First report on identification of volatiles from egg and larval frass of Indian strain of the American bollworm Helicoverpa armigera (Hübner)
A total of seven volatiles have been identified from methanol extract of eggs and faecal pellets, out of which two volatiles were detected in egg samples. From faecal pellets, five volatiles were identified. Interestingly, methyl ester of octadecanoic acid and methyl ester of hexadecanoic acid were detected in both samples. Volatiles observed in common may be used as effective semiochemicals in the ethological pest management of Helicoverpa armigera.
Further readings: https://journals.co.za/doi/abs/10.4001/003.027.0403
Improved bioassay method for evaluation of oviposition deterrents against Helicoverpa armigera (Hübner)
Suitable improved bioassay method for evaluation of effect of oviposition deterrents against H. armigera was developed. The duration of the bioassay method was finalized according to the peak activity of adult moth in terms of mating and fecundity. This investigation presents a method, for finding promising oviposition deterrent compound which will be helpful for researchers to identify the most potent molecule/compounds against H. armigera.
Further readings: http://op.niscair.res.in/index.php/IJEB/article/view/38372
Field-evolved resistance of pink bollworm, Pectinophora gossypiella to Bt cotton in India
Pink bollworm (PBW) adaptation to Bt cotton expressing Cry1Ac and Cry1Ac + Cry2Ab was assessed in India during 2010–2017 in 38 districts of the 10 major cotton-growing states. PBW larval incidence on Bt cotton was nil in northern India, wherein the resistance ratios (RRs) to Cry1Ac were 26–262 and those to Cry2Ab were 1–108. In central and southern India, the annual average PBW larval recovery from Bt II cotton was high at 28.85–72.49% during 2014–2017. In central and southern India, the 50% lethal concentration (LC50) of Cry1Ac increased from a mean of 0.330 µg mL−1 (range 0.126–0.849 µg mL−1) in 2013 to a mean of 6.938 µg mL−1 (range 3.52 to 10.30 µg mL−1) in 2017 and the RR increased from a mean of 47.12 (range 18–121) in 2013 to a mean of 1387 (704–2060) in 2017, whereas the LC50 value for Cry2Ab increased from a mean of 0.014 µg mL−1 (range 0.004–0.094 µg mL−1) in 2013 to a mean of 12.51 µg mL−1 (range 3.92 to 28.10 µg mL−1) in 2017 and the RR increased from a mean of 5.4 (range 1–31) in 2013 to a mean of 4196 (1306–9366) in 2017.
Further readings: https://onlinelibrary.wiley.com/doi/10.1002/ps.5038
Oviposition deterrents from pink bollworm, Pectinophora gossypiella (Saunders) and their conserved nature for the species
Three fatty acids namely, oleic, linoleic and palmitic acids were identified from larval faecal pellets of pink bollworm. The oviposition deterrent effect of these identified fatty acids was confirmed through laboratory bioassays. These identified fatty acids and their respective methyl esters remain conserved for the species was confirmed in pink bollworm.
Further readings: http://www.jeb.co.in/journal_issues/202005_may20/paper_17.pdf;
Oviposition preference of pink bollworm, Pectinophora gossypiella (Saunders)
The effect of four cultivated species of cotton on the oviposition behaviour and/or preference of pink bollworm, Pectinophora gossypiella was studied under laboratory conditions. Relative blend of volatiles in cotton square has a direct influence on the egg-laying behaviour and/or preference of pink bollworm as confirmed through series of choice and no-choice experiments under laboratory conditions. American cotton is preferred over Desi cotton for egg laying. From the choice experiments it is evident that the order of preference of pink bollworm for oviposition is Gossypium hirsutum > G. barbadense > G. arboreum > G. herbaceum.
Further readings: https://brill.com/view/journals/ab/72/4/article-p353_5.xml
Mass production method for cotton pink bollworm, Pectinophora gossypiella
Cotton seed based artificial diet has been standardized for continuous rearing of pink bollworm Pectinophora gossypiella (Saunders). The ingredients of the diet are easily available and are cost effective. Basic ingredients of the diet are cotton seed flour (processed) and chick pea flour, Carbohydrate, Protein, Fat sources, multi vitamin, antimicrobial agents and agar as thickening agent are used as other ingredients.
