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Background: The pink bollworm, Pectinophora gossypiella (Saunders), is a devastating global pest of cotton that has caused substantial economic damage to Bt Bollgard-II® cotton plants in recent years due to the evolution of Bt resistance. The associated fitness cost is assumed to be one of the factors delaying the development of resistance against Bt transgenic crops. Hence, the present study was undertaken to assess the biological performance of pink bollworms by comparing the life history and demographic parameters of a resistant (Field-R) and susceptible (Lab-S) population. Results: Prolonged larval duration (23.40 days in Field-R vs 18.80 days in Lab-S population), total life cycle (male = 50.00 vs 42.80 days; female = 53.60 vs 46.20 days), reduced fecundity (100.60 vs 154.20 eggs/female) and fertility (88.00 vs 138.00 fertile eggs/female) was observed. The demographic parameters indicated a significant reduction in the net reproductive rate (184.27 vs 276.72), innate capacity for increase in number (0.11 vs 0.15), finite rate of increase in number (1.12 vs 1.16 female progenies produced/female/day), weekly multiplication rate (2.16 vs 2.86), potential fecundity (545.06 vs 634.11 eggs), number of hypothetical F2 females (33 955.65 vs 76 572.41), but longer mean length of generation (47.54 vs 37.74 days) and population doubling time (6.30 vs 4.62 days) in Field-R compared with Lab-S population. A stage-specific life table demonstrated the differences in survival rates between susceptible and resistant populations at various life stages, with the resistant population having higher generation mortality (0.22 vs 0.19). Conclusions: The study confirms the involvement of fitness costs associated with Bt resistance in P. gossypiella. Despite reduced reproductive fitness, the resistant population tried prolonging the larval stage as a compensatory mechanism to repair the damaged host tissues due to Bt intoxication and for accumulation of enough nutrient reserves for normal pupation and adult emergence. Presence of a high proportion of double Bt-resistant larvae in the field coupled with continued noncompliance with refug planting certainly favours the flaring up of this monophagous pest despite the observed fitness costs. The resistance cannot be effectively reversed unless suitable alternative management strategies are deployed. [ABSTRACT FROM AUTHOR]

Pectinophora gossypiella one of the most destructive pests of Bt cotton. P. gossypiella gradually became a serious threat after gaining resistance to Bt toxin after 2 decade owing to which resulted in huge economic losses to the cotton growers. Present investigation was carried in order to study the most favourable temperature of P. gossypiella for its growth and development under various altering temperature regimes (20:30°C, 24:30°C,28:30°C, 20:35°C, 24:35°C, 28:35°C, 20:40°C, 24:40°C and 28:40°C) of Integrated Pest Management Laboratory, Department of Entomology, PAU, Ludhiana during cotton crop season 2022-23. Three models (linear and nonlinear) were used to estimate the relation between temperature and development rate of different instars and stages of P. gossypiella. The results revealed that duration of all larval instars and total larval duration were significantly short at an alternating temperature of 28:40°C. The pupal duration, adult longevity and total developmental period of male and female were recorded significantly low at the alternate temperature of 28:40°C. The fecundity and survivability (egg, larval and pupal)was significantly highest at 28:30°C, whereas the larval and pupal weights were significantly highest at an alternate temperature of 28:35°C. The correlation between developmental parameters and fecundity showed significant negative correlation. The survival of egg, larva and pupa showed non-significant negative correlation, whereas the larval and pupal weights show non-significant positive correlation with alternate temperatures. Stinner nonlinear and Inverse second order polynomial model provided more suitable temperature conditions for the development of P. gossypiella. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium sp.) is the one of the major commercial fibre crops cultivated across the country. The yield is severely affected by insect pests and diseases. Pink bollworm, Pectinophora gossypiella (Saunders, 1844) is one of the major insect pests threatening the cultivation of cotton. The major constraint limiting cotton production is resistance, which prevails to date due to the indiscriminate use of the insecticides and noncompliance of the refugia. Hence the status of the pest needs to be ascertained periodically to initiate timely and dynamic management tactics. For conducting laboratory screening, a higher number of individuals is the prime requirement, which is facilitated through mass-rearing techniques. We have evaluated different oviposition substrates like paper and muslin cloth for enhancing the recovery of eggs. Our results are quite promising and the use of black muslin cloth has shown a recovery of eggs on par with natural substrate (cotton twig). Adoption of the artificial substrate has huge potential in rearing techniques and avoids drawbacks like tissue drying, carry-over of diseases and reusability. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the increasing incidence of pest resistance to transgenic crops producing Bacillus thuringiensis (Bt) proteins in the field, elucidating the molecular basis of resistance is important for monitoring, delaying and countering pest resistance. Previous work revealed that mutation or down‐regulated expression of the cadherin gene (PgCad1) is associated with pink bollworm (Pectinophora gossypiella) resistance to Cry1Ac, and 20 mutant PgCad1 alleles (r1‐r20) were characterized. Here, we tested the hypothesis that the ABC transporter PgABCC2 is a functional receptor for the Bt toxin Cry1Ac and that a mutation is associated with resistance. RESULTS: We identified and characterized the first resistance allele (rC2) of PgABCC2 in the laboratory‐selected Cry1Ac‐resistant strain AQ‐C2 of pink bollworm. The rC2 allele had a one‐base deletion in exon20, resulting in a frameshift and the introduction of a premature stop codon. This resulting PgABCC2 protein had a truncated C‐terminus, including the loss of the NBD2 domain. AQ‐C2 exhibited 20.2‐fold greater resistance to Cry1Ac than the susceptible strain, and its inheritance of Cry1Ac resistance was recessive and genetically linked to PgABCC2. When produced in cultured insect cells, recombinant wild‐type and rC2 mutant PgABCC2 proteins localized within the cell plasma membrane, although substantial cytoplasmic retention was also observed for the mutant protein, while the mutant PgABCC2 caused a 13.9‐fold decrease in Cry1Ac toxicity versus the wild‐type PgABCC2. CONCLUSIONS: PgABCC2 is a functional receptor of Cry1Ac and the loss of its carboxyl terminus (including its NBD2 domain) confers low‐level resistance to Cry1Ac in both larvae and in cultured cells. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The impact of trap type and height on the captures of adults of the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), was assessed in cotton fields in three experimental sites (Nikaia, Nees Karyes, and Koilada) in Central Greece. Initially, the effectiveness of three different traps (white Delta, red Delta, and green Funnel) was compared. Subsequently, white Delta traps were positioned at three heights, i.e., 30, 60, and 90 cm, above ground level. Overall, captures notably increased in all traps from late July to mid-September. Funnel traps had poor performance for the captures of P. gossypiella adults, as compared with the respective figures for the other two Delta traps. Specifically, in two experimental sites (Nikaia and Koilada), both Delta traps cumulatively captured significantly more adults than the Funnel trap throughout the monitoring period. In the third site (Nees Karyes), the red Delta trap captured in total significantly more adults than the other two tested traps. Moreover, we found that traps in Nikaia placed at 90 cm captured significantly less adults as compared with the other two trap heights. The same trend was observed in Koilada; however, differences were significant only between traps at 30 and 90 cm. No significant differences were determined among different heights in the third site (Nees Karyes). These findings offer valuable insights for the monitoring protocols of P. gossypiella in cotton fields, on the basis of a standardized trapping strategy, that can take into account a wide range of factors, such as trap design and trap height. [ABSTRACT FROM AUTHOR]

