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PARASITISM, BIOLOGICAL control of insects, SQUASHES, HEMIPTERA, HYMENOPTERA, COVER crops, and BROOD parasitism

In a survey of egg parasitism by I H. pennsylvanicus i on I A. tristis i egg mases collected from 30 counties in Virginia, parasitism ranged from 0-100% of egg masses with 39.4% of egg masses parasitized in 2014 and 49.4% parasitized in 2015 [[5]]. In a two- year field study in Maryland, I H. pennsylvanicus i accounted for over 99% of egg parasitism and the average parasitism rate was 55.7% for wild eggs and 21.8% for sentinel eggs [[3]]. Results From 2016-2021, 2226 wild squash bug egg masses were collected, 2180 (98.0%) I A. tristis i egg masses and 46 (2.0%) I A. armigera i egg masses. 26759367 4 Cornelius M.L., Vinyard B.T., Gates M.W. Use of flowering plants to enhance parasitism and predation rates on two squash bug species Anasa tristis and Anasa armigera (Hemiptera: Coreidae). [Extracted from the article]

Viability of cells of Listeria monocytogenes or Salmonella spp. was quantified on slices of a German‐style bologna manufactured by a local butcher to contain no added antimicrobials or to include 0.9% or 1.3% of a blend of potassium acetate and sodium diacetate (K‐Ace) or 2.5% of a blend of potassium lactate and sodium diacetate (K‐Lac) as ingredients. After slicing (ca. 7.1 cm L by 6.7 cm W, ca. 0.5 cm thick, ca. 22.4 g each), a single slice of bologna was placed into a nylon–polyethylene bag and surface inoculated with 250 μL per side of a five‐strain mixture of either cells of L. monocytogenes or Salmonella spp. to achieve an initial level of ca. 3.5–4.0 log CFU/ slice. The packages were vacuum‐sealed and then stored at 4 or 12°C for 90 and 30 days, respectively. Without antimicrobials added to the formulation, L. monocytogenes numbers increased by ca. 5.4 and 6.0 log CFU/slice at both 4 and 12°C during the entire 90‐ and 30‐day storage period, respectively. Likewise, levels of Salmonella also increased by ca. 6.0 log CFU/slice at 12°C in the absence of added antimicrobials; however, levels of this pathogen decreased by ca. 1.7 log CFU/slice after 90 days at 4°C. With the inclusion of 0.9% or 1.3% K‐Ace or 2.5% K‐Lac in the bologna formulation, levels of L. monocytogenes decreased by ca. ≤0.7 log CFU/slice after 90 days at 4°C, whereas levels of Salmonella decreased by ca. 1.6–2.3 log CFU/slice. After 30 days at 12°C, levels of L. monocytogenes increased by ca. ≤3.4 log CFU/slice on product containing 0.9% K‐Ace or 2.5% K‐Lac but remained relatively unchanged on slices formulated with 1.3% K‐Ace. For Salmonella, in the presence of 0.9% or 1.3% K‐Ace or 2.5% K‐Lac, pathogen levels decreased by ca. ≤0.7 log CFU/slice at 12°C after 30 days. Our data validate that the inclusion of K‐Ace (0.9% or 1.3%) or K‐Lac (2.5%) as ingredients is effective for controlling L. monocytogenes and Salmonella on slices of bologna during refrigerated storage. [ABSTRACT FROM AUTHOR]