Effects of Blended NPSB Fertilizer on Yield and Yield Related Traits of Potato (<i>Solanum tuberosum</i> L.) Varieties in Oda Bultum District, Eastern Ethiopia

Abstract

Potato is an important food and cash crop in eastern Ethiopia including Oda Bultum District. However, there is no information on the role of blended NPSB fertilizer required to produce tuber yield and tuber quality traits. A field experiment was conducted in Oda Bultum District, under rainfed during 2018 cropping season, with the objectives of assessing the effects of blended NPSB fertilizer rates on yield-related traits and tuber yield of potato varieties and to estimate the cost-benefit of the application of blended NPSB fertilizer in potato production. The treatments consisted of two potato varieties (Bubu and Gudanie) and six rates of NPSB (0, 100, 150, 200, 250 and 300 kg NPSB ha -1 ) fertilizer. The experiment was laid out as a Randomized Complete Block Design in a 6 x 2 factorial arrangement and replicated three times. Analysis of variance revealed that the two main factors; blended NPSB and variety had a significant effect on all traits except that fertilizer and variety had a non-significant effect on days to 50% emergence. Interaction of blended NPSB fertilizer and variety had a significant effect on total tuber number/hill, average tuber weight, total and marketable tuber yields (t ha -1 ). Gudanie variety emerged, flowered and matured earlier than Bubu. Early flowering of the crop was observed in a plot which did not receive fertilizer while the application of NPSB fertilizer delayed flowering and maturity of plants that received highest rates NPSB fertilizer (200, 250 and 300 kg ha -1 ). The highest total tuber number hill -1 (16.00) was obtained from Gudanie variety at the application of 200 kg ha -1 NPSB fertilizer. The highest proportion of small size tubers were obtained from plots than received no fertilizer while the largest proportion of large size tubers were obtained from plots that received 200, 250 and 300 kg ha -1 NPSB fertilizer. The highest total and marketable tuber yields of 30.55 and 27.22 t ha -1 , respectively were obtained from Gudanie variety with the application of 200 kg ha -1 NPSB fertilizer. Gudanie had a significantly higher specific gravity (1.085g/cm 3 ), tuber dry matter (21.98%) and starch content (15.82%) while plants produced tubers with highest specific gravity, tuber dry matter and starch content due to the application of 200 kg ha -1 NPSB fertilizer. Moreover, the highest net benefit of 116,330.24 Birr ha -1 with 4066% marginal rate of return were obtained from growing of Gudanie variety with the application of 200 kg ha -1 NPSB plus 100 kg ha -1 urea fertilizer that could be recommended for production of potato in the study area.

Vine Cutting Lengths and Fertilizer Effects on Yield of Sweet Potato (Ipomoea batatas L.)

“…Similarly, the addition of NPS fertilisation application enhanced the development of storage roots due to an increase in cell size, elongation, enhancement of cell division, nutrient absorption, photosynthesis and general physiological processes that subsequently enhanced root length and diameter as well. This result was in line with the work of Assefa et al 24 , who observed that the increasing application of blended NPSB fertilizer from 0-300 kg haG 1 significantly increased the percentage of large tuber size by about 141.63% in potatoes. A similar result also was observed by Pushpalatha et al 25 , who reported that the tuber length and diameter of sweet potato was found significantly highest during nitrogen fertilizer application.…”

“…This result was in line with the work of Nebiyu and Getachew 20 , who indicated that the highest (32.04%) and lowest (30.17%) dry matter content of sweet potato was recorded at 7 and 9-node numbers per cutting, respectively. Assefa et al 24 also reported the increase of tuber dry matter content with increasing application rates from 0 to 200 kg NPSB haG 1 probably due to storage accumulation and partitioning of more assimilates in potato tubers. The result agreed with Alemayehu and Jemberie 11 who confirmed that application of 283.75 kg haG 1 of blended NPS fertilizer recorded the highest tuber dry matter content in potato varieties tested than control plots.…”

Response of potato (Solanum tuberosum L.) varieties to blended NPSB fertilizer rates on tuber yield and quality parameters in Gummer district, Southern Ethiopia

“…Such observed prolonged in days to 50% flowering, as a result of increasing application of fertilizer might be attributed to the positive effect of nitrogen that stimulated growth and prolonged vegetative phase, and delaying the reproductive phase of plants with enhanced the uptake of nutrients including phosphorous (Khan et al, 2009). The current study's findings are consistent with those of other researchers who observed that increasing application rates of blended NPSB fertilizer extended days to 50% flowering of potato (Muluneh, 2018;Gezahegn et al, 2021;Tilaye and Diriba, 2021).…”

“…This implied the increment of NPSB fertilizer rates, which might positively respond to tubers' tuber initiation process and bulking rates, including tubers' size and shape. In agreement with this finding, Gezahegn et al (2021) found that when NPSB fertilizer rates increased from 0 to 300 kg ha -1 , the proportion of small sized potato tubers reduced by 53.67 to 19.94%, whereas increasing the rates of NPSB fertilizer from 0 to 200 kg ha -1 increased the proportion of medium sized tubers by 29.83 to 42.97%.…”

“…However, the local variety with the unfertilized plot had the lowest tuber number (7.65) and yield per hill (0.682 kg hill -1 ) (Table 8). This might be the genetic makeup of the crops varied in accumulation of food material accumulation (nutrient uptake), as well as photosynthetic activity response in the rates of blended NPSB fertilizer (Mekides et al, 2020;and Gezahegn et al, 2021). The cultivar had high nutrient uptake of genotypes which leads more fast growth, more foliage and increase in leaf area as well as induced the formation of bigger tubers thereby resulted in higher tuber number and yield per hill.…”