Integrated pest management of the Mexican rice borer in Louisiana and Texas sugarcane and rice

Interactions between sugarcane, Saccharum spp., and the invasive species Mexican rice borer, Eoreuma loftini (Dyar), were evaluated in field experiments and in the greenhouse with rice, Oryza sativa L., as an additional host. By determining adult emergence holes together with percent bored internodes, a novel method for evaluating sugarcane cultivar resistance was developed. In 2001, LCP 85-384 had the greatest moth production per hectare, significantly higher (P ≤ 0.05) than HoCP 85-845. High levels of sodium and magnesium salt stress in the soil were associated with higher E. loftini injury in all cultivars except HoCP 91-555 and CP 70-321. Irrigation reduced injury in both susceptible (LCP 85-384) and resistant (HoCP 85-845) cultivars by 2.5-fold. The combination of irrigation, plant resistance, and insecticide applications of tebufenozide decreased injury from 70% bored internodes to less than 10%. Several free amino acids essential for insect development increased in sugarcane leaves under drought stressed conditions, which exacerbated E. loftini infestations. Drought stressed sugarcane was 1.8-fold more attractive based on egg masses/plant than non stressed sugarcane. Based on egg masses/plant and eggs/egg mass, cultivar LCP 85-384 was more attractive than the resistant HoCP 85-845. Egg masses were 9.2-fold more abundant on sugarcane than on rice. Oviposition on sugarcane occurred exclusively on dry leaf material, and the number of dry leaves was positively correlated with egg masses per plant. Several free amino acids essential for insect development increased in sugarcane leaves under drought stressed conditions, and were highly correlated with egg masses per plant. Rice leaves, despite being less attractive for oviposition, had higher levels of free amino acids than sugarcane. Based on boundary movement monitoring with pheromone traps, the average rate of spread from 1980 (Weslaco, TX) to 2004 (Chambers County, TX) was 23.2 km/yr. From 2000 to 2004, annual mean centroids of moth trap counts moved 29.3 km, however 95% C.I. overlapped across years. Minimizing sugarcane stress will play a major role in managing this invasive pest when it becomes established in Louisiana

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Development, survival, and feeding behavior of Helicoverpa zea (Lepidoptera: Noctuidae) relative to Bt protein concentrations in corn ear tissues.

The corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), preferentially oviposits and feeds on ears of corn (Zea mays L.) and can be managed using transgenic hybrids that produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). Concentrations of Bt proteins can vary spatially and temporally in plant tissues, creating a heterogeneous environment that can increase the risk of resistance development. We planted small-plot trials of nine Bt and non-Bt corn hybrids in South Carolina in 2016 and 2017 and investigated the development, survival, feeding injury, and feeding behavior in corn ear tissues. ELISA was used to quantify the concentrations of Cry1F and Cry2Ab2 in young silk, old silk, maternal tip tissue, kernels, and husk. Cry1F and Cry2Ab2 significantly varied with silk age and both proteins were generally highest in the silk and tip tissue. Hybrids with pyramided proteins significantly reduced feeding injury to the silk, tip, and kernel ear tissues, which was less apparent with single Bt protein hybrids. The pyramided hybrid expressing Vip3A incurred no injury to either the ear tip or kernels, and only eight 1st instar larvae were collected in the silk of 520 sampled ears. Age of larvae significantly varied among ear tissues but not between hybrids. Depending on hybrid family, mean larval instar in the silk, tip, and kernels was 1st or 2nd, 3rd, and 5th, respectively. Instar-specific feeding penetrance into corn ears increased with age but did not differ between hybrids. We characterized the instar- and tissue-specific feeding behavior of H. zea larvae but did not detect differences in feeding behavior between Bt and non-Bt hybrids. Implications for resistance management strategies such as seed mixtures are discussed

Impact of Planting Date and Insecticide Application Methods on Melanaphis sorghi (Hemiptera: Aphididae) Infestation and Forage Type Sorghum Yield

Studies on the management of the invasive Melanaphis sorghi are essential to refining integrated pest management strategies against M. sorghi in forage sorghum in the USA. The objective of this study was to determine the impact of planting date (early planting and late planting) and in-furrow and foliar insecticide application of flupyradifurone, on M. sorghi infestation and forage sorghum yield in Tifton, Georgia and Florence, South Carolina, USA, in 2020 and 2021. Early planted sorghum supported slightly higher aphid density and severity of infestation as evident in the greater cumulative insect days values in the early planted sorghum at both Florence and Tifton in 2020 and 2021. A single foliar application reduced aphid infestations below the threshold level of 50 aphids per leaf. In contrast, in-furrow insecticidal application in selected plots at both locations significantly suppressed M. sorghi density to near-zero levels. Yield results in Florence in 2020 showed that sorghum yield was over 50% greater in early planted plots compared to late planted plots. Both insecticide treatments (foliar and in-furrow) resulted in significantly higher yield than untreated plots. These data indicate that early planting coupled with in-furrow and foliar insecticide applications can suppress M. sorghi infestations and improve silage production in forage sorghum in the USA