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Pomegranate (Punica granatumL.) cultivation was first practiced in eastern nations like India and the Mediterranean regions. India stands first in pomegranate production and cultivated area in the world. During the year 2021, powdery mildew symptoms were observed on pomegranate plants of the cultivar G-37 and P-23 at the research farm (Dhanda) of ICAR-IARI Regional Station, Amartara Cottage, Shimla, 171,004 Himachal Pradesh, India. The research farm comes under the southwestern ranges of the Himalayas. The disease incidence was recorded to be 40% in both cultivars. The premature leaves and buds were covered in the dense, white mycelium and conidial mass patches that were powdery in appearance. Microscopic examination revealed the presence of enormous ellipsoid conidium structures associated with the diseased specimen. The conidiophores foot-cells were slightly tapered to straight measuring 70–190 × 4–7 μm. Conidia was hyaline, 37–27 × 14–11 μm (average 31.96 × 12.93 μm), however, chasmothecia could not be observed in the specimen. The molecular identification based on internal transcribed spacer region primers disclosed the fungus identity as Erysiphe punicae. The pathogenicity test was subsequently performed to prove the Koch postulates on the initially identified host cultivar P-23. To the best of our knowledge, this is the first report of powdery mildew of pomegranate caused by Erysiphe punicaein India.

During 2018 summer season (April–May), several young (1–3-year-old) arecanut seedlings exhibited yellowing, drying, drooping and wilting symptoms in farmer’s gardens located in Dakshina Kannada district of Karnataka, India. The longitudinal section of the infected seedlings showed extensive decaying of fibrous roots which extended up to the collar region and ultimately resulted in the death of young seedlings. A series of cultural, morphological, molecular characterization using multi-gene phylogeny and pathogenicity assays with Koch’s postulates confirmed the association of Fusarium falciforme(FSSC 3 + 4) as the causal organism of arecanut root decay disease. To the best of our knowledge, the present study confirms the first report of root decay disease caused by F. falciformein arecanut.

Background: Woolly apple aphid (Eriosoma lanigerumHausmann) (Homoptera: Aphididae) infests the aerial and edaphic portions of apple trees. It is responsible for the serious qualitative and quantitative reduction in apple fruits. This pest is mainly managed by chemical insecticides, so this present study was focused on the isolation of native entomopathogenic fungi (EPF), studying their growth characteristics and virulence against woolly apple aphids. Results: Clonostachys rogersoniana, as an EPF from an insect cadaver, was isolated and characterized, using morphological, microscopic, and molecular techniques. To the best of our knowledge, this is the first report of the occurrence of this fungus from India and it is named “C. rogersonianaisolate PUSACR01”. The radial growth and conidial yield of this isolate were excellent on PDAY among ten different culture media, whereas the relative growth rate and conidial germination were good on PDA and CA. The isolated fungus showed 85 and 86.67% mortality rates in adult females of the woolly apple aphid on day 11 at a concentration of 1.0 × 107and 1.0 × 108conidia ml−1, respectively. The LC50values determined by probit regression analysis for days 7, 9, and 11 were 1.12 × 107, 2.52 × 106,and 4.74 × 105conidia ml−1,respectively, while LT50for concentrations of 1.0 × 105, 1.0 × 106, 1.0 × 107, and 1.0 × 108conidia ml−1were 18.73, 9.39, 6.71, and 5.03 days, respectively. Conclusion: Based on the present study, C. rogersonianawould be considered a good biological control agent against the woolly apple aphid in apple orchards.

Cactodera estonicais a cyst forming plant parasitic nematode, recently reported from two important world biodiversity hotspots such as Nilgiris and Himalayan Biospheres of India. It poses a serious threat to the biodiversity of both the biospheres. Therefore, in the present study, efforts were made to evaluate the in-vitroefficacy of an entomopathogenic fungus Verticillium lecaniiisolate (ITCC 7084) against C. estonica. The effect of different treatments viz., T1-10%, T2-20%, and T3-30% cell suspension of 1.7 × 105CFUs of V. lecaniiisolate was observed against cysts and eggs of C. estonicaat 8, 24, 48, and 72 h after inoculation (HAI). The fungal isolate was found very effective and acted very fast against cysts and eggs of C. estonica. Within 24 h the growth of fungal mycelium was noticed on the cyst, however, at 48 and 72 HAI, significant differences were observed between the disintegration of the cysts and eggs inside the cyst in fungal treatments compared to untreated control. The percentages of leftover eggs and cysts were found inversely proportional to the concentration of V. lecaniiand the duration of exposure. The present study concluded that V. lecaniiisolate (ITCC 7084) is highly effective against C. estonicaand can be utilized for its management in the future. Further, the studies should also focus on identifying enzymes responsible for the disintegration of the cyst wall and eggshell; in addition to this, the field efficacy of the isolate should be tested before its inclusion in the integrated nematode management program.

