1. R. Rajendran*, V. Ravi, N.Chelliah, and V. Balasubramanian
Individual and combined effect of management components of SRI on the productivity of irrigated rice
R. Rajendran*, V. Ravi, N.Chelliah, and
V. Balasubramanian
* Professor (Agronomy), Tamil Nadu Rice Research Institute (TNAU), Aduthurai, India

2. SRI Modified SRI Initiated from 2002 in Cauvery Delta, Tamil Nadu
Management practices tailored to the local conditions
Practiced in different names - countries/region
As “modified SRI” in Tamil Nadu
Initiated from 2002 in Cauvery Delta, Tamil Nadu

3. Practices recommended for SRI
Seedling age (days) 15
Seedlings per hill 1
Plant spacing (cm)
22.5 x 22.5
Planting geometry
Square
Mechanical weeding/ soil stirring
Two cono/rotary weeder
+ one HW (no herbicide)
Intermittent irrigation
2.5 cm up to flowering intermittently
Nutrient application
OM + fertilizers

4. Objectives To study the synergistic effect of SRI practices
To study the individual effect of SRI components on rice productivity
To study the synergistic effect of SRI practices
To assess the factor productivity in SRI

5. Experimental details Locations (2) : TRRI, Aduthurai, TN, India
SWMRI, Thanjavur, TN, India
Year :
Variety : ADT- R 45 (110 d )
Design : CRBD
Replication : 3
Treatments : 13

6. Treatment details YOSCI (SRI)
YOSCF
YOSHI
YORHI
YMSCI
AOSCI
AMRHI
YMRHI
AORHI
AOSHI
AMSCI
AMSHI
AMRHF (conventional)
Y - Young seedling (15 d ) A - Aged seedling (25 d) O - One seedling/hill M - Multiple seedlings hill-1 S - Square planting (22.5 x 22.5cm) R - Row planting (15x10 cm) C - Cono weeding H - Hand weeding I - Intermittent irrigation F - Flooding

7. Impact of inter-cultivation on yield, Cauvery Delta, Tamil Nadu, 2002-04
TRRI, Aduthurai
Yield enhanced by 29%
SWMRI, Thanjavur
Yield enhanced by 46%

8. Prob >F : F0, 0.07; LCCN, 0.02 and +K, 0.02
Impact of SRI +SSNM on irrigated rice productivity, Cauvery Delta, Kharif and rabi
Prob >F : F0, 0.07; LCCN, 0.02 and +K, 0.02
Rajendran et al., 2006

9. Dominating Pests
-- Leaf folder

10. Impact of SRI on pest incidence Conven-tional planting
Detail
No. of valid seasons
Conven-tional planting
SRI method of planting
Pest incidence
Whorl maggot (%LD) 5
11.56
4.82
Leaf folder (% LD) 8
12.97
21.04
Gall midge (% DT) 2
4.52
2.72
BPH (no./hill) 4
7.52
1.84
Stem borer (% DT) 6
9.86
5.48
Crop yield (kg/ha)
Grain yield
5,127
6,986
Ravi et al., 2006

11. SRI + SSNM on N use efficiency, Cauvery Delta, Kharif and Rabi, 2003-04
Prob > F : For LCC-N & + K, 0.02
Rajendran et al., 2006

12. Components of chlorophyll as influenced by SRI practices, Kharif, 2005*
Management / Variety
Chlorophyll
(a: b ratio)
ADT 43
ADT RH 1
Conv. + flooding
1.27:1
1.21:1
Conv. + intermittent irrigation
1.33:1
1.43:1
SRI + flooding
1.52:1
1.34:1
SRI + intermitt. irrig.
1.56:1
1.59:1
* Mean data

13. Root growth as influenced by SRI (inter-cultivation), Kharif, 2006*
Treatments
Root length (cm)
Root volume (cc)
ADT 43
PHB 71
Conv. + flooding
11.6
12.0
21.8
19.3
Conv. + inter. irrig.
15.2
15.1
23.3
26.3
SRI + flooding
16.3
16.1
37.7
39.2
SRI + inter. irrig.
16.5
51.0
57.7
CD (5%)
0.7
4.0
* On-going experiment

