Improving Rice Yield in Tidal Floodplain: Optimizing Seedling Age and Transplanting Date

Abstract

Major constraint of growing rice in south central coastal region of Bangladesh is the tidal submergence of land and crops. Indigenous rice is generally grown in tidal floodplain harvesting poor yield. Transplanting seedlings of optimum age on appropriate date may potentially increase rice yield. We carried out on-farm trials for evaluating growth and yield performance of two indigenous rice varieties (Sadamota and Lalmota) and a high yielding variety (BRRI dhan 44) in response to variable seedling age and transplanting dates for two years. In the first year, 45 d and 60 d old seedlings of Sadamota were transplanted on a single date either in rows at 40 cm x 40 spacing or following farmers' traditional practice of random transplanting. The second year's trial compared the performance of one indigenous variety Lalmota and one modern variety BRRI dhan 44. Two age groups (45 d and 60 d) of seedlings of Lalmota and single age group (45 d) of BRRI dhan 44 were transplanted on two different dates (August 8 and August 24). First year's trial results indicated that irrespective of seedling age, transplanting in rows produced higher yield compared with farmers' traditional practice. In the second year's trial, late transplanting of 45 d old seedlings of both the varieties gave higher yield compared with early transplanting. BRRI dhan 44 produced significantly higher yield than Lalmota. Late transplanting of 60 d old seedlings of Lalmota produced higher yield than transplanting younger seedlings. Lower yield of earlier planted rice was associated with greater hill mortality and seedling damage, and production of relatively lesser number of tillers and panicles. For increasing yield in tidal floodplain, late planting (late August) with 60 d old seedlings of indigenous varieties in rows (40 cm x 40 cm) has been suggested.

Improving Grain Yield of Indigenous Rice in Tidal Floodplain of Southern Bangladesh: Effect of Seedling Age and Transplanting Method

“…Seedlings of indigenous varieties grow faster and taller than modern varieties. Our earlier findings [34] indicated that depending on toposequence 45 -60 day-old seedlings of indigenous varieties grow sufficiently taller to cope with depth of tidal flooding immediately after transplanting. Seedlings older than 33 days up to 55 days give better yield under late transplanting for long duration varieties [35].…”