PREFACE
The BMGF funded project “Stress Tolerant Rice for Africa and South Asia (STRASA)”
aims primarily at targetting three major stresses- submergence, drought and salinity in
South Asia. In order to tackle the problem of submergence due to flash flooding, a
submergence tolerant gene SUB1 has recently been incorporated by IRRI in several
popular rice varieties of South and Southeast Asia. These varieties can survive two weeks
of complete submergence and still produce a high yield. In India, Swarna-Sub 1, the first
variety with SUB1 gene incorporated in the mega rice variety Swarna (MTU 7029), was
first released in the year 2009. Subsequently, Sambha Mahsuri-Sub1 was released by the
State Variety Release Committee of Uttar Pradesh in 2013. Another variety, IR64-Sub1
has been identified through All India Co-ordinated Rice Improvement Programme
(AICRIP) for release, whereas Ciherang-Sub1 has been nominated for AICRIP testing.
Realizing the potential of Swarna-Sub1 and other Sub1 varieties in increasing rice
production in the submergence- prone rice growing areas of eastern India and Andhra
Pradesh, Govt. of India has been supporting their dissemination through National Food
Security Mission (NFSM) and Bringing Green Revolution to Eastern India (BGREI)
programme by distributing seed minikits (5 kg seeds packets) since Kharif 2010.
Assam, with a net sown area of approx. 2.4 million ha and a rice area of about 2.5 million
ha (both kharif and rabi seasons taken together), has a rice productivity below the
national average (1.73 t/ha compared to national 2.12 t/ha in 2009-10), despite having
good alluvial soils. This is due to the frequent spells of floods and droughts occurring in
the state. An estimated 0.475 million ha area (about 19% of the net sown area) in the state
is chronically flood-prone. Another 94,000 ha area is chronically drought-prone. The
Page 1
state kharif rice yield during 2009-10 was 1.66 t/ha which had been reduced to 1.29
tonnes/ha during the severe flood year of 2007-08.
Even during the last kharif season
(2012), several districts were affected by flood. IR 64 is a popular rice variety in several
districts of Assam and IR64- Sub1 can help in increasing the rice productivity of these
flood-prone areas.
In order to ensure that the seeds of Swarna - Sub1, IR64-Sub1 and other Sub1 varieties,
through NFSM, BGREI programme and other sources, are distributed only in the targeted
environments where its full potential can be harnessed, a study using Satellite Remote
Sensing technique was carried out to identify areas where submergence of about two
weeks or less duration occurs. Flood area information from Radarsat of different dates for
the past four years (2007, 2008, 2009 and 2010) collected from National Remote Sensing
Centre (NRSC) website were analyzed and villages, revenue circles and districts
identified using GIS. The present report covers all the 21 flood-prone districts of Assam
(Baksa, Barpeta, Bongaigaon, Cachar, Chirang, Darrang, Dhemaji, Dibrugarh, Golaghat,
Goalpara, Hailakandi, Jorhat, Kamrup, Karimganj, Lakhimpur, Marigaon, Nagaon,
Nalbari, Sibsagar, Sonitpur and Udalgiri). The report covers 6997 villages spread over 93
revenue circles of these 21 districts, and would be helpful in targeted dissemination of
Sub1 rice varieties by the Government of Assam.
Feedback on this report will be very much appreciated.
U.S.Singh
A.N.Singh
D.D.Sinha
Page 2
C ONTENTS
Page No.
Preface
1
Contents
2
List of Tables, figures and maps
5
Introduction
9
Flooding and submergence in rice and its impact
11
Characteristics of new submergence-tolerant rice varieties
12
Methodology of site suitability analysis
13
Submergence-prone areas suitable for targeted dissemination
14
Summary list of revenue circles and districts suitable for
dissemination of submergence-tolerant rice
18
List of Villages suitable for dissemination of submergence-tolerant rice
in different districts
Barpeta (incl. Baksa)
21
Bongaigaon (incl. Chirang)
27
Cachar
29
Darrang (incl. Udalgiri)
37
Dhemaji
40
Dibrugarh
49
Page 3
Golaghat
62
Golapara
64
Hailakandi
66
Jorhat
68
Kamrup
76
Karimganj
84
Lakhimpur
91
Marigaon
101
Nagaon
109
Nalbari
120
Sibsagar
122
Sonitpur
132
Revenue circle maps showing location of suitable villages
133
Acknowledgement
References
Appendix 1
226
Page 4
List of tables, figures and maps
Page no.
