Temporal Dynamics and Seasonal Incidence of Major Insect Pests in Castor (Ricinus communis L.) under Tropical Agro ecosystem of Tamil Nadu
M. Senthilkumar
Horticultural Research Station, Yercaud, Tamil Nadu Agricultural University, Tamil Nadu, India.
M.Deivamani *
ICAR-Krishi Vigyan Kendra, Dharmapuri, Tamil Nadu Agricultural University, Tamil Nadu, India.
S.R.Venkatachalam
Tapioca and Castor Research Station, Yethapur, Tamil Nadu Agricultural University, Tamil Nadu, India.
P.Arutchenthil
Tapioca and Castor Research Station, Yethapur, Tamil Nadu Agricultural University, Tamil Nadu, India.
P.Kathirvelan
Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India.
P.Ayyadurai
Centre of Excellence for Millets, Tamil Nadu Agricultural University, Athiyandal, Tiruvannamalai, Tamil Nadu, India.
P. Senthilkumar
Regional Research Station, Tamil Nadu Agricultural University, Paiyur, Krishnagiri, Tamil Nadu, India.
K.Govindan
Regional Research Station, Tamil Nadu Agricultural University, Paiyur, Krishnagiri, Tamil Nadu, India.
K.Sasikumar
Regional Research Station, Tamil Nadu Agricultural University, Paiyur, Krishnagiri, Tamil Nadu, India.
*Author to whom correspondence should be addressed.
Abstract
An intensive four-year field study (2013–2017) was conducted at Tapioca and Castor Research Station, Tamil Nadu Agricultural University, to monitor the seasonal incidence and population dynamics of major insect pests infesting castor (Ricinus communis L.). Weekly observations revealed that leafhoppers (Empoasca flavescens) were the dominant sucking pest, initiating infestation from the seedling stage and peaking between the 50th and 52nd standard weeks. Defoliators such as Achaea janata, Spodoptera litura, Euproctis fraterna, and Ergolis merione appeared sporadically, with capsule borer (Conogethes punctiferalis) damage observed from spike initiation onward. Significant late-stage infestations of thrips (Retithrips syriacus) and whiteflies (Trialeurodes ricini) were also documented. Pest incidence patterns closely followed crop phenology and weather variables. The findings are crucial for designing location-specific Integrated Pest Management (IPM) strategies in castor agroecosystems.
Keywords: Castor, pest dynamics, seasonal incidence, Empoasca flavescens, Conogethes punctiferalis, thrips, weather correlation, IPM