Potato cyst nematodes, Globodera pallidaand G. rostochiensis, are economically important and difficult to manage pests of the potato crop. The cyst of both the species looks similar and it is difficult to differentiate once it turns brown upon maturity. Early detection of the PCN at the species level is crucial to avoid its further spread and for adopting the appropriate management strategies. Therefore, in the present study, highly specific and sensitive loop-mediated isothermal amplification (LAMP) assay was developed to amplify mitochondrial-Sequence Characterized Amplified Region (SCAR) sequence of potato cyst nematode, G. pallida. The LAMP assay was completed within a shorter incubation period of 60 min at 60 °C followed by the reaction termination at 80 °C for 5 min. The developed LAMP assay exhibited high specificity for G. pallidaand did not detect any other species including its sibling species, G. rostochiensis.In sensitivity tests, the assay detected G. pallidaat 1000 times less DNA concentration (10 fg/µl) as compared to conventional PCR (10 pg/µl). In addition to this, the developed LAMP assay was tested for the detection of G. pallidadirectly from the soil samples, and even a single cyst mixed with soil was successfully detected by the developed assay. Moreover, the utility of low-cost instruments like hot water bath was also demonstrated for the detection of G. pallidafrom the soil.The developed LAMP is a rapid, highly specific, sensitive, and cost-effective technique for the species-specific detection of G. pallida. The developed assay will facilitate the rapid detection of G. pallidaat quarantine stations as well as from the fields which will help to stop its further spread in new areas and also to devise effective management strategies for sustainable potato production.

Background: India is the world's leading producer of coconuts. Many biotic and abiotic constrains limit global palm yield and among the biotic factors, the coconut rhinoceros beetle, Oryctes rhinoceros(L.) (Coleoptera: Scarabaeidae) is the major problem in India. The adult beetle attacks the unopened leaves and inflorescences, resulting in a yield loss of more than 10%. O. rhinocerosgrubs and adults have different feeding habits as the adults feed on plant tissues, whereas the grubs primarily feed on rotting organic matter. Non-feeding stage, i.e. the larval stage, which is cryptic in nature and spends nearly 90–160 days in the breeding site, is amenable to any control measures so as to reduce the population of actual damaging adult stage. However, indiscriminate use of chemical insecticides has created a lot of environmental and regulatory issues, thus warranting an ecologically safe and environmental friendly alternative option. Hence, indigenous entomopathogenic nematode (EPN) strains, viz. Heterorhabditis indica(CPCRI-Hi1), Steinernema abbasi(CPCRI-Sa1), and S. carpocapsae(CPCRI-Sc1), virulence and reproductive capacity were evaluated against second instar larvae of O. rhinoceros. Results: Oryctes rhinoceroslarval susceptibility to EPN significantly varied with the treatment dose and period of exposure. The highest larval mortality was observed with S. carpocapsae(100%), and S. abbasi(92%) at 10 days post treatment, whereas H. indicastrain induced 72% mortality. At 72 h of incubation, the LC50values of Sc1, Sa1 and Hi1 strains were 1078, 1663 and 9780 IJs larva−1, respectively. With different concentration of EPN tested, the production of infective juveniles (IJs) inside the cadavers for Sc1, Sa1 and Hi1 varied between 3223–10,365; 4722–96,572 and 3483–85,453 larvae−1, respectively. Conclusion: Based on the virulence, reproductive capacity, searching ability and LC50values, it is suggested that strain Sc1 have great potential as a biocontrol agent for the Oryctesmanagement in coconut palms under humid tropical ecosystem. Present study found the effective native strain against O. rhinoceros, and its field efficacy should be tested further to include the EPNs in the integrated pest management program in coconut.

Root-knot nematode (RKN), Meloidogyne incognita, is one of the most lingering and difficult to manage pest of black pepper in India. The options for controlling RKN are becoming increasingly limited due to the potential risk involved in environmental and health hazards. Biological control using Pasteuriais one of the most effective and efficient ways of nematode management. Pasteuriaspp. are obligate parasites of plant-parasitic nematodes and completely inhibit their fecundity. There is also a tremendous opportunity for the discovery of native strains adapted to local environmental conditions and nematode species. Therefore, in the present study, efforts were made to isolate the native strain of Pasteuriafrom the fields of black pepper. Random sampling was done from black pepper-growing areas of Kerala and Karnataka states of India. Out of 39 samples, Pasteuriawas found in 8 samples from the fields of ICAR-IISR, Kozhikode, Kerala, India. The host range study revealed that the identified Pasteuriastrain was very specific to M. incognitaand completed its life cycle in RKN. Infected females laid no eggs or egg masses; thus, Pasteuriaprohibited the total fecundity of the nematodes. The Pasteuriastrain was named as IISR-MiP for it was found in the fields of ICAR-IISR and its specificity towards M. incognita. The average size of the identified Pasteuriastrain IISR-MiP endospore was 2.75 μm. Light as well as scanning electron micrographs revealed 3 types of endospore attachments viz., conventional, inverted, and sideways. Further, it was found that endospores attached to the nematode cuticle in the maximum number in a conventional type of attachment (87.62%), followed by inverted (6.55%) and sideways attachments (5.82%). The inverted and sideways attachments were unique to the biology of Meloidogyne-Pasteuriainteractions, indicating the presence of collagen-like fibres on the entire surface of Pasteuriaendospores. Pasteuriastrain IISR-MiP had the potential biocontrol capabilities and provided an opportunity for its evaluation against M. incognitaon black pepper under field conditions.