S.N. Kihara, D.M. Gikaara, E.M. Kamau, M.W. Gateri , N.M. Maina, A.N. Muriithi
Mobydick has important pest challenges, including root-knot nematodes, and being recently domesticated, its pest management is guided by borrowing practices applied in other crops. To enhance efficiency of available nematode management strategies, a survey was carried out to establish farmers’ awareness of root-knot nematodes of mobydick and their management. Purposive and random sampling was used to select Murang’a, Nyeri and Meru counties and households, respectively. In an on-station experiment to determine the best nematicide application regime for management of nematodes, VYDATE10G® was applied at variable regimes: two weeks pre-planting, at planting, and at 12 and 20 weeks after planting. Survey data subjected to correlation or analysis of variance (ANOVA). Results showed that 10% of the farmers in Meru propagated own planting materials compared to 50% in Murang’a and Nyeri Counties, while 50% source from neighbours. About 10% farmers sort seedlings; 1% treat the roots against nematodes before planting while only 2% considered soil health during nursery and field site selection one year rotation was common in all areas with maize (40%) or other crops (60%). Majority (96%) farmers applied nematicide at planting only while 4% applied at both planting and at flowering. There was correlation, r(21)=-0.506, p=0.014 between number of nematicide applications and nematode population in the soil samples and yield. Nematicide application regime in which combination was pre-plant, after 12 weeks and then 20 weeks outperformed other treatments. Compared to control, mean height and number of branches at flowering increased by 40% and time to flowering reduced by 20% while number of harvestable stems and their mean length increased by 25%. Overall, nematode population decreased by 72%. All the parameters differed significantly (p<0.05) compared to other treatments. Soil pre-treatment plus increased nematicide application frequencies were better for nematode reduction and increased yield. Results show that integration of chemicals with cultural practices such as crop rotations and antagonistic plants should be explored.
Kihara, S.N., Gikaara, D.M., Kamau, E.M., Gateri , M.W., Maina, N.M. and Muriithi, A.N. (2015). EFFECT OF NEMATICIDE APPLICATION RATES AND FREQUENCIES ON CONTROL OF ROOT-KNOT NEMATODES IN MOBYDICK. Acta Hortic. 1077, 13-21
DOI: 10.17660/ActaHortic.2015.1077.1
mobydick, nematodes, management, nematicide, application regime

Acta Horticulturae