Response of potato to nitrogen and phosphorus fertilizers at Assosa, western Ethiopia

Abstract

Low soil fertility is one of the critical factors limiting the productivity of potatoes (Solanum tuberosum L.) in western Ethiopia. The field experiment was conducted in the 2015 and 2016 cropping seasons to elucidate the response of potato yield, yield components, tuber quality to nitrogen and phosphorus fertilizer, and their economic benefit. The treatment comprised five levels of nitrogen (0, 50, 100, 150, and 200 kg N ha −1 ) and five levels of phosphorus (0, 50, 100, 150, and 200 kg P 2 O 5 ha −1 ). The experiment was laid out as a randomized complete block design in a factorial (5 × 5) arrangement and we replicated the treatments three times. The results revealed that the interaction of nitrogen and phosphorus did not affect growth, yield, and quality parameters of potato. However, nitrogen alone affected plant height, tuber number per plant, number of stems per hill, and marketable and total tuber yield, but not tuber quality parameters. The optimum yields of both marketable (25.5 Mg ha −1 ) and total (28.4 Mg ha −1 ) tuber yields were observed in the application of 150 kg N ha −1 . Phosphorus treatments had no response for most of the yield, yield components, or tuber quality parameters. Applications of 150 kg N ha −1 provided a maximum gross margin ($5138.68 or 141,773.55 Ethiopian Birr [ETB] ha −1 ) with a 79.4% gross profit margin and the highest benefit-cost ratio (4.86).

Effects of supplemental irrigation on yield, water use efficiency and nitrogen use efficiency of potato grown in mollic Andosols

“…The highest plant height, 76.82 cm, was recorded under N3. This increase of plant height with N dosage was also reported in previous research (Godebo and Belay 2020;Setu and Mitiku 2020;Tolessa et al 2017). Sebnie et al (2021) indicated that an application of mineral N fertiliser increased potato plant height compared to unfertilised plots.…”

Effect of Supplemental Irrigation on Tuber Yield, Water Use Efficiency and Nitrogen Use Efficiency of Potato (Solanum Tuberosum L.) Grown in a Mollic Andosol

“…The same comparison across the N fertilization treatments showed an increase in plant height with an increase in nitrogen rate. The same result was found by previous research (Tolessa et al, 2017;Godebo and Belay, 2020;Setu and Mitiku, 2020). The number of branches/plant and HI significantly increased with an increase in nitrogen rate (table 7).…”

Performance of apical rooted cuttings of potato grown in Mollic Andosols under different nitrogen fertilization and irrigation regimes

“…These results are not in agreement with the findings of Fandika et al (2016) andEl Mokh et al (2015), who reported that potato tuber number per plant increased with irrigation amount. These findings aligned with those of Ayyub et al (2019) and Setu and Mitiku (2020), who also found that an increment in the amount of N statistically increased tuber number plant. Moreover, El Mokh et al (2015) indicated that a low tuber number per plant decreased the total potato tuber yield.…”

“…The maximum marketable tuber yield of 54.25 t ha À1 achieved in Mollic Andosols of this study can be attributed to the significant interaction effect observed between the two factors. This finding confirmed the results of Zewide et al (2012), Getie et al (2015), El Mokh et al (2015, Regassa et al (2016), Ayyub et al (2019), Setu and Mitiku (2020) and (Tang et al, 2021), who reported that marketable potato yield significantly increases with N dosage. This study suggests further research using higher N rates above the rates used to find the N level from which an increase in the amount of N in Mollic Andosols might decrease potato yield.…”