3. Intercultivation
• Better crop establishment, vigorous growth upto
the time of maturity.
• good soil aeration and better development of root
systems.
• necessary to help control the growth of weeds
• moisture-conservation measure by closing cracks in
the soil.
• active soil aeration is a function usually overlooked
when intercultivation is referred to as 'weeding.'
4. Intercultivation in Rice
• In contemporary rice culture,
intercultivation is not considered as a
very important agronomic practice.
• However, it has been practiced to some
extent in the past, primarily as a weed
control measure.
5. Mechanical weeding
• rotary weeder was apparently first developed
by a Japanese farmer in 1892.
• requires row-planted crops
• very difficult if the soil surface is dry, or if the
soil sets hard. If the soil is too dry, the weeder
rolls over the soil surface without burying the
weeds
• inability of rotary weeding to remove weeds
within or close to rice hills
6. History
• Stirring the soil once in a fortnight until
the rice plants are about 1-½ feet height
emphasized (Mukerji, 1907)
• advocated shallow digging of the inter-
row spaces with a spade 20 days after
transplanting, and again at 40-45 days
after transplanting (Vaidyalingam Pillai,
1911).
7. Stable and high-yielding rice cultivation
• inter-tillage after the roots of the
transplanted seedlings are reestablished
• removing the soil around the base of
the plant hill by hand, to make the hill
spread out and promote tillering
(Matsushima, 1980)
8. • depressed the growth of rice temporarily,
but after 1-2 weeks the growth became
more vigorous
• no significant difference in yield
• some negative effects on growth and yield
under adverse environmental conditions
such as low air temperature and insufficient
sunshine
Effect of Intercultivation
(Seko and Kuki, 1956)
9. • the roots of the rice plants in the shallow part of
the soil were cut or stirred; when new roots grow,
the number of total roots and weight became
greater than in non-cultivated soil; further, those
roots which had been cut elongated rapidly;
• redox potential was high after intercultivation, but
it became lower than non-cultivated soil after 3-4
days; and
• NH4-N content of the soil increased due to mixing
up of the oxidized uppermost layer into the
reduced lower layer.
Effect of Intercultivation
(Seko and Kuki, 1956)
10. Intercultivation :
Theories believed since the 17th century (Nojima, 1960)
• physico-chemical change - decomposition of
organic matter - increases the supply of nutrients
• Decrease of amount of toxic gases – increase in
the amount of useful oxygen
• Cutting of roots promotes the growth rate of
plants; and
• cumulative effect - final yield is increased to a
great extent.
11. Recommended weed control methods
Tamil Nadu
• Hand weeding twice, at 15 and 35 DAT, or use of a
herbicide at 3-7 DAT, plus one hand weeding at 35 DAT
Handbook of Agriculture, ICAR (2010)
• Hand weeding 2-3 times at 20-day intervals from 20
DAT. If weed problem is acute, herbicide plus need-
based hand weeding 20 days later.
IRRI Rice Fact Sheet (2003)
• Hand weeding at 20-22 and 30-32 DAT, repeated once
or twice more at 40-42 and 50-52 DAT; or Mechanical
control with rotary hoe at 10-12 or 20-22 DAT, and
repeat its use once or twice at 30-32 and 40-42 DAT.
12. • Intercultivation with a weeder at 10-day
intervals, from 10-12 days after planting until
the canopy closes, upto 4 times (10-12 DAT, 20-
22 DAT, 30-32 DAT, 40-42 DAT).
• Cultivate between the hills in two directions,
perpendicularly, and remove the remaining
weeds close to the plants, if any, by hand.
Weed Control in SRI
16. Cost of weeding and inercultivation
Method of weeding
Type of
labour
Wages
/labour
day)
Labourer
requirement
/acre
Cost of
weeding
(Rs/acre)
Rice Research Station, Tirur, Tamil Nadu, 1958
(Venkatasubramanian, 1958)
Conventional random planting (hand
weeding twice)
Women
56
naya
paise
14 7.84
Line-planted (rotary weeder three times) Men
87
naya
paise
6 5.22
Farmer’s field, Tirunelveli, Tamil Nadu, 2003
(Thiyagarajan et al. 2005)
Conventional random planting (hand
weeding twice)
Women Rs.40 32 1,280
SRI –square-planted (conoweeder 4
times plus hand weeding of left-out
weeds)
Men Rs.40 15 600
17. Cost of weeding and inercultivation
Method of weeding
Type of
labour
Wages
/labour
day)
Labourer
requirement
/acre
Cost of
weeding
(Rs/acre)
Regional Research Station, Paiyur, Tamil Nadu, 2005-2008 (six-season average)
(Vijayabhaskaran and Mani, 2008)
Conventional random planting (herbicide
followed by hand weeding once at 45
DAT)
Men and
women
Rs. 92 15 1,380
Square-planted (conoweeder three
times, plus hand weeding of left-out
weeds)
Men and
women
Rs.92 10 920
V.K.V. Ravichandran, Farmer, Nannilam Tamil Nadu, 2009
(personal communication)
Conventional random planting (hand
weeding thrice)
Women Rs.80 30 2,400
SRI- square-planting (conoweeder three
times, plus hand weeding of left-out
weeds)
Men
Women
Rs.150
Rs.80
9
6
1,350
480
18. SRI farmers had a 43 % reduction in
their overall labour costs
(Ravindra and Bhagya Laxmi, 2011).
19. Labour and Intercultivation
• If a single labourer does the operation on one
hectare of SRI crop with 25 x 25 cm spacing, he
will have to walk 40 km to use the weeder in
one direction, and 80 km in both directions.
• a lot of variations in the acceptance in using the
weeder
• completely eliminating women labourers for
hand weeding
• On average, the number of labourers required to
cover an acre in both directions may vary from 3
to 5
20. Labour and Intercultivation
• In labour-scarce areas, higher wages may be
demanded
• Groups of labourers often join together and go
for contract weeding operations
• Most marginal farmers do their SRI weeding
operation entirely by family labour, completely
eliminating their weeding cost
• Instances of a farmer doing the weeding
operation all by himself
21. Reducing the drudgery in Intercultivation
• Modifying the weeder design with ball bearings
to reduce friction
• Having a set of (say, 10) trained labourers for
doing weeding in a village and employing them
by contract
• Instead of using the weeder in both directions at
10-day intervals, use it in one direction the first
time, and then in the opposite direction after
seven days, and repeat this
• Use of a motorized weeder
22. Considerations in Intercultivation
• First use of the weeder at 10-12 days after
transplanting is crucial in SRI and should not be missed
• Herbicides are not recommended
• Some water should be there on the field while using
the weeder
• It is important to remove left-out weeds by handIf a
weeder is used after a top dressing of urea, this will
incorporate the fertilizer and increase its use-efficiency
• The suitability of different types of weeder is site-
specific and depends upon soil conditions and
labourers’ mindset
28. Effect of Intercultivation
Treatment Grain yield
(kg/ha)
Weeding
cost
(Rs/ha)
Cost of production
(Rs/kg grain)
EXPT1 EXPT2 EXPT1 EXPT2
HW 5655 5550 3960 5.04 5.14
HW + IC 6480 7249 5112 4.58 4.09
HW : Hand weeding at 15 and 30 DAT
IC : Intercultivation with weeder AFTER hand weeding
Ramamoorthy (2004)
29. • Data collected from 76 farmers using SRI
methods in Madagascar in the 1997- 1998
season showed that each weeding beyond two
added 1 to 2.5 t ha-1 to yield (Uphoff, 2002).
• In Nepal, data from 412 farmers showed that
farmers who used the weeder three times got
yields of 7.87 t ha-1, 2 t ha-1 higher than the
majority of farmers who weeded only twice
(5.87 t ha-1). Farmers who weeded only once
lowered their yield (5.16 t ha-1) by 600 kg ha-1
compared to those who did two weeding
Effect of Intercultivation
30. Seedling
age
(days)
No. of
seedlings
per hill
Weeding
practice
Irrigation
practice
Grain yield
(kg ha-1)
Increase over
conventional
(%)
Increase
over full
SRI use
(%)
15 1 Intercultivation Intermittent 7,061 (+) 48.8 -
25 1 Intercultivation Intermittent 5,864 (+ 23.6 (-) 17.0
15 3 – 4 Intercultivation Intermittent 6,138 (+) 29.4 (-) 13.1
15 1 Hand weeding Intermittent 5,698 (+) 20.1 (-) 19.0
15 1 Intercultivation Flooding 6,425 (+) 35.4 (-) 9.0
25 3 – 4 Hand weeding Flooding 4,745 - (-) 34.2
Effect of Intercultivation
Rajendran et al, 2005
31. • Intercultivation with mechanical weeders in SRI not only
plays a role in the control of weeds but also has been
found to have a beneficial effect on the growth of the
crop.
