Functional Analaysis Of Entomopathogenic Fungi And Novel Protein Elicitor (PeLL1) Extracted From Lecanicillium Lecanii Against Whitefly,Bemisia Tabaci In Cotton

1.Entomopathogenic fungi have been successfully developed as a control agent for several insects in the world.Lecanicillium lecanii plays a vital role in the natural mortality of whitefly populations.The current study was performed to investigate three strains of Lecanicillium lecanii fungi previously known us Verticillium lecanii V3,V4,and V5 against Bemisia tabaci under laboratory conditions.The studies tested different applications i.e.,conidia,filtrate,and binary combinations using a leaf deep method.In conidial applications,three different concentrations(1×10⁵,1×10⁶and 1×10⁷conidia ml^-1)of each fungal strain were used.In filtrate applications,2 ml fungal filtrate of each strain was used,while in binary combination bioassays(1ml conidia+1ml filtrate)were estimated.Bemisia tabaci mortality rate was recorded after 3,5,6 and 7 days application.According to the results,maximum pathogenicity test against whitefly was observed at 7th day of all treatments.In the conidial concentration application,V3showed maximum mortality(90.6%)against Bemisia tabaci,and V4 strain showed the lowest mortality(80.4%)at the highest concentration(1×10⁷conidia ml^-1)at 7 days application.Infiltrate application,Maximum mortality(93%)was recorded in V3 strain,while binary combinations of(V3×V3)strains showed the highest mortality rate(84.6%)against B.tabaci.Our finding showed that the filtrate application V3 the most effective control against whitefly.The study will help to understand strategies for alternative options to insecticidal control of these pests.2.Whitefly,Bemisia tabaci is the most destructive cotton pest in all over the world.Control of whitefly by entomopathogenic fungi is an alternative option in sustainable agriculture.The studies were performed to isolate partially purified protein from Lecanicillium lecanii(L.lecanii)and analyzed its activity on the development and fecundity of whitefly.Three different concentrations of a partially purified proteins 22.31?g/ml,11.15?g/ml,and 7.43?g/ml were used on the 3-leaf stage on potted cotton plants and newly emerged(0–6 h old)adult whiteflies were exposed to these treated leaves.Control plants were sprayed with buffer(50 m M Tris-HCl,p H 8.0).Results of bioassays showed that the application of purified protein exhibited pronounced and significant(p<0.05)sub-lethal effects on whitefly.The fecundity rate was reduced and the nymphal development time was prolonged by different concentrations of partially purified protein from L.lecanii.Our finding suggests the potential application of partially purified protein derived from L.lecanii in future bio intensive insect pest management strategies such as Bemisia tabaci.3.This study was aimed the characterization of the novel protein elicitor isolated from entomopathogenic fungi Lecanicillium lecanii(V3)strain and check its activity against Whitefly,Bemisia tabaci in cotton.The sequence of purified elicitor protein showed 100%similarity with hypothetical protein LEL?00878[Cordyceps confragosa RCEF 1005],(Gen Bank Accession No.OAA81333.1).This novel protein elicitor has 253 amino acid residues and 762bp with molecular mas of29 k Da.The protein recombinant was expressed in Escherichia coli using p ET?28a(+)plasmid.Effects of purified novel protein elicitor on Bemisia tabaci were applied three different concentrations of protein(i.e.,58.32,41.22,35.41?g/ml)on cotton plants along with buffer(50 m M Tris-HCl,p H 8.0)as control,treated and untreated plants were exposed newly molted adult B.tabaci.Bioassay results exhibited a significant effect(P?0.001)of all the concentrations of protein on the fecundity rate of B.tabaci.In addition,the RT?q PCR gene expression analyses found a significant up?regulation of most of the key genes associated to salicylic acid(SA)and jasmonic acid(JA)linked plant defense pathways in elicitor protein treated plants.Our results suggested that the potential application of novel protein elicitor derived from Lecanicillium lecanii in future bio-intensive controlling approaches against sap-sucking insects such as whitefly,Bemisia tabaci.