Organic potatoes surpass yield expected

The National Center for Organic Agriculture (NCOA) has demonstrated that a new potato variety Yusimaap under the organic crop management yielded comparatively good to the conventional method of growing defying findings from studies that it would be drastically low.

The National Potato Program (NPP) under NCOA carried out the Yusimaap cultivation under organic management at Yusimaap comparing the potato yield under organic and conventional management where inorganic fertilizer was used.

It was found that new disease tolerant, Yusimaap yielded 12 to 15 MT per acre under organic crop management compared to 11-15MT per acre under conventional crop management, according to NCOA.

Moreover, the size of seed and tubers was not affected in both the management although a compound fertilizer, Suphala was applied at the rate of 267kgs per acres during planting along with sufficient leaf-mold.    

“Potato depends on use of high amount of fertilizers to give more yield and in organic the yields get down by 30%,” said specialist, NPP, Dr Yadunath Bajgai.

However, he said because of the use of disease tolerant variety, sufficient quantity of organic manure, good cultural management such as crop rotation, use of botanical extracts, and timely weed management lead to a successful story.

Dr Yadunath Bajgai said the Yusimaap was introduced in 2017 in Bhutan as widely grown potato variety in the country; the common potato Desiree has degenerated over the years and only yields 6MT to 8MT per acre on an average.

Additionally, he said Yusimaap is the first nutrient dense variety in the world containing higher levels of iron, zinc, and vitamin C and is resistant to common potato disease, late blight and its yield per acre is almost double.

Growing Yusimaap is demonstrated in 21 gewogs under 13 Dzongkhags conventionally except Gasa Dzongkhag.

“The seed requirement this year is 450MT and the biggest challenge the NPP faces is to produce adequate potato seeds to distribute across the country as seed to production ratio is low,” said Dr Yadunath Bajgai.

The seed requirement per acre is quite big for potato, he said citing example, and 1MT of potato seed would be only adequate for an acre, however, 50kg of mustard would be enough for 5 acres.

The other challenge, Dr Yadunath Bajgai said given the Yusimaap, a high quality, farmers are not willing to share the seeds to other farmers.

He also said the NPPC is working with National Seed Center in Paro and farmers, to multiply and to produce more seeds and would be distributed free to farmers.  The potato is widely consumed as every household buys 2kg to 3kg potato every week and has a shelf life of three months unlike other perishable vegetables, said Dr Yadunath Bajgai adding that he said it is also the most traded commodity in 2019 with export value worth Nu 900mn.

“If we get additional support from the government, it is the crop that can feed our country. Potato can grow in barren land; management is simple, and is grown in every region of the country, he said. In conventional production practice, the easy availability of chemical fertilizers, use of pesticides for weed control and pest management make production easier for farmers however, big advantage of organic production is safe, and healthy food that hugely contributes to the sustainable management of soil and the environment, according to NCOA.

pic courtesy: Ministry of Agriculture and Forest

Thukten Zangpo from Thimphu