Occurrence of Metarhizium spp. isolated from forest samples in South India and their potential in biological control of banana stem weevil Odoiporus longicollis Oliver

Abstract Background Thirty-six entomopathogenic fungi (EPF) were isolated from soil and insect cadaver samples, collected from different forest types, viz., wet evergreen, moist deciduous, dry deciduous and scrub type in South India. Partial sequences of two parsimony informative genes ITS and RPB1 were determined under a phylogenetic approach for assessing the genetic diversity. Results Twenty-seven RPB1 gene sequences and 34 sequences of ITS1, 5.8S and ITS2 regions belonging to 36 EPF were analysed for identification and characterization. Four species of Metarhizium viz., M. anisopliae, M. roberstii, M. majus and M. guizhouense were differentiated. The isolates could be grouped into four main clades of 1–5. Most of the fungi appeared to be closely related to M. anisopliae. Based on the colony characters, colour, conidial size and shape, 27 isolates were morphologically identified as M. anisopliae. Seven strains were apparently related to M. robertsii, three isolates were similar to M. majus and the remaining one was identified as M. guizhouense. Morphological studies in congruence with phylogenetic analysis resolved the species diversity. Bioassay studies showed that M. quizhouense, M. majus and M. robertsii were effective against the banana stem weevil Odoiporus longicollis. Conclusions This is the first attempt to study the diversity and occurrence of Metarhizium species in forests of South India. Wet evergreen forest of Aralam in South India was rich in EPF diversity particularly for three species namely, M. quizhouense, M. robertsii and M. anisopliae.

Download Full-text

Genetic Diversity of Pinus tabulaeformis Carr. Populations in Different Forest Types

Chinese Journal of Appplied Environmental Biology ◽

10.3724/sp.j.1145.2013.00421 ◽

2013 ◽

Vol 19 (3) ◽

pp. 421-425

Author(s):

Ming LI ◽

Shuxiang WAN ◽

Baojia GAO

Keyword(s):

Genetic Diversity ◽

Pinus Tabulaeformis ◽

Forest Types

Download Full-text

Effect of Disturbance Regimes on Spatial Patterns of Tree Species in Three Sites in a Tropical Evergreen Forest in Vietnam

International Journal of Forestry Research ◽

10.1155/2016/4903749 ◽

2016 ◽

Vol 2016 ◽

pp. 1-16 ◽

Cited By ~ 1

Author(s):

Do Thi Ngoc Le ◽

Nguyen Van Thinh ◽

Nguyen The Dung ◽

Ralph Mitlöhner

Keyword(s):

Spatial Patterns ◽

Tree Species ◽

Interspecific Interactions ◽

Abundant Species ◽

Evergreen Forest ◽

Small Scale ◽

Forest Types ◽

Disturbance Regimes ◽

Tropical Evergreen Forest ◽

Disturbed Forest

The effects of disturbance regimes on the spatial patterns of the five most abundant species were investigated in three sites in a tropical forest at Xuan Nha Nature Reserve, Vietnam. Three permanent one-ha plots were established in undisturbed forest (UDF), lightly disturbed forest (LDF), and highly disturbed forest (HDF). All trees ≥5 cm DBH were measured in twenty-five 20 m × 20 m subplots. A total of 57 tree species belonging to 26 families were identified in the three forest types. The UDF had the highest basal area (30 m2 ha−1), followed by the LDF (17 m2 ha−1) and the HDF (13.0 m2 ha−1). The UDF also had the highest tree density (751 individuals ha−1) while the HDF held the lowest (478 individuals ha−1). Across all species, there were 417 “juveniles,” 267 “subadults,” and 67 “adults” in the UDF, while 274 “juveniles,” 230 “subadults,” and 36 “adults” were recorded in the LDF. 238 “juveniles,” 227 “subadults,” and 13 “adults” were obtained in the HDF. The univariate and bivariate data with pair- and mark-correlation functions of intra- and interspecific interactions of the five most abundant species changed in the three forest types. Most species indicated clumping or regular distributions at small scale, but a high ratio of negative interspecific small-scale associations was recorded in both the LDF and HDF sites. These were, however, rare in the UDF.

Download Full-text

A tale of two forests: ongoing aridification drives population decline and genetic diversity loss at continental scale in Afro-Macaronesian evergreen-forest archipelago endemics

Annals of Botany ◽

10.1093/aob/mcy107 ◽

2018 ◽

Vol 122 (6) ◽

pp. 1005-1017 ◽

Cited By ~ 4

Author(s):

Mario Mairal ◽

Juli Caujapé-Castells ◽

Loïc Pellissier ◽

Ruth Jaén-Molina ◽

Nadir Álvarez ◽

...

