Glory lily ( Gloriosa superba) is a popular medicinal plant which is commercially exploited for export of seeds, useful in treatment of gout, and muscular inflammations.

Tamil Nadu leads in production of glory lily with an annual production of 800 tons of dry seeds.

Its cultivation has extended up to 2500 ha with major regions comprising Tirupur, Erode, Dindugal, Karur, Ariyalur and Nagapattinam districts.

Foreign exchange

The annual foreign exchange through export of glory lily seeds is estimated to be Rs.100 crores.

Even though better returns are expected in this high value crop, it is severely infested with leaf blight disease caused by the fungal pathogens viz., Curvularia lunata and Alternaria sp .

The severity of the infection is more during cloudy weather to the extent of 20 to 60 per cent

Symptoms

The disease appears in the form of small narrow elongated spots in the initial stage, and in due course, they extend along with the leaf.

In older plants, the typical symptoms are long elliptical necrotic lesions, with straw coloured centre and brown margins

The lesions can be several centimetres long and wide and in advanced stages, several spots coalesce on the leaves, destroying large areas giving the crop a distinctly blasted appearance.

Symptoms may appear in all stages. Initially, small, pale to brown, irregular or round spots may appear on the leaves. Each spot has a central necrotic lesion with concentric rings

In advanced stages, several spots coalesce together to form large blighted areas.

Management methods

Remove the infected plant debris from the field

Spray Mancozeb at 0.2 per cent concentration or Propiconazole (0.1 per cent) or Hexaconazole (0.1 per cent) at the time of infection.

The fungicidal spray has to be repeated four to five sprays at 15 days interval to check the leaf blight severity in this crop.

Spray 0.5 per cent ZnSO {-4} two times at fortnightly interval staring from 45th day after planting.

Dr. K. Rajamani

Prof and HeadDepartment of Medicinal and Aromatic CropsTamil Nadu Agricultural University, Coimbatore