• With appropriate models and skills, farmers can greatly
reduce their cost of weeding also.
• Some of the constraints in using the weeder are associated
with availability of weeders for which some policy support
from extension agencies is needed.
• The labour mindset which is often negative can be sorted
out through education and training.
• More to be understood on the effect.
Conclusions
32. V. Geethalakshami
Professor and Head
Agro Climate Research Centre
Tamil Nadu Agricultural University
Coimbatore, TN, India
geetha@tnau.ac.in
Sustaining Rice Production under changing
Climate : A case Study in Cauvery Basin
33. Presentation Outline
• Introduction
• ClimaRice- An Integrated approach
• Observed Climatic trends and future climatic projections
• Impacts – Water / Rice Productivity / GHG emission
• Adaptation and Mitigation options
• Way Forward
• Take Home Message
34. Introduction
There is compelling evidence that climate change is not only an
environmental issue but also a serious sustainable development
challenge
Climate change impacts will affect all countries - Developing countries and
the poor will bear disproportionately high negative impacts
Challenges :
Uncertainty Issues
Integration of different disciplines
making the knowledge accessible to the most vulnerable group
Long term planning
“Energy security and climate change are two of the great challenges of our time.
These challenges share a common solution: technology.”
George W. Bush in Major Economies Meeting on September 28, 2007
35. Graphical User Interface
DATABASE
Derived Surface Water For
Irrigated Agriculture
EPIC
INPUT
MODELING
OUTPUT
SWAT
INPUT
MODELING
OUTPUT
Front end procedures
Back end procedures
Graphical User Interface
DATABASE
Derived Surface Water For
Irrigated Agriculture
EPIC
INPUT
MODELING
OUTPUT
EPIC
INPUT
MODELING
OUTPUT
SWAT
INPUT
MODELING
OUTPUT
SWAT
INPUT
MODELING
OUTPUT
Front end procedures
Back end procedures
My SQL
Climate Models
Climate, Histories, GCMs/RCMs, Downscaling
Management options
Input
Yield
Input
Alternate technology
Mitigation measures
+
Socio Economic
Analysis
Stake holders workshop
Field survey
Economic assessment
Technical briefs, Policy briefs, Scientific articles, reports
Economic cost of
climate change
Climate change and persistent Droughts: Impacts,
Vulnerability and adaptation strategies for rice
growing sub-basins of India
36. CLIMARICE – AN INTEGRATED
APPROACH
• Assessing the climatic trends and developing future climate
projections
• Studying the complex interaction and impacts of climate
variability / change in hydrology and Rice productivity
• Developing a tool box (models, indicators, measures for
adaptation) for developing Adaptation Options
• Quantification of Green House gas Emission from paddy field
ecosystem
• Developing GHG mitigation options using microbes and agro
techniques
• Emphasizing on Stakeholder involvement and Capacity building
• Developing guidelines for policy makers and development
agencies
37. Observed trends : Temperature Time Series of India
Source: Data from India Meteorological Department
2006 (+0.595)
2002 (+0.59)
2007 (+0.55)
1998 (+0.50)
2004 (+0.47)
2001 (+0.47)
2003 (+0.45)
1958 (+0.43)
1987 (+0.41)
1941 (+0.41)
2005 (+0.40)
1999 (+0.39)
1953 (+0.36)
2000 (+0.36)
1980 (+0.34)
38. India: Decrease in Rainy days
but increase in Heavy Rain events
Decrease in rainy days and
increased dry spells
More intense rainfall
More Flash FloodsBUT
40. Sea Level Rise- Observations
Sea-levels increase by ~ 1.3 mm/year
Unnikrishnana et al. Curr. Sci, 90, 365-372, 2006
• Area: 115 square miles
• Population: 143,000
• Highest point: 20 ft
above sea level
Climate Change induced
Sea Level Rise may
inundate some of the
islands of Maldives
The Maldives
Bangladesh is projected to lose
about 16% of its land area with a
sea level rise of 1.5 m
by end of this century
BangladeshIndia
44. El Niño impact on rice production, Philippines
5000
6000
7000
8000
9000
10000
11000
12000
13000
82 84 86 88 90 92 94 96 98
Year
PalayProduction(x1000MT)
El
Nino
El
Nino
El
Nino
El
Nino
45. Climate Modeling
Climate Data from IPRC
IPRC Regional Climate Model
Simulations
• Model : IPRC_RegCM
• Resolution : 25 Km
• Simulation : Current & future
climates
• Boundary conditions :
ECMWF
• Outputs : for Crop /
Hydrological models
Climate Data from TNAU
Model : PRECIS 1.7
Region : Tamil Nadu
Resolution : 0.22o x 0.22o or 25 x 25 km
Scenario : IPCC SRES A1B
Diagnostics : Hourly & daily surface and
upper air data +climate means
Period : 1961 – 2099
Run length : 139 years completed
RegCM3
4.90 to 28.20 N & 71.30 to 94.00 E
0.22o x 0.22o or 25 x 25 km
IPCC SRES A1B
Hourly & daily surface and upper air
data +climate means
1970 – 2100
131 years completed
Source: Rajalakshmi (2010)
Source: Annamalai, IPRC, Hawaii (2010)
50. Digital Elevation Map of
Cauvery Basin
Delineation of Watershed
and Sub-basins
No. Of Sub basins : 301
Hydrological Response Units
No. of HRUs : 3600
51. Hydrological components of Cauvery Basin -
SWAT output
Particulars Amount in
mm
Rainfall
(Observed)
1128.67
Surface flow 188.90
Lateral Flow 15.57
Ground
water
152.14
Percolation 212.64
Soil water 786.12
ET 704.62
PET 2195.73
Rainfall, ET and PET
0
50
100
150
200
250
Jan
Feb
M
ar
Apr
M
ay
Jun
Jul
Aug
Sep
O
ct
N
ov
D
ec
mm
Rainfall ET PET
53. Increase in CO2 + Increase in Temperature + Monsoon variation
Increasing glacier melt - Change in availability of irrigation water
Change in crop water requirement
Fertilizer Use Efficiency
Green House Gas emission
Latitudinal and Altitudinal effect
Population dynamics of pest and disease
Impact due to extreme weather events
Quality of Agricultural Produces
Consequences of increase in Sea level
Possible effect of Climate Change on Rice
54. Change in yield (%)
Effect of + 2 ºC on rice production
Major rice growing areas of the world
55. ET PET
0 0C 938 828
1 0C 939 1829
2 0C 977 1932
3 0C 994 1986
4 0C 1007 2040
5 0C 1027 2095
Parameters
in mm
Increase in temperature
0°C 1°C 2°C 3°C 4°C 5°C
Surface Q 143 143 138 134 138 136
Gr-Water Q 143 143 136 134 132 129
Percolation 202 202 193 189 188 184
Soil Water 2035 2034 1978 1950 1927 1904
Water yield 284 284 274 270 267 264
Sensitivity analysis for the
increase in Temperature
Rainfall : 871 mm
Kharif Rabi
0 0C 4762 4216
1 0C 4761 4262
2 0C 4465 5111
3 0C 4186 5038
4 0C 3909 4793
5 0C 3651 4503
57. Sources of greenhouse gas
emissions in India
Industrial
processes
8%
Wastes
2%
Land use
changes
1%
Agriculture
28%
Energy
61%
Source: India’s Initial National Communication on Climate Change, 2004
Fossil fuel used in agriculture
considered in energy sector