Oviposition deterrents are the info-chemicals that modifies the behavior of conspecific female insects either to settle on the treated surface or to lay eggs thereafter, reducing intra-specific competition. Drawing from our prior research, it has been established that the fatty acids (Oleic and linoleic acid) found in vegetable oils exhibit properties of oviposition deterrence. The present study was designed to investigate the oviposition deterrent activity of vegetable oils against pink bollworm. Six different vegetable oils, namely groundnut, sunflower, soybean, rice bran, safflower and sesame containing oleic and linoleic acid as major fatty acids were selected and evaluated under laboratory and field conditions. Under laboratory conditions, oils were tested at concentrations ranging from 0.5 to 3.0%, with methanol as control. Cotton twigs with squares served as the oviposition substrate and the total number of eggs laid by the moth was counted and compared to control. The results demonstrated a significant reduction in number of eggs laid as evident from the avoidance index (AI) and percent effective deterrence (PED) values of vegetable oil treatments. Descending order of oviposition deterrent efficacy as revealed from AI and PED values, groundnut (AI = 0.74, PED = 84.40%) > soybean (0.67, 79.87%) > sesame (0.65, 78.59%) > sunflower (0.59, 74.09%) > rice bran (0.57, 71.93%) > safflower (0.55, 71.09%). Our findings were further validated through field studies conducted during 2019–2020 and 2020–2021, confirming effectiveness of the selected vegetable oils in reducing the boll damage. Study demonstrates the promising oviposition deterrent effect of vegetable oils against Pectinophora gossypiella and hold great potential as an eco-friendly component in integrated pest management program of cotton. [ABSTRACT FROM AUTHOR]

An experiment was conducted at the Department of Cotton, Tamil Nadu Agricultural University, Coimbatore to evaluate the field efficacy of an egg parasitoid, Trichogrammatoidea bactrae Nagaraja through inundative releases against Pectinophora gossypiella (Saunders) in cotton for two successive field trials during Kharif 2021 and 22. The parasitisation efficacy of T. bactrae was tested in the cotton ecosystem and the results revealed that the parasitism on the eggs was found be on par with that observed with NSKE 5% concentration (24.63%), neem formulation 1500 ppm 1% concentration (24.10%), Pongamia extract 5% concentration (23.13%), Jatropha extract 5% concentration (23.93%) and were found the safest to T. bactrae. The emamectin benzoate 5 SG at 190g/ ha (19.49%) and clorantraniliprole 18.5 SC at 150 mL/ha (15.26%) were on par with each other. Results suggested that among the insecitcides tested emamectin benzoate 5 SG and chlorantraniliprole 18.5 SC were safer to T. bactrae and inundative release of T. bactrae can achieve sizeable control of P. gossypiella, hence it can be integrated with other components for IPM. [ABSTRACT FROM AUTHOR]

A field study assessed the efficacy of insecticides against pink bollworm of cotton. Spinosad 45SC treated cotton had the lowest infestation at 23.95% in the first spray, while cypermethrin 25EC had a 26.06% infestation in the second spray. Emamectin benzoate 5SG and spinosad 45SC were the most potent insecticides for locule damage reduction. Emamectin benzoate 5SG had 70.54% mortality in the first spray, while spinosad 45SC had 76.2% mortality in the second spray. Emamectin benzoate 5SG, spinosad 45SC, and cypermethrin 25EC were the most effective insecticides overall. [ABSTRACT FROM AUTHOR]

Background: Pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) has become a potential pest of cotton by causing substantial yield losses around the world including Pakistan. Keeping in view the facts like limited research investigations, unavailability, and high cost of artificial diet's constituents and their premixes, the present research investigations on the dietary aspect of P. gossypiella were conducted. The larvae of P. gossypiella were reared on different diets that were prepared using indigenous elements. The standard/laboratory diet comprised of wheat germ meal 34.5 g, casein 30.0 g, agar–agar 20.0 g, sucrose 10.0 g, brewer's yeast 5.0 g, α-cellulose 1.0 g, potassium-sorbate1.5 g, niplagin 0.5 g, decavitamin 0.01 g, choline-chloride 0.06 g, maize-oil 3.30 g, honey 2.0 g, and water 730.0 mL. Alternatives to cotton bolls and wheat germ meal were okra seed sprouts, okra fruit, cottonseed meal, and okra seed meals, which were included in the study to introduce an efficient and economic mass-rearing system. Results: The larval development completed in 19.68 d ± 0.05 d with a weight of 20.18 mg ± 0.20 mg at the fourth instar fed on the cottonseed meal-based diet instead of wheat germ meal based diet. On the same diet, 84.00% ± 4.00%, 17.24 mg ± 0.03 mg, and 7.76 d ± 0.06 d were recorded as pupae formation, pupal weight, and pupal duration, respectively. Adult emergence, 76.00% ± 1.00% was recorded from pupae collected from larvae raised on cottonseed meal-based diet. These male and female moths lived for 40.25 d ± 0.10 d, and 44.34 d ± 0.11 d, respectively. Females deposited 21.28 ± 0.04 eggs per day with the viability of 65.78% ± 0.14%. The larval mortality at the fourth instar was 37.20% ± 1.36% and malformed pupation of 12.00% ± 1.41% was recorded. Replacement of wheat germ meal with that of local meals (cottonseed and okra seed) in the standard laboratory diet has saved 463.80 to 467.10 PKR with 1.62 to 1.63 cost economic returns, respectively. Conclusion: This research is of novel nature as it provides a concise and workable system for the economic and successful rearing of P. gossypiella under laboratory conditions. [ABSTRACT FROM AUTHOR]

