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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]

The cost-effectiveness of the hybrid design of microgrids for determining if a hybrid MG system is necessary is taken into consideration as the study focuses on improving power access in an optimal and economical manner. Both the cost of electricity (COE) and the loss of power supply probability (LPSP) of the hybrid MG design are optimized. The hybrid microgrid design including the photovoltaic (PV)-wind systems with battery storage and diesel generators are modeled and optimized for technical and economic feasibility using MATLAB. The energy management technique is applied between hybrid energy sources and loads. For this hybrid microgrid energy management system, an optimisation approach called spider monkey optimization (SMO) is employed. Using their distinct fission and fusion techniques, spider monkeys always engage in natural foraging behavior. Here, a variety of common constraints related to PV, wind, energy storage elements, inverters, and diesel generators with a variety of cost functions and dimensions are resolved by the proposed optimization method. The SMO optimization method is used to find a utilitarian optimal hybrid energy system configuration with a minimum COE, minimum LPSP, and leading renewable factor to meet the customer load throughout the entire time horizon. [ABSTRACT FROM AUTHOR]

The Bihar hairy caterpillar, Spilarctia obliqua, is a dreaded and sporadic pest on several cash crops in the Oriental region. The polyphagous feeding habit enables it to survive on a variety of crops. The group of hairy caterpillars of this study was found on young plants of the sweet basil. Young larvae feed gregariously on the under surface of the leaves later it feed solitary in nature. Damage symptoms, as skeletonization of the upper epidermis of the leaves, were observed. The identity of the pest species confirmed through morphological and molecular methods (No. MK491177). The phylogenetic analysis indicates the distribution of uniform populations of S. obliqua infesting soybean and sweet basil. The total life cycle was longest during winter (male, 68.67: female, 73.27 d) compared to Kharif season (male, 49.37; female, 53.74 d). The damage incidence ranged between 13.33–60% and 10–63.33% in 2018 and 2019, respectively. The natural enemy populations Glyptapanteles obliquae (11%) and Carcelia sp (17%) were recorded. This is the first report of S. obliqua on sweet basil, Ocimum basilicum, in India. [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]

Bacillus subtilis is a Gram-positive bacterium known for its antagonistic attributes, particularly through the production of various secondary metabolites, including lipopeptides. In this study, we investigated the antagonistic capabilities of B. subtilis strain NBAIRBSWG1 with a focus on assessing the efficacy of NBAIR-BSWG1 in combatting Sclerotium rolfsii. Our findings demonstrated substantial inhibitory effects, with 82.73% to 100% reduction in S. rolfsii growth when exposed to NBAIR-BSWG1 at concentrations ranging from 50 to 100 µL/mL in poison food technique. In dual culture assay, NBAIR-BSWG1 exhibited a significant 55.50% inhibition of S. rolfsii. Moreover, pot experiments revealed a promising 26% reduction in disease incidence. This study underscores the significant role of NBAIR-BSWG1 in controlling S. rolfsii, holding substantial potential for developing effective formulations aimed at mitigating the southern blight of tomatoes. [ABSTRACT FROM AUTHOR]

Bacillus turingiensis (Berliner) is a Gram positive, rod shaped and spore forming bacterium, which produces crystal proteins (proteinaceous inclusions), called δ-endotoxins, that have insecticidal action. The present investigation was carried out to isolate B. thuringiensis from soil, leaf, compost, leaf litter, diseased larvae and rhizosphere samples collected from the various locations in the states of Uttarakhand, Himachal Pradesh, Kerala, Karnataka and Maharashtra. A total of 300 samples were collected and isolation of the B. thuringiensis strains was carried out. The presence of crystalline inclusions in Bacilli like colonies was observed in 49 samples collected from the state of Uttarakhand, eight samples from Himachal Pradesh, six samples from Kerala, four samples from Karnataka and three samples from Maharashtra. Totally, 70 isolates showed milky white colonies with circular shape and colonies produced serrated margin similar to that of the reference strain HD1. Gram staining revealed that all the 70 isolates were rod-shaped, gram-positive bacteria, which were appeared to be blue or violet in colour under the Phase contrast microscope. Among the 70 isolates, 67 (97.74%) isolates showed bipyramidal type of crystal and the remaining three isolates such as, Bt-21, Bt-37 and Bt-278 showed square, elliptical and spherical crystal shape, respectively. The present study has established the diversity and richness of B. thuringiensis like isolates in soil and leaf samples collected from five selected states of India. [ABSTRACT FROM AUTHOR]

Abstract The broad mite, Polyphagotarsonemus latus (Tarsonemidae: Acari) is a highly polyphagous species that damage plant species spread across 57 different families. This pest has developed high levels of resistance to some commonly used acaricides. In the present investigation, we deciphered the genome information of P. latus by PacBio HiFi sequencing. P. latus is the third smallest arthropod genome sequenced so far with a size of 49.1 Mb. The entire genome was assembled into two contigs. A set of 9,286 protein-coding genes were annotated. Its compact genome size could be credited with multiple features such as very low repeat content (5.1%) due to the lack of proliferation of transposable elements, high gene density (189.1/Mb), more intronless genes (20.3%) and low microsatellite density (0.63%).

Codling moth is being reported in other countries of the world. It is a destructive and direct pest on apples and other fruit crops. The pathway for the occurrence of codling moth in the isolated belt of Baramulla is a cause of concern, and there is a need to contain this insect pest in other fruit-growing areas of Kashmir Valley. Here, we report a codling moth attacking apple and pear plants in the incursion belt.The fruit damage on apple in the belt was recorded more than 10% on delicious varieties. The codling moth was monitored and identified by using species-specific sex pheromone. The morphological and molecular tools were used to identify the codling moth. [ABSTRACT FROM AUTHOR]

Abstract Background Maize fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a highly migratory polyphagous insect pest that has posed itself as a very threatened insect invaded India since May 2018 and devastated the maize crop. This insect pest caused 62.5% damage on maize plants in Hassan district of Karnataka state, India. Surveys were undertaken in different parts of the country to assess the natural occurrences of all three categories of entomopathogens (bacteria, fungi, and viruses) associated with fall armyworm. Maximum occurrence of infection of entomopathogens (15.13%) was recorded from Chikkaballapura, Karnataka, followed by 12.23% from Hassan, Karnataka. Results Totally 13 isolates of S. frugiperda nucleopolyhedrovirus (SpfrNPV) were collected from 13 locations of the country. Electron microscopy studies clearly showed the tetrahedral shaped occlusion bodies of SpfrNPV with the size of 1.48–1.68 µm. The identity of highly virulent SpfrNPV NBAIR1 (Chikkaballapura isolate) was confirmed using conserved polyhedrin gene-specific primers and NCBI GenBank accession number was obtained (MT422725). Bioassay studies revealed that the SpfrNPV NBAIR1 Chikkaballapura isolate was highly virulent with the highest larval mortality (95.50%) and the lowest LC50 value of 2.11 × 103 OBs/ml. SpfrNPV is exclusively host specific and did not infect any other insect species other than S. frugiperda tested in this present study. Conclusions Among 13 isolates of SpfrNPV, SpfrNPV NBAIR1 Chikkaballapura isolate was highly virulent with respect to the larval mortality. Hence SpfrNPV NBAIR1 Chikkaballapura isolate is having a great potential to play in the management of maize fall armyworm S. frugiperda.