02409nas a2200337 4500008004100000022001400041245011600055210006900171260009200240300001200332490000700344520123200351653002701583653002301610653001401633653001601647653002501663653001101688653002701699653001301726100002801739700002201767700002101789700002001810700002401830700002301854700002201877700002001899700002601919856012601945 2008 eng d a0958-315700aComparison of Metarhizium isolates for biocontrol of helicoverpa armigera (Lepidoptera : Noctuidae) in chickpea0 aComparison of Metarhizium isolates for biocontrol of helicoverpa a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcFEB a809-8280 v183 a

Metarhizium isolates from soil (53) and insect hosts (10) were evaluated for extracellular production of cuticle degrading enzyme (CDE) activities such as chitinase, chitin deacetylase (CDA), chitosanase, protease and lipase. Regression analysis demonstrated the relation of CDE activities with Helicoverpa armigera mortality. On basis of this relation, ten isolates were selected for further evaluation. Subsequently, based on LT(50) of the 10 isolates towards H. armigera, five isolates were selected. Out of these five isolates, three were selected on the basis of higher conidia production (60-75 g/kg rice), faster sedimentation time (ST(50)) (2.3-2.65 h in 0.1% (w/v) Tween 80) and lower LC(50) (1.4- 5.7 x 10(3) conidia/mL) against H. armigera. Finally, three Metarhizium isolates were selected for the molecular fingerprinting using ITS sequencing and RAPD patterning. All three isolates, M34412, M34311 and M81123, showed comparable RAPD patterns with a 935G primer. These were further evaluated for their field performance against H. armigera in a chickpea crop. The percent efficacies with the three Metarhizium isolates were from 65 to 72%, which was comparable to the chemical insecticide, endosulfan (74%).

10aappressorium formation10achitin deacetylase10achitinase10achitosanase10aHelicoverpa armigera10aLipase10aMetarhizium anisopliae10aProtease1 aKulkarni, Shuklangi, A.1 aGhormade, Vandana1 aKulkarni, Girish1 aKapoor, Manisha1 aChavan, Santosh, B.1 aRajendran, Armugam1 aPatil, Sanjay, K.1 aShouche, Yogesh1 aDeshpande, Mukund, V. uhttp://library.ncl.res.in/content/comparison-metarhizium-isolates-biocontrol-helicoverpa-armigera-lepidoptera-noctuidae-002913nas a2200337 4500008004100000022001400041245014400055210006900199260009200268300001200360490000700372520169100379653002702070653002302097653001402120653002502134653002702159653001102186653002702197653001302224100002302237700002802260700002202288700002402310700002102334700002402355700002102379700002002400700002602420856012902446 2008 eng d a0958-315700aEffect of repeated in vitro sub-culturing on the virulence of metarhizium anisopliae against helicoverpa armigera (Lepidoptera : Noctuidae)0 aEffect of repeated in vitro subculturing on the virulence of met a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcMAY a337-3550 v183 a

The effect of repeated conidial sub-culturing of Metarhizium anisopliae on its virulence against Helicoverpa armigera (Hbner) was studied. The LT(50) observed against third instar larvae of H. armigera for the first sub-culture was 3.4 days; it increased to 4.5 and 5.6 days for the 20th and the 40th sub-cultures, respectively. The LT50 values after passage of the 40th sub-culture on H. armigera decreased to 4.4 and 3.7 days for the 40th (first in vivo) and the 40th (fifth in vivo) passages, respectively. Similarly, the LC(50) of M. anisopliae towards third instar larvae of H. armigera increased from the first sub-culture (0.17x10(4)) to (3.0x10(4)) for the 40th conidial transfers on potato dextrose agar and again decreased to 0.74x10(4) and 0.23x10(4) in the 40th (first in vivo) and the 40th (fifth in vivo) passage, respectively. Similar trends for LC(50) and LT(50) values were seen when sugarcane woolly aphid, Ceratovacuna lanigera Zehntner was used as a host. Significant variation in appressorium formation and cuticle-degrading enzyme production such as chitinase, chitin deacetylase, chitosanase and protease during subsequent sub-culturing and passage through H. armigera was observed. Though there was no effect on internal transcribed spacer (ITS) sequence pattern, interestingly, in randomly amplified polymorphic DNA (RAPD), significant differences in the band intensities and in the banding pattern for different sub-cultures of M. anisopliae were observed. As stable virulence towards the insect pest is desirable for commercialisation of a mycoinsecticide, such changes in virulence due to repeated in vitro transfer need to be monitored and minimised.

10aappressorium formation10achitin deacetylase10achitinase10aHelicoverpa armigera10ain vitro sub-culturing10aLipase10aMetarhizium anisopliae10aProtease1 aNahar, Pallavi, B.1 aKulkarni, Shuklangi, A.1 aKulye, Mahesh, S.1 aChavan, Santosh, B.1 aKulkarni, Girish1 aRajendran, Armugham1 aYadav, Priya, D.1 aShouche, Yogesh1 aDeshpande, Mukund, V. uhttp://library.ncl.res.in/content/effect-repeated-vitro-sub-culturing-virulence-metarhizium-anisopliae-against-helicoverpa-002401nas a2200265 4500008004100000022001400041245011800055210006900173260000800242300001200250490000700262520150500269653002001774653001501794653001401809653001901823653002501842653002901867653002601896653001601922653002701938100002101965700002601986856012302012 2019 eng d a0233-111X00aPuzzle of highly virulent Metarhizium anisopliae strains from Annona squamosa fields against Helicoverpa armigera0 aPuzzle of highly virulent Metarhizium anisopliae strains from An cAPR a392-4010 v593 a

In our search for indigenous virulent strains of the entomopathogenic fungi, we observed that Metarhizium isolates from soils associated with Annona squamosa (custard apple) have higher virulence (>90% mortality of Helicoverpa armigera larvae at 1/10(th) spore concentration) than strains isolated from Solanum lycopersicum (tomato) fields. Proteomic analysis revealed two insecticidal cyclopeptides of A. squamosa origin in the M. anisopliae strains that led to higher virulence against H. armigera. Transcriptomic and genomic data indicated that M. anisopliae strains and A. squamosa had more than 20 genes in common, including those for cyclic hexapeptide synthase, non-ribosomal peptide synthetase, and plant cyclotide genes, which are involved in the biosynthesis of insecticidal cyclopeptides. These genes were absent in M. anisopliae strains isolated from the S. lycopersicum fields. Further, these strains can establish an endophytic relationship with A. squamosa suggesting that these rhizospheric strains originally could be endophytes, which were eventually released into the soil. Further, Metarhizium strains associated with Capsicum annuum (chili), Azadirachta indica (neem), and Carica papaya (papaya) - plants with insecticidal properties - also had higher virulence against H. armigera. Thus exploration of rhizospheres of plants producing insecticidal metabolites to isolate entomopathogenic fungi, per se, could be a viable strategy in agricultural for crop protection.

10aAnnona squamosa10aBiocontrol10aendophyte10aentomopathogen10aHelicoverpa armigera10ahorizontal gene transfer10ainsecticidal peptides10aMetarhizium10anatural transformation1 aPathan, Ejaj, K.1 aDeshpande, Mukund, V. uhttp://library.ncl.res.in/content/puzzle-highly-virulent-metarhizium-anisopliae-strains-annona-squamosa-fields-against