A laboratory experiment was conducted to study the biology of pink bollworm Pectinophora gossypiella (Saunders) on cotton at four different temperature levels. It was found that males have a considerably shorter total life cycle duration on cotton at 35±1°C (29.5 days) followed by 30±1°C (37.2 days), 25±1°C (46.9 days) and highest at 20±1°C (50.8 days). Similarly, minimum total life cycle duration of female P. gossypiella was recorded at 35±1°C (30.2 days) followed by 30±1°C (38.0 days), 25±1°C (47.3 days) and maximum at 20±1°C (51.7 days). The highest fecundity was observed at 30±1°C (106.2) followed by 25±1°C (100.1), 35±1°C (60.1) and lowest at 20±1°C (55.2). Male as to female sex ratio was highest at 35±1°C (1:1.5) followed by 25±1°C (1:1.4), 30±1°C (1:1.3) and lowest at 20±1°C (1:1.2). These findings revealed that variation in temperature significantly influences the life cycle duration, fecundity and sex ratio of pink bollworms on cotton, with higher temperatures accelerating development and enhancing reproductive success. [ABSTRACT FROM AUTHOR]

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Abstract Background The cryptic nature of pink bollworm Pectinophora gossypiella (Saunders) larvae enables its reduced vulnerability to insecticidal control. Further, the development of resistance against Bacillus thuringiensis (Bt) toxins posed a serious threat to transgenic cotton cultivation. This necessitated determining the critical timing of spray applications on the control effectiveness. This study assessed the influence of egg age (freshly laid vs. three-day-old) and the location of larvae (directly exposed to the insecticide residues on the boll rind vs. burrowed inside the bolls) on insecticide control efficacy. Results The results revealed a significant decrease in the ovicidal activity of tested insecticides with an increase in the age of eggs from one day old to three days old (paired t-test, P 80% mortality) than the larvae exposed after they had burrowed inside the bolls (

Background: The cryptic nature of pink bollworm Pectinophora gossypiella (Saunders) larvae enables its reduced vulnerability to insecticidal control. Further, the development of resistance against Bacillus thuringiensis (Bt) toxins posed a serious threat to transgenic cotton cultivation. This necessitated determining the critical timing of spray applications on the control effectiveness. This study assessed the influence of egg age (freshly laid vs. three-day-old) and the location of larvae (directly exposed to the insecticide residues on the boll rind vs. burrowed inside the bolls) on insecticide control efficacy. Results: The results revealed a significant decrease in the ovicidal activity of tested insecticides with an increase in the age of eggs from one day old to three days old (paired t-test, P < 0.05). The larvae directly exposed to the insecticide residues on the boll rind were more susceptible (> 80% mortality) than the larvae exposed after they had burrowed inside the bolls (< 49% mortality). The inhibitory effects of tested insecticides on developmental biology were more pronounced in the experiment on pre-larval release insecticide treatment compared with insecticide treatment given post-larval release and entry inside the bolls. Conclusion: Egg age influences the insecticide susceptibility, as does the larval location, directly exposed vs burrowed inside the bolls. Older eggs and the larvae that had burrowed inside the green bolls of cotton were relatively less susceptible to the insecticide treatments. The toxic effects of insecticides on egg and larval stages were primarily ephemeral. These findings are significant for devising a comprehensive strategy for pink bollworm management on a sustainable basis. [ABSTRACT FROM AUTHOR]

Population fluctuations of Aphis gossypii, Chloridea virescens, Anthonomus vestitus, Dysdercus peruvianus and Pectinophora gossypiella, besides their natural enemies were studied during the entire phenological period of a Tangüis cotton crop at La Molina (Lima), using three sampling techniques: direct plant evaluation, plant shake falls and pitfall traps. A. gossypii was the most abundant pest, being more important in the vegetative development, followed by D. peruvianus and P. gossypiella, both with greater importance in the fructification stage. Predatory insects and spiders were recorded during the whole crop period, where the most frequent were, in predatory insects Hippodamia convergens, Hyalochloria denticornis and Rhinacloa forticornis, and in spiders Misumenops sp. morpho 1, Zelotes laetus and Theridion volubile. Parasitoidism was low or scarce in most of the pests, highlighting Lysiphlebus testaceipes as A. gossypii parasitoid due to its abundance in the vegetative development of the cotton field. [ABSTRACT FROM AUTHOR]

The evolution of pest resistance to insecticidal proteins from Bacillus thuringiensis (Bt) restricts the sustainable application of transgenic Bt crops, and exploring other ecofriendly insecticides to efficiently suppress Bt‐resistant populations is thus urgently needed. The plant secondary metabolite rutin possesses pest resistance effects and plays an important role in plant resistance to pests, but the effect of rutin on pink bollworms is unclear. We investigated the effects of rutin on two types (Bt‐susceptible and Bt‐resistant) of pink bollworms (Pectinophora gossypiella). Rutin had significant inhibitory effects on the growth, development, and oviposition of both Bt‐susceptible and Bt‐resistant strains. For both strains, rutin ingestion by larvae did not significantly affect larval survival at 7 days after treatment or egg hatching rate but significantly decreased pupation rate, eclosion rate, neonate‐to‐adult survival, pupal weight and eggs per female and significantly prolonged larval developmental periods, and the effect increased with increasing rutin content. The response to rutin ingestion was basically consistent between Bt‐resistant and Bt‐susceptible strains, indicating that the Bt‐resistant strain did not exhibit cross‐resistance to rutin. These results provide a reference basis for green control and resistance management of pink bollworms and may be used as a component of comprehensive management for this pest. [ABSTRACT FROM AUTHOR]

The pink bollworm, Pectinophora gossypiella (Saund.) is an important pest that causes severe economic loss for cotton crop. The potent bioactive properties of three tested compounds; the two IGRs compounds; Dimilin (Diflubenzuron) and Nomolt (Teflubenzuron), and the bio-pesticide compound Emacte (Emamectin benzoate); were tested against two different ages of P. gossypiella eggs under laboratory conditions of 26±1°C and 70±5% RH. Results revealed that older eggs of P. gossypiella are more susceptible to pesticides than the younger ones where LC50 values were 155.4, 185.85, and 1.95 ppm. for 0-1-day-old eggs, while decreased to 81.42, 103.42, and 1.30 ppm, for 2-3 days-old eggs in Dimilin, Nomolt, and Emacte treatments, respectively. The incubation periods for eggs were prolonged as a result of the treatments, in comparison to the untreated check. In addition, the estimated developmental periods for the immature stages increased to 19.6, 17.9 and15.85 days for larva and 12.5, 11.8, and 9.76 days for pupa, in treatment of 0-1 day old eggs and to 20.2, 18.8, and 16.9 days for larva and 13.6, 11.98 and 10.36 days for pupa in treatment of 2-3 days old eggs in Dimilin, Nomolt and Emacte treatments respectively, compared to 14.55 days for larval stage and 8.03 days for pupal stage in the untreated. The present study noted also, light changes in the levels of the total protein, carbohydrate and chitin composition during embryogenesis for P. gossypiella eggs as a result of treatments in comparison to the untreated. [ABSTRACT FROM AUTHOR]