Rice cultivation
23%
Manure
management
5%
Emission from
soils
12%
Enteric
fermentation
59%
Crop residues
1%
Contribution from sectors
of agriculture
58. Methane emissions from rice is much smaller
than estimated by western agencies
0
10
20
30
40
1990 1995 1998 2004 2004 2006
Year
Methaneemission,Tg/year
EPA
IPCC
MITRA MOEF IARI IARI
59. Redox and DO variation in paddy eco system
0
1
2
3
4
5
6
7
8
DO(ppm)
T1 T2 T3 T4
Treatments
Fig.1 Influence of algae and azolla on Dissolved oxygen
(ppm) content of rice field under conventional system
(Reading taken at the stage of flowering)
First Day Second Day
Third Day Fourth Day
Fifth Day
61. Screening temperature tolerant rice cultivars
Growing of rice under growth chamber with modified temperature
1. Control
2. Growth chamber without net (4-6 OC)
3. Growth chamber with net (1.5-2 0C)
Screening of high temperature
tolerant rice cultivars
1. ADT - 36
2. ADT – 37
3. ADT - 38
4. ADT - 39
5. ADT – 43
6. CO 43
7. CO 48
8. Zeeraga samba
9. White ponni
10. CR 1009
11. CORH -3
62. Shifting of sowing window
932.5
928.2
945.1
4484
5506
4216
Advanced
Normal
Delayed
ET Yield
Early Sowing
Normal Sowing
Late Sowing
63. Changing the system of cultivation
Rainfall : 871 mm ET : 709 mm PET : 1828 mm
Flooded SRI
Area under Rice crop in ha
(56 % of 3246.4 sq.km) 1817984 1817984
Total water required for irrigation under flooded
cultivation (mm)
2217940480 1672545280
Total water saved in the basin (mm) - 545395200
Additional area that can be brought to Rice (ha) 447045 592821
Yield (Kg/ha) 3032 4109
Yield advantage - 26%
21 Number of Irrigations given 28
1220 Quantum of water used 920
- 0 - Saving of irrigation water 300
64. Altering Water Management
Particulars
Aerobic Rice
Alternate wetting
and Drying
Rainfall (mm) 871 871
ET (mm) 692.8 704.5
PET (mm) 1828 1828
Number of Irrigations given 19 17
Total Quantum of water used
for irrigation (mm) 740 1020
Saving in irrigation water / ha 280 -
Yield 2401 3282
Yield advantage - 1831
65. GHG mitigation technologies (MTech)
There could be about 20 potential MTechs:
They differ in terms of
Water regime
Residue management
Soil management
Fertilizer additives
Cultivar
Pathak and Wassmann (2007)
66. Methane
‘Generic’ mitigation options for GHG
emission from agricultural soils
Modification of irrigation pattern
Management of organic inputs
Change of crop establishment technique
Change of fertilizer management
Use of suitable crop cultivars
67. More methane
Mitigation of methane emission
Less methane
Aerobic rice
Bed-planted rice
Less methane
Direct seeded rice
68. Nitrous oxide
‘Generic’ mitigation options for GHG
emission from agricultural soils
Improving N fertilizer management
Optimizing irrigation practices
Optimizing tillage operations
Managing organic inputs
71. CLIMA RICE AND STAKEHOLDERS
Stake holder’s Panel
- Farmers
- Farmers Association
- Joint Director of
Agriculture
- Water resource
organization
- Krishi Vigyan Kendra
- Public Works
Department
Focus Group
Meeting
Scenario Development Meeting
Stakeholders Workshop
Capacity Building Trainings
On farm Research
Clima village- Thirumangalam
72. Way forward….
Climate Smart Farming
Case of Cyclone Thane: major
impacts include
58,000 ha of paddy (ready
to be harvested) affected
Cashew plantations and
other crops destroyed
Inland fisheries and
livestock destroyed
Industrial units (eg:
sugar factory) & stocks
damaged
Community based climate risk management programes
73. Farmer’s decision???
To plant Cotton or Sorghum ???
How many ac of cotton ???
Land configuration decision ???
What variety to Chose ???
What planting density to adopt ???
Case Study
Farmer : Mr. Palanisamy
Village : Arasur
Year : 2004
Decision : Banana against
seasonal crops
Benefit : Rs. 1.25 lakhs from
one ha of land
74. Weather based Agro Advisory
(1 x 9 x 10 x 3 = 270)
PaddyCrop
(1)
Weather
Scenarios
(10 – 15)
Agro
Advisories
(3-4)
Stage of
Crop (9)
N TP T FPI GF PHM H
H.Rain
High RH
Low T
Dry Spell
High T
Low RH
3 4 5 6 7
Post pone irrigation, Create drainage
Postpone PP against sucking pest
Chance for blast incidence
76. PLAN FOR CROP YIELD FORECAST
INITIAL MID-TERM PRE-FINAL FINAL
SOWING VEGETATIVE FLOWERING PRE
HARVEST HARVEST
HISTORICAL
METHOD (20
data)
LAND OBSERVATION
&
WEATHER DATA
RS - NDVI , LAI,
ACRE,
WEATHER DATA,
LAND
OBSERVATION
RS - NDVI , LAI,
ACRE,
WEATHER DATA,
LAND
OBSERVATION
77. Take Home Points
There is a strong evidence that the climate is changing.
Agriculture is one of the key sectors expected to be impacted.
Rice growing eco-system also potentially contributes to GHG
emission.
Climate resilient agriculture with eco friendly technologies with the
community participation would pay way for sustainable agriculture.
Adaptation projects and programs could be evolved and
implemented by adapting Climate Risk Management frameworks.
.
78. Those least able to cope and least
responsible for Global Warming
are the most affected
Mahatma Gandhi said that “There are people
in the world so hungry, that God cannot
appear to them except in the form of bread”
79. Theodore Roosevelt, America’s 26th
President and a dedicated conservationist,
said:
"The nation behaves well if it treats the
natural resources as assets which it must
turn over to the next generation increased,
and not impaired in value."
The science that we do, we research, allows
us to clean our air, improve our health, and
leave our planet a better place for our
children.
80.
81. SVK Jagadish*, R Muthurajan, T Ishimaru, S Heuer, PQ Craufurd
*International Rice Research Institute
Philippines
Strategies to address heat and drought
tolerance at flowering in rice
83. Wassmann et al., 2009
Potential effects of elevated CO2 and
high temperatures on rice
84. Why we do what we do……
Location Year Stress Damage
China 2003 Heat stress at
flowering
3 M Ha (5.2 Mt of
paddy)
Japan 2007 >40oC at flowering >25% yield loss
Pakistan 2007 Heat stress at
flowering
30% yield loss in
variety IR6 & 70% in
hybrids
India 2002 Drought 300 million people
affected
SE Asia 2004 Drought 2 M ha (8 M people)
Africa Recurring Drought 20 M ha of rainfed
lowland
87. IR64
N22
Seven genotypes – 7.1 to 11.4cm grain length
Distance between flag leaf collar and the fully opened leaf
Morphological marker for
microsporogenesis identified
4mm 5mm 6mm 7mm
88. Genetic diversity for heat tolerance
at microsporogenesis exists
0
20
40
60
80
100
120
CG
14
DR
29
IR
6
IR64
IR2006
N22(4819)
Vandana
Genotypes
Spikeletfertility(%)
Control
Heat
Negative impact on microsporogenesis?
Is it just the micro or the mega gametogenesis also leads to
sterility under heat and drought stress?
