CAUVERY DELTA

1. General Information about the Centre

1.1. TRRI, Aduthurai

• 1912 - Started as Research Station at Manganallur
• 1922 -Shifted to Aduthurai as Agricultural Research Station
• 1962 -Upgraded as Regional Research Station
• 1973 -University Research Centre (TNAU) started
• 1981 -State Regional Research Station and University Research Centre merged and named as Tamil Nadu Rice Research Institute and brought under TNAU
• 1985 - Elevated as Directorate

Mandates

• Acts as Co-ordinating Research Centre for rice in Tamil Nadu State, Directorate of Rice Research (Hyderabad), CRRI (Cuttack) and IRRI (Philippines)
• To develop the technologies for rice improvement, agronomic and plant protection management.
• To coordinate the research programmes of all the stations of the state on rice and rice based cropping system research
• To serve as testing and verification centre for the technologies developed at other stations and applicable to the region

1.2. SWMRI, Thanjavur

Soil and Water Management Research Institute, was established in Kattuthottam, Thanjavur during 1972 under department of Agricultural Engineering and first of April 1981, this Institute was taken over by TNAU.

Mandates

• To conduct water management research based on crop water demand, water saving techniques and improving irrigation water efficiency.
• To identify and solve soil related constraints to increase productivity of rice and rice fallow crops

1.3. KVK, Needamangalam (Estd. in 2004)

To conduct FLD and OFT on integrated crop management practices and impart training programme for the farmers, commodity groups and entrepreneurs, etc.,

2. District Wise Basic Information about Cauvery Basin

I. Thanjavur

• Total registered ayacut : 28776.77 ha
• Fully irrigated : 22155.61 ha
• Partially irrigated : 168.9 ha
• Gap: Fallow : 3783.18 ha

II. Thiruvarur

Total registered ayacut : 9331.56 ha

III. Nagapattinam

• Total registered ayacut : 22085 ha
• Fully irrigated : 18814 ha
• Partially irrigated : 169.00ha
• Gap: Falllow : 3112.60 ha

Total ayacut area in Cauvery sub basin

General Information about Districts

Nagapattinam

2.2. Basic information about Cauvery Delta Zone

Cauvery Delta Zone (CDZ) lies in the eastern part of Tamil Nadu between 10.00-11.30, North latitude and between 78.15 – 79.45 longitude. It is bounded by the Bay of Bengal on the East and the Palk straight on the South, Trichy district on the west, Perambalur, Ariyalur districts on the North West, Cuddalore district on the North and Puddukkottai district on the South West.

CDZ has a total geographic land area of 14.47 lakh ha which is equivalent to 11.13 percent of the state area. The erstwhile Thanjavur district occupies 57 percent of CDZ followed by Trichy, Ariyalur, Cuddalore and Pudukkottai districts.

The CDZ has deep and fertile soils. It can be grouped into two categories namely 1) alluvial soil and 2) lateritic soil. Alluvial soil is found to occur in the old delta region comprising the major portion of the zone lying in the northern part whereas, lateritic soil covers new delta region lying in the southern part of the district. The alluvial soil is clayey in texture with 40-45 per cent clay fraction. Predominant clay minerals of alluvial soil are called montmorillonite, which has good capacity for adsorption and 5 retention of water and plant nutrients. But when dry, these alluvial soil cracks widely and deeply because of the presence of expanding montmorillonite clay. On the other hand, lateritic soil of new delta is sandy with less than 25% clay fraction. The dominant clay mineral of lateritic soil is kaolinitic having little capacity for adsorption and retention of water and plant nutrients. In certain pockets, these soils when dry, form hard surface layers (crusting) due to high proportions of free iron and aluminium oxides and hydroxides.

The fertility evaluation of soils revealed that the entire area is low in available nitrogen. With respect to phosphorus, about 80% of the soils (i.e. soils from 27 blocks) have medium content of available P and the remaining 20% of the soils (i.e. soils from 7 blocks) have high content of available P. With regard to potassium, about 70% of the soils (i.e. soils from 24 blocks) have medium content of available K and the remaining 30% of the soils (i.e. soils from 10 blocks) have high content of available K. The low K content is due to the lateritic soils of the new delta region. With reference to micronutrients next to N, the deficiency of zinc is occurring widely. Heavy textured soils of old delta are more deficient in Zinc (80.4%) than the new delta soils (47.4%). Next to Zinc, Copper is deficient in a small extent (19% old delta). The deficiency of iron and manganese is negligible.

