Effect of inflorescence removal and time of earthing-up On growth, yield and quality of potato (solanum tuberosum l.) At jimma southwestern Ethiopia

Abstract

Potato is a high potential food security crop in Ethiopia. However, yield and productivity of the crop has been far below the world average. This is due to several factors including inappropriate agronomic practices, such as time of earthing-up and inflorescence management. Field experiment was conducted at Jimma, Southwest Ethiopia during 2016/17 under irrigation to determine the effect of time of earthing-up and inflorescence removal on growth, yield and quality of potato. The treatments consisted of time of earthing-up (no earthing-up, earthing-up at 15, 30 and 45 days after complete plant emergence) and inflorescence removal (inflorescence removed and not removed). Potato variety (Belete) was used for this experiment. A 2x4 factorial experiment was laid out with 3 replications. Data collected on growth, yield and quality components of potato were analyzed using SAS Version 9.3 statistical software. Inflorescence removal affected majority of the growth and yield parameters, while time of earthing-up affected all growth, yield and quality (green tuber number) parameters. The tallest plant height (87.3 cm) and the largest number of main stem per plant (4.3) was recorded from plants that received earthing-up at 15 days after plant emergence. The widest plant spread (64.83 cm), the largest leaf area (37cm2 )and the largest stem diameter (7.8 cm) were recorded from plants that received earthing-up at 15 days and inflorescence removal. Likewise, earthing-up at 15 days, combined with inflorescence removal, gave the maximum marketable tuber yield (35.83 ton/ha), and the highest average tuber weight per plot (120.37g). The highest total tuber yield (41.6 ton/ha) was recorded from plants that received earthing-up at 15 days combined with inflorescence removal, followed by earthing-up at 30 days combined with inflorescence removal (37 ton/ha), earthing-up at 45 days combined with inflorescence removal (33 ton /ha)and no earthing-up (31 ton /ha). The least number of green tubers per hill (1.47) was recorded from earthing-up at 15 days after complete plant emergence. Earthing-up at 15 days in combination with inflorescence removal (at 60 days after complete plant emergence) gave better plant growth, maximum tuber yield of Belete potato variety under irrigation condition. Since the current research was conducted at one location, in one season, and with one potato cultivar (Belete), it would be advisable to repeat the experiment so as to arrive at a final conclusion and subsequent recommendation