Further readings: https://www.sciencedirect.com/science/article/pii/S209098961500051X
Incipient infestations and threat of pink bollworm Pectinophora gossypiella on cotton in north zone of India
During 2018–19 cotton season, BG II cotton was found infested with Pink Bollworm at one location in Haryana and two locations in Punjab near cotton ginning and oil extraction units. Cotton seeds are being procured from the central and south India by many units where PBW has already acquired resistance against BG II hybrids. Bio-ecological and resistance monitoring studies of larvae collected from the infested location revealed absence of larval diapauses in surviving population and resistance levels equivalent to central/south zone populations. The threat perception of pink bollworm in north zone on BG II cotton was reported.
Further readings: https://www.currentscience.ac.in/Volumes/118/09/1454.pdf
A simple and low-cost laboratory rearing technique for pink bollworm, Pectinophora gossypiella using detached green bolls of cotton
A simple and inexpensive method that uses freshly excised green bolls (~10 d old) of cotton (Gossypium hirsutum L.) is developed for laboratory rearing of pink bollworm, Pectinophora gossypiella (Saunders). The developing larvae can be removed at any stage of their development for morphometric studies, conducting bioassays, etc. The insect raised by this method retained its ability to infest field-grown cotton. We could successfully raise up to five generations of pink bollworm by this method with the input of one labourer. This method is easily applicable and less expensive, and it would be highly useful in understanding the impacts of climate change on P. gossypiella phenology mediated through alterations and or aberrations in the nutritional status of its host crop i.e. cotton.
Further readings: https://link.springer.com/article/10.1007/s12600-019-00779-2
Innovative on-plant bioassay method for selection of superior genotype/cultivar/event against pink bollworm in cotton
A simple, and reliable method of on-plant bioassay for screening of genotypes or transgenic events against cotton pink bollworm is developed. The method involved releasing neonate larvae of pink bollworm on approximately 12–15 days old undetached bolls of non-Bt and Bt (Bollgard I and Bollgard II) cotton plants and covering them with a kite paper bag to prevent larval escape. The tagged bolls were kept undisturbed for next 21 days. After completion of this period the observations on larval entry holes, locular damage, exit holes and per cent damaged bolls were recorded in each case. The experiments were repeated for two consecutive cotton cropping seasons of 2018–19 and 2019–20 on early (100 DAS) and late (150 DAS) formed bolls on cotton plants.
Further readings: https://link.springer.com/article/10.1007/s42690-021-00512-9
Degree-day based phenology model for predicting the developmental events of cotton pink bollworm Pectinophora gossypiella (Saunders) in field
Using geographically and temporally extensive data sets of moth trap catches and temperatures across the cotton-growing states of India, we predicted the phenology of cotton pink bollworm Pectinophora gossypiella (Saunders). Our approach was centered on growing degree days (GDD), a measure of thermal accumulation that provides a mechanistic link between climate change and species’ phenology. The phenology change was predicted by calculating the absolute error associated with DD and ordinal date, an alternative predictor of phenology, for peak moth abundance. Our results show that GDD outperformed the ordinal dates in predicting peak moth abundance in 6 out of 10 selected locations.
Further readings: https://www.nature.com/articles/s41598-020-80184-6
Estimation and validation of developmental thresholds and thermal requirements for cotton pink bollworm Pectinophora gossypiella
Threshold temperatures and thermal requirements for pink bollworm were estimated and validated. Developmental thresholds of 13.4 °C/35.5 °C and thermal requirements of 503.62 DD were estimated. Simulation of life table parameters provided reasonably closer estimates across the tested locations. The estimated thresholds precisely predicted the pink bollworm developmental events under field conditions.
