A split-plot experiment was conducted to determine the response of potato to application rate of biochar (0, 2, 4 and 6 t/ha , main plots) and number of irrigations (once, twice and thrice a month, sub-plots) in 3 replications as a pot trial in a screen house at Khumaltar during winter season of 2018 and 2019. Biochar was produced from Lantana camara by semi-pyrolysed technique in a Kon Tiki drum. Plastic pots with 26 cm of diameter were used to meet the 25 cm plant spacing of potato recommended in Nepal. The early maturing (90 days) released variety ‘Desiree’ was used for the trial. Observations were recorded on plant and tuber attributes. The results revealed that the influence of biochar rates was positive over zero biochar on plant height, root fresh weight, root dry weight, stem fresh weight and tuber dry weight. The effect of biochar @ 2/ha had similar effects to the rates of 4 t/ha and 6 t/ha rates. Irrigation treatments were significantly different for plant height, number of tubers per plant, root fresh weight, stem and leaf fresh weight, tuber fresh weight, root dry weight and tuber dry weight. Among the irrigation schedules, irrigating twice and thrice a month had similar effects but they were different from one irrigation. Interactions of biochar @ 2 t/ha with one, two or three irrigations were superior to the interactions of biochar @ 0 t/ha with one and two irrigations for tuber dry weight and total dry weight.

No abstract

A series of experiments were carried out to evaluate the performance of exotic potato clones including PRP lines at research field of Regional Agricultural Research Station (RARS), Parwanipur, Bara, Nepal during the winter seasons of 2017 and 2018. Thirty-nine potato clones were evaluated in initial evaluation trial and eleven clones were evaluated in coordinated varietal trial with check varieties Khumal Ujjwal and Kufri Jyoti. From the initial varietal trial in 2017, the highest tuber yield (21.54 mt/ha) was found in CIP389660.9 followed by CIP391046.14 (21.38 mt/ha). In 2018, the highest tuber yield (29.72 mt/ha) was produced in CIP392759.1 followed by CIP393085.5 (26.92 mt/ha) and CIP391046.14 (26.64 mt/ha). In 2018, the tuber yield was the highest (26.12 mt/ha) in PRP 266265.15 followed by CIP 393371.159 (24.79 mt/ha). In coordinated varietal trial carried out in 2017/18, the highest tuber yield was noted in CIP394600.52 (42.65 mt/ha) followed by CIP395443.103 (30.83 mt/ha) and CIP395445.16 (24.43 mt/ha) respectively. Whereas in 2018/19, the highest yield was produced by PRP266265.15 (26.12 mt/ha) followed by CIP393371.159 (24.79 mt/ha) and CIP 396012.266 (22.66 mt/ha) respectively. In RARS, Parwanipur conditions, CIP 394600.52, CIP 395443.103, CIP 395445.16 and CIP 304394.56 along with PRP 266265.15 were found to be superior to standard check variety. These potential genotypes need to be further verified in farmers field in additional districts of central Terai region before notifying in the national seed system. Adoption of these clones as variety may increase the potato production and improve the food, and nutritional security in the central Terai region of Nepal.