Table 1
Crop area and farm families affected due to flood in Assam (2007-13)
11
Table 2
Summary list of submergence-prone revenue circles and districts
List of submergence-prone villages for targetted dissemination of
Sub1 rice varieties
18
15
Map 2
Flow chart showing the methodology of site suitability analysis
Location of districts for targetted dissemination of Sub 1 rice varieties
in Assam
Submergence-prone areas suitable for targetted dissemination of Sub1
rice varieties in study districts of Assam
Map 3
Site suitability of villages in Baghor revenue circle, Barpeta district
133
Map 4
Site suitability of villages in Bajali revenue circle, Barpeta district
134
Map 5
Site suitability of villages in Barnagar revenue circle, Barpeta district
135
Map 6
136
Map 7
Site suitability of villages in Barpeta revenue circle, Barpeta district
Site suitability of villages in Kalgachiya revenue circle, Barpeta
district
Map 8
Site suitability of villages in Sarupeta revenue circle, Barpeta district
138
Map 9
139
Map 10
Site suitability of villages in Bijni revenue circle, Bongaigaon district
Site suitability of villages in Srijangram revenue circle, Bongaigaon
district
Map 11
Site suitability of villages in Katogora revenue circle, Cachar district
141
Map 12
Site suitability of villages in Lakhipur revenue circle, Cachar district
142
Map 13
Site suitability of villages in Shilachar revenue circle, Cachar district
143
Map 14
Site suitability of villages in Sonai revenue circle, Cachar district
144
Table 3
Figure 1
Map 1
21
10
16
137
Page 5
140
Map 15
Site suitability of villages in Udarband revenue circle, Cachar district
145
Map 16
Site suitability of villages in Dalgaon revenue circle, Darrang district
Site suitability of villages in Mangaldoi revenue circle, Darrang
district
Site suitability of villages in Pathorighat revenue circle, Darrang
district
146
149
Map 20
Site suitability of villages in Sipajhar revenue circle, Darrang district
Site suitability of villages in Dhakuakhana revenue circle, Dhemaji
district
Map 21
Site suitability of villages in Dhemaji revenue circle, Dhemaji district
151
Map 22
Site suitability of villages in Jonai revenue circle, Dhemaji district
Site suitability of villages in Sissibargaon revenue circle, Dhemaji
district
152
Site suitability of villages in Subansiri revenue circle, Dhemaji district
Site suitability of villages in Chabua revenue circle, Dibrugarh
district
Site suitability of villages in Dibrugarh East revenue circle, Dibrugarh
district
Site suitability of villages in Dibrugarh West revenue circle,
Dibrugarh district
154
Site suitability of villages in Moran revenue circle, Dibrugarh district
Site suitability of villages in Naharkatiya revenue circle, Dibrugarh
district
Site suitability of villages in Tengakhat revenue circle, Dibrugarh
district
Site suitability of villages in Tingkhong revenue circle, Dibrugarh
district
Site suitability of villages in Bokaghat revenue circle, Golaghat
district
Site suitability of villages in Dargaon revenue circle, Golaghat
district
Site suitability of villages in Golaghat revenue circle, Golaghat
district
Site suitability of villages in Khumtai revenue circle, Golaghat
district
158
Site suitability of villages in Matia revenue circle, Golapara district
Site suitability of villages in Rangjuli revenue circle, Golapara
district
Site suitability of villages in Algapur revenue circle, Hailakandi
district
Site suitability of villages in Hailakandi revenue circle, Hailakandi
district
166
Map 17
Map 18
Map 19
Map 23
Map 24
Map 25
Map 26
Map 27
Map 28
Map 29
Map 30
Map 31
Map 32
Map 33
Map 34
Map 35
Map 36
Map 37
Map 38
Map 39
Map 40
147
148
150
153
155
156
157
159
160
161
162
163
164
165
167
168
169
Site suitability of villages in Jorhat East revenue circle, Jorhat district
170
Page 6
Map 41
Site suitability of villages in Jorhat West revenue circle, Jorhat
district
171
Map 42
Site suitability of villages in Majuli revenue circle, Jorhat district
172
Map 43
Site suitability of villages in Toek revenue circle, Jorhat district
173
Map 44
Site suitability of villages in Titabor revenue circle, Jorhat district
174
Map 45
175
Map 48
Site suitability of villages in Boko revenue circle, Kamrup district
Site suitability of villages in Chamaria revenue circle, Kamrup
district
Site suitability of villages in Chandrapur revenue circle, Kamrup
district
Site suitability of villages in Chhayagaon revenue circle, Kamrup
district
Map 49
