Performance of mechanically transplanted Basmati rice (Oryza sativa) under different age of seedlings and planting densities

A field experiment was conducted during the rainy (kharif) seasons of 2013, 2014, 2015 and 2016 at Ludhiana, Punjab, to study the effect of age of seedlings and planting density on growth and yield of mechanically trans- planted Basmati rice (Oryza sativa L.). Mechanical transplanting of 3-weeksold seedlings at 30 cm 12 cm spac- ing showed significantly higher plant height, dry-matter accumulation, leaf-area index and number of effective tillers/unit area than 3, 4 and 5-weeksold seedlings at 30 cm 16 cm. The grain yield of mechanically trans- planted 3-weeksold seedlings at 30 cm 12 cm spacing was 4.1 and 12.1% higher than 30 cm 14 cm and 30 cm 16 cm spacing respectively. Although the grain yield under mechanical transplanting of 3-weeksold seed- lings at 30 cm 12 cm spacing was statistically similar with manual transplanting at 20 cm 15 cm and 30 cm 12 cm, but the net returns and benefit: cost ratio of mechanically transplanted 3-weeksold seedlings at 30 cm 12 cm spacing ( 77.58 103/ha and 3.61) were significantly higher than manual transplanting at 20 cm 15 cm ( 71.50 103/ha and 2.87) and 30 cm 12 cm ( 72.27 103/ha and 2.90) spacing, respectively.