Department of Vegetable Science, Dr YS Parmar University of Horticulture and Forestry, Nauni, Solan (H P)
National Symposium on “Plant Pathology in the Changing Global Scenario” held at National Bureau of Plant Genetic Resources, New Delhi on February 27–28, 2009
Ginger is an important spice crop of the family Zingiberaceae and is highly esteemed for its warm pungent taste and pleasant aromatic flavour. Among various pathogens infecting ginger, rhizome rot is a serious disease causing considerable economic losses to growers. A study was conducted to find the magnitude of pathogens responsible for rhizome rot. The results showed that maximum rotting was observed in rhizomes inoculated with Pythium as compared to Fusarium. Pathogenicity tests of Pythium, Fusarium and a combination of Pythium and Fusarium were also carried out on sprouts as well as on roots of ginger and maximum per cent rotting in sprouts and roots was recorded in samples inoculated with a combination of Pythium and Fusarium followed by only Pythium and Fusarium. Magnitude of pathogenicity of root knot nematode and its combination with Pythium and Fusarium was tested on ginger sprouts as well as on roots under laboratory conditions. The results revealed that maximum per cent rotting was recorded in Pythium + Fusarium + root knot nematode (40 – 70%) followed by Pythium + root knot nematode (25–40%) and Fusarium + root knot nematode (20–35%) while root knot nematode was least virulent in ginger sprouts. Similar pattern of pathogenicity was recorded on roots of rhizomes with a maximum rotting of 90 per cent by combined application of Pythium + Fusarium + root knot nematode, while least per cent rotting was recorded in root knot nematode. Among all bacterial isolates, isolate 7 of Ralstonia solanacearum was most virulent giving cent per cent disease incidence, while minimum was recorded in isolate 3. Isolates 2, 4, 5 and 6 gave 66 per cent disease incidence and were equally pathogenic.
