Direct seeded rice – A promising resource efficient technology

June 29th, 2017

Arjun Bhattarai, a 51-year-old farmer living in Koshi Haraicha of Morang district, grows rice as a major crop in his land. Out of his three children, a daughter and a son are blind by birth. So, with the help of his only wife and some casual workers, he used to grow rice and vegetables in his own 8 kattha (1 Kattha = 333.33 sq. meter) and leased 10 kattha land. They were able to hardly meet their annual household needs. Moreover, technical issues like lack of knowledge concerning cultivation techniques, suitable seed variety, pest and diseases, irrigation facility and unavailability of labour in the time of need have made them more vulnerable.

Arjun sowing rice seeds using a drum seeder. (c) Practical Action/Prabin Gurung

He joined a Pilot Programme for Climate Resilient Agriculture (PPCR) -Rice training and demonstration plot activity in April 2014 with the hope of getting technical support to improve his farming practice and productivity while reducing the cost of cultivation.He showed keen interest in developing a demonstration plot in his own land. However, he was quiet hesitant to try the new technology of Direct Seeded Rice (DSR) in his land. He was afraid that whether or not the new technology would give the same production as the traditional transplanting technology.

What is DSR?

Direct Seeded Rice (DSR) is a resource efficient technology that can overcome constraints and limitations of traditional cultivation technology. Various constraints of traditional cultivation technology like higher water and labour demand, extra expenses during raising nursery, uprooting and transplanting, uncertain supply of irrigation water and increased frequency of drought has necessitated alternative techniques like DSR that not only reduces the cost of production but also assure its sustainability.

DSR is not common in Nepal because of lack of technical knowhow, marginal and scattered land, low land holding capacity of Nepalese farmers and poor irrigation facilities. There are some basic requirements for successful direct seeding like, big plot of well leveled land, more than 0.25 ha (1 ha = 10000sq. meter), large enough to use a machine; and good irrigation facility so that the land can be irrigated and the water can be drained easily.

Before the project intervention, he had also practiced SRI (System of Rice Intensification) with the help of District Agricultural Development Office (DADO) Morang, with a good productivity. However, as it required lot of skill and labourers, he was unable to continue the technology. In this regards he found DSR as a suitable option to conventional transplanting and modern SRI technology. He says, “Though I was confused on the performance of DSR, I found that this technology can reduce labour cost significantly and perform better in poor irrigation facility too.”

Direct seeded rice seedlings 20 days after seeding

Usually in DSR, first 20 days after seeding is the most important period and critical for successful establishment. If irrigation water is not under control then DSR plants cannot develop as per the expectation. During this initial phase of establishment of seedlings, irrigation should be done just to saturate the field. If irrigation water is above the saturation threshold, i.e., standing water in field then it affects emergence and early development of seedlings, and the seedlings can even die.

More yield with less input

Arjun used to produce 4 mann ( 1 mann =  40 kgs) per kattha but this time he was able to produce 5 mann rice per kattha, also his cost of production was reduced by 25% as he used only two labourers during his entire cropping period.  In DSR, the labour required for nursery raising, uprooting and transplanting of seedlings are saved to the extent of about 40% and up to 50% water is saved as nursery raising, puddling, seepage and percolation are eliminated. The fertiliser use efficiency is increased and early maturity (15-20 days) helps in timely sowing of succeeding crops. Likewise, up to 50% energy is saved because of elimination of field preparation for nursery raising, puddling and reduced water application for irrigation. Even the methane emission is reduced and the soil structure is not disturbed as in puddled transplanted system. And the elimination of transplanting means less drudgery to farm women labourers. Also the cost of cultivation is reduced due to the reduced labour and energy costs.

Direct seeded rice 40 days after seeding

Challenges in DSR cultivation

However, while cultivating DSR, farmers in Nepal face challenges like land topography, irrigation and drainage facility, and availability of inputs like herbicides and lack of technical know-how.

Weed is a major problem in DSR, and it can be only managed through proper time management, controlling and weed-free irrigation system. Most of the irrigation water in Nepal comes through irrigation canals that are fully contaminated with weed seeds and also this irrigation water is uncontrollable, periodic and not sufficient for good production.

In this regards, we have identified possible consideration and modification that have to be applied while practising DSR method of rice production in Nepalese context. Based on our experiences, we have developed following intervention to achieve significant results, thereby reducing weed infestation.

1. Use of Glyphosate: Glyphosate is a non-selective herbicide that kills all grasses and weed. It should be sprayed before land preparation. However, use of glyphosate should be limited only to those plots which have higher weed infestation and are lying fallow for a long period.

2. Suitable land selection and Controlled irrigation: Usually DSR can be cultivated in all types of soil and land. However, due to difficulty in irrigation water management, upland lands are more suitable than flood-prone lowland.

3. Use of post emergence herbicide (15-20days after seeding): Post emergence herbicides like 2-4 D and Nominee gold (Bispyribec) are being used to control weeds. Usually these herbicides are used alone or in combination to bring weed concentration below economic threshold.

4. Irrigation Water Management: Care should be taken for first 20 days after seeding. After 15 days, seedling phase enters to tillering phase and irrigation management is not a big problem after that. As we select upland land for DSR, we do not have much flooding problem. For the first 15-20 days, irrigation is done just to saturate soil from irrigation canals or deep borings. After 20 days, irrigation and other management aspects are same as traditional/transplanting technology.

Having learnt about the technical know-how of cultivating DSR, Arjun is happy to continue it over the traditional method. He says, “I was in a dilemma whether or not to try this technology, but now I am confident that I can adopt this technology without any difficulty and even my neighbours are planning to follow this technology.”

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