Accepted 27th June, 2014
Time of sowing, plant spacing and variety have paramount significance in improving pod yield, quality and disease severity of green beans. The aim of the study was to determine appropriate sowing time, optimum plant spacing and appropriate varieties and their combination for better productivity of green beans under the humid tropical conditions of Jimma, southwestern Ethiopia. The treatments were five level of spacing (50 cm x 7 cm, 40 cm x 15 cm, 40 cm x 10 cm, 40 cm x 7 cm, 30 cm x 15 cm); four level of time of sowing (July 3rd, July 18th, August 2nd and August 17th) and two pipeline varieties, namely Melka-1 and Melka-5. The experiment was conducted in randomized complete block design with three replications in the 2010/2011 main cropping season. Analysis of variance has shown that most of the yield and yield components studied (pod length, pod diameter, number of pods, average pod weight and number of pods) were significantly affected by the interaction effects of variety and time of sowing. Marketable pod yield was however affected only by the main effects of time of sowing and spacing regardless of the varieties. Hence, the longest pod (13.5 cm) with a wide diameter (0.9 cm) was obtained from variety Melka-1 sown in mid July. The highest marketable pod yield (4,326 kg ha-1) was harvested from plants sown early July (which was on par with Mid July) and spaced at 40 cm x 7 cm. Our data suggested that mid July seems the most appropriate time of sowing and a spacing of 40 cm x 7 cm is adequate for green been production in the humid tropical conditions of Jimma irrespective of the varieties.
Keywords: Green bean, plant spacing, sowing date, pipeline varieties and marketable pod yield