Arrayed Rice Mat Seedlings for Saving Seeds: Focusing on Missing Hills and Hill Mortality

摘要

To save seeds over the same planting area as that of conventionally sown broadcast seedlings, arrayed mat seedlings were prepared by sowing seeds in 26-furrow arrays on coco-peat mats, transplanted with the use of a conventional 8-row transplanter and grown along the broadcast (control) seedlings. The arrayed seedlings were prepared with 40% less seeds than were the control and their foliar ages were 3 to 4 at transplanting. Neither seedling was suitable for a 7mm-vertical feed in terms of missing hills at transplanting. The arrayed seedlings at transplanting missed 11.3% and 6.3% of hills in the 10 and 13mm-vertical feed, respectively, but they were still larger than those in the control (9.0% and 3.3%). With the arrayed seedlings, the hill mortality during the growth period was low (>5%) and the grain yield was 500g/m~2, which were not different from the control.