89. Physiology of heat (drought?) tolerance
Muthurajan et al., 2012
Moroberekan heat stress
N22 heat stress
Drought stress
Pollentubetoreachmicropyle(h)
Liu et al., 2006
IR64 Moroberekan
94. 30o
C 35o
C 38o
C
Azucena S 66.1 23.4 02.9
Bala T 89.8 81.4 40.6
CG 14 MT 89.6 71.7 19.1
Co 39 T 86.1 83.5 40.5
IR 64 MT 93.2 68.3 18.7
Moroberekan S 83.3 39.9 06.4
N22 HT 95.6 91.3 63.7
WAB 56-104 S 94.6 76.0 19.2
Jagadish et al., 2008, Crop Sci., 48:1140–1146
N22 a true high temperature tolerant donor
N22 two most tolerant accessions identified
N22 tolerant at microsporogenesis stage
N22 most tolerant to high night temperature under field (Peng et
al., UnPub) and under controlled environments (Coast et al., UnPub)
95. qtl1.1
Chromosome 1
SSPf4
Chromosome 4
QTLs/proteins for heat tolerance at anthesis
Jagadish et al 2010 – Bala x Azucena
Xiao et al 2010 – 996 × 4628 HSP 1 HSP 2
Control
Heat stress
Pollinated stigma
HSP 1
HSP 2
Spikelet protein expression
Control Heat stress
97. Nipponbare …CAGAAAGCGAAAGATAGAGCAA…
N22 …CAGAAAGCGAAAGTTAGAGCAA…
Nipponbare …CATGCGGCGGTTCAGGCTGCCGGAG…
N22 …CATGCGGCGGTTCCGGCTGCCGGAG…
Allelic sequencing
Promoter sequence analysis
Functional validation - transformation
Molecular Markers for developing heat tolerant
rice by MABC
E.g. Heat shock protein
98. Impact of local climatic
conditions on rice spikelet
fertility and grain quality in hot
and vulnerable regions of India
JIRCAS President Incentive
Project
Developing mega-varieties
with Early-Morning Flowering
(EMF) rice to mitigate high
temperature-induced sterility
at anthesis GRiSP New
Frontier
Mapping populations
developed and QTLs for
heat tolerance at flowering
identified, fine mapped and
validated through NILs
CSISA
Field survey for heat-
induced sterility in India
Development of Early-morning
Flowering near isogenic line for
climate change adaptation
Climate Change Adaptation
for Rice Rainfed Area
(CCARA)
Provide donor line
for EMF trait
Development of heat ‘escape’ lines Development of heat ‘tolerance’ lines
Pyramiding heat escape and
tolerance – apart of the BMZ
funded project on Safeguarding
Asian rice production from a
rapidly warming climate
Combining heat escape and tolerance
99. Field phenotyping at hot spots in South Asia (CSISA)
What it will include?
Weather stations on the site
Canopy temperature/RH recorders
Infrared thermometers – leaf T
Material planned for testing
150 wide hybridization lines
(Dr Subramanian)
150 salinity tolerant lines
40 heat tolerant donors
250-300 Indica/aus for association
mapping
Additional drought lines
Exploring novel source of heat escape,
avoidance, tolerance
Bharwale Foundation
(Dr Ramesha)
TNAU
(Dr Raveendran)
PAU
(Drs Mangat and Kaur)
Jessore,
Bangladesh
102. Mapping heat and drought occurring
regions of South and SE Asia
Bangladesh, eastern India, southern Myanmar, and northern Thailand
Jagadish et al., FPB, 2011, 38, 261–269
103. Rice
Tissue temperature under water-limited
conditions
Garrity and O’Toole, 1995
29 31 33 35 37 39
Canopy temperature [oC]
200
160
120
80
40
0
Grainyield(g/m2)
Leaf temperature [oC]
Cotton
Cohen et al., 2005
104. Rang et al., 2011
N22 a combined high temperature and
drought tolerant donor
80
60
40
20
0
Spikeletfertility(%)
100
C HT WS HT+WS
105. Physiological processes under
heat and drought stress
C – Control WS – Water deficit stress
HT – Heat stress HT+WS – Heat and water deficit stress
(Heat and drought tolerant)
(Heat and drought susceptible)
108. Summary and ongoing activities
Reports on high temperature leading to yield losses
are on the rise
NILs with EMF in indica background developed
NILs (QTL and candidate genes) for heat tolerance
being developed
Hot spots to explore sources for heat escape,
avoidance and tolerance established in 2012
Options for combining heat and drought tolerance
Combine heat escape + tolerance (and drought) and
field testing and dissecting the mechanisms
High night temperatures – a completely different
story
Maintenance respiration, assimilate partitioning,
grain filling, grain quality
Transcriptomics and metabolomics of floral organs
for heat and drought stress under progress
110. Increasing temperature and water
saving technologies
Flooded paddy Safe AWD
Munns et al., 2010
Aerobic and direct seeded
111. Apoplasmic assimilates: an indicator
for filling capacity of rice grain
Dr P K Mohapatra PhD (Adelaide)
CSIR Emeritus scientist
School of Life Science
Sambalpur University
Jyoti vihar, Sambalpur 768019
112. Rice originated in unstable environment
(Drought and Flooding)
Survival strategy
Production of excess reproductive
structures
Formation of excess Production of large
numbers of spikelets numbers of tillers
Environmental Factors Determine sustenance of reproductive structures
113. Chang hypothesis 1976
(Cook and Evans, 1983)
COMMON ANCESTOR
South and South East Asia Tropical Africa
Wild perennial
Wild annual
Weedy annual
Cultivated annual
O.rufipogon
O.nivara
O.spontanea
O.sativa
indica japonica javanica
O.longistaminata
O.berthi
O.staptu
O.glaberrima
Plasticity for adaptation is very high in the wild species
119. Heterogeneous architecture leading to inter-grain
apical dominance in spikelet development is an
important strategy for survival and completion of
life cycle of the plant under uncertain conditions.
When inclement weather coincides with the sensitive
stage of spikelet development, the plant sacrifices
some spikelets while preserving the rest to provide
seeds for the next generation.
120. Heterogeneous panicle architecture:
a liability
• Each spikelet is genetically competent to bear
a grain at maturity.
• Interaction between environment and
genotype determines grain number.
• Spikelets lost during development underscores
genetic potential of the cultivar.
• Intrinsic physiological factors limit grain
number under stress free situation.
121. Physiology of yield potential
• Physiological basis for genetic yield potential has
attracted attention of crop physiologist since
introduction of green revolution in rice (Chandler,
1969) and award of Nobel peace prize to Norman
Borlaug in 1970.
• Crop physiology research represented the state of art
for cellular, leaf level and whole plant physiology. It
involved research on crop yields based on
improvements in physiological characteristics (Evans,
1993). Manipulation of intrinsic and extrinsic factors
including stress physiology was also considered.
122. Yield barrier
• In the last 3-4 decades, thousands of semi-dwarfs
were produced world wide increasing national yield
averages because of advantages over the early semi-
dwarfs in traits like maturity period, milling quality
and resistance to biotic and abiotic stresses.
• The improved semi-dwarfs could not surpass yield
potential of IR8, Jaya or Bg-90-2.
• Yield capacity of rice stagnated.
• Improved yield would not come from continued
crossing and selection within semi-dwarfs.
123. MAJOR CONCERN OF THE DAY
• Theoretical yield potential of rice is 15.9t ha-1
(Yoshida 1981). It can reach 21.6 t ha-1, if
solar energy is efficiently harnessed and
converted (Giese 2009, Agron J 101, 688-695)
• Yield potential of current inbred rice under
irrigated condition is 10 t ha-1(Flinn et
al.,1982; Kropff et al.,1994)
124. Quest for higher yield potential: New
approaches
• Selection for yield components.
• Hybrid rice
• New Plant Type
• Super high yielding hybrid rice
129. Selection of a genotype with only a few large
heavy tillers did not achieve the objective of high
grain yield due to poor partitioning of dry matter.
In heavy panicled indica/japonica hybrid, many
grains remained unfilled (Yang et al., 2002 ;Yuan,
1994) and thus the expected yield potential is
not realised.
147. Observations
• Starch synthesis varies in rice grain differing in kernel types
due to genetic variation or spatial location on panicle axis.
• Sucrose synthase, AGPase, Granule bound starch synthase
and Starch branching enzymes play key role in starch
synthesis.
• Starch accumulation rate and activities of sucrose synthase
and AGPase are higher in large/good quality kernels than
those in small/poor quality grains.
• Emanation of ethylene during grain filling has negative
influence on the process.
• High sterile rice cultivars produce more ethylene and
ethylene impacts grain filling.
148. 1. METABOLIC DOMINANCE OF THE APICAL SPIKELETS OVER THE INFERIOR
BASAL SPIKELETS IS NOT DUE TO DIFFERENTIAL DISTRIBUTION OF
SOLUBLE ASSIMILATES.
