Population dynamics of exotic rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on coconut as influenced by weather factors and natural enemies

The rugose spiralling whitefly, Aleurodicus rugioperculatus Martin is a new exotic pest occurring in several crops including coconut since 2016 in India. Due to variation in the agro-climatic conditions of different regions, arthropods show varying trends in their incidence also in nature and extent of damage to the crop. Besides, abiotic factors also play a key role in determining the incidence and dominance of a particular pest and their natural enemies in a crop ecosystem. The population dynamics of new exotic whitefly species, A. rugioperculatus and their associated natural enemies was assessed on five-year-old Chowghat Orange Dwarf coconut trees at Coconut Farm of Tamil Nadu Agricultural University. The study indicated that RSW was found throughout the year on coconut and the observation recorded on weekly interval basis shows that A. rugioperculatus population escalated from the first week of July 2018 (130.8 nymphs/leaf/frond) reaching the maximum during the first week of October (161.0 nymphs/leaf/frond) which subsequently dwindled to a minimum during April. The parasitisation by E. guadeloupae on RSW ranged from 31.60 percent in Aug. 2018 to 57.60 percent in December 2018. The association of biotic and abiotic factors with A. rugioperculatus population showed a negative correlation with E. guadeloupae and C. montrouzieri. There was a significant positive correlation between maximum temperature and minimum temperature as well as relative humidity. However, rainfall showed a negative correlation with A. rugioperculatus population

Studies on the predator Apertochrysa astur (Banks) (debris carrying green lacewing) on invasive coconut whiteflies

The invasive whitefly species, rugose spiralling whitefly (RSW) and Bondar’s nesting whitefly (BNW) (Hemiptera: Aleyrodidae) were reported on coconut in 2016 at Pollachi, Tamil Nadu, India and in 2019 in Kerala, India, respectively. Among the natural enemies of whiteflies, Apertochrysa astur (Banks) is the predominant predator observed in the coconut ecosystem. The population effect of RSW and BNW in different host plants, viz., coconut, banana and custard apple, on the growth and development of the A. astur were studied. Further, the effects of A. astur and yellow sticky traps (YSTs) were evaluated against the invasive whiteflies of coconut. The growth and development of the grubs of A. astur were better when fed with the RSW and BNW reared in coconut, followed by custard apple and banana. The weight of the 1st, 2nd and 3rd instar grubs were 0.25 mg, 0.62 mg and 2.46 mg, respectively. The pre-pupal weight was 7.41 mg, and that of the pupa and adult were 8.35 mg and 12.27 mg when fed with RSW. Similarly, when A. astur was fed with BNW reared on coconut, the weight of the 1st, 2nd and 3rd instar grub of A. astur was 0.22 mg, 0.59 mg and 2.24 mg, respectively. The pre-pupal weight was 7.06 mg, and that of the pupa and adult were 8.22 mg and 12.01 mg, respectively. Among the different treatment dosages of A. astur eggs and YSTs evaluated, 3 YST and 10 A. astur eggs palm-1 were highly effective as they reduced RSW and BNW population by 59.7 per cent and 56.7 per cent per cent, respectively. The grubs of A. astur were observed to be extremely efficient in reducing the population of A. rugioperculatus and P. bondari. The results supported that A. astur can be employed as an efficient biological control agent for managing invasive whitefly species in the coconut ecosystem

Biology and predatory potential of chrysopids on invasive coconut rugose spiralling whitefly Aleurodicus rugioperculatus Martin

