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1.
Bull Entomol Res ; 114(2): 293-301, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600043

RESUMO

One of the key reasons for the poor performance of natural enemies of honeydew-producing insect pests is mutualism between ants and some aphid species. The findings demonstrated that red wood ant, Formica rufa Linnaeus (Hymenoptera: Formicidae) had a deleterious impact on different biological parameters of the lady beetle, Hippodamia variegata Goeze (Coleoptera: Coccinellidae). H. variegata laid far fewer eggs in ant-tended aphid colonies, laying nearly 2.5 times more eggs in ant absence. Ants antennated and bit the lady beetle eggs, resulting in significantly low egg hatching of 66 per cent over 85 per cent in ant absent treatments. The presence of ants significantly reduced the development of all larval instars. The highest reduction was found in the fourth larval instar (31.33% reduction), and the lowest in the first larval instar (20% reduction). Later larval instars were more aggressively attacked by ants than earlier instars. The first and second larval instars stopped their feeding and movement in response to ant aggression. The third and fourth larval instars modified their mobility, resulting in increased ant aggression towards them. Adult lady beetles were shown to be more vulnerable to ant attacks than larvae. However, H. variegata adults demonstrated counterattacks in the form of diverse defensive reaction behaviours in response to F. rufa aggression.


Assuntos
Formigas , Besouros , Larva , Animais , Formigas/fisiologia , Besouros/fisiologia , Besouros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Afídeos/fisiologia , Agressão , Feminino , Simbiose , Oviposição , Comportamento Predatório
2.
Mol Biol Rep ; 50(5): 4155-4163, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36881341

RESUMO

BACKGROUND: Rice is a key food grain contributor to the global food grain basket and is considered the main food crop in India with a large number of varieties released every year. SSR markers have proven to be an excellent tool for studying genetic diversity. As a result, the present study was done to characterize and assess genetic diversity as well as population structural aspects. METHODS AND RESULTS: Fifty genotypes of rice were characterized using 40 SSR markers to assess the genetic diversity and genetic relationship. A total of 114 alleles were amplified with an average of 2.85 alleles per locus. The Polymorphism Information Content (PIC) values varied from 0.30 (RM162) to 0.58 (RM413) with an average of 0.44. Gene diversity was in the range of 0.35 (RM162) to 0.66 (RM413), with an average value of 0.52, while heterozygosity ranged from 0.18 (RM27) to 0.74 (RM55), with an average of 0.39. The population structure revealed a narrow genetic base with only three major subpopulations. Analysis of molecular variance revealed that 74% of the variation was attributed within individuals, 23% was among individuals, and 3% was among populations. Pairwise Fst value of population A & B is 0.024, population B & C is 0.120 and population A & C is 0.115. Dendrogram grouped the genotypes into three clusters with wide variation among the accessions. CONCLUSION: Genotyping combined with phylogeny and population structure analysis proved to be a powerful method for characterizing germplasm in this study. There is significant gene flow within populations, as well as the presence of different combinations of alleles, and that allelic exchange rates within the populations are higher than among the populations. Assessing the genetic diversity among individual genotypes within populations is quite useful in selecting candidate parents for future breeding programs to improve the target traits in rice for the Himalayan region.


Assuntos
Oryza , Humanos , Oryza/genética , Variação Genética/genética , Melhoramento Vegetal , Fenótipo , Polimorfismo Genético , Genótipo , Filogenia , Alelos , Repetições de Microssatélites/genética
3.
Sci Rep ; 12(1): 20392, 2022 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-36437280

RESUMO

Chili (Capsicum annuum L.) and brinjal (Solanum melongena L.) are the most widely grown solanaceous crops in the world. However, their production has reduced over several years due to the attack of various fungal and bacterial pathogens and various abiotic factors. Still, the major constrain in their production are pathogens with fungal etiology, especially the fungal wilt of solanaceous crops. Fusarium oxysporum and Fusarium solani have been previously identified as the pathogens causing wilt disease in chili and brinjal. Recently, a new fungal pathogen F. equiseti has been reported as the causal agent of wilt disease infecting chili. The current study focused on identifying fungal pathogens associated with the wilted plants of chili and brinjal, collected from different parts of the Himalayan region of Kashmir valley, through morpho-cultural and molecular characterization. DNA extraction, PCR amplification, and sequencing were performed on various isolates. DNA barcoding using the internal transcribed spacer region (ITS) was used to identify the pathogen followed by the pathogenicity test. Further confirmation of the pathogen was done by sequencing of transcription elongation factor (TEF) and Calmodulin (CAL2). In current study Fusarium chlamydosporum has been reported as the wilt causing pathogen of chili and brinjal for the first time in Kashmir Himalayas.


Assuntos
Capsicum , Solanum melongena , Solanum melongena/microbiologia , Verduras , Produtos Agrícolas
4.
Mol Biol Rep ; 49(7): 7205-7217, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35729477

RESUMO

BACKGROUND: Kala zeera [Bunium persicum (Boiss.) Fedtsch] is one of the important spice crops of North Western Himalayas with lot of medicinal and culinary values. In spite of having great importance, this crop is under the threat of extinction due to loss of habitat and lack of awareness. The limited availability of the seeds has ultimately increased the economic value of this spice. The upmarket of Kala zeera leads to its adulteration with other black seeds and cumin seeds. The present investigation was undertaken to evaluate polyphenolics and antioxidant properties of Kala zeera genotypes collected from North Western Himalayas and to develop DNA barcodes that can ensure their purity and can also guide in conservation of selected Kala zeera germplasm lines. METHODS AND RESULTS: Various locations of North Western Himalayas were explored for collecting 31 diverse germplasm lines of Kala zeera. The collected germplasm was maintained at our experimental stations during 2019-2020 and 2020-2021. These genotypes were evaluated for different seed traits and the methanolic extract from Kala zeera seeds was examined for total phenolic content, total flavonoid content, antioxidant activities by DPPH and FRAP. The results revealed significant variation in seed traits, polyphenolic content and antioxidant properties. 100 seed weight ranged from 0.05 to 0.35 g, TPC ranged from 7.5 to 22.56 mg/g, TFC ranged from 0.58 to 4.15 mg/g, antioxidant properties DPPH ranged from 168 to 624.4 µg/ml and FRAP ranged from 0.72 to 6.91 mg/g. Further, three different barcodes (ITS, rbcL and psbA-trnH) were used to reveal the authenticity of selected Kala zeera. MEGA 5 software was used for clustering and the barcodes did clustering based on geographical distribution of Kala zeera germplasm. CONCLUSION: Based on molecular barcoding, best barcode combination was identified that may discriminate the Kala zeera germplasm vis-a-vis can authenticate their purity. Moreover, the identified DNA barcodes will have significant role in studying the evolutionary biology of Bunium species and will be important for designing a strategy to conserve the selected Kala zeera germplasm lines. The identified genotypes with high phenolic content and antioxidant activity can further be utilized in Kala zeera breeding programmes.


Assuntos
Apiaceae , Código de Barras de DNA Taxonômico , Antioxidantes , Apiaceae/genética , Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/genética , Melhoramento Vegetal , Sementes/genética
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