2. BASAL SPIKELETS ARE NOT ABLE TO USE THE ASSIMILATES PARTITIONED
IN FAVOUR OF THEM DUE TO POOR ACTIVITY OF SUCROSE SYNTHASE
and AGPASE IN THE ENDOSPERM.
3. THE ACTIVITY OF SUCROSE SYNTHASE AND STARCH FILLING OF
ENDOSPERM, AND GRAIN QUALITY OF SPIKELET ARE AFFECTED BY
ETHYLENE OR ITS PRECURSOR ACC.
4. THE APICAL SPIKELETS REACH ANTHESIS EARLY AND PRODUCE
ETHYLENE WHICH SUPRESSES SPIKELET DEVELOPMENT IN THE BASAL
PART OF THE PANICLE.
5. CONTROL OF ETHYLENE PRODUCTION HOLDS POTENTIAL FOR
IMPROVED GRAIN FILLING.
CONCLUSIONS (Also see Mohapatra et al. Vol 110, Adv. Agron- 2011)
151. Molecular Basis of Poor grain filling
• Differential expression of genes encoding
important enzymes and hormones.
• Varying expression of transporter gene
• Variation in protein expression
• Post-transcriptional gene regulation by
MicroRNAs (miRNAs)
152. Expression profiles of ABA synthesis genes NCED1 and NCED5 and the
ethylene synthesis genes ACO1 and ACO3 in superior and inferior
spikelets during grain filling of rice. From Zhu et al, 2011.
Differential expression of genes encoding important
enzymes and hormones.
153. • Ishimaru et al. (2005) observed that the gene
expressions of vacuolar invertase (INV3), SuSase
(RSus3), and AGPase (AGPL-1 and AGPS2) were
much higher in superior spikelets than in inferior ones at
the early and/or mid-grain-filling stage.
• A cell-wall invertase encoded by the rice GIFI (grain
incomplete filling 1) gene has been found to play a key
role in carbon deposition during early grain-filling and
an overexpression of GIF1 can increase grain-filling and
final grain weight (Wang et al., 2008).
154. Expression of genes related to starch metabolism. From Zhu et
al, 2011 Jr Exp Bot
155. Variation in protein expression
• Expression level of SUS protein in inferior grains
was always lower than that of superior
grains.(Tang et. al, 2009).
156. Post-transcriptional gene regulation by MicroRNAs (miRNAs)
• The slow grain-filling and low grain weight of rice
inferior spikelets are attributed partly to differences
in expression and function between superior and
inferior spikelet miRNAs.(Peng et. al, 2011 JXB)
163. Table 1.A. Yield parameters of the main panicle of rice cultivars, Jogesh, Udayagiri and Sidhanta in 2006 (dry season)
B. Yield parameters of the main panicle of rice cultivars, Ramachandi, Mahanadi and Ganjeikali in 2007 (wet season)
A.
Cultivars
Panicle
dry wt. (g)
Panicle
length (cm)
No. of
grains per
panicle
100 grains
wt. (g)
Grain size
Fresh grain
volume
(ml)
Percentage of Percentage
of high
density
grains
Length
(cm)
Breadth
(cm)
Filled grains
Barren
grains
Jogesh 3.57±0.13 24.23±0.87 184.33±5.68 2.73±0.01 1.05±0.00 0.55±0.00 0.043±0.002 69.53±3.47 30.47±2.05 32.34±2.10
Udayagiri 3.01±0.17 23.71±0.57 179.33±5.50 2.20±0.11 0.80±0.01 0.46±0.10 0.035±0.001 79.74±2.86 20.26±2.86 20.18±4.20
Sidhanta 1.89±0.16 21.50±0.50 163.33±5.50 1.68±0.01 0.70±0.00 0.40±0.01 0.026±0.001 66.12±3.81 33.80±1.81 17.81±2.36
B.
Ramachandi 4.73±0.24 27.40±0.52 195.33±4.72 2.84±0.03 1.08±0.00 0.56±0.00 0.044±0.001 75.33±3.51 24.66±3.51 57.33±2.51
Mahanadi 5.23±0.14 23.66±0.57 251.33±7.50 2.50±0.04 0.90±0.02 0.45±0.05 0.038±0.002 80.66±2.08 19.33±2.08 59.33±4.50
Ganjeikali 6.07±0.22 30.20±0.75 373.6±9.55 1.74±0.06 0.70±0.01 0.42±0.01 0.028±0.001 82.66±3.78 17.33±3.78 61.66±1.15
F value
between the
contrasting
cultivars
0.0139ns
0.3135ns
0.6176ns
73.1*
51.76*
94.16*
274**
1.022ns
0.1031ns
0.3583ns
F value
between
seasons
8.115ns
2.377ns
2.750ns
4.6ns
2.153ns
0.5641ns
12ns
2.82ns
2.843ns
40.31*
The ± values indicate standard deviation of the mean (n = 3). The significance test (F value) for the contrasting cultivars and between seasons were *,
** significant at the 0.05, 0.01 levels of probability respectively and ns
is not significant at the 0.05 level of probability.
164.
165.
166.
167.
168.
169.
170.
171.
172.
173.
174. Observations
• Seed development is genetically programmed.
• Development is prone to control of assimilates.
• Early phase of development is maternally controlled,
switch over is necessary for filial control during
maturation phase (Weber et al 2005).
• Sugar and phyto-hormones navigate responses at the
level of transcription and protein phosphorylation for
change over in control system.
• In the present study impact metabolites and
hormone was assessed during the embryonic phase
when seed development was under maternal
control.
175. Inferences
• Significant differences existed in sugar
concentrations of pericarp, apoplasm and
endosperm of rice cultivars: concentration was
low when seed weight was low.
• Concentration of apoplasmic assimilates always
correlated positively with seed size and weight
but it similar correlations were not found for
pericarp and endosperm assimilates.
• Assimilates provided by maternal tissue during
early part of endosperm growth is crucial for
grain weight and size.
176. Inferences
• Developing endosperm+ embryo remain confined
within embryonic space and do not have any
alternative for assimilates or hormones.
• Endosperm cell number increases rapidly and
positional disadvantage in supply limits cell
multiplication.
• Low sink efficiency restricts assimilate utilization
and increases assimilate concentration of
endosperm and pericarp during later stages.
177. Inferences
• Negative correlations are observed consistently between
apoplasmic assimilates and those of pericarp and endosperm
and it was more evident in the inferior spikelet.
• It establishes the association of maternal tissue in restricting
supply of assimilates to endosperm.
• Poor unloading of assimilates increases concentration in
pericarp and decreases it in apoplasmic space of inferior
spikelets.
• Because concentration solutes of apoplasmic space
determines turgor driven mass flow, starch synthesis of
endosperm is reduced.
178. Inferences
• Ethylene is the hormone responsible for
decreasing activities of pericarp and
endosperm during pre-storage phase.
• High concentration of ethylene reduces cell
division rate, grain filling rate and starch
synthesising enzymes.
• Ethylene induced senescence of pericarp
reduced carrier mediated transport of sugars.
179.
180. Words in green are links…
(From left) Prof. Elizabeth Woods, Chair of the IRRI Board, Prof. Pravat K. Mohapatra and IRRI
Director-General Bob Zeigler
Indian scientist gets 2010 Yoshida Award for Rice Physiology Research
At the International Rice Congress held last week in Hanoi, Vietnam, Prof.
Pravat K. Mohapatra from Sambalpur University, India received the 2010
Yoshida Award for Rice Physiology Research.
As an emeritus scientist honored by the Council of Scientific and Industrial
Research in New Delhi, India, Dr. Mohapatra has devoted his entire career to
improving rice yield potential by studying spikelet development, source-sink
relationship, apical dominance, and architecture of the rice panicle.
He was awarded due to his contributions to research work on the yield
potential of irrigated rice. He found that grain-filling improves when ethylene
action or synthesis is inhibited thus, regulating ethylene responses holds a key
to breaking the yield barrier in irrigated rice. These findings can guide breeders
and physiologists in improving rice yield potential besides from contributing
significantly to existing knowledge.
Made possible through the Shouichi Yoshida Memorial Fund, the Yoshida Award
for Rice Physiology Research was established by IRRI in memory of Dr.
