Submergence-tolerance paddy varieties for flood-hit farmers

Dr. Hemchandra Saikia

(saikia.hemchandra@rediffmail.com)

Assam is an agrarian state where 70 percent of its total rural population derives its livelihood from its agriculture and allied sector, and there are 27.42 lakh farm families in the state. The average size of operational holdings in the state is 1.10 hectares, and more than 85 percent of holdings are either small or marginal. Paddy is the most important dominant crop of Assam, occupying 2353 lakh ha of area, which is 86.40 percent of the net cropped area of the state and 97.64 percent of the total cereal area of the state. Among paddy crops, winter rice (Sali Paddy) is the most dominant paddy crop in the state. The average productivity of paddy in Assam is 1886 kg per hectare against the appreciable productivity of paddy in Punjab with 4515 kg per hectare and the world average of 4374 kg per hectare. That means in Assam there is still vast scope to enhance the productivity of paddy on a sustainable basis, which ultimately can sustain both production of paddy and income from paddy for our esteemed paddy farmers and thereby can contribute to the process of economic development of our state as a whole.

In Assam its agriculture is greatly affected by host of critical factors like flood and erosion, pest and disease attack, drought or scanty rainfall, small and fragmented operational holding, quality seed or planting material are not easily available and accessible, inadequate irrigation system, traditional method of crop cultivation, monkey and elephant menace, low level of  mechanization, lack of commercial attitude of farmers,  unscientific method of crop cultivation and fertilizers application,  very insufficient emphasis on producing  desirable value added produce or products, lack of awareness on the part of farming community about very improved method of crop cultivation, government policies and programmes etc. Among these entire problems, flood is one of the most important problems, which affects very badly the agricultural economy of the state of Assam every year, causing big hardship to people, property, animal resources, and other resources, resulting in the loss of a huge sum of money. According to the Rashtriya Barh Ayog, the flood-prone area in Assam is 31500 square kilometres, which is 39.58 percent of the total land area of the state. Floods in Assam damage paddy cultivation to a great extent, as they cometwo to three times a year, and due to this menace, the economy of our paddy farmers in particular and the economy of our state are badly affected.

Importance of submergence-tolerant paddy varieties for flood-affected areas of Assam: To ensure the sustainability of cultivation and production of paddy crops in flood-affected areas of Assam, our paddy farmers need paddy varieties that can withstand waterlogging conditions for several days till the receding of floodwater from our paddy fields. Generally we notice waterlogging conditions prevail due to flooding for 3-7 days or sometimes occasionally for 10 days. To address this problem of waterlogging due to flood for sustaining paddy cultivation and production effectively, Assam Agricultural University, Jorhat, has developed and recommended some very suitable, proven, and potential paddy varieties having high yielding capacity under the waterlogged condition of floodwater at farmers’s fields. These submergence-tolerance paddy varieties can withstand submergence conditions of floodwater for 10-14 days, thereby making paddy cultivation possible for our flood-affected farmers in the state and promoting sustainable paddy cultivation and income from the same.

Paddy varieties developed and recommended by AAU for flood-affected areas: Assam Agricultural University, Jorhat, has developed and recommended more than 67 paddy varieties having high yield potential suitable for cultivation by the farming community across the state. The different paddy varieties, particularly Sali paddy varieties, developed and recommended by Assam Agricultural University, Jorhat, and suitable for cultivation in flood-affected areas are—

1. Ranjit Sub-1: This is a high-yielding Sali paddy variety of 145-150 days duration with a yield potential of 5.5 to 6 tonnes per hectare, and it can withstand submergence in water for 10-12 days and is suitable for cultivation in all zones of Assam. This variety is moderately resistant to neck blast disease and the brown plant hopper insect pest and tolerant to the stem borer insect pest. This variety is emerging as a very popular one due to its encouraging productivity performance at the farmer’s field.

2. Bahadur Sub-1: Submergence-tolerant Sali paddy varieties with 140-145 days duration with a potential yield of 5.5 to 6 tonnes per hectare and can withstand floodwater submergence for 10-12 days. This variety is tolerant to the stem borer insect pest and moderately resistant to the brown plant hopper pest, and its performance is encouraging in farmers fields.