14. Nutrient uptake (kg/ha), TRRI Farm, Cauvery Delta, Kharif, 2005*
Treatment
Grain
Straw N P K
Conventional
57.0
7.9
8.7
32.6
5.9
68.7
SRI
74.1
11.0
11.3
43.7
7.8
87.0
C.D. (5%)
4.4
0.7
1.5
4.2
1.3
10.4
* On-going research project

15. Impact of older seedling age, Cauvery Delta, Tamil Nadu, 2002 -04
TRRI, Aduthurai
Yield reduced by 23%
SWMRI, Thanjavur
Yield reduced by 18%

16. * % yield increase over aged seedling
Seedling age on rice productivity and profit, Cauvery Delta, Tamil Nadu, Rabi,
Seedling age
Aduthurai
Thanjavur
Panicles/m2 GY
(kg/ha)
B:C
Traditional nursery – 25 days
377
5874
2.6
344
5557
1.9
Modified mat nursery
15 days
452
7061* (20)
3.2
424
6583* (16)
2.7
C.D (5%) 25
163
n. a 21
121
* % yield increase over aged seedling
Rajendran et al., 2005

17. Influence of seedling age when planted, based on leaf number, Cauvery Delta, Kharif 2006 & Kharif 2007 (in progress)

18. No. of leaves per seedling
Panicle production
No. of leaves per seedling
Panicles / sq. m
ADT 43
PHB 71
Seedling mean 2
391
404
398 3
438
456
447 4
397
423
410 5
350
402
376
Cultivar mean
403
425
C.D. (5%) 10 15

19. No. of leaves per seedling
Rice grain yield
No. of leaves per seedling
Grain yield (kg/ha)
ADT 43
PHB 71
Seedling mean 2
7595
7903
7749 3
9198
9457
9327 4
8016
8762
8889 5
7297
8299
7798
Cultivar mean
8277
8598
C.D. (5%)
145
230

20. Impact of flooding, Cauvery Delta, Tamil Nadu 2002 -04
TRRI, Aduthurai
Yield reduced by 17%
SWMRI, Thanjavur
Yield reduced by 16%

21. Synergistic effect of SRI on rice productivity, Cauvery Delta, Tamil Nadu, 2002 - 04
TRRI, Aduthurai
Yield enhanced by 51%
SWMRI, Thanjavur
Yield enhanced by 46%

22. Factor productivity for SRI and conventional rice cultivation, kharif and rabi, Cauvery Delta, Tamil Nadu,
Input use/cost
Aduthurai
Thanjavur
SRI
Conven.
Nursery cost efficiency
(Rs./kg grain)
0.21
0.66
0.62
Water use (m3)
8,964
14,193
11,952
15,687
Water use efficiency (kg grain m-3 water)
0.81
0.34
0.63
0.33

23. Factor productivity for SRI and conventional rice cultivation, kharif and rabi, , Cauvery Delta, Tamil Nadu
Input use/cost
Aduthurai
Thanjavur
SRI
Conven.
Fertilizer cost efficiency (Rs./kg grain)
0.64
1.01
0.62
0.93
Weeding cost efficiency (Rs./kg grain)
0.20
0.31
0.19
0.29

24. Targeted yield attributes for enhanced grain yield in SRI
Role of M SRI
1. No. of panicles/m2
2. No. of grains/panicle
3. No. of spikelets/panicle
Genotypic potential of rice plant tapped through:
Improved crop establishment
Soil stirring by cono-weeder
Intermittent irrigation
Synergistic effect of all
SRI components

25. Targeted yield attributes for enhanced grain yield in SRI
Role of Modified SRI
3. Increased no. of spikelets/panicle
Genotypic potential tapped through
Improved grain filling which resulted in more grain weight than with traditional planting

26. Improved grain quality in SRI
Treatments
Grain
length (mm)
width
(mm)
Kernel
length
Conventional
8.79
2.38
6.39
1.99
SRI
8.85
2.41
6.51
1.98
C.D. (5%)
0.09
0.04
0.08
Cauvery Delta, Kharif, 2005

27. For farmer-friendly and faster adoption of SRI:
What to do?
For farmer-friendly and faster adoption of SRI:
Strengthening of nursery & water management practices through community approach
Training of farmers and farm labourers in square planting
Mechanization of inter-cultivation
Increasing awareness on healthy nutrient management, especially for N management

28. Key is the healthy crop establishment

29. T h a n k y o u