theses and Dissertations

Issuing Body

Mississippi State University


Catchot, Angus Jr.

Committee Member

Gore, Jeffrey

Committee Member

Sarver, Jason

Committee Member

Bond, Jason A.

Committee Member

Cook, Donald R.

Date of Degree


Document Type

Dissertation - Open Access



Degree Name

Doctor of Philosophy


College of Agriculture and Life Sciences


Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology


Peanut, Arachis hypogaea (L.), provides good rotational benefits for subsequent crops. During 2017, 2018, and 2019, research was conducted to determine the defoliating caterpillar complex in peanut in Mississippi, create a sweep net threshold for the complex, and determine yield losses associated with defoliation. The complex is comprised of yellow-striped armyworm, Spodoptera ornithogalli (Guenée); soybean looper, Chrysodeixis includens (Walker); corn earworm, Helicoverpa zea (Boddie); fall armyworm, S. frugiperda (Coquillet); southern armyworm, S. eridania (Stoll); beet armyworm, S. exigua (Hübner); green cloverworm, Hypena scabra (Fabricius); velvetbean caterpillar, Anticarsia gemmatalis (Hübner); and granulate cutworm, Feltia subterranea (F.). There was a significant relationship between the number of caterpillars on a drop cloth and the number per 25 sweeps. Defoliation during vegetative and early reproductive stage peanut caused a delay in canopy closure for all levels of defoliation although yield losses of 11.2% only occurred when defoliation reached 100%. During late season, peanut yield was reduced by 13% when defoliation reached 50%. With these data, a sweep net sampling and defoliation threshold can be derived. Managing caterpillar pests all season is necessary to reduce chances of yield loss due to defoliation.