Pink bollworms severely affect the production of cotton. The method currently used for pink bollworm control is the planting of Bt (Bacillus thuringiensis) protein-expressing transgenic cotton. However, pink bollworms can develop strong resistance to Bt proteins in transgenic cotton because of the large planting area and long planting time of this crop, which severely affects the control of pink bollworms. Intestinal microorganisms play very important roles in insect growth, development and Bt resistance. However, the effect of intestinal microorganisms on pink bollworm Bt resistance is still unclear. The current study aimed to analyze the effect of intestinal microorganisms on the Bt resistance of pink bollworms. Intestinal microorganisms associated with Bt resistance were initially screened through Illumina MiSeq sequencing and analysis. The results showed that feeding with a mixture of gentamicin, Cry1Ac and an artificial diet could significantly increase the mortality of pink bollworm larvae compared with feeding with of a mixture of Cry1Ac and an artificial diet or an artificial diet alone. The microbial diversity, community structure and composition of the pink bollworm larval intestine were significantly influenced by feeding with a mixture of gentamicin, Cry1Ac and an artificial diet. Several intestinal bacteria with significantly altered abundances after treatment with gentamicin were preliminarily screened as potential resources for addressing Bt toxicity. This study provides useful strategies for addressing the Bt resistance of pink bollworms. [ABSTRACT FROM AUTHOR]

The pink bollworm, Pectinophora gossypiella (Saunders) is a key pest of cotton accounting for yield losses to the level of 20-90% and has recently emerged as a serious concern for cotton production in India. Accurately determining optimal trap height for sex pheromone-baited traps in the field is vital for maximizing male pink bollworm moth capture. This knowledge enhances pest management, leading to improved crop yields and reduced economic losses. This study focuses on assessing the most effective trap height for capturing pink bollworm moths, with significant implications for pest management practices and agricultural productivity. During both the years 2021-22 and 2022-23, our findings demonstrate that pheromone traps installed at canopy level achieved the highest moth captures (30.87 and 28.13 moths/trap/week, respectively). Notably, traps positioned 15 cm above the canopy level yielded statistically comparable results (20.15 and 17.98 moths/trap/week, respectively) as compared to traps placed 15 cm below the canopy (19.44 and 16.99 moths/trap/week, respectively). [ABSTRACT FROM AUTHOR]

Pink bollworm (Pectinophora gossypiella) is one of the most notorious insects causing severe damage to cotton crops thought the world. A huge amount of different chemical formulations have been used for the control of P. gossypiella population that affects its biology. The present research was executed to determine the influence of insecticides on adult fecundity and boll damage potentials by the larvae. The results elucidated that a mixture of Deltamethrin+Triazophos had a maximum impact in fecundity reduction and boll damage by the larva when tested at one, three and twenty-four hours of post-application intervals (PAIs). The damage to cotton bolls was in the ranges of 27.50±0.57 to 57.50±1.44% at 3 to 144-hours PAIs respectively. Damage to cotton bolls and reduction in fecundity was at the highest 82.50±1.34, and 49.65±1.51% when a mixture of Deltamethrin+Triazophos and Alpha-Cypermethrin were applied at 144-hours PAI respectively. The experimental results highlighted the critical efficacy of the test insecticide for the control of P. gossypiella by reducing the boll damage and oviposition at different intervals of application. [ABSTRACT FROM AUTHOR]

Background: The emergence of pink bollworm (PBW), Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), in cotton due to Bt resistance and concealed feeding habit has created a need for alternative, eco-friendly, and cost-effective control methods. This study aimed to evaluate the bio-efficacy and reproductive potential of two native strains of entomopathogenic nematodes (EPNs), Heterorhabditis indica, namely CICR-HI-CL and CICR-HI-MN, against PBW larvae and pupae under in-vitro conditions. Results: The larval assay revealed that strain CICR-HI-CL exhibited higher potency than strain CICR-HI-MN against 2nd, 3rd, and 4th instar larvae, with median lethal dose (LD50) values of 5.45, 4.45, and 4.60 infective juveniles (IJs) per larva, respectively. In case of pupal bioassay, both EPN strains demonstrated greater virulence when applied directly (LD50 values: 29.65 and 73.88 IJs per pupa for strains CICR-HI-CL and CICR-HI-MN, respectively) compared to soil application (147.84 and 272.38 IJs per pupa). Both EPN strains successfully penetrated and reproduced on 4th instar larvae, resulting in maximum production of 19.28 and 20.85 lakh IJs per larva in the next generation when inoculated at 30 IJs per larva. Conclusion: The present study has generated useful information on the virulence and reproductive potential of two strains of EPN H. indica (CICR-HI-CL and CICR-HI-MN) against PBW, a dreaded pest of cotton. Higher virulence and reproductive potential of EPN strains demonstrated their ability to multiply, sustain and perpetuate on larval and pupal stages of PBW. The knowledge generated will help formulate effective management strategies for PBW with the inclusion of EPN as a potential biological control candidate. The soil-dwelling life stages viz., last instar hibernating larvae and pupae of PBW can be the ideal weak links to make a successful use of H. indica for sustainable management of PBW in the cotton ecosystem. However, before taking these EPN strains to field for managing PBW, detailed studies investigating their biocontrol potential against PBW under field conditions are needed. [ABSTRACT FROM AUTHOR]

Pink bollworm (PBW), Pectinophora gossypiella is one of the major pests of cultivated cotton around the globe. Most of the attempts to control this pest by using chemical insecticides in crops have led to the evolution of numerous problems. Hence a suitable tool that addresses the problem will be a plausible way to manage the pest. The use of natural enemies may represent an effective alternative management tactic. Here, we study the parasitization potential of Bracon hebetor on different larval instars of P. gossypiella under laboratory condition. The release of B. hebetor at 30:50 (PBW larvae: parasitoid) and 30:40 ratios resulted in significantly higher level of parasitization on PBW larvae (85.8–94.2% in 2nd instar, 99.2–100% in 3rd instar and 100% in 4th instar of PBW) than with 30:30, 30:20 or 30:10 (PBW larvae: parasitoid) ratio (40.0–63.3% in 2nd instar, 47.5–78.3% in 3rd instar and 50.8–80.8% in 4th instar of PBW), respectively. Similarly, the survival of B. hebetor eggs demonstrated positive results, with up to 89.2% of parasitoid adults emerging from second-instar larvae when released in a ratio of 30:10. Additionally, on fourth-instar larvae, parasitoid emergence rates of 93.7% and 93.9% were observed for ratios of 30:10 and 30:20, respectively. This data indicates the host's suitability and the parasitoids high survivability. Lower number of eggs per larva was found to support a better survival of the parasitoid, with eggs ranging from 3.1 to 12.8 eggs per larvae and emergence of 7.9 to 93.9% at different ratios on all instars of PBW. The outcome of the present investigation is promising and suggests the parasitization and survival of B. hebetor is sufficient enough to manage the pest under controlled conditions and it is possibly an excellent candidate for augmentative biological control of PBW under field condition. [ABSTRACT FROM AUTHOR]