Site suitability of villages in Goreswar revenue circle, Kamrup district
179
Map 50
Site suitability of villages in Hajo revenue circle, Kamrup district
180
Map 46
Map 47
176
177
178
Map 53
Site suitability of villages in Kamalpur revenue circle, Kamrup
district
Site suitability of villages in Nagarbara revenue circle, Kamrup
district
Site suitability of villages in North Guwhati revenue circle, Kamrup
district
Map 54
Site suitability of villages in Palasbari revenue circle, Kamrup district
184
Map 55
Site suitability of villages in Rangia revenue circle, Kamrup district
185
Map 56
Site suitability of villages in Sonapur revenue circle, Kamrup district
Site suitability of villages in Badarpur revenue circle, Karimganj
district
Site suitability of Villages in Karimganj revenue circle, Karimganj
district
Site suitability of Villages in Nilambazar revenue circle, Karimganj
district
Site suitability of Villages in Pathakandi revenue circle, Karimganj
district
Site suitability of villages in Ramkrishna Nagar revenue circle,
Karimganj district
Site suitability of villages in Bihpura revenue circle, Lakhimpur
district
Site suitability of villages in Dhakuakana revenue circle, Lakhimpur
district
Site suitability of villages in Kadam revenue circle, Lakhimpur
district
Site suitability of villages in Naobaicha revenue circle, Lakhimpur
district
186
Map 51
Map 52
Map 57
Map 58
Map 59
Map 60
Map 61
Map 62
Map 63
Map 64
Map 65
181
182
183
Page 7
187
188
189
190
191
192
193
194
195
Map 73
Site suitability of villages in Narayanpur revenue circle, Lakhimpur
district
Site suitability of villages in North Lakhimpur revenue circle,
Lakhimpur district
Site suitability of villages in Subansiri revenue circle, Lakhimpur
district
Site suitability of villages in Bhuragaon revenue circle, Marigaon
district
Site suitability of villages in Laharighat revenue circle, Marigaon
district
Site suitability of villages in Marigaon revenue circle, Marigaon
district
Site suitability of villages in Mayong revenue circle, Marigaon
district
Site suitability of villages in Mikirbheta revenue circle, Marigaon
district
Map 74
Site suitability of villages in Dhing revenue circle, Nagaon district
204
Map 75
Site suitability of villages in Hojai revenue circle, Nagaon district
205
Map 76
Site suitability of villages in Kampur revenue circle, Nagaon district
206
Map 77
Site suitability of villages in Lanka revenue circle, Nagaon district
207
Map 78
Site suitability of villages in Nagaon revenue circle, Nagaon district
208
Map 79
Site suitability of villages in Raha revenue circle, Nagaon district
209
Map 80
Site suitability of villages in Rupahi revenue circle, Nagaon district
210
Map 81
Site suitability of villages in Samaguri revenue circle, Nagaon district
211
Map 82
Site suitability of villages in Barbhag revenue circle, Nalbari district
212
Map 83
Site suitability of villages in Barkhetri revenue circle, Nalbari district
213
Map 84
Site suitability of villages in Amguri revenue circle, Sibsagar district
214
Map 85
215
Map 86
Site suitability of villages in Dimow revenue circle, Sibsagar district
Site suitability of villages in Mahmora revenue circle, Sibsagar
district
Map 87
Site suitability of villages in Nazira revenue circle, Sibsagar district
217
Map 88
Site suitability of villages in Sibsagar revenue circle, Sibsagar district
218
Map 89
Site suitability of villages in Sonari revenue circle, Sibsagar district
Site suitability of villages in Bishwanath revenue circle, Bishwanath
district
Site suitability of villages in Dhekiajuli revenue circle, Bishwanath
district
Site suitability of villages in Gohpur revenue circle, Bishwanath
district
Site suitability of villages in Helem revenue circle, Bishwanath
219
Map 66
Map 67
Map 68
Map 69
Map 70
Map 71
Map 72
Map 90
Map 91
Map 92
Map 93
196
197
198
199
200
201
202
203
Page 8
216
220
221
222
223
Map 94
Map 95
district
Site suitability of villages in Na-Daur revenue circle, Bishwanath
district
Site suitability of villages in Tezpur revenue circle, Murshidabad
district
224
225
Site suitability analysis of submergence-prone areas in Assam
for dissemination of Sub 1 rice varieties
1. Introduction
The Bill and Melinda Gates Foundation (BMGF) –supported project “Stress
Tolerant Rice for Africa and South Asia (STRASA)” is being implemented by the
International Rice Research Institute (IRRI) in seven eastern India states- Assam, Bihar,
Chhatisgarh, Jharkhand, Odisha, Uttar Pradesh and West Bengal.
