Infection Mechanisms and Colonization Patterns of Fungi Associated with Soybean

Fungi have many kinds of unique associations with plants. These associations can benefit both the fungus and the plant, or can be detrimental to the plants and cause disease and even plant death. Land plants evolved over 425 million years ago, and fungi have been associated with their evolutionary development over the millennia. In reference to nutrient sequestration, fungal associations with plants are characterized as biotrophic, necrotrophic, or a mixture of these types. Biotrophs usually grow only on living plant tissue extracting nutrients from living plant cells. They can be pathogenic or symbiotic. In a symbiotic relationship, fungi gain carbon from the plant in exchange for nutrients and water unattainable by the plant. Necrotrophs promote host cell death to acquire nutrients for growth and reproduction. Each type of association is equipped with its own unique collection of biochemical and mechanical infection and colonization mechanisms. In turn, plants have evolved to have a complex network of genes to interact with a broad range of fungi. This chapter will provide an overview of three different types of fungal infection and colonization patterns with examples relevant to soybean as well as define defense mechanisms that the plant uses to interact with these microbes

Survivorship of soybean aphid biotypes (Hemiptera: Aphididae) on winter hosts, common and glossy buckthorn

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is a major pest of soybean, Glycine max (L.) Merr., both in Asia where it is native, and in the USA where it is adventive. The rapid spread and establishment of the soybean aphid in the USA since its discovery in 2000 was successful because of extensive soybean production in the Midwest and the wide distribution of common buckthorn, Rhamnus cathartica (L.), its preferred primary winter host. The survivorship of four soybean aphid biotypes on com­mon and glossy buckthorn, Frangula alnus Mill., were compared. Our study showed that nymph oviparae of soybean aphid biotypes 1, 2, 3 and 4 reached adulthood and produced eggs on glossy buckthorn. When com­paring morphs between the hosts, greater numbers were recorded on common than glossy buckthorn, with one exception where the number of eggs per bud for soybean aphid biotype 2 was not different between the hosts. We found for the first-time soybean aphid biotypes 2 and 3 apterous males produced on common and glossy buckthorn. Morphological descriptions of live and mounted alate and apterous males are presented

New records of invasive aphids (Hemiptera: Aphididae) on garlic mustard in the USA

Lipaphis alliariae Müller (Hemiptera: Aphididae) was identified from specimens collected in Lake County, Ohio, on the invasive garlic mustard, Alliaria petiolata (Bieb.) Cavara & Grande (Brassicaceae). The identification was performed on apterous viviparae using morphological and molecular data. Body color and shape of the cauda discriminated L. alliariae and L. pseudobrassicae Davis. Measurements of morphological characters of both species were similar, but they have distinct characters distinguishing them from L. erysimi Kaltenbach. Neighbor-joining analysis of cytochrome oxidase 1 (Cox1) barcoding indicated a close relation­ship of the aphids that feed on Brassicaceae, and the range of pair-wise distances for Cox1 barcoding of these species was 0.3–0.9%. Garlic mustard, Alliaria petiolata (Bieb.) Cavara & Grande (Brassicaceae) is a highly invasive weed species in the United States. It was brought from Europe in the 1800s for herbal uses and erosion control (Munger 2001; USDA 2022). Records of aphids that feed on garlic mustard include Aphis gossypii Glover, Brevicoryne brassicae Linnaeus, Lipaphis alliariae Müller, L. erysimi Kaltenbach, Myzus ascalonicus Doncaster, M. ornatus Laing, M. persicae (Sulzer), and Rhopalosiphoninus latysiphon Davidson (Blackman and Eastop 2022). Out of this list L. alliariae and L. erysimi were not included in the list of aphid species adventive to North America north of Mexico (Foottit et al. 2006; Skvarla et al. 2017). Our article presents new records of aphids on garlic mustard in the USA

New records of invasive aphids (Hemiptera: Aphididae) on garlic mustard in the USA

