Effect of seed source, size and treatment on potato growth and yield

Abstract

In Uganda, the capacity of certified potato seed production is too low to satisfy the demand; a gap that has been filled with low quality seed from informal sources. This study was set up to determine the effect of seed source, size, and treatment on potato growth, yield and incidence of late blight disease. Using a randomized complete block design in a split-split-plot arrangement, field trials were conducted at three locations in South-western Uganda for two consecutive seasons. Seed source was at 3 levels: farmer-saved, local market, and certified seed; seed size at 2 levels: large 35 to 55 mm and small < 35 mm; and fungicide seed treatment at 2 levels: untreated and treated. Results showed that certified seed significantly had the highest values for plant height (60.89 cm), plant emergence (88.60 %), and yield of medium-size (2.79 t/ha) and large-size tubers (3.59 t/ha) and total tuber yield (8.60 t/ha). Large-size seed exhibited significantly higher performance than the small-size seed for plant height (59.03 cm), main stems per plant (2.83), and total tuber yield (7.89 t/ha). Fungicide-treated seed showed significantly better performance than the untreated seed for total tuber yield (7.77 t/ha). However, the fungicide seed treatment had no significant effect on potato growth parameters, and late blight incidence. Integrating large-size certified seed with fungicide treatment considerably improved potato yields. In case of unavailability of certified seed, carefully selected large-size farmer-saved seed with fungicide dressing may be the next option.