ASSESSMENT OF SOME SPICES AS MAIZE SEEDS PROTECTANTS AGAINST MAIZE WEEVIL, Sitophilus zeamais (MOTSCULSKY) [COLEOPTERA: CURCULIONIDAE]

Maize is cultivated in large quantity during the raining season in Nigeria. Maize is classified into fourth position of the most edible seeds after sorghum, millet and rice. Despite its importance as staple food, they are preservation at the time of abundance during the raining season is being hindered by maize weevil, Sitophilus zeamais which is the major insect pest of stored maize seeds. The toxicity of Aframomum melegueta, Monodora myristica and Syzygium aromaticum seeds powders and extracts were assessed in the Laboratory at ambient temperature of 28±2oC and 75 ± 5% relative humidity for the management of maize weevil, Sitophilus zeamais. The seeds dusts were tested at doses 0.2, 0.5, 1.0, and 2.0 g / 20 g of maize seeds. Oil extracts were tried at concentrations 0.2, 0.5, 1.0, and 2.0 ml. Parameters assessed includes mortality rate, progeny development, % weight loss, seeds damage and weevil perforation index (WPI) caused by maize weevils. The results of M. myristica powder caused 76.7% adult mortality at rate 2.0 g/ 20g after 24 hours of treatment. Syzygium aromaticum powder evoked 60% mortality of maize weevil. Aframomum melegueta powder evoked 53.3% adult mortality at rate 2.0 g / 20 g after 24 hours of treatment. Monodora myristica oil extract at concentration 2.0 ml/ 20g of maize seeds evoked 100% adult mortality after 24 hours of treatment. Syzygium aromaticum caused 86% adult mortality at concentration 2.0 ml/ 20g of maize seeds. Aframomum melegueta evoked 80% mortality at same concentration. Aframomum melegueta, Monodora myristica and Syzygium aromaticum seeds oil extracts prevented egg laying, progeny development, weight loss and seeds damaged. The integration of A. melegueta, M. myristica and S. aromaticum into the management of maize weevils will ensure availability of viable seeds for future farming and ensure food security in developing countries such as Nigeria.