India is the largest producer (80%) and exporter (60%) of turmeric in the world. 1 Turmeric plants are propagated by vegetative method using mother and finger rhizomes. 2 The plant is seasonally affected by few major and minor pests which includes shoot borer, Conogethes punctiferalis
and leaf roller, Udaspes folus 3 and 4 which leads to major crop loss 5 observed U. folus harboring Elettaria cardomum, OSI-744 nmr Aframomum melegueta and Curcuma amada too. The larvae of this lepidopteron pest cause destruction in the plant leaf and cause considerable yield loss by 20–34%. Entomopathogenic fungi like Beauveria bassiana (Bals.) Vuillemin and Metarhizium anisopliae (Metsch.) Sorokin has been used successfully for managing insect pests in temperate regions. 6 The present study was aimed in developing a biopesticide click here against U. folus with rapid growth rate and high pathogenicity. The study was conducted in PTS turmeric variety which is a famous cultivar of India now preferred by most farmers for its high yield and its high tolerance to disease
and pest attack. Neem products are also used selectively in controlling pests of various economically useful plants. 7 The seeds contain a complex secondary metabolite azadirachtin which imparts a bitter taste. It acts as an anti-feedant, repellent and egg-laying deterrent, protecting the crop from damage. Similarly the leaves of Vitex negundo are also capable of causing mortality of lepidopteron pests. 8 So these two plant products were also used in the current study for comparison purpose. To keep in mind on all these parameters, studies were conducted to evaluate indigenous biocontrol agents to control U. folus under field conditions. Surveys were conducted in naturally infected turmeric farms to isolate and identify virulent entomopathogenic fungi infecting U. folus of PTS turmeric plants in Erode region, [11°20 N 77°431 E],
Tamil Nadu, India. The collections were made during September–November in 2010. The cadavers were collected in sterile glass second vials separately from which the pathogens were isolated using Potato Dextrose Agar (PDA) medium following standard mycological techniques. 9 Two fungi were subjected to 18S rDNA sequencing and BLAST and identified as Hirsutella citriformis and Nomuraea rileyi. The fungal sequences were deposited in NCBI (JQ 675289 and JQ 686668; respectively). Along with M. anisopliae and B. bassiana, which are commonly used entomopathogenic fungi; Standard H. citriformis (MTCC 6800) and N. rileyi (MTCC 4171) cultures were obtained from Microbial Type Culture Collection, Chandigarh, India and used for comparison studies. For B. bassiana, H. citriformis and M. anisopliae PDA medium and N. rileyi, Sabarouds Yeast Maltose Peptone (SYMP) medium was used for multiplication. Spore suspensions of each pathogenic fungus were prepared by using 80–100 ml of sterile distilled water containing 0.05% Tween 80 solution.