On-going feasibility study of

1
On-going feasibility study of System of Rice
Intensification (SRI) in Bhutan
Lhendup, Karma, Lecturer, Sherubtse College,
Royal University of Bhutan, Kanglung
Results and Discussion
Introduction
The evaluation trials on SRI have been initiated
this rice growing season in Bhutan and the final
crop cut is yet to be done. Therefore, the actual
performance of these trials cannot be reported.
However, some of the yield contributing
parameters on SRI trials (taken recently) as well
as conventional method in three sites are
reported (Table 1).
Rice is one of the important food crops for the
people of Bhutan. Different varieties of rice,
both local and introduced are grown in a wide
range of elevation from subtropical lowlands (150
m) in the south up to elevations as high as 2600
masl in the north. The present productivity of
rice of less than 3 ton/ha cultivated in 46,585
acres out of 69,414 acres of irrigated land has
not been able to attain food sufficiency level in
the country (MoA, 2004). For the first time in
Bhutan, feasibility study through evaluation
trials on System of Rice Intensification (SRI)
has been initiated. This method is known to have
advantages for small and marginal farmers in
terms of economic and environmental benefits as
compared to the conventional method. This
presentation is focused on the preliminary
results based on the contributing yield
parameters from the on-going evaluation trials on
SRI.
Table 1. Average of yield contributing parameters
for 3 replicated SRI trials at three study sites
Objectives

• To evaluate and assess the different rice
  varieties grown (cultivars) in the country for
  their respective responsiveness to SRI practices
  as compared to conventional methods.
• üTo carry out and promote SRI experiments with
  different cultivars with the involvement of
  farmers and extension workers.

Methods
A total of three on-going location specific SRI
trials both on-farms (1600 1800 m) and
on-station (2000 masl) using a simple randomized
complete block design with 3 replications and
five treatments has been started in Kanglung Geog
(Fig.1). The treatments are planting spacing
(20x20 cm, 25x25 cm) and seedling age (three and
four leaf stage). The plot size is 5x4m2 and
there are a total of 15 plots in each site. Each
site is planted with a different variety of rice
Khangma map (Site I), Paropa (Site II) and Verna
(Site III), which are all local varieties.
Solarized bed was used to raise the nursery. Seed
was soaked in water for 48hrs before sowing. For
control plots, except for site I, 45-50 days old
seedlings were planted at site II and III. After
3 to 4 days of transplanting, control plots were
applied with pre-emergence herbicide (butachlor).
No compost was applied but a little quantity of
urea (4600) _at_ of 160gm per plot was applied at
about 50 days after transplantation due to
yellowing of the tip of leaves.
T-1 (Treatment 1 with 20x20 cm spacing and 3 leaf
seedling age for each site and so on.
Transplanted the seedling raised by farmers and
at the time of their transplantation.
The best performance of SRI was observed at site
I followed by Site II (Table 1). The reason can
be due to the soil type as sandy loam has been
found to be more suitable for SRI than clay soils
(BRAC report 2002). The constant monitoring
provided to the field can be another reason.
Among the three sites, site III was farthest and
frequent monitoring was difficult. Thus proper
intermittent irrigation and weeding, which are
necessary for SRI fields (Uphoff, 2005) failed
sometimes. Further, the young transplanted
seedlings at Site III were attacked by different
types of grasshopper that fed on the leaves first
and ultimately the stems.
In all the three sites, treatment with wider
spacing 25x25 cm and younger seedling 3 leaf
stage (P-2) have shown better yield
result(considering 1000 grains weighs 20 gm) with
a maximum yield of 17.2, 14 and 7.7 tons/hac in
site I, site II and site III respectively
(Fig.2). The contributing yield parameters such
as total number of fertile tillers, number of
filled grains per square meter and the height of
plant were more in treatment (P-2) as compared to
P-4 (similar spacing but older seedling) and
other treatments (P-1, P-3 control). This
indicates that maintaining wider spacing one
plant per hill and transplanting younger seedling
induces robust root growth, profuse tillering
(Fig.3), longer panicles and consequently more
grains per panicle (Fig.4) than smaller spacing
and transplanting older seedlings. The yield
performance of controls (traditional methods) in
all the sites were lower, which is in agreement
with the finding of Anthofer (2004) that SRI
method had better yield performance. However, the
yield is higher than the previously recorded
productivity of 3.66 tons/hac (MoA, 2004) in
Kanglung. This could be attributed to the
frequent monitoring received. 
Study site
Figure 1. Kanglung is one of the 16 sub districts
of Trashigang District and falls under mid and
high altitude rice growing zones. It has a
total of 588.50 acres under paddy cultivation and
the productivity is 408.28 MT (3.66 MT/ha)
which is higher than the national average yield.
Kanglung
Conclusion
The findings based on the contributing yield
parameters shows a positive trend towards the SRI
performance observed in many countries. With more
evaluations on SRI methods, it is expected that
the findings would enable marginal farmers in
Bhutan to enhance their rice productivity by many
folds. Farmers in some of the regions worst hit
by water scarcity
Acknowledgements
during paddy season would benefit the most by
this method as it require lesser amount of water.
The present trials have already sparked some
interest to the farmers as well as others. In
fact, farmers in Kanglung and other regions
already practices one of the aspects of SRI
i.e., transplanting of single seedlings but older
seedlings and in narrow spaces. So, I feel and
pray that it would not be difficult to help and
inspire farmers to learn and experiment on the
entire aspects of SRI.
I wish to acknowledge the help of Prof. Norman
Uphoff, CIIFAD, Rajendra Uprety, Biratnagar,
Nepal, Namgay Wangdi and his crew at the RNRRC
Khangma and many others for providing valuable
information for this work. I also thank my
student researchers and farmers for allowing
their plots to initiate such work. The financial
support received from TRAID foundation with the
initiatives of CIIFAD, Cornell University is
gratefully acknowledged.
Agricultural Statistics 2004. Ministry of
Agriculture, Royal Government of Bhutan, Thimphu.
http//www.moa.gov.bt/a_statistics.php Anthofer,
J. 2004. The Potential of the System of Rice
Intensification (SRI) for Poverty Reduction in
Cambodia. In International Agricultural Research
for Development. Berlin, October 5-7. BRAC
Centre 2002. Report of workshop on experiences
with The System of Rice Intensification (SRI) in
Bangladesh. Uphoff, N. 2005. Features of the
system of rice intensification (SRI) apart from
increasing yield.
References