Planting geometry and dehaulming schedule affecting productivity of seed potato (Solanum tuberosum)

Abstract

A field experiment was conducted during the winter (rabi) season of 2014–15 and 2015–16 at the Punjab Agricultural University, Ludhiana, to study the effect of planting geometry and dehaulming scheduling on grade-wise productivity and economic returns of potato (Solanum tuberosum L.). The experiment was conducted in a split-plot design with 3 planting geometries (65 cm × 11.5 cm, 65 cm × 15 cm and 65 cm × 18.5 cm) as main plots and 3 dehaulming schedules in subplots [80, 90 and 100 days after sowing (DAS)] replicated thrice. The results showed that, planting geometry and dehaulming timings significantly influenced tuber-size distribution, grade-wise tuber yield and economic returns of the crop. Among the planting geometries, the highest yields of small (<35 mm) (6.63 t/ha) and medium (35–45 mm)-size tubers (15.92 t/ha) were recorded with the closer planting geometry (60 cm × 11.5 cm), which was at par with planting geometry of 65 cm × 15 cm. Contrarily, the highest yield of large size (>45 mm) tubers (22.29 t/ha) was obtained with the wider planting geometry (65 cm × 18.5 cm) and it was also at par with 65 cm × 15 cm. The highest net returns (`379,400/ha) were obtained with planting geometry 65 cm × 15 cm and the highest benefit: cost ratio with the wider planting geometry of 65 cm × 18.5 cm followed by 65 cm × 15 cm. The highest yield of small (7.19 t/ha)-and medium (16.15 t/ha)-size tubers were obtained with dehaulming scheduling at 80 DAS. However, delayed haulm cutting up to 100 DAS significantly increased the large size (24.84 t/ha) and total tuber yields (43.72 t/ha). The highest gross returns, net returns and benefit: cost ratio were also obtained with dehaulming at 80 DAS.