Shouichi Yoshida who was its plant physiology department head until 1984
when he passed away. The award seeks to recognize rice scientists in NARES
institutes linked to IRRI who have made outstanding contributions to rice
physiology research. #
182. INDIA
Tamil Nadu
INDIA
Area – 45 m ha
Production – 87.5 mt
Averg. Productivity – 3.3 t/ha
TAMIL NADU
Area – 19.8 lakh ha
Production – 74 lakh t
Productivity – 3.8 t/ha
RICE SCENARIO
183. Total River basins 17
Sub basins 127
Tanks 39800
Wells 3.70 millions
Net irrigated Area 27.6 lakh ha
Irrigation Intensity 117%
Water Resources of Tamil Nadu
Particulars Quantity
in MHM
Per
centage
Total water supply 4.74 -
Demand for water 6.86 -
Supply-Demand gap 2.12 44.72
Agricultural 5.21 75.95
Non Agricultural 1.65 24.05
SUPPLY & DEMAND
184. WATER CHALLENGES
Degradation of existing water supplies
Degradation of irrigated crop land
Groundwater depletion
Increasing pollution / declining water quality
Poor cost recovery
Trans boundary water disputes
Increasing costs of new water
Virtual water
185. Spatial and temporal variations in water
productivity of rice in Tamil Nadu
Agro-climatic zones
Water productivity (kg m-3 evapo-
transpiration)
Kuruvai Samba Navarai
North Eastern Zone 0.44 0.48 0.47
North Western Zone 0.62 0.59 0.52
Western Zone 0.58 0.49 0.41
Cauvery Delta Zone 0.42 0.33 0.39
Southern Zone 0.41 0.35 0.39
High Rainfall Zone 0.47 0.58 -
High Altitude Zone 0.47 - -
(Ramesh et al., 2009)
186. Tamil Nadu Irrigated Agriculture
Modernization and Water Bodies
Restoration and Management
TN-IAMWARM
Project Period
2007 – 2013
Total Outlay
Rs. 2400 crores
Implementation
63 sub basins
3 phases
187. System of Rice Intensification (SRI)
Younger
seedlings
(14-15 days old)
Reduction in
nursery area &
seed rate
(100 m2/ha
7.5kg/ha
Alternate
wetting
and Drying
Mechanical
weeding
(4 times from
10 DAT)
Square Planting
of single seedling
& wider Spacing
(25 x 25 cm)
Components
188. Research findings on SRI water management
Systems of
cultivation
Recommended
practice
SRI
Irrigated water
(m3/ha)
16634 8419
% water saving - 49.4
(Thiagarajan, 2001)
189. Performance of various soil water regimes in SRI method
Treatments
Grain
yield
(t ha-1)
Days to
panicle
emergen
ce
Water
requireme
nt (mm ha-
1)
Water
use
efficienc
y (kg ha-
1 mm-1)
Productivit
y per day
(kg)
Continuous saturation (SRI) 7.23 110 883 8.19 65
Continuous flooding (5 cm
depth)
5.63 102 1,482 3.79 55
Intermittent flooding (5 cm) 4
DADW
6.34 104 1,025 6.18 61
Intermittent flooding (5 cm) 6
DADW
5.42 104 814 6.65 52
Intermittent flooding (5 cm) 8
DADW
4.52 106 725 6.23 43
CD (p=0.05) 0.81 2.1
(Raju and Sreenivas, 2008)* DADW - days alternate drying and wetting
190. TNAU - TN-IAMWARM PROJECT
Year
SRI Area
(ha)
Yield kg ha-1
SRI Conventional % increase
2007 – 08 4628 5709 4465 28.3
2008 – 09 13362 6710 5035 38.3
2009 – 10 14878 7058 5139 37.3
Beneficiary wise analyses
Year
Percent increase in yield over the conventional
< 10% 10-20% 20-30% 30-40%
40-
50%
>50%
Total
Number
2007-08 337 311 363 301 144 - 1456
2008-09 - 568 678 1004 387 392 3029
2009-10 71 567 543 331 2790 943 5245
Total 408 1446 1584 1736 3321 1335 9730
191. Observations
L1 L2 L3 L4
Overall
average
SRI Convl. SRI Convl. SRI Convl. SRI Convl. SRI Convl.
Water used
(mm)
923 1252 973 1223 827 1148 818 1098 885 1180
Productive
tillers per hill 31.3 9.6 48 31 36 13 39 14 39 17
Productive
tillers per m2 470 350 612 505 720 580 780 704 646 535
Grain yield
(kg/ha)
5810 4450 5982 5032 7046 5965 6784 5689 6406 5284
Water use
efficiency
(kg/ha/mm)
6.28 3.55 6.14 4.11 8.51 5.20 8.29 5.18 7.31 4.51
Water
productivity
(lit/kg of
paddy)
1588 2813 1626 2430 1174 1924 1205 1930 1398 2274
Water Productivity in System of rice intensification (SRI) 2010-11
L1 – Karumaniar sub basin (Tirunelveli Dt.), L2 – Sevalaperiar sub basin (Virudhunagar Dt.),
L3 – Ongur sub basin (Chengalpattu Dt.) and L4 – Nallavur sub basin (Villuppuram Dt.)
192. Comparison of SRI and conventional method of rice cultivation on grain
yield, water use efficiency and economics in TN-IAMWARM Project
Manimuthar sub basin
Particulars
Pooled mean
(2007-2010)
SRI Conventional
No. of productive tillers m-2 627 531
Yield (kg ha-1) 5,485 4,329
Per cent yield increase 26.7 -
Total water use (mm) 1,061 1,360
Per cent water saving by SRI 23.6 -
Water use efficiency (kg ha-1 mm-1) 5.18 3.15
Cost of cultivation (Rs. ha-1) 20,364 23,001
(Veeraputhiran et al., 2010)
193. Water requirement- SRI vs Conventional
600
700
800
900
1 2 3 4 5 6 7 8 9 10
Waterquantityinmm
Total water used
SRI 679mm
Conventional 869mm
SRI fields (1-8) Conventional- 9,10
Saving
28%
Pennaiar sub basin
194. Accelerated growth rate in SRI plants as
these are able to complete more phyllochrons
before entering into their reproductive phase
(Nemoto et al., 1995; Berkelaar, 2001).
This led to both higher tillers per hill and
enhanced the production of effective tillers.
Younger seedlings have improved root
characteristics like root length density and
root weight after transplanting than do aged
seedlings (Mishra and Salokhe, 2008)
Planting of younger seedlings
195. Wider spacing
Open plant structure in SRI covered more ground area
and was able to intercept more light.
This resulted in higher LAI and greater leaf size that led to
vigorous root system and have more adequate room to
grow.
At closer spacing between rice plants the number of
panicles in unit area increases but with shorter panicles
containing lesser grains thereby resulted in lesser yield in
conventional rice cultivation (Thakur, et al., 2010).
196. Rice grown under conventional system creates hypoxic soil
condition and its roots degenerate under flooding, losing
three-fourth of their roots by the time the plants reach the
flowering stage (Kar et al., 1974).
Alternate wetting and drying combined with mechanical
weeding resulted in air in the soil and greater root growth for
better access to nutrients as compared to conventional
planting.
SRI plants have deeper and stronger root systems, supported
by intermittent irrigation practiced on soils without physical
barriers to root growth (Stoop et al., 2002).
Alternate wetting and drying
197. Changes in crop growth rate (CGR) for rice plants during
vegetative stage grown under SRI and RMP (recommended
management practices). Closed and open circles represent
SRI and RMP respectively (Thakur et al., 2010 ).
0
10
20
30
40
50
60
30-40 40-50 50-60 60-70
Period (Days after germination)
CGR(gm-2
day-1
)
SRI
RMP
198. Plant physiological factors contributing
to high yields (under SRI)
• Interdependence between below-ground (roots) and above-ground
(foliage) plant organs.
• Active and extensive root system prolongs leaf age and activity
through higher leaf-N and leaf chlorophyll contents.
• Functioning of lower (older) leaves critical in maintaining viability of
root system.
• Prolonged physiological activity of foliage leads to an extension of
the grainfilling process, heavier individual grains and increased grain
yield.
