Botanical preparations for the protection of stored rice seed Oryza sativa from rice weevil Sitophilus oryzae and their impact on Oryza sativa germination
Seed Science and Technology
Institute of Natural Resources (PN433), Massey University, Private Bag 11222, Palmerston North, New Zealand; International Institute of Tropical Agriculture (UTA), Ibadan, Nigeria; C/o IITA Ltd, Carolyn House, 26 Dingwall Road, Croydon CR9 3EE, United Kin
Protection of seed from pest and disease damage, and the maintenance of seed quality during storage between harvest and planting are key issues for peasant farmers. Rice weevil (Sitophilus oryzae) is one of the main causes of loss of seed quality in rice (Oryza saliva). Treatment of stored rice with Azatin® XL (active ingredient azadiractin), neem (Azadirachta indica) seed powder and lentil (Lens culinaris cv. "Raja") seed powder gave some protection from rice weevil damage. Azatin® XL applied at a rate of 0.5% v/w rice seed gave effective short-term control of rice weevil without reducing rice seed germination. However, Azatin® XL applied at a rate of 2.0% (v/w) reduced rice seed germination. A. indica and lentil seed powders at the rate of 1.0% (w/w) and 2.0% (w/w rice seed) respectively gave effective protection against rice weevils with no reduction in seed germination. Pepper (Capsicum chinensis cv. "Habanero") fruit powder was ineffective against rice weevils. A relative humidity (RH) of 43% or lower in the seed storage environment and a reduction in seed moisture content (SMC) below 10% enhanced the mortality of rice weevils on rice seed.
Azadirachta indica; Capsicum; Capsicum chinense; Lens culinaris; Oryza; Oryza sativa; Raja; Sitophilus oryzae