BIOLOGY, IMPACT, AND MANAGEMENT OF SOYBEAN INSECT PESTS IN SOYBEAN PRODUCTION SYSTEMS.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0233026
• Multistate No.: S-1055
• Project Start Date: Feb 1, 2013
• Project End Date: Sep 30, 2017
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF KENTUCKY
500 S LIMESTONE 109 KINKEAD HALL
LEXINGTON,KY 40526-0001

Performing Department
Entomology

Non Technical Summary
Soybean production is increasing to meet the world demand for protein amid dwindling food supplies. Since 2009, the US has produced over 3 billion bushels of soybeans, generating $32 billion in production value (NASS). However, various native and invasive insect pests whose distributions are rapidly expanding and adapting to management practices threaten soybean yield and quality. In the Mid-South, up to 70% of acreage is treated for stink bugs, corn earworm, and other lepidopteran defoliators each year, with the estimated value of yield loss plus management costs of $51.76 per acre. In the Midwest, untreated economic soybean aphid infestations can further reduce production value by 3%, causing an estimated annual loss of $2.4 billion (Tilmon et al. 2011). In the short-term, loss of current highly effective management tactics due to expanding pest complexes is increasing producer costs. In the long-term, the establishment of invasive insect pests will continue to impact soybean ecosystems, including interactions with native pests and the biological control offered by various natural enemies. To address these concerns, coordinated research and Extension delivery are necessary to rapidly understand native and invasive pest biology, develop best management practices, and deliver recommendations to soybean producers.

Animal Health Component

80%

Research Effort Categories

Basic

20%

Applied

80%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
215	1820	1130	50%
216	1820	1130	50%

Knowledge Area
215 - Biological Control of Pests Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
1820 - Soybean;

Field Of Science
1130 - Entomology and acarology;

Keywords

soybean

pests

natural enemies

parasitoids

predators

biological control

Goals / Objectives
Develop coordinated applied best management practices

Project Methods
Survey for the presence, establishment and spread of emerging pests -Participants: Erin Hodgson (IA), Ames Herbert (VA), Jeff Davis (LA), Ron Hammond (OH), Andy Michel (OH), Christian Krupke (IN), Ken Yeargan (KY), Fred Musser (MS), Thomas Hunt (NE), Tiffany Heng-Moss (NE), Kelley Tilmon (SD), Brian McCornack (KS), Jeremy Greene (SC), Bruce Potter (MN), Dominic Reisig (NC), J. Knodel (ND) --Existing, multi-state sampling efforts and development of new, common protocols to monitor the spread of pests throughout the soybean-growing region will be explored. Understand soybean pest interactions -Participants: Jeff Davis (LA), Andy Michel (OH), John Reese (KS), Christian Krupke (IN), Ken Yeargan (KY), Louis Hesler (USDA-SD), Fred Musser (MS), Thomas Hunt (NE), Tiffany Heng-Moss (NE), Kelley Tilmon (SD), Brian McCornack (KS), Jeremy Greene (SC), Bruce Potter (MN), Dominic Reisig (NC). Soybean insect pests interact with not only soybean, but other pests, pathogens (including as vectors for plant disease), natural enemies, host plant quality, resistance and tolerance (i.e., varieties), and abiotic factors (e.g. nutrients, insecticides).

Progress 02/01/13 to 09/30/17

Outputs
Target Audience:Soybean producers in western Kentucky received information from this project. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Results have been presented at extension meetings in western Kentucky. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The influence of habitat surrounding soybean felds on pests and natural enemies was quantified.

Publications

• Type: Journal Articles Status: Published Year Published: 2017 Citation: Penn, HJ and AM Dale. 2017 Imidacloprid seed treatments affect individual ant behavior and community structure but not egg predation, pest abundance or soybean yield. Pest Management Science 73: 1625-1632.

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Other researchers and extension educators Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Crop field margins provide benefits to growers by provisioning alternative food resources and refuges for predators. Pests are known to interact with margins in different ways depending on host plant requirements and dispersal modes, altering their within field interactions with predators. This study quantified soybean pest and spider abundances in relation to margin composition and scale. Within field spatial distributions of soybean pests and spiders in relation to field margins, community abundances, and abiotic conditions were determined to elucidate potential pest-spider interactions. Pest and spider abundances in soybean fields were positively correlated with each other and with increased wind speed. Pest abundance increased if field margins were located from 0-10 m but not 10-20 m and were composed of soybeans. Spider abundances only benefitted from the presence of wooded margins 10-20 m from the field. Both pest and spider Spatial Analysis by Distance IndicEs were impacted by margin type and distance interactions. Pests were more likely to exhibit non-random spatial patterns when pest abundances were small, early in the season. When spider spatial associations to pests were analyzed, the likelihood of spider aggregation increased with the presence of pest aggregations. Wooded and grass margins from 10-20 m also increased the chances of positive spatial overlap between pests and spiders. Our results indicate that pest and spider abundance in soybeans was dictated by a combination of abundance, land use, and abiotic conditions. Woody areas proved to be a source for spider populations; and this effect was increased with greater wind speed, potentially allowing greater spider dispersal. Additionally, spiders were more likely to overlap with pest populations earlier in the season, indicating that early season predation might be occurring as spatial overlap has been shown to indicate predation in previous studies. To increase the likelihood of predation events via conservation biocontrol, growers should ensure that soybean fields are not immediately adjacent to each other.