3. BR 11 Sub-1:  This is another submergence-tolerant paddy variety with a 150-day duration, and its potential yield is

4. Swarna Sub-1:  Another submergence-tolerant rice variety suitable for rainfed lowland flash flood situations, its duration is about 140 days. It can withstand 10-12 days of submergence in water.

5.  Jalashree and Jalkunwari: Both are submergence tolerant paddy varieties suitable for rainfed lowland flash flood situation and its crop duration is 150-155 days with an average productivity of 4 tonne per hectare. They are tolerant to bacterial leaf blight and sheath blight and moderately resistant to blast.

6. Bina Dhan 11: Suitable for both the Sali and Boro seasons, and submergence tolerance is up to 14 days with its crop duration of Its potential yield is 5.5 to 6 tonnes per hectare.

7. CR Dhan 801:  A suitable Sali paddy variety for both submergence and drought prune condition and it can withstand submergence condition up to 14 days. Potential yield under submergence conditions is 4 tonnes per hectare, and under drought conditions, 2.9 tonnes per hectare.

8.  CR Dhan 802: This is another Sali paddy variety suitable for both submergence and drought conditions for its cultivation with a crop duration of 140 Yield capacity of this variety is 4.3 tonnes per hectare and 2-3 tonnes per hectare under submergence and drought conditions, respectively.

9.  AAU-TTB Dhan 40 (Dholi): Submergence tolerance Sali paddy variety suitable for multiple cropping with crop duration of 130-135 days and its potential yield is 5-5.5 tonnes per hectare.

Paddy varieties suitable for waterlogged situations:

It is also known that Assam Agricultural University, Jorhat, also has developed and recommended some high-yielding paddy varieties suitable for cultivation under waterlogged situations up to 50 cm, and the duration of these varieties varies from 137 to 139 days. These varieties are suitable for the North Bank Plain, Upper Brahmaputra, Lower Brahmaputra, and Barak Valley Zones of Assam. These varieties are—

1. TTB 303-18-3 (Chakra Lahi): This is a Sali paddy variety with 138 days of crop duration with an average yield of 4.76 tonnes per hectare. This variety is resistant to brown spot disease and moderately resistant to blast and bacterial leaf blight disease. This variety can tolerate sheath blight disease and the stem borer pest.

2. TTB 303-2-23 (Diphalu):  A Sali paddy variety with a crop duration of 137 days and an average potential yield of 5.11 tonnes per hectare. This variety is moderately resistant to blast, brown spot, bacterial leaf blight, and sheath blight disease and found to be tolerant to the stem borer pest.

3. TTB 303-1-42 (Dhansiri): This variety is suitable for the Sali season with its crop duration of about 139 days after seeding and its average yield of 4.84 tonnes per hectare. This variety is found to be moderately resistant to brown spot and sheath blight disease and tolerant to blast, bacterial leaf blight disease, and stem borer pest.

4.  TTB 303-1-26 (Manah): This is also a Sali paddy variety suitable for waterlogged situations up to 50 cm, and it matures in about 138 days after seeding. The potential yield of this variety is 4.66 tonnes per hectare.

Thus, it is seen that there is a good number of proven and potentially high-yielding suitable paddy varieties suitable for cultivation in both flood-affected areas of Assam and also for cultivation under waterlogged situations. Ensuring and encouraging easy availability, accessibility, and affordability of these varieties in due space and time through different institutional means can ensure a satisfactory level of adoption of these paddy varieties. This will thus ensure sustainable cultivation, production, and income from paddy cultivation not only in flood-affected areas but also other cultivable areas across the state. Again, regular and large-scale demonstrations of these paddy varieties suitable for flood-affected areas and waterlogged situations, along with awareness, training, and suitable agro-adversaries through effective institutional interventions and collective effort, have the potential to promote sustainable cultivation, production, and income from paddy cultivation for our farming community, and this effort is very much crucial for sustainable agricultural production in our state.