Further readings: https://www.sciencedirect.com/science/article/pii/S0261219419303308
Wireless smart trap for automated pest monitoring
To circumvent the limitations of the conventional trapping system, a wireless smart trap is developed to target multi species lepidopterous pests of cotton. Individual pheromone septa targeting the Pectinophora gossypiella, [7,11-hexadecadienyl acetate]; Spodoptera litura [(Z,E)-9,11-Tetradecadienyl acetate]; Helicoverpa armigera [Z-9-Hexadecenal] and Earias vittella [(E, E) – 10, 12- hexadecadienyl] are housed in a modified delta trap.
Mitochondria COI-based genetic diversity of the cotton leafhopper Amrasca biguttula bigutula (Ishida) populations from India
Amrasca biguttula biguttula (Ishida), the cotton leafhopper, is a polyphagous insect pest of Asia and Southeast Asian countries. We sequenced a mitochondrial COI gene fragment from 67 individuals of cotton leafhopper collected from 7 major cotton growing states of North, Central, and South India. Genetic divergence analysis of leaf hopper population across India confirmed the presence of single species. Thirty haplotypes, in total, were determined across different regions of India. While population from North India was dominated by single haplotype, the south and central Indian populations show dispersion of different haplotypes across the region.
Potential risk of establishment and survival of cotton aphid Aphis gossypii in India based on simulation of temperature-dependent phenology model
Investigated the effects of temperature on the biological parameters of A. gossypii by fitting different non-linear models to the data obtained from constant temperature experiments carried out between 12 and 32 ºC. The pest risk in different geographical areas was simulated using GIS tools and represented by two spatial indices viz. establishment risk index (ERI) and generation index (GI). The development rate as a function of temperature increased linearly until approximately 27 ºC, after which it became non-linear.
Further readings: https://www.tandfonline.com/doi/full/10.1080/09670874.2019.1649739
Diversity of thrips in cotton ecosystem
Seven species of thrips have been recorded infesting on cotton from South India. Scirtothrips dorsalis Hood, Thrips palmi Karny, and Thrips tabaci Lindeman were recorded from leaves and Thrips florum (Schmutz), Thrips hawaiiensis (Morgan), Frankliniella schultzei (Trybom) and Thrips parvispinus (Karny) were recorded from flowers of cotton plants. The most dominant species of thrips that are infesting cotton have been identified as Scirtothrips dorsalis, Thrips tabaci, and Thrips palmi from various cotton-growing zones of India.
Further readings: https://www.currentscience.ac.in/Volumes/122/02/0211.pdf
Mitochondrial COI based genetic diversity and phylogeographic structure of whitefly Bemisia tabaci (Gennadius) on cotton in India.
Population genetics of the cotton whitefly across all three cotton-growing zones in India investigated. Findings revealed that the Bemisia tabaci species can be classified into two primary genetic groups, known as Asia 1 and Asia II1. Our results showed that the Asia 1 group was predominantly present in the south-central zone, whereas the Asia II1 group was the dominant one in the northern zone. Furthermore, we established a standardized DNA extraction protocol from a single whitefly to ensure the accuracy of our genetic analysis.
Further readings: https://link.springer.com/article/10.1007/s42690-020-00354-x
CICR Whitefly Adult Suction Trap
The trap is power operated, shoulder mounted, portable, adjustable and sucks whitefly adults available on the underside of the cotton leaves. Trap helps in reduction of whitefly population ranging from 40-52% depending upon the pest population. The Trap should be used when pest incidence is high especially during two peak period of activity i.e. first flush (30 SMW) as well as during the later flush (40 SMW), in cotton ecosystem under North Indian condition. The traps can be operated when the weather is clear and there is no morning humidity and plants are dry.
Widespread infestation of the exotic mealybug species, Phenacoccus solenopsis (Tinsley), on cotton in India
Solenopsis mealybug, Phenacoccus solenopsis (Tinsley), which was hitherto not reported to occur in India was found to infest cotton plants in all nine cotton growing states of the country. P. solenopsis was predominant mealybug species, comprising 95% of the samples examined while pink hibiscus mealybug, Maconellicoccus hirsutus (Green) was 5%.