Keyword(s):

Genetic Diversity ◽

Population Decline ◽

Evergreen Forest ◽

Continental Scale ◽

Diversity Loss

Download Full-text

Genetic diversity assessment and gene expression analysis of prolonged shelf-life genes in Mangalore melon (Cucumis melo ssp. agrestis var. acidulus)

10.21203/rs.3.rs-183494/v1 ◽

2021 ◽

Author(s):

Raghavendra Gunnaiah ◽

Ratnakar M. Shet ◽

Ashwini Lamani ◽

Dattatraya H. Radhika ◽

Rudrappa C. Jagadeesha

Keyword(s):

Genetic Diversity ◽

Shelf Life ◽

Candidate Genes ◽

Cucumis Melo ◽

South India ◽

Ethylene Biosynthesis ◽

Inter Simple Sequence Repeat ◽

Issr Markers ◽

Tree Construction ◽

Diversity Assessment

Abstract Mangalore melon (Cucumis melo ssp. agrestis var. acidulus) is a non-dessert melon, extensively grown in the coastal districts of South India, but hardly known to the rest of the World. Immature or mature fruits of Mangalore melon are used in preparation of delicious dishes such as vegetable stew, chutneys and curries. They are appreciated for nutritional values, long shelf life and biotic stress resistance. Seventy-nine accessions of Mangalore melon were collected from five states of South India and their genetic diversity was assessed using inter simple sequence repeat (ISSR) markers. Putative candidate genes of extended shelf life in Mangalore melon were studied by quantitative reverse transcription polymerase chain reaction in comparison with cantaloupe (Cucumis melo L.). Shelf life varied from 65 days to 300 days at room temperature. Six ISSR primers amplified 142 fragments ranging from 80 bp to 2380 bp with an average of 23.66 bands per marker on a high-resolution capillary electrophoresis system. Neighbor joining phylogenetic tree construction from the ISSR allele similarity based genetic distance revealed two major clusters with 46 and 33 accessions in each cluster. Expression of fruit ripening related genes of ethylene biosynthesis (1-aminocyclopropane-1-carboxylate synthase, 1-aminocyclopropane-1-carboxylate oxidase) and cell wall metabolism (polygalacturonase, xyloglucan endotransglucosylase/hydrolase and expansin) in Mangalore melons was significantly lower than the cantaloupe melon at 180 days after harvest. Mangalore melon is a promising genetic resource for enhancing the shelf life of melons and the putative candidate genes are useful in enhancing shelf life of cantaloupe following validation and conformation.

Download Full-text

Assessment of Genetic Diversity of Rheum species (Endangered Medicinal Herb of Indian Himalayan Region) using Molecular Markers

Research Journal of Biotechnology ◽

10.25303/1611rjbt147154 ◽

2021 ◽

Vol 16 (11) ◽

pp. 147-154

Author(s):

Anjali Uniyal ◽

Akhilesh Kumar ◽

Sweta Upadhyay ◽

Vijay Kumar ◽

Sanjay Gupta

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Fragment Length Polymorphism ◽

Dna Polymorphisms ◽

Inter Simple Sequence Repeats ◽

Pharmaceutical Industries ◽

Endangered Medicinal Herb ◽

Identification And Characterization ◽

Simple Sequence

The Rheum species are important medicinal plants that are facing extinction due to their unplanned development and overexploitation by pharmaceutical industries. DNA polymorphisms are not prone to environmental modifications, thus they are widely used for the identification and characterization of plants. The use of different molecular markers has enabled the researchers for the valuation of genetic variability and diversity in its natural zone of distribution. The conventional approach may take several years to yield this information. For the estimation of molecular and genetic variations in geographical zone of distribution, various molecular markers technique are available like RAPD (Randomly Amplified Polymorphic DNA), RFLP (Restriction fragment length polymorphism), ISSR (Inter-Simple Sequence Repeats), SSR and AFLP. The uses of different molecular markers for the study of genetic diversity have been discussed in the review.

Download Full-text

Russian-olive (Elaeagnus angustifolia) genetic diversity in the western United States and implications for biological control

Invasive Plant Science and Management ◽

10.1017/inp.2019.16 ◽

2019 ◽

Vol 12 (02) ◽

pp. 89-96 ◽

Cited By ~ 2

Author(s):

John F. Gaskin ◽

Jose A. Andrés ◽

Steven M. Bogdanowicz ◽

Kimberly R. Guilbault ◽

Ruth A. Hufbauer ◽

...