Assam, with a geographical area of 7.843 Mha and a population of 31.17 million (2011),
is the largest among the seven northeastern states of India. Rice is grown on about 2.55
Mha (average of triennium ending 2011-12), and is the staple food of about 90%
population of the state. The rice productivity of the state is below the national average
(1.80t/ha compared to national 2.18 t/ha in triennium ending 2010-11), despite having
fertile alluvial soils and good rainfall conditions. This is due to the frequent spell of
floods and sometimes occurrence of drought in the state. An estimated 0.5 Mha rice area
in the state is chronically flood-prone and another 0.1 Mha drought-prone. Rice yield in
the flood-prone ecosystem is low and crop failure is common due to abnormal flooding
and uneven distribution of rainfall in this ecosystem.
In order to tackle the problem of submergence due to flash flooding, a submergence
tolerant gene SUB1 has recently been incorporated by IRRI in several popular rice
varieties of South and Southeast Asia. These varieties can survive two weeks of complete
submergence and still produce a high yield. In India, Swarna-Sub 1, the first variety with
Page 9
SUB1 gene incorporated in the mega rice variety Swarna (MTU 7029), was released in
the year 2009. Subsequently, Sambha Mahsuri-Sub1 was released by the State Variety
Release Committee of Uttar Pradesh in 2013. Another variety, IR64-Sub1 has been
identified through All India Co-ordinated Rice Improvement Programme (AICRIP) for
release, whereas Ciherang-Sub1 has been nominated for AICRIP testing. Few other
popular rice varieties of the country with SUB1 gene are also in the process of release.
Swarna and IR-64 are popular rice varieties in several districts of Assam and SwarnaSub1, IR-64 Sub1 and other Sub1 varieties can help in increasing rice productivity of the
flood-prone areas of the state.
Realizing the potential of Swarna-Sub1 and other Sub1 varieties in increasing rice
production in the submergence- prone rice growing areas of eastern India and Andhra
Pradesh, Govt. of India has been supporting their dissemination through National Food
Security Mission (NFSM) and Bringing Green Revolution to Eastern India (BGREI)
programmes by distributing seed minikits (5 kg seeds packets), and conducting large
scale cluster demonstrations.
In order to ensure that the seed distribution and cluster demonstration of Swarna - Sub1
and other Sub1 varieties, through NFSM, BGREI programme and other sources, are
taken up only in the targeted environments where its full potential can be harnessed, a
study using satellite remote sensing technique was carried out to identify areas where
submergence of about two weeks or less duration occurs. Flood area information from
Radarsat of different dates for the past four years (2007, 2008, 2009 and 2010) collected
from National Remote Sensing Centre (NRSC) were analyzed and villages, revenue
circles and districts identified using GIS. The present report covers the 21 flood-prone
districts of Assam viz., (Baksa, Barpeta, Bongaigaon, Cachar, Chirang, Darrang,
Dhemaji, Dibrugarh, Golaghat, Goalpara, Hailakandi, Jorhat, Kamrup, Karimganj,
Lakhimpur, Marigaon, Nagaon, Nalbari, Sibsagar, Sonitpur and Udalgiri). (Map 1).
Map 1. Location map of Districts for Targetted Dissemination of
Sub1 Rice Varieties in Assam
Page 10
2. Flooding and submergence in rice and its impact
Assam has a long recorded history of floods. The flood in Assam is caused by two major
rivers- the mighty Brahmaputra in the north and Barak in the south. Flood in the state
causes a huge destruction and loss to the economy, which is largely agrarian.