Twenty two soil series classified under fourteen soil sub-groups have been identified belonging to the orders of vertisols, entisols, and alfisol in the district. Of these, eight series namely Kalathur, Madukkur, Adanur, Pattukkottai, Padugai, Alathur, Nedumbalam and Melkadu form the major ones.

Clayey, clayey loamy, silty clay, sandy clay, loamy, sandy loam and sandy are the predominant soil texture in CDZ. Clayey and clayey loam in the middle of the delta, sand fraction associated clay more towards the sea coast, loaming nature in new delta area and sandy loam in the western parts of the delta are the most prevalent textures.

The major production constraints that are met with in the CDZ are i) Definite dates of opening and closing of Mettur Dam water for irrigation is not known. This reflects in planning of rice and rice based cropping system. ii) Torrential rains during North East Monsoon, hindering both kuruvai harvest as well as thaladi transplantings. iii) Monocrop of rice in the delta region coupled with unfavorable weather conditions in an year lead to heavy incidence of pests/diseases. iv) Labour shortage during peak season of harvesting or planting v) Lodging of rice crop leads to field germination. Lack of means to preserve kuruvai grain vi) Lack of adequate drainage facility in the delta region vii) Low light intensity prevailing in samba season results in poor yield.

3. Field interventions:

3.1. GM + SRI + Pulses

3.1.1. Restoring soil fertility and enhancing crop productivity through Green Manure –Rice

(SRI)- Rice Fallow Pulses system:

Normal cropping system in the delta is a rice - rice - pulse which has greater tendency for unsustainability mainly due to relatively rapid loss of organic matter, degradation of soil fertility and deterioration in physical, chemical and biological properties. Conventional rice cultivation is a common practice for both kuruvai, samba seasons which leads higher cost of cultivation and more input usage. Non availability water for large size nursery area preparation Scarcity of quality seeds and higher seed cost for large area

The yield obtained by the farmers is around 5000 kg/ha, however the potential yield in the delta is around 7000 kg/ha. So the yield gap is 2000 kg/ha. This may be due to non adoption of proper management practices like soil fertility, poor population maintenance, judicious use of inputs and poor water management, etc.

The interventions proposed Green Manure – Rice –Rice –Rice Fallow pulses will improve (SRI) soil facility and crop productivity

Details of unit cost: Green Manure - Rice - Rice fallow pulse

(i) Details of unit cost: Green Manure

(ii) Details of unit cost: Rice (SRI)

(iii) Details of unit cost: Rice Fallow Pulses

3.1.2. SRI – AWDI -Water saving techniques in rice using Field Water Tube

Nursery cost is more in the conventional system than machine planting.The conventional method of rice growing is not only water-guzzling but also cumbersome and laborious. Rice transplanting requires 200-250 man-h ha-1, which is 25% of the total requirement for the rice crop production.

In kuruvai season, the crop attained maturity during September/October month which is heavily affected by continues rainfall. Manual harvesting consume more time and labour and also yield losses more than 10 - 20 per cent.

Non adoption of water maintenance during critical stage especially tillering stage, milky stage and dough stage, leads to more number of unproductive tiller and chaffy grains.

For adopting the safe AWDI, the depth of ponded water on the field is monitored using a ‘Field Water Tube’ which is made of 40-cm long plastic pipe having a diameter of 15 cm which is perforated with holes on all sides. The tube is dug in the soil so that 15 cm protrudes above the soil surface and the soil from inside is removed so that the bottom of the tube is visible. The water table inside the tube is to be same as outside the tube. The results of network experiments on safe AWDI conducted by the WTC of Tamil Nadu Agricultural University for the past three years revealed that safe AWDI of 10 cm depletion in light soils and 15 cm in heavy soils may be adopted as safe AWDI for improving the water use efficiency in rice. The ponding depth was 5cm after reaching the threshold level. The following observations were also recorded.

