Evaluation of the System of Rice Intensification in Bhutan Karma Lhendup Faculty of Agriculture College of Natural Resources Royal University of Bhutan Thimphu 2 nd National SRI Symposium, 2007

Brief background on paddy cultivation in Bhutan

Rice is cultivated in a wide range of elevations from 150 m - 2600 masl Over 50,000 acres -- about 20,235 hectares -- are under rice cultivation in Bhutan (MoA, 2004)

Average rice productivity is about 2.88 ton/ha

SRI in Bhutan No documentation of any SRI activities in Bhutan prior to 2006

No documentation of any SRI activities in Bhutan prior to 2006

In 2006, SRI evaluation trials were carried out at three locations in Eastern Bhutan.

Objective To assess the respective responses to SRI practices of different rice varieties (cultivars) popularly grown in Bhutan. To disseminate and promote SRI technique to community and agriculture extension workers. To seek greater knowledge about SRI under Bhutanese conditions

To assess the respective responses to SRI practices of different rice varieties (cultivars) popularly grown in Bhutan.

To disseminate and promote SRI technique to community and agriculture extension workers.

To seek greater knowledge about SRI under Bhutanese conditions

Kanglung Geog Kanglung is one of the 16 Geogs (blocks) of Trashigang district Methodology: Location of study sites Site I (Khangma) Site II (Thragom) Site III (Pangthang)

Kanglung is one of the

16 Geogs (blocks) of

Trashigang district

Site I Site II Site III Site Characteristics Site Altitude (masl) Texture Variety planted pH (H 2 O) I (Khangma) 2000 Loam Khangma maap 4.4 II (Thragom) 1850 Loamy to sandy clay Paropa 4.47 III (Pangthang) 1600 Sandy loam to sandy clay loam Verna 5.99

Experimental Design RCBD with 3 replications and 5 treatments Treatments were: 20 x 20 cm spacing, 3-leaf stage seedling age 20 x 20 cm spacing, 4-leaf stage seedling age 30 x 30 cm spacing, 3-leaf stage seedling age 30 x 30 cm spacing, 4-leaf stage seedling age Control (farmers’ practice), > 7 leaf stage Plot size was 5 x 4 m2, with a total of 15 plots at each site

RCBD with 3 replications and 5 treatments

Application Granular pre-emergence herbicide Butachlor was applied @ 40 grams per 10 m 2 containing 5 % Butachlor. Urea was applied at the rate of 173.8 gm per plot, equivalent to 40 kg/ha, at 55 days after transplantation due to yellowing of the tips of leaves.

Granular pre-emergence herbicide Butachlor was applied @ 40 grams per 10 m 2 containing 5 % Butachlor.

Urea was applied at the rate of 173.8 gm per plot, equivalent to 40 kg/ha, at 55 days after transplantation due to yellowing of the tips of leaves.

Note The full set of SRI’s recommended practices was not assessed – only: (a) Seedling age (younger vs. older) (b) Wider spacing -- plant density per hill and per square meter (m 2 ), and (c) Water control – reduced amounts

The full set of SRI’s recommended practices was not assessed – only:

(a) Seedling age (younger vs. older)

(b) Wider spacing -- plant density per hill and per square meter (m 2 ), and

(c) Water control – reduced amounts

(d) Weeding (active soil aeration) through the use of a rotary weeder was not done; a hand hoe was used to loosen the soil. (e) Additional organic fertilization was not applied, although cattle were tethered in the fields for about 2-3 weeks prior to ploughing the field. The results reported here are thus for partial application of SRI methodology.

(d) Weeding (active soil aeration) through the use of a rotary weeder was not done; a hand hoe was used to loosen the soil.

(e) Additional organic fertilization was not applied, although cattle were tethered in the fields for about 2-3 weeks prior to ploughing the field.

The results reported here are thus for partial application of SRI methodology.

Results and Discussion 3-leaf stage seedlings spaced at 30 x 30 cm gave the best results for all measurements Yield-contributing parameters were higher in SRI plots than with conventional methods

3-leaf stage seedlings spaced at 30 x 30 cm gave the best results for all measurements

Yield-contributing parameters were higher in SRI plots than with conventional methods

Results and Discussion In all three sites, SRI plots on average showed better yield performance as compared to conventional method . Yield at three different sites calculated at 14% moisture content Sl.No Parameters Site I Site II Site III 1 Rice variety Khangma maap Paropa Verna 2 2.1 2.2 2.3 2.4 2.5 Yield (kg/plot/Mt/ha) 20x20 3-leaf stage 20x20 4-leaf stage 30x30 3-leaf stage 30x30 4-leaf stage Control (3.90) 5.7 (3.47) 5.2 (4.03) 6.0 (3.53) 5.3 (3.50) 5.2 (2.63) 3.9 (2.57) 3.8 (2.83) 4.2 (2.53) 3.8 (2.45) 3.6 (2.57) 3.8 (2.20) 3.3 (2.83) 4.2 (2.43) 3.6 (2.45) 3.6

In all three sites, SRI plots on average showed better yield performance as compared to conventional method .

a cv = 9.5% b ** = Significant at 1% level of significance Analysis of variance (RCB) for grain yield data Sources of variation Degrees of freedom Sum of squares Mean squares Computed F b Tabular F 5% 1% Replication 8 35.05 4.38 4.54** 2.67 3.97 Treatment 4 3.11 0.78 Experimental error 32 5.48 0.17 Total 44 43.64 5.33

Dissemination of SRI techniques

Conclusion Trials have already sparked some interest among farmers as well as researchers and extension workers. Moreover, this study would contribute to the promotion of organic farming in Bhutan. Evaluations of SRI methods at various elevations in Bhutan are continuing. SRI Plot Sharing SRI technique to agriculture students for multiplier effect.

Trials have already sparked some interest among farmers as well as researchers and extension workers.

Moreover, this study would contribute to the promotion of organic farming in Bhutan.

Evaluations of SRI methods at various elevations in Bhutan are continuing.