Flood frequency and severity: Flood in Assam has been reported to increase after the
1950 earthquake which created extensive landslides in the adjoining hills and rise in the
bed load of river Brahmaputra. Between 1951 to 2000, floods occurred in Assam in 1954,
1962,1966,1972,1974,1977,1978,1984,1986,1987,1988,1989,1990,1991,1992,1993,1994
,1995,1996,1997,1998,1999 and 2000 (source: www.aasc.gov.in). The number of villages
affected by floods between 1982 to 1999 has been reported to exceed 5000 in 1987, 1988,
1991, 1993, 1996, 1997, 1998 and 1999. In the year 1988, about 8700 villages were
affected by flood.
A large extent of cropland is affected by floods in Assam. The crop area and number of
farm families affected in recent years is provided in Table 1.
Table 1. Crop area and farm families affected due to flood in Assam (2007-13)
Year
2007-08
2008-09
2009-10
2010-11
2011-12
2012-13
Area affected
(Mha)
0.455
0.315
-0.187
0.161
0.530
No. Farm families
affected (million)
1.577
0.756
-0.495
0.342
1.238
Remarks
Drought year
Page 11
Floods in the state are caused by high rainfall occurring in the area and also due to water
brought by the rivers from the upper catchments. Flooding and submergence of varying
durations occur during the monsoon season. Flood can begin at the onset of monsoon in
June to early October every year but the timing, severity and frequency vary from year to
year. Moderate to severe flooding occurs every 2 to 3 years, even though mild flooding
( for 2 to 3 days) is common every year (Deka and Gauchan, 2012). Depending on the
severity, number of days of submergence and crop stage during the flood, there may be
complete or partial loss of yield in rice.
3. Characteristics of new submergence-tolerant rice varieties
Following are some of the submergence-tolerant rice varieties with SUB 1 gene, recently
released/ under advance stage of testing in India, and their characteristics:
Swarna- Sub1 (IR 05F102), a rice variety developed by IRRI and released and notified
by the Govt. of India for flash flood-prone areas of eastern India and other states in 2009,
can tolerate complete submergence of about 14 to 17 days. This variety has all other
characteristics of Swarna (also known as Sona Mahsuri or Nati Mahsuri), except for the
submergence tolerance and the lighter husk colour of its grain. Swarna is one of the most
popular high yielding (4.5-7t/ha), long duration (155 days maturity) variety of India and
is also grown in several areas of Assam. Swarna-Sub1 can be a good replacement in
Swarna growing area, where flash flooding is a problem. On an average Swarna-Sub1
offers yield advantage of 1-2 t/ha over Swarna under flooded condition.
IR64-Sub1 (IR07F102), a variety in the process of release, is medium duration (125-130
days maturity) with long slender (fine) grain. IR64 is a popular variety in some districts
of Assam and hence IR64-Sub1 can be good replacement in flood-prone areas of those
districts. The yield is 4-4.5 t/ha.
Sambha Mahsuri-Sub1, a variety released for flood-prone areas of Uttar Pradesh and
other states in 2013, is a semi-dwarf (82-85cm plant height), medium duration variety
(145 days maturity) and has a fine grain quality. This variety has also all the
characteristics of Sambha Mahsuri, a popular variety in several states of India and has the
Page 12
additional advantage of submergence tolerance of about two weeks. The yield is 5.5- 6
t/ha.
Ciherang- Sub1, a variety under advanced stage of testing in India and may be released
soon, has submergence tolerance better than Swarna- Sub1 and Sambha-Sub1. The grain
quality is fine and the yield is also high.
Besides the above rice varieties, CR 1009- Sub1 is also under the process of release.
The above Sub1 incorporated varieties can tolerant complete submergence of about two
to three weeks as described above. Thereafter, the water should recede. In areas where
submergence occurs for longer duration and where water depth of about 25-30 cm or
more remains stagnant even after flood recession, regeneration of the plant may not be
possible. Hence such areas should be avoided.