200. Comparison of leaf chlorophyll- and nitrogen contents
during the reproductive phase for conventional irrigated
and SRI (Thakur et al., 2010; Mishra and Salokhe, 2010)
201. Implications of soil conditions for root
development : impact on canopy development
and nutrient use efficiency
• Soil condition not only as physical and chemical, but also biological
(i.e. living) entity
• Any soil constraint that restricts root development is reflected in a
reduced above-ground canopy development (i.e. tillering process)
• Interdependencies between roots and soil (beyond just water and
nutrient uptake) and increasingly as root development is more profuse
• Under SRI :
– enhanced (early) root growth
– aerobic soil condition: diverse and abundant soil micro-organisms
– favourable organic matter mineralisation: response to organic fertilisers
(counter to flooded soil conditions) greater nutrient uptake efficiency
– soil constraints reduced canopy development increased plant
populations to optimise use of solar radiation
203. Effect of fertilizer N rates on grain yield and straw weight
under SRI and TF (Traditional Flooding) (Thakur et al., 2010)
0
1
2
3
4
5
6
7
8
9
N0 N60 N90 N120
N Fertilizer rates (kg ha
-1
)
Grainorstrawyield(tha
-1
)
SRI-grain
SRI-straw
TF-grain
TF-straw
204. Treatments
Root volume (ml
plant-1)
Root weight (g hill-1)
Grain yield
t ha-1
Conventional SRI Conventional SRI Conventional SRI
MTU 1071 12.4 26.2 5.36 11.7 4.34 5.94
Samba Mahsuri 13.5 31.5 6.14 13.5 4.11 5.79
MTU 1032 11.6 23.7 4.73 9.9 3.88 4.80
MTU 2716 10.1 22.8 4.18 9.6 3.58 3.96
Swarna 35.6 85.1 8.90 17.9 5.64 7.24
Indra 12.5 31.9 6.24 15.3 5.26 6.47
CD (p=0.05) 7.8 3.7 0.32
Root growth under SRI method during wet seasons (mean of two years)
(Raju and Sreenivas, 2008)
205. Comparison of grain yield, grains panicle-1, grain filling percentage, and panicle number of different
varieties and hybrids under SRI and conventional transplanting system (CTS)
Varieties and
duration
(days)
Grain yield (t ha-1) Total grains panicle-1 Grain filling per cent
Panicle number
(m-2)
SRI CTS Mean SRI CTS Mean SRI CTS
Mea
n
SRI CTS
Mea
n
Khandagiri
(90)
4.25 3.18 3.72 130 94 112 82 73 77 285 249 267
Lalat (110) 5.68 4.16 4.92 156 114 135 85 76 80 337 313 325
Surendra (130) 6.25 4.39 5.32 164 132 148 86 77 82 339 315 327
CRHR-7 (135) 6.06 5.37 5.72 163 114 138 84 81 83 341 350 345
Savitri (145) 6.26 5.12 5.69 171 136 154 86 83 85 391 369 380
Mean 5.70 4.45 157 118 84 78 338 319
Practic
e
Variety P x V Practice Variety P x V Practice Variety P x V Practice Variety P x V
LSD (5%) 0.17 0.16 0.23 4.2 7.2 10.2 1.6 2.3 3.3 3.6 19.5 27.6
(Thakur et al., 2009)
206. Single seedling planting,
row planting,
wider spacing,
intercultivation
were practiced
a century ago in India
Visit : www.sri-india.net (SRI Newsletter 6)
207. CONCLUSIONS
SRI is not a fixed package of technical specifications
'Seeing is believing' is true in SRI adoption by farmers
“SRI is the Answer for Food Security &
Mitigation of climate change”
208. “Poor people in Asia
can live without
many things in life,
but they cannot live
without rice.”
Professor M. Yunus
Managing Director,
Grammen Bank,
Bangladesh
209. “Integrated Weed Management
Techniques with Brown manuring at
Different Levels of N under Direct
Seeded Aerobic Rice.”
SEEMA and P.S.BISHT
Department of Agronomy
GBPUA & T, Pantnagar
Uttarakhand
210.
211. OBJECTIVE
• To study the effect of N level and weed control
methods under aerobic condition
• To study the rate of nitrogen along with brown
manuring suitable for aerobic rice
212. Location
Climate of the location
Soil characteristics
Design of the experiment
• SPD
• Main plot – Nitrogen dose
• Sub-plot- weed management practices
EXPERIMENTAL
DETAILS
213. TREATMENT DETAILS
PE- Pre emergence application of Pendimethalin (1.0 kg a.i. /ha)
BM-brown manuring
MW-Mechanical weeding
•N75 =75 kg N/ha
•N100 =100 kg N/ha
• N125 =125 kg N/haNitrogen levels
•W1 =PE+ BM+ 1HW(60 DAS)
•W2 =PE+2MW(20 & 40 DAS)
•W3 =PE+BM
• W4 =Two MW(20 & 40 DAS)
• W5 =Control
Weed management
practices
228. India 2006-7 – Dr Prakash a.o.,
Agricultural Faculty of U.of Bangalore
229. Silicic acid / boron‟s effect on rice
Effect of stabilized
silicic and boric acid
(OSAB3) on rice
Ongoing trials since
2006
3-4 sprays with 1/1,5 L
OSAB3/ha/crop cycle
Prakash, Chandrashekhar,
Mahendra,Thippeshappa,
Patil, Laane
Journal of Plant Nutrition 2011
230. Treatments
Plant
height (cm)
No. of
panicle
Panicle
length (cm)
Grain yield
(Kg ha-1)
Straw yield
(Kg ha-1)
T1 –Control (NPK, Pest.) 91 8 20 5057 7261
T2 - 2 ml L-1 OS (no Pest.) 95 8 21 5932 8294
T3 - 4 ml L-1 OS 97 10 22 6380 8929
T4 - 8 ml L-1 OS 93 7 20 5474 7392
T5 - 2 ml L-1 OS + ½ dose
Pesticide 93 8 21 6022 8759
T6 - 4 ml L-1 OS + ½ dose
Pesticide 96 9 22 6679 9697
T7 - 8 ml L-1 OS + ½ dose
Pesticide 93 7 20 5424 7326
SEM 2 1 1 174 99
CD (5 %) 5 2 2 428 244
Effect of OSAB3 as a foliar spray on growth and yield
parameters in wetland rice during Kharif 2007
231. Effects of (foliar) OSAB3 on yield parameters
of rice in Karnataka 2008-2009
- Wetland rice (Mudigere) Summer 2008/9
4 ml OSAB3 / L + 50% pesticides:
rice: + 5 – 33%; straw: + 15 – 45%
- Wetland rice (Mangalore at ZARS, Kandandy) Summer 2008/9
4 ml OSAB3 / L + 50% pesticides:
rice: + 20 - 35%; straw + 25 – 50%
- Aerobic rice (Shettigere) Summer 2008/9
4 ml OSAB3 / L + 50% pesticides:
rice: + 20 - 60%; straw: + 30 – 55%
232. “Each plant has a Si problem”
The importance of silicon for plants is still
underestimated
Up till now silicon deficiency in plants is
supposed to be „a limited problem‟.
For example in the Rice Knowledge Bank of the
IRRI (International Rice Research Institute) the
symptoms and effects of silicon deficiency are
mentioned: “not very common in irrigated rice”.
WHY
This view is based on the presence of large (=
„enough‟) quantities of SiO2 & silicates in most
soils.
233. Most plants do have
a silicon problem
Most plants have „a silicon problem’
Cause: an inadequate uptake of bioavailable SA .
WHY?
1. Plants need silicic acid and not „silicon‟;
2. Transformation from silicates / SiO2 into (mono)silicic
acid is a limited process;
3. Monosilicic acid is a very instable molecule with high
tendency to polymerize;
4. Result: (very) low concentration of (mono) silicic acid,
often to low for the plant;
5. Due to crop removal (harvesting) each year substantial
amounts of „silicon‟ are removed.
234. Why foliar spray?
So far all results with Si have been obtained by
trials with silicates in the soil uptake via the
roots.
Since 1995 the use of silicon creams for
humans appeared to be effective.
Based on this dermal application principle a
silicon spray was designed for plants.
First test with foliar silicic acid started in 2000
showing spectacular effects: healthier plants.
