Diseases of Paulownia and their Management

Diseases of Paulownia, an exotic to India, have been studied in the nursery and young plantations and management of the potentially destructive diseases has been worked out. In all seven fungal diseases and one bacterial disease have been recorded on P. fortunei. They are damping-off caused by Rhizoctonia solani, ischolar_main and basal rot by Rusarium sp. And R. solani, leaf spotting and blight by Corynespora cassiicola, Cercospora sp. and Pseudocercospora sp and leafblight by R. solani and Phytophthora nicotianae. Of the above diseases ischolar_main and basal rot, Pseudocercospora and Corynespora leaf spotting and blight and leaf blight by Phytophthora nicotianae and R. solani are the diseases hitherto unknown and are reported for the first time. Root and basal rot, which is highly destructive and is responsible for routing the plantation at New Forest, has been successfully controlled through cultural practices involving mound planting or planting on raised strips and soil amendment by mixing sand with soil (1:1). Root/shoot cuttings if planted in February-March ensures the young crop free from ischolar_main and basal rot as the tissues become sufficiently mature by the time monsoon rains set in. Similarly, potting mixture with soil and sand (2:1) and 2 per cent well decomposed FYM is recommended to minimise the disease. A bacterial disease caused by a rod-shaped bacterium is the first record of the disease on P. fortunei. Cladosporium cladosporioides plastering the lower leaf surface and a sooty mold growing on the supper leaf surface are recorded. On P. tomentosa the diseases have been studied in the nursery only. Five fungal diseases recorded on this species are damping-off caused by Fusarium sp. And Rhizoctonia solani, leaf spotting and blight by Cercospora sp. Pseudocercospora sp. and Corynespora cassiicola and leafblight by P. nicotianae. Both Paulownia species show high susceptibility to Meloidogyne, the ischolar_main knot nematode. Use of deoiled neem cake @ 15 g/per pot is recommended to overcome the nematode problem in the nursery.