The relatively new invasive rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus (Hemiptera: Aleyrodidae) has become a serious threat to oil palm, particularly coconut plantation, in southern India. Here, we report biology and foraging potential of predatory neuropteran Green lace wings Chrysoperla zastrowi sillemi (Esben-Petersen) and Mallada boninensis (Okamoto) (Chrysopidae) on against RSW. Results revealed that A. rugioperculatus served as a suitable host for the both chrysopid predators. C. z. sillemi completed its life cycle in 19.91±1.90 days with a larval (grub) period of 9.44±3.91 days and adult longevity was 24.10±1.87 days. The developmental period of M. boninensis was 22.3±2.93 days, with a larval period of 11.85±1.71 days, while the adult longevity was 19.25±1.52 day. In the laboratory experiment, all the larval stages of the predators were observed to feed on A. rugioperculatus. It was observed that the 3rd instar grub of C. zastrowi sillemi with the developmental period of 3.24±1.73 days consumed a maximum of 313.2 whiteflies (all the life stages) followed by second and 1st instar grub stages of the predator, which consumed mean number of 200.2 and 140.2 eggs and nymphs of A. rugioperculatus, respectively during their developmental period of 3.58±1.84 and 2.62±1.34 days, respectively. In the case of M. boninensis, a single grub could consume a total of 929.8 whiteflies (both eggs and nymphal stages) during its total larval period of 9.44±3.91 days

Insecticidal activity and changes in midgut histology of the generalist herbivore, Spodoptera litura F. (Lepidoptera: Noctuidae) in response to seed extract of Annona squamosa Linn.

The tobacco caterpillar, Spodoptera litura F., is one of the most devastating, cosmopolitan polyphagous pests affecting major crops that significantly impact agricultural productivity. The present study aimed to evaluate the toxicological effect of seed extract of the medicinal plant, Annona squamosa L. and the histological effect on the midgut of Spodoptera litura F., under laboratory conditions. The crude methanolic extract of A. squamosa seed was tested against the third instar larvae of S. litura at five different concentrations viz., 0.5%, 1.0%, 1.5%, 2.0% and 2.5 % by leaf dip bioassay method. The seed extract exhibited larval mortality of 96.67%, 83.37 %,70%, 53.33% and 40 % at the concentrations 2.5 %, 2.0%, 1.5%, 1.0% and 0.5%, respectively.The results indicated that the response of larval mortality to the seed extract was dose-dependent. The dose of 0.5% showed the lowest mortality (40.00%), while the dose of 2.5 % showed maximum larval mortality (96.67%). Hence they were subjected to histological analysis. The anatomical sectioning of S. litura larval midgut treated with 0.5% concentration showed disruption in the peritrophic membrane and striated border of epithelial cells. The midgut of larvae treated with 2.5 % concentration showed an irregular epithelium and high vacuolization in the cytoplasmic cells. The results indicated that methanol extract of A. squamosa seed extract has the ability to cause changes in the midgut region, thereby affecting the digestion and nutrient absorption of S. litura larvae, which will lead to a debilitating effect on the development of larvae. Based on the present study A. squamosa seed extract will be a potential biopesticide for managing S. litura

Biology and predatory potential of chrysopids on invasive coconut rugose spiralling whitefly Aleurodicus rugioperculatus Martin

814-818The relatively new invasive rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus (Hemiptera: Aleyrodidae) has become a serious threat to oil palm, particularly coconut plantation, in southern India. Here, we report biology and foraging potential of predatory neuropteran Green lace wings Chrysoperla zastrowi sillemi (Esben-Petersen) and Mallada boninensis (Okamoto) (Chrysopidae) on against RSW. Results revealed that A. rugioperculatus served as a suitable host for the both chrysopid predators. C. z. sillemi completed its life cycle in 19.91±1.90 days with a larval (grub) period of 9.44±3.91 days and adult longevity was 24.10±1.87 days. The developmental period of M. boninensis was 22.3±2.93 days, with a larval period of 11.85±1.71 days, while the adult longevity was 19.25±1.52 day. In the laboratory experiment, all the larval stages of the predators were observed to feed on A. rugioperculatus. It was observed that the 3rd instar grub of C. zastrowi sillemi with the developmental period of 3.24±1.73 days consumed a maximum of 313.2 whiteflies (all the life stages) followed by second and 1st instar grub stages of the predator, which consumed mean number of 200.2 and 140.2 eggs and nymphs of A. rugioperculatus, respectively during their developmental period of 3.58±1.84 and 2.62±1.34 days, respectively. In the case of M. boninensis, a single grub could consume a total of 929.8 whiteflies (both eggs and nymphal stages) during its total larval period of 9.44±3.91 days

Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic