Studies on rhizome rot of ginger Zingiber officinale Rosc in Marathwada region

Abstract

Zingiber officinale Rosc. Is one of commercially important medicinal plant newlinebelonging to family Zingiberaceae viz. cultivated as a spice crop. Rhizome of ginger newlineis infected by many pathogens. Among this rhizome rot is one of the major problems newlinein ginger cultivation viz. caused by Fusarium solani (Mart.) Sacc. and Pythium newlineaphanidermatum (Edson) Fitzp. newlineThe healthy and infected samples were collected from different regions of newlineMarathwada i.e., Parbhani, Hingoli, Nanded, Beed, Latur, Jalna and Aurangabad. newlineThe symptoms of rhizome rot were studied from infected rhizomes. The newlineisolation of the pathogens was carried out from the infected rhizome samples and the newlinepathogens isolated were Fusarium solani (Mart.) Sacc. and Pythium aphanidermatum newline(Edson) Fitzp. newlineThe purification of pathogens was carried out by hyphal tip method and pure newlinecultures were obtained. The identification of pathogens was carried out one the basis newlineof culture, morphological and reproductive structure of the pathogens and confirmed newlineby ITS sequencing of the pathogens. newlinePathogenecity was proved by pot method in which rhizomes were planted in newlinethe pot and were inoculated with fungal pathogens till the appearance of the newlinesymptoms of rhizome rot. newlineThe biochemical changes due to fungal pathogens in rhizome content was also newlinestudied. The crude fibre, Gingerols and shagaols, oleoresin, volatile oil, non volatile newlineether extract, alcohol soluble extract, cold water soluble extract, total ash, water newlinesoluble ash and acid insoluble ash content of infected rhizome was decreased due to newlinefungal infection and only starch content increased in the infected rhizomes. GC-MS newlineanalysis was also carried out to know the phytoconstituents present in the healthy and newlineinfected rhizome samples. The total numbers of compounds identified in methanol newlineextract of healthy ginger rhizome were 30. In infected ginger rhizome 28 newlinephytochemical compounds were identified. newlineThe sensitivity of eight fungicides including systemic and non-systemic viz., newlineCarbendazim, Carboxin, Ridomil, Thiophenate methyl, Chlorothalonil, Copper newlineoxychloride, Mancozeb and Thiram was tested in vitro and in vivo against rhizome rot newlinepathogens Fusarium solani and Pythium aphinderatum at different concentrations. newlineAmong all fungicides, Carbendazim was most effective to control in vitro growth of newlineFusarium solani at 0.1% concentration. Similarly, Ridomil at 0.1% reduced maximum newlinemycelial growth of Pythium aphanidermatum. newlineThe fungicides were also tested in vivo against at the pathogens at the above newlineconcentration which exhibited significant growth inhibition by pot experiment. newlineCarbendazim at 0.1 % was found to be most inhibitory to Fusarium solani and newlineRidomil at 0.15 % was most effective against Pythium aphanidermatum. newlineThe bioefficacy of eight different plant leaves aqueous and methanol extract newlineviz., Azadirachta indica, Allium cepa, Cassia fistula, Lantana camara, Ocimum newlinesanctum, Tridax procumbens, Mentha arvensis and Allium sativum were tested in newlinevitro and in vivo against growth of Fusarium solani and Pythium aphanidermatum newlinecausing rhizome rot of ginger. newlineThe efficacy of these eight plant leaves aqueous and methanolic extract was newlinestudied in vitro at different concentrations as 0.0 (control), 10, 20, 30 and 40 %. The newlinemaximum inhibition of Fusarium solani was found due to methanol leaves extract of newlineAzadirachta indica treatment and Ocimum sanctum against Pythium aphanidermatum. newlineIn the in vivo study of efficacy of plant leaves extract by pot experiment newlineAzadirachta indica showed maximum inhibition of mycelial growth of Fusarium newlinesolani and Oscimum sanctum plant leaves extract in case of Pythium newlineaphanidermatum. newlineThe in vitro and in vivo study of effect of different biocontrol agents i.e., newlineTrichoderma harzianum, Trichoderma viride, Trichoderma hamantum, Trichoderma newlinevirens and Trichoderma koningii was evaluated against Fusarium solani and Pythium newlineaphanidermatum. In the in vitro and in vivo study, Trichoderma viride shows newlinemaximum inhibition of growth of Fusarium solani and Trichoderma harzianum newlineagainst Pythium aphanidermatum. newline