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Pomegranate (Punica granatum L.) 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 punicae in India. [ABSTRACT FROM AUTHOR]

Potato cyst nematodes, Globodera pallida and 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. pallida and did not detect any other species including its sibling species, G. rostochiensis. In sensitivity tests, the assay detected G. pallida at 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. pallida directly 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. pallida from 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. pallida at 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. [ABSTRACT FROM AUTHOR]

Serpentine leaf miner, from the genus Liriomyza, is one of the most economically important pests responsible for severe yield reductions in numerous vegetables crops worldwide including potato. Potato plays a significant role in the Indian economy. Potato production is being affected by several existing and new biotic stresses; correct and timely identification of new stresses is the key for their effective management. The Nilgiri hills located in Southern India is one of the oldest potato-growing areas of the country and is a prime centre in south India for potato production and supply. During the summer and autumn seasons of the year 2020, a leaf miner outbreak was observed in the potato-growing areas of the Nilgiri hills of Southern India. Here, we surveyed the potato fields to determine the species, damage severity, distribution, and possible alternate weed hosts of leaf miner. Based on the morpho-molecular characterization of the adult fly, the pest was identified as Liriomyza huidobrensis. During the outbreak, the incidence of this pest was 90–100%, with a damage severity ranging from 20 to 100% on the potato crop. The larval population varied from 1.2 to 14.83 larvae leaflet−1. It was also observed that the damage incidence and severity of L. huidobrensis infestation was influenced by the crop age and foliar injury increased with the advancement of crop age. In addition to potato, L. huidobrensis incidence was also recorded on six cultivated crops such as carrot, beetroot, garlic, beans, double beans, and broccoli. The incidence of the pest was also noticed on one cover crop, lupine and seven weed species (Amaranthus spp., Bidens pilosa, Chenopodium spp., Solanum nigrum, Galinsoga parviflora, Hypochaeris glabra, and Sonchus oleraceus) commonly observed in the Nilgiri hills. Field experiments for the management of L. huidobrensis with two potato cultivars (Kufri Swarna and Kufri Sahyadri) were also conducted to have an immediate option against this pest. These studies recommend the application of abamectin for the management of L. huidobrensis. The polyphagous nature of the pest coupled with increasing trade, transport, and changing climatic scenario possesses the risk of its spread in new geographical areas along with the possibility to attain the status of a major pest of potato and other crops in near future. Additionally, the Nilgiri hills are identified as one of the world's biodiversity hotspots. Therefore in future, the studies should focus on the exploration and conservation of biological control agents and evaluation of safer chemical molecules to minimize the crop losses and to avert its further spread in new localities. [ABSTRACT FROM AUTHOR]

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. falciforme in arecanut. [ABSTRACT FROM AUTHOR]

Potato has been recognized as a crop of importance in developing countries for ensuring human nutrition and food security. The dwindling natural resources, low fertility of soils, the incidence of pests and diseases, climate change and lack of strategic planning pose major constraints for potato production in these countries. Crop models are efficient tools for assisting research and development efforts towards achieving maximum production potential in these areas as it predicts the phenology and yield of crop taking into consideration the factors affecting growth and development. A well-validated model can be used for quantification of adaptation domains, optimization and efficient utilization of resources, forecasting of pest and diseases, mitigating climate changes, yield gap analysis, a pre-harvest judgment of production and accordingly market surveillance and formulation of monitory policies. The multifaceted application of simulation models presents futuristic opportunities for developing decision supporting systems and agro-advisory services for scheduling best management practices for attaining sustained potato production. This review summarizes comprehensive information on the crop models being used along with their applications in the different aspects of potato production system towards a precision as well as smart agriculture. [ABSTRACT FROM AUTHOR]

Background: Woolly apple aphid (Eriosoma lanigerum Hausmann) (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. rogersoniana isolate 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 × 107 and 1.0 × 108 conidia ml−1, respectively. The LC50 values determined by probit regression analysis for days 7, 9, and 11 were 1.12 × 107, 2.52 × 106, and 4.74 × 105 conidia ml−1, respectively, while LT50 for concentrations of 1.0 × 105, 1.0 × 106, 1.0 × 107, and 1.0 × 108 conidia ml−1 were 18.73, 9.39, 6.71, and 5.03 days, respectively. Conclusion: Based on the present study, C. rogersoniana would be considered a good biological control agent against the woolly apple aphid in apple orchards. [ABSTRACT FROM AUTHOR]

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 Pasteuria is one of the most effective and efficient ways of nematode management. Pasteuria spp. 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 Pasteuria from 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, Pasteuria was found in 8 samples from the fields of ICAR-IISR, Kozhikode, Kerala, India. The host range study revealed that the identified Pasteuria strain was very specific to M. incognita and completed its life cycle in RKN. Infected females laid no eggs or egg masses; thus, Pasteuria prohibited the total fecundity of the nematodes. The Pasteuria strain 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 Pasteuria strain 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-Pasteuria interactions, indicating the presence of collagen-like fibres on the entire surface of Pasteuria endospores. Pasteuria strain IISR-MiP had the potential biocontrol capabilities and provided an opportunity for its evaluation against M. incognita on black pepper under field conditions. [ABSTRACT FROM AUTHOR]

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. rhinoceros grubs 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 rhinoceros larval 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. indica strain induced 72% mortality. At 72 h of incubation, the LC50 values 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 LC50 values, it is suggested that strain Sc1 have great potential as a biocontrol agent for the Oryctes management 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. [ABSTRACT FROM AUTHOR]