Abstract
The occurrence of phytophagous stink bugs in soybeans can result in production losses, if this pest is not properly controlled. Our objective was to study the vertical distribution (intra-plant) of nymphs and adults of Euschistus heros (Fabricius, 1798) (Hemiptera: Pentatomidae) in the leaf canopy of soybean plants, during the day. For this, fourteen soybean plants located in one meter of row were evaluated in the field, every three hours between 5 am and 8 pm. The sampled plants were divided into three strata (upper, middle, and lower), where nymphs and adults observed were counted in each stratum and sampling period. The treatments consisted of the three strata of the soybean plants and the different sampling points performed at each time of the day represented the repetitions. An irregular distribution of E. heros nymphs and adults was observed in the three studied strata of soybean plants, during the day. At 11 am and 2 pm, when the ambient temperature and solar radiation were highest, both the E. heros adults and the nymphs positioned preferentially on the upper stratum of the soybean plants and later migrated to the middle and lower strata when the temperature and solar radiation decreased. This information about the distribution pattern of E. heros in the soybean leaf canopy, during the day, provides knowledge for more effective monitoring and control of this pest in soybean crop.
Highlights
Brazil is currently the second largest producer of soybean, Glycine max (L.) Merrill (Fabaceae: Phaseoleae), in the world and has achieved expanded production and productivity with each new crop
This information was related to the spatial variability of these bugs in soybeans, since through the damages it was possible to verify that the insects were mostly present in the middle and lower strata of the plants, which does not agree with the results for vertical distribution of this species obtained in this work, especially during the hottest times of the day, when stink bugs migrated to the top of the soy canopy
Waite (1980) studied the behavior of nymphs and adults of N. viridula in soybean crop and found greater concentration in the upper part of the plants in the period from 7 to 11 am, corroborating with the results observed in this work for adults of E. heros at 11 am (Figure 3)
Summary
Brazil is currently the second largest producer of soybean, Glycine max (L.) Merrill (Fabaceae: Phaseoleae), in the world and has achieved expanded production and productivity with each new crop. In the 2018/19 season, soybean production in the country was 115,030.1 million tons, with a cultivated area of 35,874.1 million hectares and average productivity of 3.206 kg/ha (CONAB, 2019). This expansion of soybean cultivation can increase the occurrence of phytosanitary problems, such as a higher incidence of pests, diseases, and weeds (Oliveira & Hoffmann-Campo, 2003). As the population of this pest increases, the damage caused to the soybean crop becomes more and more significant, and in some cases, may become irreversible and cause significant loss in the production of grains or seeds (Corrêa-Ferreira & Panizzi, 1999)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
