www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 202.141.127.50 on dated 17-Apr-2012 101 Indian J. Hort. 69(1), March 2012: 101-105 Comparative evaluation of pesticides and biorationals against key pests of greenhouse chrysanthemum Naved Sabir * , Sikha Deka, R.K. Tanwar, Balraj Singh ** , Sumitha Raj, Susmita Adhikari and S.S. Sindhu ** National Centre for Integrated Pest Management, Pusa campus, New Delhi 110012 ABSTRACT Chrysanthemum (Dendranthema grandiflora) is grown for year round flower production in greenhouses. Greenhouse experiments were conducted in Centre for Protected Cultivation Technology (CPCT), IARI, New Delhi for two seasons during 2009 - 2010 to study the efficacy of individual and integrated treatments for the management of key insect pests of chrysanthemum. Results revealed that in all the tested insecticides, the integrated treatments were most effective in comparison to the individual interventions. Combined treatment of phosphamidon and cypermethrin was the most effective for the key pests, viz. aphid and caterpillar. Efficacy of caterpillar management by spinosad increased after three days of application (94.44%) in comparison to first two days (13.20 and 30.33%, respectively) of application and it persisted up to 10 days of application which was not observed in controlling aphid. In chrysanthemum aphid control, the effectiveness of the treatment of agricultural spray oil and azadirachtin was decreased immediately after two 2 days of spraying, whereas combined treatment of both showed very effective result. Agricultural spray oil and azadirachtin are more acceptable than conventional insecticides as they are known to be active against pest populations but are relatively more environment-friendly to beneficial organisms. Key words: Chrysanthemum, greenhouse, agricultural spray oil, azadirachtin, Macrosiphoniella, Spodoptera, pesticides. INTRODUCTION Chrysanthemum ( Dendranthema grandiflora Borkh), has been recognized as one among the five commercially important potential flower crops in India (Janakiram et al., 7). However, under greenhouse its quality and production is adversely affected by insect pests such as aphid, caterpillars, mites, whiteflies, thrips and leaf miner. Among these pests, chrysanthemum aphid and spodopteran caterpillars were found to be the key pests in experimental greenhouses. Chrysanthemum aphid (Macrosiphoniella sanborni) is an important pest of chrysanthemum that causes direct damage through feeding resulting in wilting, leaf distortion, and transmission of several viruses; and indirect damage through physical contamination with aphid exuviae and honeydew which is a nutrient source of sooty mold (Agrios, 3). All of these factors together cause significant economic damage to chrysanthemum crops mainly flowers, by decreasing their beauty and marketability. Chrysanthemum caterpillar (Spodoptera litura) is another pest causing enormous losses. The use of good agricultural practices and integrated pest management (IPM) are being increasingly advocated in protected cultivation (Sabir et al., 14). Biorational pesticides such as agricultural spray oils and azadirachtin have shown to be effective against the most common polyhouse pests (Smith and Krischik, 15). Among the plants possessing environment-friendly compounds, azadirachtin is proving to be a valuable asset on account of its insecticidal properties (Abdullah, 2). It has been considered as an environmentally and toxicologically reduced risk material and has been embraced by IPM practitioners as a biorational pesticide (Williams et al., 17), which offers a new tool for insect resistance management (Thompson and Sparks, 16). Use of potentiating mixture is a useful strategy to combat insecticide resistance. There are some results, which strongly support the use of insecticides with different mode of action in mixtures in order to avoid the resistance development (Archer et al., 5; McKenzie and Byford, 9; Yamamoto et al., 18). The synergistic interactions may occur between the different components used in combination, leading to increased efficacy (Sayyad et al., 11). The present work is an attempt to evaluate the efficacy of insecticides, individually and or in combination for the management of aphids and caterpillars in chrysanthemum under greenhouse conditions. MATERIALS AND METHODS The experiments were conducted in the green house of Centre for Protected Cultivation Technology * Corresponding author’s E-mail: n_sabir@rediffmail.com **Centre for Protected Cultivation Technology, IARI, New Delhi 110012