Current status of phosphine resistance in Indian field populations of Tribolium castaneum and its influence on antioxidant enzyme activities.

Resistance to phosphine is widely reported in several stored product insect pests globally. However, knowledge of its prevalence and the association of antioxidant enzymes with phosphine resistance is limited. Herein, we assessed the levels of phosphine susceptibility and estimated the antioxidant enzyme activities viz., superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT) in selected Indian populations of red flour beetle Tribolium castaneum (Herbst). Dose-response probit assays revealed that the LC50 values ranged from 0.038 to 1.277 mg L-1 showing 2.11 to 70.94-fold resistance to phosphine compared to susceptible check. Activities of antioxidant enzymes varied significantly between the T. castaneum populations following phosphine exposure. The magnitude of SOD activity ranged from 8.77 to18.82 U mg-1 protein, while, the activities of POX and CAT varied between 52.42 and 408.32 and 61.11 to 247.49 µM H2O2 reduced min-1 mg-1 of protein, respectively. The correlation analysis revealed a significant positive association of SOD (r = 0.89) and POX (r = 0.98) with increased resistance ratio, while the CAT (r = - 0.98) is negatively linked with resistance to phosphine. A principal component analysis identified phosphine resistance was closely associated with POX and SOD activities but was unrelated to the CAT activity. Our results throw light on the varied association of antioxidant enzyme activities in response to phosphine fumigation in field populations of T. castaneum. Further studies on the biochemical and molecular basis of phosphine stress in insects may help to devise suitable strategies to safeguard storage commodities and ensure a sustainable environment.

Deciphering phenotyping, DNA barcoding, and RNA secondary structure predictions in eggplant wild relatives provide insights for their future breeding strategies.

Eggplant or aubergine (Solanum melongena L.) and its wild cousins, comprising 13 clades with 1500 species, have an unprecedented demand across the globe. Cultivated eggplant has a narrow molecular diversity that hinders eggplant breeding advancements. Wild eggplants need resurgent attention to broaden eggplant breeding resources. In this study, we emphasized phenotypic and genotypic discriminations among 13 eggplant species deploying chloroplast-plastid (Kim matK) and nuclear (ITS2) short gene sequences (400-800 bp) at DNA barcode region followed by ITS2 secondary structure predictions. The identification efficiency at the Kim matK region was higher (99-100%) than in the ITS2 region (80-90%). The eggplant species showed 13 unique secondary structures with a central ring with various helical orientations. Principal component analysis (PCoA) provides the descriptor-wise phenotypic clustering, which is essential for trait-specific breeding. Groups I and IV are categorized under scarlet complexes S. aethiopicum, S. trilobatum, and S. melongena (wild and cultivated). Group II represented the gboma clade (S. macrocarpon, S. wrightii, S. sisymbriifolium, and S. aculeatissimum), and group III includes S. mammosum, and S. torvum with unique fruit shape and size. The present study would be helpful in genetic discrimination, biodiversity conservation, and the safe utilization of wild eggplants.

Molecular Phylogeny, DNA Barcoding, and ITS2 Secondary Structure Predictions in the Medicinally Important Eryngium Genotypes of East Coast Region of India.

Commercial interest in the culinary herb, Eryngium foetidum L., has increased worldwide due to its typical pungency, similar to coriander or cilantro, with immense pharmaceutical components. The molecular delimitation and taxonomic classification of this lesser-known medicinal plant are restricted to conventional phenotyping and DNA-based marker evaluation, which hinders accurate identification, genetic conservation, and safe utilization. This study focused on species discrimination using DNA sequencing with chloroplast-plastid genes (matK, Kim matK, and rbcL) and the nuclear ITS2 gene in two Eryngium genotypes collected from the east coast region of India. The results revealed that matK discriminated between two genotypes, however, Kim matK, rbcL, and ITS2 identified these genotypes as E. foetidum. The ribosomal nuclear ITS2 region exhibited significant inter- and intra-specific divergence, depicted in the DNA barcodes and the secondary structures derived based on the minimum free energy. Although the efficiency of matK genes is better in species discrimination, ITS2 demonstrated polyphyletic phylogeny, and could be used as a reliable marker for genetic divergence studies understanding the mechanisms of RNA molecules. The results of this study provide insights into the scientific basis of species identification, genetic conservation, and safe utilization of this important medicinal plant species.

Indigenous plant protection practices of Tripura, India.

BACKGROUND: Traditional plant protection strategies have an integral part of food production system in North Eastern state Tripura, India, which has bestowed with rich heritage and biodiversity. However, there is no comprehensive report on the indigenous plant protection practices (IPPPs) specific to insect and vertebrate pest management, being followed by the inhabitants of the region for centuries. The present study was conducted to investigate, collect, and document the vulnerable IPPP practices followed by the native people from far flung locations of the Tripura. METHODS: The study aimed to document the IPPP following semi-structured questionnaires, participatory interaction, and direct observations with a total of 200 informants. We have calculated the relative frequencies of citation (RFC) for IPPP and estimated principal component analysis to link the status of IPPP with socio-demographic factors of the informants. The relationship between the field of IPPP used and different covariates (age, education, occupation, gender, location, and house type) was assessed using the Kruskal-Wallis test and Chi-square test. The relationship between adoption level and the respondents' characteristics was analyzed using count regression analysis. RESULTS: The study found that the status of the IPPP has increased for mitigating pest issues. A total of 39 indigenous practices were recorded specifically to pest management from the ethnic people of Tripura, India. People acquired pretty knowledge about IPPP, and these were inherited from ancestors. The respondents in the study developed notable innovations for the management of many pest issues using locally available resources that warrant cost-effective and eco-friendly. Seed drying before storage to protect grain commodities was the most cited IPPP with a frequency of citation 0.675. In the field of IPPP used, the people primarily practiced agriculture + horticulture + storage category. An important implication from the study is the identification of two IPPP strategies in this region for the first time. Furthermore, the recorded IPPP used field was significantly associated with age, education, occupation, gender, locality, and house type. Likewise, the respondents' socio-demographic variables were coupled considerably with the adoption of specific IPPP. CONCLUSION: The reported IPPP for alleviating pest problems reflects the wisdom and generosity of the ethnic growers of Tripura, India. The study suggests the IPPP has strong potential in an integrated pest management approach passed down from generation to generation. The vulnerable practices largely remained unexplored due to inadequate scientific scrutiny and authenticity, yet in danger of being lost if not documented systematically. This study provides the first step toward accessing the valuable technology of untapped Tripura in IPPP and could be viable in paving action paradigm for their preservation, diffusion, and application with advanced pest management options.