4. Methodology of Site suitability analysis for targeted dissemination of
submergence-tolerant rice
4.1 Data and maps:
The following data and maps were used for site suitability analysis:
i)
Radarsat based flood maps of different dates from National Remote Sensing
Center ( NRSC), Hyderabad.
ii)
Rice growing areas map from IRRI (Gumma et al., 2011)
iii)
Village,
revenue
circle
and
district
boundary
maps
from
Assam
Administrative Atlas (Census of India, 2001)
4.2 Methodology:
All the available Radarsarsat-2 SAR data based flood maps of the study districts for the
years 2007, 2008, 2009 and 2010 were downloaded from NRSC website and georeferenced. Since for the dissemination of Swarna Sub1 rice, the area selected should
have a water inundation period of 15 days or less, maps of four flood years (2007, 2008,
2009 and 2010) were accordingly selected and digitized for analysis. The list of available
flood layers and utilized for analysis is given in Appendix 1. In each flood year, map
Page 13
showing area with less than 15 days of submergence was prepared based on flood maps
of different dates and then integrated for all the four years using GIS.
The submergence area map was overlaid onto kharif rice map taken from Gumma et al.
(2011) to prepare Swarna-Sub1 potential area map. For the village level information,
revenue circles map of all the study districts were collected from the Assam
Administrative Atlas of the Department of Census, Government of India (2001). These
maps were scanned, geo-referenced and digitized. The Swarna-Sub1 potential area layer
and village layer were brought in the same projection and overlaid to find out the villages
suitable for growing Swarna-Sub1. The villages having only small inundated area (about
10% or less) were excluded from the final village data base. The detailed methodology
flow chart is given in Fig. 1.
5. Submergence-prone areas suitable for targeted dissemination
Based on the methodology described in the previous section, a map showing
submergence-prone areas suitable for targetted dissemination of Sub1 rice varieties in 21
districts of Assam has been prepared (Map 2).
6. List of villages, revenue circles and districts suitable for dissemination of
submergence-tolerant rice
Based on the methodology described in Fig. 1, the list of villages suitable in each revenue
circle of the 21 submergence-prone districts for the dissemination of submergence
tolerant varieties has been prepared. In the 93 revenue circles of 21 districts, where seeds
of these varieties can be distributed, 6697 villages have been identified. Table 2 provides
the summary list of submergence-prone revenue circles in the districts and Table 3
provides the complete list of villages selected for targetted dissemination.
7. Revenue circle maps showing location of suitable villages
Revenue circle-wise maps showing the villages selected for targetted dissemination of
submergence tolerant rice varieties are provided in this report (Map 3 to 95). These maps
show the location of villages that are suitable for dissemination of submergence-tolerant
rice varieties.
Page 14
Flood layer 1
Year 1
(2007)
Flood
layer 2
Year 2
(2008)
Flood layer 3
Year 3
(2009)
Flood layer 4
Year 4
(2010)
Permanent water
body / wetland
layer
Permanent
water body
/ wetland
layer
Permanent
water body /
wetland layer
Permanent
water body /
wetland layer
Flood duration of
15 days or less
Flood
duration of
15 days or
less
Flood
duration of
15 days or
less
Flood
duration of 15
days or less
Rice area layer (WS)
Swarna Sub-1 Potential Area Map
District, blocks and revenue circle boundary layer
Villages / Revenue Circle / Districts suitable or
Swarna-Sub1 Dissemination
Page 15
Fig.1 Methodology for Targetted Dissemination of Swarna-Sub1 and other Sub1
rice varieties
Rice area layer (WS)
Swarna Sub-1 Potential Area Map
District, blocks and village boundary layer
Villages / Blocks / Districts for
Swarna-Sub1 Dissemination
Page 16
Acknowledgement
Authors acknowledge funding support from Bill and Melinda Gates Foundation for the
STRASA project under which the study was taken up. We also acknowledge National
Remote Sensing Center (NRSC), Hyderabad for making Radarsat-2 based flood
inundation maps available on their website.
References
Census of India (2001). Administrative Atlas, Assam. Directorate of Census Operation,
Assam, 361p.
Deka, N. and Gauchan, D. (2012) Pattern of adoption of improved rice varieties and
farm-level impacts in stress-prone rainfed areas of Assam, India. In Pandey, S, Gauchan
D, Malabayabas M, Bool-Emrick M., varieties and farm-level impacts in stress-prone
rainfed area in South Asia. Los Banos (Philippines); International Rice Research
Institute. 318p.
Gumma, M.K., Nelson, A., Thenkabil, P.S. and Singh, A. N. (2011) Mapping rice areas
of South Asia using MODIS multitemporal data. J. Appl. Remote Sens.5, 053547 (online
on Sept1, 2011)
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