The pink bollworm incidence and adult male moth trap catches were monitored throughout the cropping period for four years from 2017-2021 on Bt cotton (KCH-14K59) at the University of Agricultural Sciences, Raichur. The pink bollworm male moth activity (95 moths/trap) was higher during the month of December month (49th SMW) with the highest larval incidence (25.67 larvae / 20 bolls) on green bolls during the month of February (6th - 9th SMW). The correlation matrix indicating the relationship between the weekly mean moth catches, larval incidence and meteorological variables from 2017 to 2021 exerted negative association with the mean of maximum and minimum temperature, rainfall, morning and afternoon relative humidity. However, the influence of all these whether parameters was found to be highly significant. When the data was subjected to Multi Linear Regression analysis, the results revealed that 78.70 per cent of mean pheromone trap catches (R2 = 0.787) and 92 per cent of mean larval incidence (R² = 0.92) were negatively influenced by minimum temperature. [ABSTRACT FROM AUTHOR]

In order to develop integrated management approaches for Pectinophora gossypiella, basic studies are crucial. The two-sex life table is the most important tool for describing the fitness and population parameters of both sexes (male and female) of an insect, while the traditional life table only explains the female sex of an insect. However, no study has reported on the biology of P. gossypiella using two-sex life table tools. Therefore, this study explains the rearing dynamics of P. gossypiella on a cotton seed-based artificial diet and a natural diet (mature cotton bolls). According to the results, the oviposition period of P. gossypiella was recorded to be longer on the artificial diet (9.07 ± 0.24) compared to the natural diet (7.40 ± 0.11). The total fecundity of P. gossypiella was greater on the artificial diet (125.94 ± 3.06) in comparison to the natural diet (60.37 ± 1.10). The population parameters, including intrinsic rate of increase, finite rate of increase, gross reproductive rate, and net reproductive rate of P. gossypiella were highest on the artificial diet in comparison to the natural diet. This study concluded that the cotton seed-based artificial diet was most suitable for the rearing of P. gossypiella. In the future, P. gossypiella may be studied in depth in light of the findings in this study. [ABSTRACT FROM AUTHOR]

This paper reviews the ongoing failure of hybrid transgenic Bt (Bacillus thuringiensis) cotton unique to India. The underlying cause for this failure is the high cost of hybrid seed that imposes a suboptimal long-season low plant density system that limits yield potential and has associated elevated levels of late-season pests. Indian hybrid Bt cotton production is further complicated by the development of resistance to Bt toxins in the key pest, the native pink bollworm (Pectinophora gossypiella Saunders, PBW), resulting in increased insecticide use that induces ecological disruption and outbreaks of highly destructive secondary pests. Rainfed cotton production uncertainty is further exacerbated by the variable monsoon rains. While hybrid cotton produces fertile seed, the resulting plant phenotypes are highly variable preventing farmers from replanting saved seed, forcing them to buy seed yearly (i.e., market capture), and effectively protecting industry Intellectual Property Rights (IPRs). The lessons gained from the ongoing market failure of hybrid Bt cotton in India are of utmost importance to its proposed introduction to Africa where, similar to India, cotton is grown mainly in poor rainfed smallholder family farms, and hence similar private–corporate conflicts of interest will occur. Holistic field agroecological studies and weather-driven mechanistic analyses are suggested to help foresee ecological and economic challenges in cotton production in Africa. High-density short-season (HD-SS) non-hybrid non-genetically modified irrigated and rainfed cottons are viable alternatives for India that can potentially produce double the yields of the current low-density hybrid system. [ABSTRACT FROM AUTHOR]

Pectinophora gossypiella (Saunders) is a potential threat for the successful cultivation of cotton all over the world. Despite the use of modern management strategies, the damage caused by this pest is increasing. The repeated exposure of this pest to Bacillus thuringenisis (Bt) crops resulted in resistance development, which has threatened the continued success of Bt cotton cultivation. Salicylic acid has been reported to enhance the efficiency of crops. The present study was carried out to determine the effect of salicylic acid on the oviposition (pre-oviposition and post-oviposition time) and feeding behavior (pre-feeding time and post-feeding time) of pink bollworm larvae in two cotton varieties, i.e., CIM-70 and NIAB-78. In the first experiment, leaves and bolls treated with different concentrations of salicylic acid were kept in an oviposition chamber and adults were released in a chamber with a ratio of 5:5 males to females, respectively. The experiment was performed following a Completely Randomized Design (CRD) with three replications and six concentrations of salicylic acid (0, 10, 20, 40, 80, and 160 ppm). In a second complementary experiment, salicylic acid was evaluated against feeding behavior, i.e., larval duration, pre-feeding time, feeding time, post-feeding time, and percentage mortality of pink bollworm. In both experiments, the results revealed that the application of salicylic acid at a maximum concentration was effective against the oviposition and feeding of pink bollworm only in the NIAB-78 cultivar. It is concluded that salicylic acid has the potential to reduce pink bollworm risks, and the present investigation will help researchers as well as farmers plan for the timely sustainable management of pink bollworm. [ABSTRACT FROM AUTHOR]