Further readings: https://www.cambridge.org/core/journals/bulletin-of-entomological-research/article/abs/widespread-infestation-of-the-exotic-mealybug-species-phenacoccus-solenopsis-tinsley-hemiptera-pseudococcidae-on-cotton-in-india/3C6D3D89CB2C21EC196A29FCB24A1C85
Tea Mosquito Bug
In cotton, Helopeltis theivora and Helopeltis antonii were the two species of tea mosquito bug recorded in Coimbatore, Tamil Nadu. The population dynamics of tea mosquito bug (TMB) showed that the incidence beginning in September and reached a peak during December. Temperature, sunshine hours and solar radiation are negatively correlated with the incidence of TMB, while relative humidity, rainfall and rainy days all showed positive correlations. Damage potential and yield loss caused by the tea mosquito bug on cotton revealed shoot damage ranges from 62-93% and grade index ranges from 1.56 to 3.26 while, boll damage ranges from 45 to 54% with grading of 1.6 to 2.06. One insect / plant can reduce yield by 10% compared to control. Maximum of 52% yield drop was recorded when 5 insects/plant are present compared to control.
BIOLOGICAL CONTROL AGENTS
INSECT PATHOGENS OF COTTON INSECT PESTS
Pathogenicity of entomopathogenic fungi
Based on pathogenicity of fourteen entomopathogenic fungi against Helicoverpa armigera larvae , Beauveria bassiana Bb-4 was identified as promising isolate. It could enter the cuticle and cause mortality within three days. Sporulation of fungus was observed on the larva.
Five entomopathogenic fungi viz., Beauveria bassiana CICR-Ps-Bb-1 (OK189586.1) from Phenacoccus solenopsis, Fusarium oxysporum CICR-Sf-Fo from Fall Army Worm, Spodoptera frugiperda (OK235489.1), Purpureocillium lilacinum CICR-S-Pl-1 from soil (OK189590.1), Aspergillus fischeri CICR-Ps-Af-1 from Phenacoccus solenopsis (OK235488.1) and Fusarium sp CICR-Ht-1 from Helopeltis theivora (OK235489.1) were submitted to GenBank.
Insecticide Resistance Management: Dissemination of Pink Bollworm Management Strategies
Since the last 6-7 years pink bollworm has become a serious menace on Bt cotton in India, causing widespread damage and significant yield losses to the tune of 20-30%. Keeping in view of the significant PBW infestation across all the cotton growing states, the project was approved during 2018-19 and since then continuing with the major objective to disseminate Pink Bollworm Management Strategies in Bt cotton. Department of Agriculture & Farmers Welfare (Crops & PHMF Division), Ministry of Agriculture and Farmers Welfare, Govt. of India is funding agency. During 2022-23, the project is being implemented by ICAR-CICR in 125 villages in 41 districts of 11 cotton growing states in collaboration with 13 State Agricultural Universities. Existing ICAR-CICR & 10 SAUs conducting demonstrations in 105 villages of 21 districts on area of 1050 acres. From the current year (2022-23), 20 KVKs (affiliated to SAUs & NGO) under 6 ATARIs (ATARI, Ludhiana, Jodhpur, Pune, Hyderabad, West Bengal, Bengaluru) are participating and conducting demonstrations in 20 villages of 20 districts on 500 acres area.
Innovative extension project “Crop Pest Surveillance and Advisory Project (CROPSAP) in Maharashtra
The project is an initiative of the Department of Agriculture, Government of Maharashtra to assist the farming community through Information & Communication Technology (ICT); is being implemented in collaboration with State Agricultural Universities viz, PDKV, Akola, VNMKV Parbhani, BSKKV Dapaoli, MPKV Rahuri; ICAR’s institutes namely ICAR-NCIPM New Delhi, ICAR-CICR, Nagpur, ICAR-CRIDA Hyderabad, ICAR-CRRI, Cuttack, NIPHM, Hyderabad etc. The project was conceived to develop a scientific approach to pest surveillance and monitoring of pests infesting Cotton, Soybean, Pigeonpea, Gram, Rice, Maize Sugarcane, etc on an area more than 100 lakhs hectares.
Further readings: https://cropsap.maharashtra.gov.in/dept/