MANAGEMENT OF STRIGA IN FINGER MILLET (Eleusine coracana) BY INTERCROPPING WITH DESMODIUM (Desmodium intortum)

Abstract

Striga hermonthica (Del.) Benth is one of the major constraints affecting finger millet production in western Kenya causing significant yield losses. Research efforts have resulted in production of some improved finger millet varieties whose yield potentials remain unexploited due to susceptibility to Striga. High yielding improved finger millet variety P-224 is among the most susceptible varieties to Striga attack. Previous studies have shown positive results of intercropping maize with Desmodium spp. in efforts to control Striga and stem borers. Recent studies have also shown similar responses when a local finger millet variety was intercropped with Desmodium spp. This study was aimed at evaluating the potential Green leaf Desmodium (Desmodium intortum) to suppress Striga and improve yield when intercropped with improved finger millet varieties. Trials were set up on-station at Kenya Agricultural and Livestock Research Organization’s Alupe centre (KALRO-Alupe) and on-farm at Okiludu in Teso South using a Randomized complete block design in a split-plot arrangement over two seasons (2013 short rains and 2014 long rains seasons). Treatments consisted of four improved finger millet varieties namely Gulu –E, U-15, P-224 and Okhale -1 intercropped with Green Leaf Desmodium (Desmodium intortum) and compared with finger millet mono crop plots. Varieties were assigned to main plots while the cropping system (intercropping and mono-cropping) to sub-plots. The most susceptible variety to Striga; P-224 was the control. Data was collected on Striga counts, plant height, basal tillers and yield. Soil analysis was carried out at the beginning and end of the trials to ascertain initial soil status and monitor any soil chemical changes due to the cropping system thereafter. Results in this study indicated no consistent evidence to show that intercropping finger millet varieties with Desmodium intortum suppressed Striga at the two sites during the two seasons tested. Striga density however differed across seasons. Lower Striga counts were observed during the long rains season (35.9 Striga plants/plot) plants while higher Striga counts (151.4 Striga plants/plot) were observed during the short rains season. Intercropping neither increased nor reduced finger millet yield. Finger millet yield however differed significantly across planting seasons where higher yield (1.1t/ha) was observed during the long rains season and low yield (0.6t/ha) during the short rains season. Finger millet yield was also influenced by soil nutritional status. Farmers at Alupe and Teso sub-counties are advised to consider planting finger millet during the long rain season when soil moisture is adequate and Striga density lower as this leads to improved yield. It may also be worthwhile to consider conducting the trial over a longer period of time with involvement of more farmers to further investigate the potential of Desmodium intortum for Striga suppression in improved finger millet varieties.