Yield studies on mechanically transplanted mat nursery of paddy raised under different irrigation systems relevant to Asian countries

To reduce labour dependence and develop an easy method for raising healthy nursery seedlings, mat nurseries of three paddy varieties were raised under drip, sprinkler and flood irrigation systems during three seasons and field evaluation was carried out after transplanting. The root length was maximum (6.22–6.45 cm) in nursery of all varieties for flood irrigation. The mat thickness (2.51–2.56 cm) and shoot length (10.90–11.60 cm) were maximum for sprinkler system among different varieties. Nursery water requirement (21.08–27.15 l.m⁻²) was minimum for and drip system for three varieties. Number of tillers per hill (24–25) were maximum for nursery raised under sprinkler irrigation system. The maximum mean grain yield (6.46–6.95 t ha⁻¹) after mechanical transplanting was recorded for nursery of all varieties raised under sprinkler system. Shoot length, number of hills m² and number of tillers per hill had detrimental effect on paddy grain yield whereas effect on root length, spike length, hill missing and as well as hill mortality were undetectable. For nursery raised under sprinkler irrigation system, mean grain yield was maximum (6.74 t ha⁻¹) mean minimum number of hills per m² (22.11), maximum number of tillers per hill (24.44), maximum shoot length (11.25 cm) and for mat thickness between 2.49–2.55 cm in all varieties.