000			04062nam a22002297a 4500
003			OSt
005			20250306134002.0
008			250306b ||||| |||| 00| 0 eng d
040			_cCPGS
100			_aRaj, Ritika _910304
245			_aEfficacy of fungal endophytes of tea ecosystem for the management of blister blight / _cRitika Raj.
260			_aUmiam : _bCPGSAS, CAU(Imphal), _cSeptember 2024.
300			_a94p.
440			_a[Plant Pathology, School of Crop Protection] _99105
504			_aIncludes bibliographical references.
520			_aIndia, a global tea titan contributing a quarter (23%) of the world's tea harvest, with Assam alone supplying more than half (52%), faces a formidable threat in blister blight, a devastating disease caused by the insidious fungus Exobasidium vexans. This scourge inflicts a staggering 40% loss in tea production. To shield this economic mainstay, a comprehensive investigation was undertaken in India's northeastern regions to devise an integrated strategy to combat this affliction. This study delved into the potential of endophytic fungi, microbial inhabitants of plant tissues, as a biological shield. In the present study 46 fungal endophytes were isolated from the stem, leaf and roots of tea of 9 gardens of 3 north eastern states of India and were characterized. During the study, it was found that roots harbored Beauveria bassiana, Verticillium lecanii, two species of Trichoderma and diversed Fusarium spp, the stem was a domain for Metarhizium robertsii, Colletotrichum spp, and three species of Trichoderma. Out of entire isolates, 30 isolates with vigorous growth were meticulously characterized and tested for their in-vitro efficacy against the E. vexans causing blister blight of tea. Results showed, Trichoderma harzianum (A2S3) as the most effective antagonist, exhibiting 74.4% mycelial inhibition against E. vexans. Its mode of action was found to be involved a predatory strategy of coiling, penetrating, lysis of the pathogen's cell wall. Beyond its antifungal potential, this beneficial microbe showcased plant growth-promoting attributes, like ammonia production, siderophore production (71.1%), phosphate solubilization (83%), and zinc solubilization (17.1%).Field trial conducted in two tea gardens of Dhubri District of Assam showed that 3 foliar spray of T. harzianum (A2S3) liquid bioformulation @10 ml/l, installation of yellow sticky trap (2 no./300 m2), removal of odd and damaged plant parts, regular weeding and irrigation showed effective in mitigating other insidious plant diseases such as Fusarium die back (15.3% and 0.7%) and grey blight caused by Pestlioptiopsis thea upto 6.5%, 20.4% respectively in Maa Phulaswari MTG and Saslapara NTG, Dhubri, Assam. The treatment also found to reduce the infections of RSM (10.3% and 17.1%) and TMB upto 4.3% and 8.2% in Maa Phulaswari MTG and Saslapara NTG, Dhubri, Assam respectively. Concurrently, it fostered a healthier ecosystem by improving plant growth parameters such as inter-node length, specific leaf weight, per cent moisture content besides soil physiochemical properties such as soil pH, soil EC by enriching soil organic carbon (1.6% and 1.2%) and stimulating microbial diversity (fungal- 76 and 106 cfu/ml, bacteria- 306 and 296 cfu/ml). The tea plant itself responded positively, with elevated levels of protective compounds phenol (208.54 ppm) and flavonoid (346.16 ppm) content in Maa Phulaswari mini tea garden and higher TSS (158.81 ppm) and TSP (115.73 ppm) in Saslapara new tea garden, Dhubri, Assam. Further research is warranted to evaluate the in- vivo efficacy and develop suitable formulations for field applications. This eco-friendly approach could offer a sustainable solution for tea disease management, reducing reliance on chemical fungicides.
650			_aTea _xBlister blight disease. _910305
650			_aDisease _xManagement _xBiocontrol. _910306
700			_aDutta,Pranab _eMajor Advisor. _95806
856			_uhttps://krishikosh.egranth.ac.in/handle/1/5810220893 _yOnline.
942			_2ddc _cTH
999			_c5711 _d5711