Publications

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:Other scientists working on management of soybean pests. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?I am retiring on 1 January 2016.

Impacts
What was accomplished under these goals? Soybeans were sampled from late vegetative through reproductive plant growth stages at approximately weekly intervals for pest insects and predaceous insects and spiders. Pest species were below economically injurious levels, but the following were present: green cloverworms, Japanese beetles, bean leaf beetles, stink bugs, and low levels of the soybean aphid. Among the stink bugs, the green stink bug accounted for 95% of the total. Brown marmorated stink bugs were found at low levels. Nabis and Geocoris species were the dominant Hemipteran predators, with Geocoris more than four times as abundant as Nabis. Very few Orius were collected. Harmonia axyridis (57% of total lady beetles) and Coleomegilla maculata (35%) accounted for most of the lady beetles collected, with the remainder being Cycloneda munda. The striped lynx spider was the most abundant type of spider, accounting for 51% of these predators. Other types of spiders present were Thomisidae (15% of total spiders), Tetragnathidae (14%), Salticidae (12%), and miscellaneous spiders (8%).

Publications

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: Primarily other scientists working on the management of soybean pests. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Soybeans were sampled by sweep net from mid vegetative stages until full pod stage at weekly intervals for pests and beneficial predators. Green cloverworm caterpillar numbers were consistent throughout the season but remained relatively low. The most abundant pests were bean leaf beetles and green stink bugs, with the latter being unusually abundant. Green stink bugs accounted for more than 95% of the total stink bugs collected. No brown marmorated stink bugs were collected during sampling but a few of these exotic stink bugs were noted on nearby plants. Damsel bugs (Nabis spp.) and bigeyed bugs (Geocoris spp.) were among the most abundant insect predators found.Striped lynx spiders were the most abundant type of spider predators, accounting for 44.2% of all spiders collected. This differed markedly from the representation of lynx spiders in Kentucky soybean fields three decades earlier, when lynx spiders accounted for less than one per cent of the foliage inhabiting spiders. The next most abundant kinds of spiders were jumping spiders, orb weavers, and crab spiders, respectively. Although soybean aphids were not quantified, it was apparent that there were consistent, low to moderate populations present throughout most of the season. This likely accounted for the relatively high populations of lady beetles found on soybean this year. The majority of those lady beetles were Harmonia axyridis, which accounted for more than 80% of the total lady beetles collected. Most of the other lady beetles were Coleomegilla maculata, with other species accounting for less that 2% of the total lady beetles.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: Colvin, S.M., and K.V. Yeargan. 2014. Predator fauna associated with oleander aphids on four milkweed species and the effects of those host plants on the development and fecundity of Cycloneda munda and Harmonia axyridis. Journal of the Kansas Entomological Society. 87: 280-298.

Progress 02/01/13 to 09/30/13

Outputs
Target Audience: Other scientists working on the management of soybean pests. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Soybeans were sampled by sweep net during vegetative and reproductive plant growth stages for pests and natural enemies (predators). The most abundant pest species were bean leaf beetles, with lesser numbers of green cloverworms and stink bugs. Green stink bugs accounted for the majority (74%) of stink bug pests, with brown stink bugs making up most of the rest. The invasive brown marmorated stink bug was not collected. The most abundant predators included damsel bugs, minute pirate bugs, big-eyed bugs, lady beetles, and spiders. Lady beetles were more abundant than expected, given the low numbers of aphids, and consisted primarily of Harmonia axyridis and Coleomegilla maculata, with the former accounting for more than 80% of the lady beetles. All collected Harmonia were adults and the only lady beetle species collected in the larval stage was Coleomegilla maculata. Predominant spiders included orb weavers, crab spiders, jumping spiders, and lynx spiders. The striped lynx spider accounted for 24.6% of all spiders collected. When spiders in Kentucky soybeans were intensively sampled some three decades ago over a three-year period, striped lynx spiders accounted for less than one per cent of the total foliage inhabiting spiders. This species traditionally has been abundant in crops in the southernmost USA but it may be increasing in abundance at more northerly locations.

Publications

• Type: Journal Articles Status: Published Year Published: 2013 Citation: Colvin, S.M., and K.V. Yeargan. 2013. Effects of milkweed host species on interactions between Aphis nerii (Hemiptera: Aphididae) and its parasitoids. Journal of the Kansas Entomological Society, 86: 193-205.