Rice Genomics and Genetics 2015, Vol.6, No.3, 1-5
5
long-term fallow crops in suppressing weeds, weed
shift and improving soil fertility.
3 Materials and Methods
3.1 Study areas
The trial was conducted during the wet season in 2008
at Northern Agricul-ture and Forestry Research Center
(NAFReC) and at farmer’s field in Ban Silalek (SL),
Luang Prabang, Lao PDR.
3.2 Methods
The trial consisted of the following treatments:
(1) Rice only
(2) Rice + Line sown
stylosanthes
guinensis
(rice
Stylo
-L) (
stylosanthes
was sown in rows by 50 cm
apart within rice stand, four weeks after rice was
sown)
(3) Rice + Broadcast (rice
Stylo
-B) sown
stylosanthes
guinensis
The trial was laid out in a randomized complete block
design with three replicates in each site. Individual
plot size was 8 m x 10 m (80 m
2
). Laboun, a
traditional upland rice cultivar, was sown at a spacing
of 25 x 25 cm by placing about 8 seeds into 3-5 cm
deep holes made a dibble bamboo stick on late May
2008 at NAFReC and early June at farmer’s field, and
harvested on late September at NAFReC and Mid
October at Farmer’s field.
stylosanthes
seeds were
dipped in boiling water prior to seeding to break
dormancy and immediately seeded at four weeks after
rice sowing.
stylosanthes
was broadcasted into rice
crop at the rate of 4 g m
2
. Weeding practice and timing
was similar with those of farmers.
3.3 data collection
At rice tiller stage, panicle initiation (PI) and
harvesting time, rice and
stylosanthes
plant height and
plant number were measured from 15 random plants
per plot, while destructive plant biomass were
measured from a total 3 m
2
area by 3 random of each
1 m
2
samplings per plot. At maturity, panicle length,
spikelet fertility (SPF) and 1000 seed weight of rice
were measured from15 random plants per plot, rice
grain yield from a 3 m
2
area, while
stylosanthes
cover
was recorded in a 3 m
2
area in each plot.
Acknowledgements
Thank you to the financial support of Challenge Program on
Water and Food for the researcher provided through Rice
Landscape Management for Raising Water Productivity,
Conserving Resources, and Improving Livelihoods Basins is
also gratefully acknowledged.
Thank you to the Northern Agriculture and Forestry Research
Center for granting any facilitate for laid out of these trials.
References
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