Existing crop monitoring programs determine the incidence and distribution of plant diseases and pathogens and assess the damage caused within a crop production region. These programs have traditionally used observed or predicted disease and pathogen data and environmental information to prescribe management practices that minimize crop loss. Monitoring programs are especially important for crops with broad geographic distribution or for diseases that can cause rapid and great economic losses. Successful monitoring programs have been developed for several plant diseases, including downy mildew of cucurbits, Fusarium head blight of wheat, potato late blight, and rusts of cereal crops. A recent example of a successful disease-monitoring program for an economically important crop is the soybean rust (SBR) monitoring effort within North America. SBR, caused by the fungus Phakopsora pachyrhizi, was first identified in the continental United States in November 2004. SBR causes moderate to severe yield losses globally. The fungus produces foliar lesions on soybean (Glycine max) and other legume hosts. P. pachyrhizi diverts nutrients from the host to its own growth and reproduction. The lesions also reduce photosynthetic area. Uredinia rupture the host epidermis and diminish stomatal regulation of transpiration to cause tissue desiccation and premature defoliation. Severe soybean yield losses can occur if plants defoliate during the mid-reproductive growth stages. The rapid response to the threat of SBR in North America resulted in an unprecedented amount of information dissemination and the development of a real-time, publicly available monitoring and prediction system known as the Soybean Rust-Pest Information Platform for Extension and Education (SBR-PIPE). The objectives of this article are (i) to highlight the successful response effort to SBR in North America, and (ii) to introduce researchers to the quantity and type of data generated by SBR-PIPE. Data from this system may now be used to answer questions about the biology, ecology, and epidemiology of an important pathogen and disease of soybean.

Tobacco thrips (Frankliniella fusca) and tomato spotted wilt (TSW) orthotospovirus (family Tospoviridae, genus Orthotospovirus) can reduce peanut (Arachis hypogaea L.) yield. Systemic insecticides are applied in the seed furrow at planting and to peanut foliage to reduce injury from tobacco thrips and decrease incidence of TSW. Research was conducted in Georgia, North Carolina, South Carolina, and Virginia in 2013 and 2014 to compare the effect of the following treatments on tobacco thrips feeding injury and expression of TSW in peanut: thiamethoxam seed treatment, thiamethoxam seed treatment followed by acephate 3 weeks after planting, phorate applied in the seed furrow at planting, and a nontreated check. Tobacco thrips feeding injury and TSW incidence were significantly higher in thiamethoxam and thiamethoxam followed by acephate-treated peanut than peanut treated with phorate. Thiamethoxan seed treatment followed by acephate resulted in significantly lower tobacco thrips feeding injury compared to thiamethoxam seed treatment alone. Yield of Virginia market type cultivars was greater when thiamethoxam was followed by acephate applied to peanut foliage or when phorate was applied compared with nontreated peanut or the seed treatment alone. Runner market type cultivars yielded higher when phorate was applied compared with nontreated peanut while peanut treated with thiamethoxam with or with acephate yielded similar to both of these treatments.

Core Ideas Bradyrhizobia inoculant increases peanut yield in new peanut fields and in fields with a recent history of peanut. Applied nitrogen is less effective than inoculation with Bradyrhizobia in new peanut fields. Return on investment from Bradyrhizobia inoculant occurs regardless of field history relative to peanut production. Adequate nitrogen (N) fixation by peanut (Arachis hypogaea L.) is essential to optimize yield. In replicated trials in North Carolina, South Carolina, and Virginia from 1998–2017, commercially available in‐furrow liquid or granular inoculant increased yield from 3460 to 4660 lb/acre in new peanut fields (52 trials) and 4280 to 4450 lb/acre in fields with a previous history of peanut plantings within the past 4 years (43 trials). The increase in economic value from inoculation treatment ($8/acre) at a peanut price of $535/ton was $318/acre and $41/acre in fields with these respective histories. In a second experiment, replicated trials were conducted from 2007–2017 in fields without a history of peanut production or fields not rotated to peanut within at least the past 20 years. Economic return based on peanut prices described previously was determined to reflect cost of N applied as ammonium sulfate ($0.28/lb ammonium sulfate) as a single application 45 to 60 days after planting when canopy foliage began to express N deficiency. A linear or quadratic response to rates of 0, 60, 90, 120, and 150 lb N/acre was noted in five trials with no response observed in the remaining four trials. When these experiments were included with five other experiments where non‐inoculated and inoculated controls were compared with one rate only (120 lb N/acre), yield and economic return were greater for inoculated peanut compared with peanut receiving N or the non‐inoculated and non‐fertilized control. Nitrogen increased peanut yield and economic return compared with the non‐fertilized control. Results from these experiments underscore the value of inoculation with Bradyrhizobia at planting regardless of field history and the limitations of applied N to correct N deficiencies in peanut.

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