The widespread adoption of genetically modified (GM) crops, particularly Bt cotton expressing Cry1Ac and Cry2Ab toxins, has revolutionized global agriculture by providing effective solutions to pest-related challenges. However, the Pink Bollworm, Pectinophora gossypiella, a highly destructive insect pest threatening cotton cultivation worldwide, has developed resistance to Bt cotton, leading to reduced benefits. This study aimed to assess the relative response of Pink Bollworm population collected from different regions in South India to Bollgard-II® Bt cotton expressing both Cry1Ac and Cry2Ab toxins. Field populations of Pink Bollworm were collected from major cotton-growing areas in Karnataka (Raichur, Dharwad and Yadgir), Tamil Nadu (Jolarpet) and Gujarat (Vadodara), while a laboratory-susceptible population served as a reference. The results showed that pink bollworm populations from various locations exhibited different levels of resistance to Bollgard-II® Bt cotton. Median lethal concentration (LC50) values for field populations ranged from 0.790 to 1.011 ppm, indicating reduced susceptibility compared to the susceptible laboratory colony (LC50 = 0.011; χ² = 0.829; df = 3; h = 0.414). The highest resistance ratio (RR) of 91.90 was recorded in the population collected from Vadodara (LC50= 1.011; χ² = 2.461; df=3; h= 0.820), followed by Raichur (RR = 90.63; LC50 = 0.997; χ² = 7.523; df = 3; h = 2.509), Yadgir (RR = 89.63; LC50 = 0.986; χ² = 3.862; df =3; h = 1.288) and Dharwad (RR = 84.64; LC50 = 0.931; χ² = 5.334; df =3; h = 1.781). The population collected from Jolarpet (LC50 = 0.790; χ² = 3.815; df = 3; h = 1.272) showed resistance ratio of 71.81, lowest among the populations tested. These findings highlight the increased resistance of pink bollworm to the combined Cry1Ac and Cry2Ab toxins in Bollgard-II® Bt cotton, indicating the need for careful management strategies to delay further resistance development. These results emphasize the importance of sustainable agricultural practices to overcome the challenges posed by insect pests in GM crop cultivation. [ABSTRACT FROM AUTHOR]

The impact of trap type and height on the captures of adults of the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), was assessed in cotton fields in three experimental sites (Nikaia, Nees Karyes, and Koilada) in Central Greece. Initially, the effectiveness of three different traps (white Delta, red Delta, and green Funnel) was compared. Subsequently, white Delta traps were positioned at three heights, i.e., 30, 60, and 90 cm, above ground level. Overall, captures notably increased in all traps from late July to mid-September. Funnel traps had poor performance for the captures of P. gossypiella adults, as compared with the respective figures for the other two Delta traps. Specifically, in two experimental sites (Nikaia and Koilada), both Delta traps cumulatively captured significantly more adults than the Funnel trap throughout the monitoring period. In the third site (Nees Karyes), the red Delta trap captured in total significantly more adults than the other two tested traps. Moreover, we found that traps in Nikaia placed at 90 cm captured significantly less adults as compared with the other two trap heights. The same trend was observed in Koilada; however, differences were significant only between traps at 30 and 90 cm. No significant differences were determined among different heights in the third site (Nees Karyes). These findings offer valuable insights for the monitoring protocols of P. gossypiella in cotton fields, on the basis of a standardized trapping strategy, that can take into account a wide range of factors, such as trap design and trap height.

The pink bollworm incidence and adult male moth trap catches were monitored throughout the cropping period for four years from 2017-2021 on Bt cotton (KCH-14K59) at University of Agricultural Sciences, Raichur. The pink bollworm male moth activity (95 moths/trap) was more during the month of December month (49th SMW) with the highest larval incidence (25.67 larvae/ 20 bolls) on green bolls during the month of February (6th - 9th SMW). The correlation matrix indicating relationship between the weekly mean moth catches, larval incidence and meteorological variables from 2017 to 2021 exerted negative association with mean of maximum and minimum temperature, rainfall, morning and afternoon relative humidity. However, the influence of all these whether parameters was found to be highly significant. When the data was subjected to Multi Linear Regression analysis, the results revealed that 78.70 per cent of mean pheromone trap catches (R2 = 0.787) and 92 per cent of mean larval incidence (R2 = 0.92) was negatively influenced by minimum temperature.

The pink bollworm (Pectinophora gossypiella) is one of the world's most destructive pests of cotton. This invasive lepidopteran occurs in nearly all cotton-growing countries. Its presence in the Ord Valley of North West Australia poses a potential threat to the expanding cotton industry there. To assess this threat and better understand population structure of pink bollworm, we analysed genomic data from individuals collected in the field from North West Australia, India, and Pakistan, as well as from four laboratory colonies that originated in the United States. We identified single nucleotide polymorphisms (SNPs) using a reduced-representation, genotyping-by-sequencing technique (DArTseq). The final filtered dataset included 6355 SNPs and 88 individual genomes that clustered into five groups: Australia, India-Pakistan, and three groups from the United States. We also analysed sequences from Genbank for mitochondrial DNA (mtDNA) locus cytochrome c oxidase I (COI) for pink bollworm from six countries. We found low genetic diversity within populations and high differentiation between populations from different continents. The high genetic differentiation between Australia and the other populations and colonies sampled in this study reduces concerns about gene flow to North West Australia, particularly from populations in India and Pakistan that have evolved resistance to transgenic insecticidal cotton. We attribute the observed population structure to pink bollworm's narrow host plant range and limited dispersal between continents. [ABSTRACT FROM AUTHOR]

Since 2002, transgenic crops that produce Cry1Ac and Cry2Ab toxins have been used in India to control bollworms. From 2002 to 2009, Bt-cotton effectively controlled the pink bollworm (PBW). However, since 2009 numerous studies have reported high survival of PBW on Bt-cotton expressing Cry1Ac and Cry2Ab toxins, indicating reduced susceptibility to Cry toxins expressed in Bt-cotton. In the current study, we attempted to estimate the frequency of resistance alleles to Cry1Ac and Cry2Ab toxins in a field collected population of pink bollworms from Andhra Pradesh. Resistance allele frequency was estimated using an F2 screen methodology for the first time after 17 years of Bt-cotton cultivation. Our study finds that the allele frequency for Cry1Ac is 0.082 and for Cry2Ab is 0.054, with a detection probability of greater than 97%. In our survey conducted in 2018–19 and 2019–20, we also noticed high survival and damage by PBW on Bt-cotton expressing Cry1Ac and Cry2Ab. Our survey report reveals, > 30% flower damage, > 90% green boll damage and > 80% locule damage by PBW on Bt-cotton expressing Cry1Ac and Cry2Ab toxins. [ABSTRACT FROM AUTHOR]

