Prevalence of seed borne mycoflora in commercially cultivated wheat varieties and management of black point disease caused by Bipolaris sorokiniana Tripathi Varsha1, Beg Mirza Jaish2,*, Singh Dinesh3 1ICAR-Indian Institute of Seed Science, Kaithauli, Kushmaur, Mau, Uttar Pradesh, India 2Department of Botany, Shibli National College, Azamgarh, Uttar Pradesh, India 3ICAR-Indian Institute of Sugarcane Research, Lucknow, Uttar Pradesh, India *Corresponding author
Online published on 24 May, 2018. Abstract In the study, two sets of seed samples viz., untreated and surface sterilized of different wheat seed samples were examined for the associated seed borne mycoflora by employing the Standard Purity Work Board and Standard Blotter Paper Method. The native best performing isolates of Trichoderma for their viability on different formulations and effect of suitable formulation on black point management studies were also studied. Dry Seed Examination (a non-destructive) method of detection, variety Raj 4037 was rated as resistant to seed-born mycoflora with 93.20% healthy seed, 00.70% deformed seed, 03.30% wrinkled seed, 02.00% discoloured seed and 00.80% fruiting body seed and variety WH 711 was rated as susceptible. Maximum 15 numbers of mycoflora viz., Bipolaris sorokiniana, Alternaria alternata, Alternaria triticina, Curvularia lunata, Curvularia pallescens, Fusarium oxysporum, Macrophomina phaseolina, Trichoderma hamatum, Cladosporium cladosporioides, Epicoccum purpurascens, Nigrospora oryzae, Aspergillus flavus, Aspergillus niger, Penicillium spp. and Rhizopus spp. were found associated by Standard Blotter Paper Method with the variety HD 2733 under untreated condition. Whereas Raj 4037 yielded minimum 8 numbers of pathogenic mycoflora. Talc powder (St.) formulation was found best for storage over long period of time followed by Talc powder (Us.) formulation. It recorded 21.1110g−1 at IAP, 14.7710g−1 at 30 DAP, 76.569g−1 at 60 DAP, 58.988g−1 at 90 DAP and 65.846g−1 CFU at 120 DAP whereas Talc powder (Us.) formulation recorded 17.7810g−1 at IAP, 13.2510g−1 at 30 DAP, 68.209g−1 at 60 DAP, 48.738g−1 at 90 DAP and 56.376g−1 CFU at 120 days after preparation (DAP) and these two formulation were rated as best formulation out of eight type of T. harzianum formulation. Out of best five formulation (on the basis of shelf life) tested for black point management, Talc Powder (St.) formulation was rated best, recorded significantly superior over the others with 78.00% seed germination, 83.10% shoot length, 11.63 cm spike length, 24.60% back point incidence, 42.18 qtls/ha yield and 44.50 g test weight followed by Vermiculite formulation on the susceptible variety HD 2733. Top Keywords Wheat, Black point disease, Bipolaris sorokiniana and Trichoderma harzianum. Top |