• In rice cultivation, conventional flooding should be avoided which consumes huge quantity of irrigation water (as high as 1573 mm)
• The Alternate Wetting and Drying Irrigation (AWDI) will be an appropriate technology for water saving in rice. This technology saves up to 30 percent of irrigation water with an yield increment up to 20 percent.
• 4-5 irrigations were reduced under AWDI when compared to conventional method.
• Considering the depletion levels in AWDI, irrigation once in 6-7 days in sandy loam soils and 8-9 days in clay loam soils may be adopted for improved WUE and productivity of rice.

Interventions suggested: In all the rice growing regions, flooding shall be avoided and the water level beneath the surface may be monitored initially thro’ field water tubes installed @ 5 tubes/ha for standardizing the safe AWDI level. Then the frequency of irrigation could be recommended based on the number of days for each region and soil type.

Details of unit cost: SRI

3.1.3. DSR - Enhancing the rice productivity through complete mechanization (DSR – samba package) (Resilient practice

Transplanted rice requires more number of labours in each field operations like nursery, main field preparation, pulling out of seedlings etc.In case of delay in monsoon or shortage of water, DSR gives the farmer flexibility to take up direct sowing of paddy with a suitable duration variety to fit into the left over season.

Interventions :

• Pulverizing the soil by rotovator in two to three times
• Land leveling by laser leveler
• Seed sowing by seed driller
• Improved Production Technologies in rice

Details of unit cost: DSR

Resilient practice techniques – Kuruvai rice under un-puddled condition and thaladi rice under no till condition by machine transplanting

Rice is grown by transplanting of seedlings (21-30 days age) in puddled fields and for this about 30 percent of water (Total Water Requirement: 1200 mm; 300 mm for puddling; 900mm for growth stages including 50mm for nursery) is required and due to puddling activity, physical changes in soil takes place which are detrimental for non-rice crops due to sub-soil compaction.

Now a day, labour scarcity is a big problem and rice transplanting activity requires about 1/3 of total labour requirement for rice.Due to prevailing monsoon failure

Interventions :

• Pulverising the soil by rotavator in two to three times
• Land levelling by laser leveller
• Transplanting of rice under unpuddled condition by machine

Details of unit cost: RICE

3.3.6. Productivity enhancement in Rice fallow Pulses

• The farmers obtain very low yield due to adoption of traditional varieties, improper foliar nutrient and bio-ferilizers management in pulses.
• Poor crop population under rice fallow condition

Interventions

• Sowing of seeds during 2nd week of January
• Seed priming
• Portable mobile sprinkler for saving the crop during drought and application foliar nutrients
• Create irrigation facilities during later stages of crop by providing pipeline
• IPT for rice fallow pulses

Details of unit cost: Rice Fallow Pulses

3.2. Pulse Seed Production Programme: Production of TFL Seeds under farmers participatory approach to produce quality pulse seeds

• Non availability of quality seed materials during the peak season
• Farmers purchase the seeds locally which fetches more price and also admixture in the seeds
• More incidence of yellow mosaic virus in the traditional varieties

Interventions

• Sowing of seeds during 2nd week of January
• Seed priming
• Portable mobile sprinkler for saving the crop during drought and application foliar nutrients
• Create irrigation facilities during later stages of crop by providing pipeline
• Improved Production Technologies for rice fallow pulses

Details of unit cost: TFL seeds

3.3. Area Expansion and productivity enhancement of pulses under crop diversification in gap areas

• Non availability of quality seed materials during the peak season
• Farmers purchase the seeds locally which fetches more price and also admixture in the seeds
• More incidence of yellow mosaic virus in the traditional varieties

Interventions

• Sowing of seeds during 2nd week of January
• Seed priming
• Portable mobile sprinkler for saving the crop during drought and application foliar nutrients
• Create irrigation facilities during later stages of crop by providing pipeline
• Improved Production Technologies for rice fallow pulses

Details of unit cost: Area expansion pulses

3.4. Demonstration of improved production techniques with various oil seed crops with prime focus on improving productivity, encouraging crop diversification

Low productivity in groundnut is mainly due to poor nutrient availability in the soil, inadequate plant population per unit area and higher percentage of shrivelled kernels.

Intervention :

• Sowing by seed drill
• Micro sprinkler
• Decorticator
• Stripper
• Trap crop of castor/redgram
• IPT for groundnut

Details of unit cost: Oil seeds

Promotion of sustainable Sugarcane Initiative (SSI) in sub basin under precision farming approach.