Background: During field surveillance in Gujarat, India, in 2009, scientists found that pink bollworm was surviving in the first generation of Bollgard cotton, which contains a single protein. This survival was observed in four districts of Gujarat. From 2012 to 2014, surveys revealed that pink bollworm larvae had higher survival rates on Bollgard II cotton in Amreli and Bhavnagar districts. In 2016, a pink bollworm outbreak in Maharashtra caused significant losses in cotton production, leading to damage, yield losses, and increased management costs in several regions. The objective of the present study was to determine the reaction of Pectinophora gossypiella to Cry1Ac and Cry2Ab toxins. Results: Neonates of P. gossypiella collected from six distinct locations in Vidarbha were subjected to seven different concentrations of Cry1Ac. The highest LC50 value was recorded in the population collection of Yavatmal (1.362 μg/ml diet) but the lowest LC50 value of 0.600 μg/ml diet in Buldana population. The highest MIC50 value was recorded in the population collected from Yavatmal (0.743 μg/ml diet) and the lowest MIC50 value of 0.413 μg/ml diet in the Buldana population (0.431 μg/ml diet). The highest IC50 value was recorded in the population collected from Yavatmal (0.303 μg/ml diet) but the lowest IC50 value of 0.127 μg/ml diet in the Buldana population. Neonates of P. gossypiella collected from six different locations in Vidarbha were exposed to seven different concentrations (9.0, 3.0, 1.0, 0.333, 0.111, 0.037 and 0.012 for Cry1Ac and 27.0, 9.0, 3.0, 1.0, 0.333, 0.111 and 0.037 μg/ml for Cry2Ab) which revealed that the Yavatmal population had the highest LC50 value of 94.294 μg/ml diet and the lowest LC50 value was recorded in the Amravati population (42.144 μg/ml diet). The highest MIC50 value of 27.258 μg/ml diet was recorded in Buldana population, but the lowest MIC50 value was recorded in the Amravati population (12.881 μg/ml diet). The highest IC50 value of 3.209 μg/ml diet was observed in Yavatmal population, and the lowest one was recorded in the Amravati population (1.574 μg/ml diet). Conclusions: According to the LC50 values, all of the P. gossypiella populations in Vidarbha were extremely insensitive and had field-evolved resistance to the Bt proteins found in the transgenic cotton varieties of Bollgard II. [ABSTRACT FROM AUTHOR]

Background: After the commercialization of insect-resistant transgenic Bt cotton Bollgard I & II, India ranks first in the world in cotton production. Cotton insecticide consumption was drastically reduced as nearly 95% of the cotton area was replaced with Bollgard II. However, the benefits of transgenic cotton appear to have been diminished as the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) developed field resistance to Cry1Ac expressing Bt cotton in India in 2008. In 2015, there was an unusual survival of P. gossypiella on Bollgard II cotton in some parts of Gujarat and Maharashtra, which is a cause for concern. Results: In the present study, PCR analysis and gel visualization of BGII resistant field population of P. gossypiella showed that the presence of r1, r2, r3, r1s, r2s, r3s, and ss mutated cadherin alleles, which produced amplicon sizes of 750 bp, 700 bp, 730 bp, 12,700 bp, 750 bp, 980 bp, 600 bp and 1600 bp, respectively, when seven different types of cadherin allele(s) specific primers were used. The r1 mutant allele was detected in Amaravati, Wardha, Yavatmal, and Nagpur, but not in Akola and Buldhana, using primers r1disfor and Int-540. The r2 mutant allele was detected in Akola, Wardha, and Nagpur, but not in Buldhana, Amaravati, and Yavatmal, using primers r2disback and Cad2366. The r3 mutant allele was detected in all locations using primers r3disback and Cad3221. Amplicons of sizes 750 bp, 700 bp and 730 bp were obtained for r1, r2, and r3 mutant alleles, respectively. The sizes of the amplicons were 1270 bp for r1s, 750 bp for r2s, and 980 bp for r3s.The absence of bands for r1, r2, and r3 cadherin alleles in individuals indicated the possibility of having the ss allele, which was confirmed using primers Cad3324 and Int-651. The presence of ss mutant allele was observed in field-collected P. gossypiella populations from BG II cotton in various locations, with a 600 bp and 1600 bp size amplicons produced using the same primers. Conclusions: PCR analysis revealed the presence of r1, r2, r3, r1s, r2s, r3s, and ss mutated cadherin alleles in field-collected populations of Vidarbha which provide evidence to field-evolved resistance of P. gossypiella to BGII cotton. [ABSTRACT FROM AUTHOR]

Cotton varieties that are high yielding and resistant to pests are required to improve production and productivity and to capitalize on the crop's enormous potential and its critical role in Ethiopia's expanding textile industry. Lack of improved cotton technology has forced farmers to recycle local varieties for ages which have become very susceptible to pests which are the major causes of very low productivity and quality of cotton in the country. Among major pests, bollworms (Helicoverpa armigera and Pectinophora gossypiella) account for 36–60% of yield losses. In the absence of genetically resistant or tolerant varieties, genetically engineered bollworm-resistant Bacillus thuringiensis (Bt) cotton has offered a great opportunity to reduce crop losses from bollworms. The objective of the study was to evaluate the efficacy of bollworm resistance and adaptability of Bt cotton varieties across cotton growing environments in Ethiopia and provide recommendations. Two Bt cotton hybrids (JKCH 1947 and JKCH 1050), one Bt OPV (Sudan), and three OPV conventional varieties (Weyito 07, Stam-59A, and Deltapine-90) were evaluated at seven different agro-ecologies using a randomized complete block design (RCBD) with three replications. Results showed significant differences among genotypes for yield and other traits. Hybrids JKCH 1947 and JKCH 1050 were the top high yielders under high and mild bollworm infestations, with mean seed cotton yield of 3.10 t·ha−1 each and lint yield of 1.20 and 1.19 t·ha−1, respectively, whereas the standard check Deltapine-90 (popular variety) recorded a mean seed cotton and lint yield of 2.3 t·ha−1 and 0.8 t·ha−1, respectively. Combined analysis showed that genotypes, environment, and the genotypes × environment interactions had a highly significant effect (P < 0.05) on fiber quality. Weyito 07 and the two hybrids (JKCH 1947 and JKCH 1050) had upper half mean fiber lengths in the range of 27.78 to 32.11 mm. For fiber strength, genotypes Weyito 07, JKCH 1050, Stam-59A, and JKCH 1947 had 33.50 g/tex, 28.59 g/tex, 28.00 g/tex, and 27.75 g/tex, respectively. The fiber quality values of the hybrids were within acceptable limits, with staple lengths ranging from 27.78 to 28.44 mm and fiber strengths ranging from 27.75 to 28.59 g/tex. Results show potential adaptation of the hybrids under different cotton growing environments and their superior yield performance due also to added protection of yield losses from damage by bollworms. The contrast is bigger under high insect pressure conditions due to the genetically engineered Bt trait compared to the conventional varieties. The effective field resistance against bollworms in most locations shows that wider use of these hybrids can enhance cotton productivity and quality in Ethiopia. [ABSTRACT FROM AUTHOR]

Pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) is an important pest of cotton worldwide; causing significant economic loss to cotton growers. Its control under field condition is difficult, as it remains inside the boll and feeds internally. Therefore, under this study we have evaluated different insecticides viz., Quinalphos 25% EC, Profenofos 50% EC, Thiodicarb 75% WP, Chlorantraniliprole 18.5% SC, Spinosad 45% SC, Neem oil (0.3% W/W), Cypermethrin 25% EC, Triazophos 40% EC, Deltamethrin 2.8% EC and the combination of Profenofos 40% + Cypermethrin 4% EC and Deltamethrin 1% + Triazophos 35% EC for the management of P. gossypiella in cotton under rainfed conditions. The results revealed that combination of Profenofos 40% + Cypermethrin 4% EC showed most effective and offered lowest number of exit holes (0.3 to 0.5), mines on epicarp (2.0 to 7.0), larvae/plant (0.3 to 1.0) and per cent locule damage (1.3 to 7.3%) in green bolls as compared to individual formulations. Among individual formulations, Cypermethrin 25% EC effectively controlled pink bollworm larval damage (0.3 to 1.1 exit holes, 3.3 to 4.0 mines on epicarp, 0.9 to 1.7 larvae and 1.3 to 13.0% locule damage in green bolls after 10 days of spray) as compared to other treatments. Further, maximum seed cotton yield was recorded (11.6 to 12.04 q/ha) in Profenofos 40% + Cypermethrin 4% EC treated fields. The integration of these insecticide molecules proved to be effective in the management of pink bollworm under field conditions. [ABSTRACT FROM AUTHOR]

The pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), is a major global pest of cotton. Current management practices include chemical insecticides, cultural strategies, sterile insect releases, and transgenic cotton producing crystalline (Cry) protein toxins of the bacterium Bacillus thuringiensis (Bt). These strategies have contributed to the eradication of P. gossypiella from the cotton-growing areas of the United States and northern Mexico. However, this pest has evolved resistance to Bt cotton in Asia, where it remains a critical pest, and the benefits of using transgenic Bt crops have been lost. A complete annotated reference genome is needed to improve global Bt resistance management of the pink bollworm. We generated the first chromosome-level genome assembly for pink bollworm from a Bt-susceptible laboratory strain (APHIS-S) using PacBio continuous long reads for contig generation, Illumina Hi-C for scaffolding, and Illumina whole-genome re-sequencing for error correction. The pseudo-haploid assembly consists of 29 autosomes and the Z sex chromosome. The assembly exceeds the minimum Earth BioGenome Project quality standards, has a low error rate, is highly contiguous at both the contig and scaffold levels (L/N50 of 18/8.26 MB and 14/16.44 MB, respectively), and is complete, with 98.6% of lepidopteran single-copy orthologs represented without duplication. The genome was annotated with 50% repeat content and 14,107 protein-coding genes, further assigned to 41,666 functional annotations. This assembly represents the first publicly available complete annotated genome of pink bollworm and will serve as the foundation for advancing molecular genetics of this important pest species. [ABSTRACT FROM AUTHOR]

Pink bollworm, Pectinophora gossypiella (Saunders) originates from South Asia and has spread across major cotton-growing regions. The pest is considered to be the most destructive and of economic concern across the globe. In India, the pest has developed resistance to dual Bt toxins and its concealed feeding nature makes the target sites almost inaccessible for the insecticide. In view of this issue, there is need to identify a suitable alternative for its management. In this context, semiochemicals serve as one of the best eco-friendly options. These chemical substances or mixtures broadcast messages for the purpose of communication. Semiochemicals may be released from eggs, faecal pellets, tarsal segments, scales, anal tufts and/or any insect components that reduce the intra/interspecific competition for shared resources such as food, mating, oviposition site etc. Accurate identification of the semiochemical compounds and their proportion in natural blends that arouse a strong behavioural response in insects, requires a thorough knowledge. Therefore in the present study, we tried to explore the chemicals present in eggs, faecal pellets and whole-body wash extracts of mated female. Seven compounds were identified from a methanolic extract of faecal-pellet samples, namely hexadecanoic acid, 9,12-octadecadienoic acid, 9-octadecenoic acid and their methyl esters along with methyl stearate. However, only four methyl-esterified forms were found in common in eggs and female body wash extract. This clearly shows that the compounds remain constant and conserved for the species but the role of these compounds needs to be demonstrated. [ABSTRACT FROM AUTHOR]

FH-444 is a new Bt cotton variety which was released during the year 2020-21 by Cotton Research Station, Ayub Agricultural Research Institute, for irrigated areas of Punjab, Pakistan to maintain fiber quality and production through gradually replacement of existing cotton cultivars to avoid the yield losses caused by insect, pest and unexpected disease attacks. The FH-444 possesses drought tolerance and very good combination of traits to meet the requirements of the farmers, pickers, ginners, spinners and textile industry. The evaluation of this promising line was started during 2011-12 in different yield tests viz: preliminary & advance yield trials, Provincial Coordinated Cotton Trial (PCCT), National Coordinated Varietal Trial (NCVT), Distinctness, Uniformity and Stability (DUS) Trial, Agronomic trials, 1.25 Acre trials etc. In preliminary yield trials, FH-444 showed 45.96% increase in yield (3592 kg/ha) over standard variety FH-113 (2461 kg/ha) during 2011-12 while in advanced yield trials, FH-444 exhibited 23.61% increase in yield (3408 kg/ha) over standard variety FH-113 (2757 kg/ha) during 2013-14. It was also found that the effects of Cotton Leaf Curl Disease (CLCuD) were low (1.7 %) in FH-444 during growing season of 2014-15, while FH-142 showed increased incidence of attack (4.9%). FH- 444 demonstrated significant resistance with respect to thrips, whitefly, jassid and pink bollworm infestation. In present study it was found that the variety FH-444 possesses higher yield potential and will contribute to improve cotton yield and production under different stress conditions. [ABSTRACT FROM AUTHOR]

Cotton is white gold and contributes significantly to the economy of the countries. The process of evolution of resistance in various cotton insects directly affects the life of people. Among the cotton insect pests, pink bollworm (Pectinophora gossypiella) and army bollworm (Spodoptera litura) have turned out to be destructive. The development of seed using gene stacking approach has tremendously reduced the applications of agrochemicals making the technology greener for society. A gene cassette containing Cry11 and Cry1H genes was constructed. The cassette was cloned into the pCAMBIA2300 plant expression vector using the CAMV3-35S promoter. The construct was transformed into cotton line FBS-222 using the shoot apex-cut Agrobacterium-mediated transformation method. The expression of the Cry genes was 3-fold higher in transgenic than the non-transgenic cotton plants using qRT-PCR. Finally, the insect bioassay with transgenic cotton showed 90% mortality against pink bollworms and 80% against cotton army bollworms. The results demonstrate the development of seeds using the gene pyramiding approach is an effective strategy to control insect pest attacks. [ABSTRACT FROM AUTHOR]