Lipaphis alliariae Müller (Hemiptera: Aphididae) was identified from specimens collected in Lake County, Ohio, on the invasive garlic mustard, Alliaria petiolata (Bieb.) Cavara & Grande (Brassicaceae). The identification was performed on apterous viviparae using morphological and molecular data. Body color and shape of the cauda discriminated L. alliariae and L. pseudobrassicae Davis. Measurements of morphological characters of both species were similar, but they have distinct characters distinguishing them from L. erysimi Kaltenbach. Neighbor-joining analysis of cytochrome oxidase 1 (Cox1) barcoding indicated a close relation­ship of the aphids that feed on Brassicaceae, and the range of pair-wise distances for Cox1 barcoding of these species was 0.3–0.9%. Garlic mustard, Alliaria petiolata (Bieb.) Cavara & Grande (Brassicaceae) is a highly invasive weed species in the United States. It was brought from Europe in the 1800s for herbal uses and erosion control (Munger 2001; USDA 2022). Records of aphids that feed on garlic mustard include Aphis gossypii Glover, Brevicoryne brassicae Linnaeus, Lipaphis alliariae Müller, L. erysimi Kaltenbach, Myzus ascalonicus Doncaster, M. ornatus Laing, M. persicae (Sulzer), and Rhopalosiphoninus latysiphon Davidson (Blackman and Eastop 2022). Out of this list L. alliariae and L. erysimi were not included in the list of aphid species adventive to North America north of Mexico (Foottit et al. 2006; Skvarla et al. 2017). Our article presents new records of aphids on garlic mustard in the USA

Management Strategies for the Control of Soybean Rust

The identification of Asian soybean rust in Paraguay in 2001(Morel and Yorinori, 2002) and its spread to over 90% of the soybean production in Brazil through the 2003 season has heightened the awareness that this disease will soon be a threat to production on the continental USA. With the yield losses this disease can cause it will have a big impact on the profitability of soybean production

New Records of aphids (Hemiptera: Aphididae) on Industrial Hemp in the US Midwest

Industrial hemp (Cannabis sativa L.) production in the USA is increasing, and with it the list of insects colonizing the crop. In this article, we report new records of Aphis craccivora Koch 1854, Aphis fabae Scopoli, Aphis gossypiiGlover 1763, Aphis spiraecola Patch 1914 and Myzus persicae (Sulzer 1776) on industrial hemp in East Lansing, Michigan in fall 2020. In addition, between 2017 and 2020, the number of suction trap sites detecting P. cannabisincreased, and as well as the number of sites with multiple weeks of detections. The timing of detection changed, from only late season (fall migrants) in 2017, to catches spanning spring, summer, and fall in 2019 and 2020. These changes likely reflect the increase in industrial hemp production in the landscape in the Midwestern US

Revision of the taxonomic status of \u3ci\u3eAphis floridanae\u3c/i\u3e Tissot (Hemiptera: Aphididae) using morphological and molecular insight

Morphological and cytochrome oxidase 1 (Cox1) data show that Aphis floridanae Tissot (Hemiptera: Aphididae) is not synonymous with A. nasturtii Kaltenbach. Instead, A. floridanae matches the morphological characters of A. impatientis Thomas. Additionally, the range of cytochrome oxidase 1 (Cox1) pair-wise distance of the multiple collections of A. impatientis on Cornus spp., Impatiens spp. and Erechtites hieraciifolius (L.) Raf. ex DC. is 0–0.39%. Therefore, we conclude that A. floridanae Tissot, 1933 is a junior synonym of A. impatientis Thomas, 1878, new synonymy. In addition, A. impatientis is re-described, including first descriptions of the ovipara and alate male of that species

Simulations of snow distribution and hydrology in a mountain basin

We applied a version of the Regional Hydro‐Ecologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and wind‐driven sublimation to Loch Vale Watershed (LVWS), an alpine‐subalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow distribution to photogrammetrically rectified aerial (remotely sensed) images. Snow redistribution was governed by a topographic similarity index. We subdivided each hillslope into elevation bands that had homogeneous climate extrapolated from observed climate. We created a distributed wind speed field that was used in conjunction with daily measured wind speeds to estimate sublimation. Modeling snow redistribution was critical to estimating the timing and magnitude of discharge. Incorporating elevation partitioning improved estimated timing of discharge but did not improve patterns of snow cover since wind was the dominant controller of areal snow patterns. Simulating wind‐driven sublimation was necessary to predict moisture losses