Pest control and resistance management through release of insects carrying a male-selecting transgene

Development and evaluation of new insect pest management tools is critical for overcoming over-reliance upon, and growing resistance to, synthetic, biological and plant-expressed insecticides. For transgenic crops expressing insecticidal proteins from the bacterium Bacillus thuringiensis (‘Bt crops’) emergence of resistance is slowed by maintaining a proportion of the crop as non-Bt varieties, which produce pest insects unselected for resistance. While this strategy has been largely successful, multiple cases of Bt resistance have now been reported. One new approach to pest management is the use of genetically engineered insects to suppress populations of their own species. Models suggest that released insects carrying male-selecting (MS) transgenes would be effective agents of direct, species-specific pest management by preventing survival of female progeny, and simultaneously provide an alternative insecticide resistance management strategy by introgression of susceptibility alleles into target populations. We developed a MS strain of the diamondback moth, Plutella xylostella, a serious global pest of crucifers. MS-strain larvae are reared as normal with dietary tetracycline, but, when reared without tetracycline or on host plants, only males will survive to adulthood. We used this strain in glasshouse-cages to study the effect of MS male P. xylostella releases on target pest population size and spread of Bt resistance in these populations

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

Late Season Boll Weevil Infestations and Survival in a Cotton Bolls in Arizona

Studies were conducted in Phoenix AZ, to determine the development of boll weevil, Anthonomus grandis Boheman, infestations in late - season cotton bolls, the pattern of boll weevil emergence, and survival /mortality in the bolls. Boll weevils emerged from bolls buried in moist vermiculite over a period of 232 to 239 days, from 29 January to 2 August. Higher percentages of emergence and lowest mortality in bolls occurred in bolls collected in November as compared to bolls collected in December. Few boll weevils emerged from bolls held under dry conditions in an outdoor insectary for 174 days. However, an average of 16% of the weevils were found alive in the dry bolls in late May

Comparative Trap Catches in Four Boll Weevil Trap Types

The 1985 and 1986 Cotton Reports have the same publication and P-Series numbers.Four trap types were used to trap boll weevils at 1 m heights, with and without grandlure, and 2 trap types were compared at 0.5 m height, with and without grandlure. The results indicate trap height may be an important factor in boll weevil catches at certain times during the cotton season. Also trap color, design and other factors may influence trap catches since traps not baited with grandlure caught high numbers of boll weevils during certain times during the cotton growing season

Early-season Cotton Square Removal with Ethephon and Initiation of Pink Bollworm Infestations

Ethephon applied at rates of 0.50 or 0.75 lb AI/acre removed early-season squares and delayed initiation of pink bollworm, Pectinophora gossvpiella (Saunders) infestations and reduced the number of infested bolls on early-season fruiting branches, without affecting yield except for ethephon at 0.751b AI /acre at one location. Higher rates of application reduced yields. In most cases, ethephon treatments delayed flowering but plants compensated for removal of early- season squares and equalled or surpassed accumulated flowering of untreated control plants later in the season