2003: the combination of silicic/boric spray is
more effective than silicic spray alone.
236. Crop/species Land / year Results Improvement
Strawberry Netherlands / 2005 Shelf life > 1 week
Cherries Italy / 2008 Ticker skin + 14%
Watermelon Spain / 2006 Higher yield, thicker skin, higher Ca
content, less Fusarium
Soluble solids: + 10%
Potatoes
Unions
Netherlands / 2003 Increased weight; less infections Yield: + 6%
Yield: + 10%
Pear SA / 2003
France / 2006
Thicker skin, more equal seize of pears,
higher yield; higher sugar content
Yield: + 15%
Apple SA / 2003
Belgium 2004
Netherlands 2004-08
Thicker skin, more equal seize of apples,
higher yield; higher sugar content
Hardness up 0,5 – pt.
Yield: +17%
Papayas Colombia 2007-2008 Stem ticker, tree longer, higher yield,
more soluble solids
Yield: + 13%
Rice India 2007-2010 Higher yield, higher straw; reduction of
insecticides/pesticides with 50%
Yield: + 15–45%
Straw: + 20-50%
Results of silicic/boric acid foliar
sprays (OSAB3) on different crops
More yield, but what about quality ?
237. Effects of foliar OSAB3 on growth
parameters of Grapes (Bangalore blue)
Treatments Cane length
(cm)
Leaf area
(cm2)
Leaf total
chlorophyll
content (mg g-1)
T1- Control 89.84 155.46 6.93
T2- SA spray 2ml L-1 once in 10 days (6 sprays) 91.13 161.01 10.66
T3- SA spray 4ml L-1 once in 10 days (6 sprays) 110.09 179.44 13.73
T4- SA spray 6ml L-1 once in 10 days (6 sprays) 107.77 176.81 11.41
T5- SA spray 2ml L-1 once in 20 days (3 sprays) 95.15 164.38 8.89
T6- SA spray 4ml L-1 once in 20 days (3 sprays) 98.15 175.90 12.21
238. Effects of OSAB3 on yield parameters
of Bangalore blue grapes
Treatments
Number of
bunches per
vine
Yield per vine
(Kg)
Estimated Yield
per hectare (t)
T1- Control 295.20 26.68 12.01
T2- SA spray 2ml L-1 once in 10 days (6 sprays) 283.27 31.87 14.34
T3- SA spray 4ml L-1 once in 10 days (6 sprays) 325.53 33.87 15.24
T4- SA spray 6ml L-1 once in 10 days (6 sprays) 301.00 37.19 16.74
T5- SA spray 2ml L-1 once in 20 days (3 sprays) 294.00 29.52 13.29
T6- SA spray 4ml L-1 once in 20 days (3 sprays) 298.00 36.14 16.26
T7- SA spray 6ml L-1 once in 20 days (3 sprays) 296.60 27.86 12.54
240. Influence on metabolism
Silicon has an
important regulatory
function on the uptake
and transport of other
minerals.
A = Untreated
B = Treated with Silicon
Mineral uptake
Foliar silicic/boric acid:
- Improves nutrient
uptake via roots
- Improves plant growth
and development
- Larger plants, more
biomass
- More chlorophyll
- Higher yield
- Improved seed quality
- Lower post harvest
food losses
241. Conclusions
With OSAB3 (silicic &
boric acid) we have
proven that this spray
is not a fertilizer, but
a plant growth
promoter.
The silicic acid
technology (SAT) is
easy to apply, (cost-)
effective, safe and
eco friendly.
Thxs !
242. Silicates foliar versus SA foliar
Effect of root and foliar applications of soluble
silicon on powdery mildew control and growth of
wheat plants
Authors: M.-H. Guével, J. G. Menzies and R. R. Bélanger
Soluble silicon = potassium silicate
Although less effective than root applications, foliar
treatments with both Si and nutrient salt solutions led to
a significant reduction of powdery mildew on wheat
plants.
In our experiments, Si amendment, either through the
roots or the leaves, did not increase plant growth.
243. Silicates foliar versus SA foliar
Potassium Silicate as
Foliar Spray and Rice
Blast Control
G.B. Bucka; G.H. Korndorfer; A. Nollaa; L. Coelho
Affiliation: GPSi ICIAG/UFU, Uberlandia, MG, Brazil
Silicon = potassium silicate
Potassium silicate on the
leaves did not increase Si
absorption or accumulation
by the rice plant
There was a reduction on
blast incidence
244. Can we liquify rock?
Yes, we can!
Can we grow paddy ‘on the rock?
Yes, we can!
Why? SILICA OSAB3
245. 1. Silicates improve Q of soil
Si promotes restoration of degraded soils and
increases soil fertility
Si increases plant‟s salt resistance
Si neutralizes Al toxicity in acid soils
Si soil amendment reduces nutrient (P, N, K)
leaching and increases plant P- nutrition
246. 2. Silicates as source for silicic acid
Si as SA increases metabolism increase of crop
production and quality
Since 150 years numerous laboratory, greenhouse and field
experiments have shown benefits of silicon fertilization for rice,
corn and other crops. Silicic acid is the key molecule.
Si as SA protects plant against diseases, insect and fungi
attack
The Si accumulation in epidermal tissues is formed to protect and
mechanically strengthen plant tissue: passive immune system.
SA also stimulates the active immune system against numerous
diseases, sometimes more effectively as pesticides/fungicides,
but without negative effects on the environment. Dual action!
Si as SA increases plant drought and heat resistance
The Si fertilizer application can reduce water by 30 to 50%. The
active Si fertilization allows rehabilitation of salt-affected soils.
249. Mean plant height (cm) of wheat using
different Silicic acid foliar spray treatments
70,7794,4366,48Mean
80,0590,1063Kiran-95
75103,7573,10Abadgar
57,2589,4563,33Mehran
0,75
overdose
0,25
normal
Control
250. Why combination silicic and
boric acid?
Tests with Phytophthora infection on potatoes (Bintje)
Effects (compared to control)
- Silicon sprays: +
- Boron sprays: -
- Silicon/Boron: +++
The best results for preventive antifungal activity
and increased plant growth is a Silicon/Boron
combination
251. Si deficiency in plants:
– how to proof this deficiency?
How? Use bioactive silicic acid itself
But it didn‟t exist dus to the polymerization
problem
How?
SA: mono/di silicic acid oligomeric
micro-colloidal macro-colloidal gel
Stabilize and concentrate biocompetent SA
Effective?
Use a foliar spray with s.sw.SA (=bioactive)
252. Silicates M.SA:
Silicates improve
quality of the soil
Silicates „compensate‟
for salt and acid soils
For biological effects:
silicates must be
transformed into MSA.
This is a limited process,
so only (too) few B-SA
will be produced
M.SA = Si(OH)4: the
key Si-molecule:
bioavailable and
biocompatible for plants
and animals
However: M.SA (di-SA)
= very unstable
Very low concentrations
253. Dr. K.S. Subramanian
Professor and Head
Dept. of Nano Science and Technology
Tamil Nadu Agricultural University
Coimbatore – 641 003
Carbon Sequestration Pattern in Rice Systems
254. System of Rice Intensification (SRI)
Favours Carbon Sequestration
• Biomass production
• Rhizospheric Engineering
• Accumulation of biomass carbon
• Passive carbon pools
• Methane reduction
255. Experimental
Systems of Rice Cultivation
SRI
Conventional
Soil
Active C pools (Biomass Carbon, Water soluble C, WSCHO)
Passive C pools (Humic acid, Fulvic Acid, Humin, Glomalin)
Plant
Carbon assimilating enzymes
Biomass production (roots & shoots)
263. Dehydrogenase Activity in Soil (Δ in OD at 485 nm)
Treatments M- M+
Flooded
0.152 0.212
Semi- Dry
0.105 0.194
Dry
0.097 0.115
Aerobic
0.062 0.081
M 0.006
I 0.009
M x I 0.013
(Subramanian et al. 2009)
266. Conclusions
SRI cultivation assists in Carbon sequestration by
reducing methane emission to the atmosphere
while accumulating glomalin in soil
Intense biological activity associated with SRI
favour passive carbon pool