Details of unit cost: SSI

3.6. Production of vegetable under precision farming mode by adopting of IPM concept. (Cost inclusive of Sustainability and replication on the use of Water soluble fertilizers in the subsequent crops)

• Low productivity in vegetables and high value crop.
• High consumption of water in conventional practices
• Improper nutrient management and other intercultural operation leads to staggered maturity and affect the fruit size and numbers.

Interventions

• Planting of quality culture seedlings
• Proper plant protection treatment for seedlings
• Maintain the uniform pit size
• Adopting paired row system of planting which suit the micro irrigation system
• Applications of fertigation and herbication through drip.

3.7. Promotion of Red Gram (Toor Dhal) under cropping sequence in vegetables

• Introduction of new crop: Redgram + Brinjal system

Details of unit cost: Red gram

3.8. Introduction of new technologies in fruit crops by demonstrating TNAU High density planting with drip fertigation in Mango/Pomegranate etc.

• Low productivity in fruit crop.
• High consumption of water in conventional practices
• Improper nutrient management and other intercultural operation leads to staggered maturity and affect the fruit size and numbers.

Interventions

• Planting of quality culture seedlings
• Proper plant protection treatment for seedlings
• Maintain the uniform pit size
• Adopting paired row system of planting which suit the micro irrigation system.
• Applications of fertigation and herbication through drip.

Details of unit cost: High Density fruit crops

3.9. Crop Diversification in Cauvery Command through Innovative experiments of Introducing New cropping patterns or crops

• Unaware of maize cultivation
• Maize cultivation requires lesser labour as compared to rice resulting in less cost of cultivation.

Interventions :

• Application of macro nutrients such as NPK in adequate quantity during sowing, 25 DAS and 45 DAS
• Sowing with seed drill and harvesting by cob sheller are to be demonstrated in the sub basin which helps to reduce the cost of cultivation.
• Foliar application of maize maxim during critical stages

Details of unit cost: Maize

3.10. Formation of Pulse commodity groups and federated to FPO (Seed to sales)

• Not getting uniform price for their produce due to the intermediaries.

Interventions

3.11. Promotion of Pesticide Free vegetables in sub-basins through climate resilience activity in model Bio Villages known as pesticide free

• Indiscriminate use of pesticides which causes high residue in the produces
• Development of pest resurgence due to usage of synthetic pyrethroids.

Interventions

• Installation of pest monitoring system (light trap, sex pheromone trap, yellow sticky trap)
• Use of bio control agents (Trichogramma speices)
• Use of botanical like neem oil, pungam oil, etc.

3.12. Farm Implements

4. Capacity Building & Information, Education & Communication

4.1. Capacity building

4.1.1. Training to stakeholder

Under this activity, imparting training to all the beneficiaries either as off-campus or as on-campus is planned.

4.1.2. Exposure visit

In-order to have practical knowledge on various improved farming practices prevailing across the District and State, it has been proposed to expose the stakeholders by organizing educational tours for having better cross learning.

4.2. IEC including Awareness creation, documentation and IEC equipment

4.2.1. Organize awareness campaign

Informal meetings with Farmers / Water Users Association through PRA methods – Focus group discussion and transect walk.

• Organizing informal meetings in sub basin villages
• Message on AIR / local cable TV
• Ensure transparency
• Explain about the scheme – organization objectives, activities, project contribution and farmers share
• Emphasis the role of stake holders in the project
• Project the expected benefit

4.2.2. Documentation

• Maintenance of records and registers
• Field note for each activity
• Daily memorandum sheet
• Receipt and issue of inputs
• Technical observations on soil, water and crop
• Printing pamphlets about the scheme
• Wall paintings

4.2.3. IEC Equipments

Purchase of Laptop, Camera and Computer accessories

4.2.4. Out sourcing charges on vehicles

• Expenditure on TA /DA for the purpose of TN-IAM Project
• Fuel bill of university vehicle utilized for the project
• Hire charges of university vehicle utilized for this purpose

5. Management Cost

5.1. Outsourcing of technical staff

Outsourcing of technical staff is included in TNAU sub basin plan to carry out the field activities.

6. Year-wise crop based activities

Cauvery delta sub basin - Thanjavur District

Cauvery delta sub basin - Tiruvarur District

Cauvery delta sub basin - Nagapattinam District

Cauvery delta sub basin: Abstract