Use of nutrients on raised beds for increasing rice production in rice - wheat cropping systems

摘要

A study was conducted during three rice seasons on the Regional Wheat Research Center experimental field in Rajshahi, NW Bangladesh, to compare the effects of tillage options, nitrogen levels and management strategies on rice. In a strip-split plot design, two tillage systems were tested: manually prepared, permanent bed (PB- two other crops besides rice are sown per season on the same beds) and rice conventionally tilled on the flat (CTF). Within each tillage system, two nitrogen management practices were used: broadcast (BC) and furrow placement (FP) between rice rows. Three N levels, at 50%, 100% and 150% N ha~(-1) of recommended N levels (representing 40, 80 and 120 kg ha~(-1)) were used. The data indicate that, by using raised beds compared to conventional tillage, nitrogen uptake and efficiency can be increased. The maximum N uptake by the grain and total N uptake by the plant were recorded in PB, when the highest dose of N was applied. Permanent bed tillage systems also showed substantial water savings, 25% to 30%, over the CTF treatments. Thus, in warmer areas with multi-crop systems, where water resources are often limited and nutrient uptake and efficiencies are low, the use of raised beds in permanent bed cropping system would be a distinct advantage.