Title: DESIGN - Strip-split-split plot with 3 replications at each of two Bangladesh Agricultural research station sites (Dinajpur - sandy loam soil; Rajshahi - silty clay loam soil). A triple crop rotation of wheat (Triticum aestivum) - mungbean (Vigna
1Challenging Tradition Permanent Raised Beds for
the Rice-Wheat Cropping System A.M. Talukder1,
M.I. Hossain1, M.A. Sufian1, J.M. Duxbury2, J.G.
Lauren2, C.A. Meisner3 1 Bangladesh Agricultural
Research Institute 2 Cornell University 3 Int.
Maize Wheat Improvement Center
Research funding from the
INTRODUCTION
RESULTS DISCUSSION
Raised bed agriculture is widely used in
developed countries and has proven to be an
excellent option for wheat in Mexico
(Limon-Ortega et al., 2000)1. Permanent raised
beds may also offer good possibilities for the
rice-wheat system of South Asia. Without tillage
(only reshaping), beds would allow soil
aggregation to be rebuilt over time, provide
deeper rooting, and better air/water
relationships in the soil. Particularly
attractive are the possibilities that water use
can be reduced, as furrow irrigation is more
efficient than flood irrigation, and that
fertilizer N recovery can be increased for both
rice and wheat by banding nitrogen into the soil
between two rows on a bed. 1 Limon-Ortega,
A., K.D. Sayre, and C.A. Francis. 2000. Wheat
nitrogen use efficiency in a bed planting system
in Northwest Mexico. Agron. J. 92303-308.
Weed Counts (/ m2)
FLAT
FLAT
MUNG '01
RICE '01
WHEAT '02
- WEEDS
- At Rajshahi, weed pressure was reduced in PB
compared to CT treatments in each of the three
crops in the rotation. Similar weed observations
were made at Dinajpur.
BED
BED
RICE
WHEAT
METHODS
RAJSHAHI
DINAJPUR
DESIGN - Strip-split-split plot with 3
replications at each of two Bangladesh
Agricultural research station sites (Dinajpur -
sandy loam soil Rajshahi - silty clay loam
soil). A triple crop rotation of wheat (Triticum
aestivum) - mungbean (Vigna radiata) - rice
(Oryza sativa) were grown in 2001 and
2002. TREATMENTS Main Plot -
Permanent raised beds (PB)
(15 cm high, 75 cm furrow to furrow - 2 rows
per bed) - Conventional
flat (CT) Sub-Plot - Band placed
nitrogen - Broadcast
nitrogen Sub-sub Plot - 50 recommended
nitrogen - 100 recommended
nitrogen - 150 recommended
nitrogen
- YIELDS
- Yields from the PB treatments were significantly
higher than those from the CT planting
configuration for all crops, at both sites (p lt
0.05). - Mean wheat and mungbean yields from the PB
treatments were 17-34 and 12-20 higher than
yields from CT plots, respectively. - Rice yields were 39-41 higher on beds than those
from conventional treatments. - Few differences in crop yields were attributed to
nitrogen placement at either site.
- NITROGEN RECOVERY
- With a few exceptions, wheat and rice yields from
CT treatments were less responsive to fertilizer
N than from the PB treatments at both sites. - However without a zero N level control to
determine soil N contributions, it is unclear
whether bed planting improved fertilizer nitrogen
recovery over the conventional flat practice. - Wheat 2001 grain and straw N contents were not
significantly different between treatments at
either site.
- IRRIGATION
- Despite no puddling and a sandy soil texture, 17
less supplemental irrigation was required in the
PB treatments relative to CT at Dinajpur during
rice 2001(2025 L vs. 2430 L). - Water supplied to wheat on PB at Rajshahi in
2001, was 66 of that applied to CT.