Comparative Profitability of Managing Meloidogyne incognita on Cowpea (Vigna unguiculata) Using Carbofuran and Pulverized Aloe keayi Leaves

The cost-benefit of managing Meloidogyne incognita on cowpea (Vigna unguiculata) using leaves of Aloe keayi and carbofuran was evaluated in two field experiments at the University of Ibadan in Southwest Nigeria with the aim of selecting the more profitable management option. The experiments were laid out in a randomized complete block design and the treatments were: A. keayi at 80 kg/ha, carbofuran at 2 kg a.i./ha, untreated-infected control and uninfected control. Two-week old Ife Brown cowpea seedlings were inoculated with 10,000 eggs of M. incognita (except uninfected control). Air-dried milled leaves of A. keayi and carbofuran were applied one week after inoculation (WAI). Data collected at 10 WAI were: growth, yield, gall index (root damage), and Meloidogyne numbers. The costs and benefits of treatments were calculated. Treatment of M. incognita-infected cowpea with A. keayi and carbofuran improved vegetative growth by 201.6 % and 183.5%, respectively compared to untreated-infected cowpea. Root damage was reduced by 62.5% and 68.8% by A. keayi and carbofuran, respectively. A. keayi compared effectively with carbofuran in reduction of nematode population. Treated cowpea with A. keayi improved grain yield by 219.9% that translated to a gross margin (GM) of US$ 798.1 per hectare; whereas carbofuran gave a yield increase of 200.5% that translated into a GM of US$ 692.3 per hectare. Cost:benefit (CB) analysis showed positive return per hectare when cowpea was treated with A. keayi and carbofuran. Management of M. incognita on cowpea with A. keayi (CB=0.61) is more profitable than carbofuran (CB=0.74).