Keyword(s):

United States ◽

Genetic Diversity ◽

Biological Control ◽

Biological Control Agent ◽

Isolation By Distance ◽

Western United States ◽

Elaeagnus Angustifolia ◽

Genetic Cluster ◽

Russian Olive ◽

Geographic Population

AbstractInvasions can be genetically diverse, and that diversity may have implications for invasion management in terms of resistance or tolerance to control methods. We analyzed the population genetics of Russian-olive (Elaeagnus angustifoliaL.), an ecologically important and common invasive tree found in many western U.S. riparian areas. We found three cpDNA haplotypes and, using 11 microsatellite loci, identified three genetic clusters in the 460 plants from 46 populations in the western United States. We found high levels of polymorphism in the microsatellites (5 to 15 alleles per locus; 106 alleles total). Our native-range sampling was limited, and we did not find a genetic match for the most common cpDNA invasive haplotype or a strong confirmation of origin for the most common microsatellite genetic cluster. We did not find geographic population structure (isolation by distance) across the U.S. invasion, but we did identify invasive populations that had the most diversity, and we suggest these as choices for initial biological control–release monitoring. Accessions from each genetic cluster, which coarsely represent the range of genetic diversity found in the invasion, are now included in potential classical biological control agent efficacy testing.

Download Full-text

DNA-Based Marker Systems to Determine Genetic Diversity of Weedy Species and Their Application to Biocontrol

Weed Science ◽

10.1017/s0043174500081546 ◽

1995 ◽

Vol 43 (3) ◽

pp. 504-513 ◽

Cited By ~ 54

Author(s):

Scott J. Nissen ◽

Robert A. Masters ◽

Donald J. Lee ◽

Martha L. Rowe

Keyword(s):

Genetic Diversity ◽

Biological Control ◽

Weed Control ◽

Random Amplified Polymorphic Dna ◽

Biological Weed Control ◽

Multiple Introductions ◽

Introduced Populations ◽

Length Polymorphisms ◽

Geographic Origins ◽

Weedy Species

DNA-based molecular markers may provide information about introduced weedy species that would be useful in biological weed control efforts. Chloroplast DNA restriction fragment length polymorphisms (cpDNA RFLP) and random amplified polymorphic DNA (RAPD) analysis are two DNA-based marker techniques that can provide estimates of genetic variation in native and introduced populations of weedy species. Profiles provided by these techniques could furnish the necessary information to determine the geographic origins of introduced species and provide evidence for multiple introductions. Although DNA-based markers would not necessarily identify the genetic basis for host-pest compatibility, they would enable identification of specific host genotypes. Current criteria for selecting a weedy species as a target for biological control are primarily political and economic. The importance of genetic diversity and population structure in determining the vulnerability of plant populations to insects or diseases has not been fully appreciated. Estimates of genetic diversity based on DNA marker analysis could be used as one criteria for determining which plants are targeted for biological control. The success of biological weed control efforts has been limited by the high levels of genetic diversity occurring in target weed specks and the lack of biocontrol agent and target weed compatibilities. DNA-based markers may be used to increase our understanding of these factors and contribute to the success of biological weed control by helping to target the most vulnerable species and provide more realistic expectations of the potential for success given available resources.

Download Full-text

Patterns and drivers of genetic diversity and structure in the biological control parasitoid Habrobracon hebetor in Niger

Bulletin of Entomological Research ◽

10.1017/s0007485319000142 ◽

2019 ◽

Vol 109 (6) ◽

pp. 794-811

Author(s):

M. Garba ◽

A. Loiseau ◽

C. Tatard ◽

L. Benoit ◽

N. Gauthier

Keyword(s):

Genetic Diversity ◽

Biological Control ◽

Mating System ◽

Cropping Systems ◽

Nonrandom Mating ◽

Habrobracon Hebetor ◽

Complementary Sex Determination ◽

Genetic Diversity And Structure ◽

Field Samples ◽

Grain Stores

AbstractWhen a promising natural enemy of a key pest exists locally, it is a common practice in biological control (BC) to rear and release it for supplementary control in the targeted agroecosystem even though significant knowledge gaps concerning pre/post release may still exist. Incorporating genetic information into BC research fills some of these gaps. Habrobracon hebetor, a parasitoid of many economically important moths that infest stored and field crops worldwide is commonly used, particularly against the millet head miner (MHM), a key pest of millet in Sahelian countries. To advance our knowledge on how H. hebetor that occurs naturally in open-field cropping systems and grain stores as well as being mass-produced and released for MHM control, performs in millet agroecosystems in Niger we evaluated its population genetics using two mitochondrial and 21 microsatellite markers. The field samples were genetically more diverse and displayed heterozygote excess. Very few field samples had faced significant recent demographic bottlenecks. The mating system (i.e. nonrandom mating with complementary sex determination) of this species may be the major driver of these findings rather than bottlenecks caused by the small number of individuals released and the scarcity of hosts during the longlasting dry season in Niger. H. hebetor population structure was represented by several small patches and genetically distinct individuals. Gene flow occurred at local and regional scales through human-mediated and natural short-distance dispersal. These findings highlight the importance of the mating system in the genetic diversity and structure of H. hebetor populations, and contribute to our understanding of its reported efficacy against MHM in pearl millet fields.

Download Full-text