KASARGOD: Many traditional farmers -- depending on organic manure -- extol cow dung of native breeds. They attribute virtues to the dung of Vechur and Kasaragod Dwarf -- the world's smallest breeds.
A schoolgirl in Kasaragod decided to scientifically prove the common belief but the results surprised her and farmers, too.
"I found that the cow dung of Kasaragod Dwarf and Vechur is the least efficient among the cow dung of eight native breeds," said Arunima M (16), a class XI student of Government Higher Secondary School, Bela East near Kanhangad.
Contrary to popular perception, the cow dung of Holstein Friesians, a dairy cattle from the Netherlands, outperformed all other Indian breeds by a huge margin. Her myth-shattering research done at her home is selected from Kasaragod district for the state-level Sasthra Padham, the science fair organised by the Sarva Shiksha Abhiyan.
The experiment
Arunima selected cow dung of eight natives breeds from Kapila Gaushala, a farm for native breeds, at Periya, and also cow dung of Holstein Friesians from her neighbour's house.
The native breeds are Gir and Kankrej of Gujarat; Gidda and Hallikar of Karnataka; Kasaragod Dwarf, Vechur of Kerala; Ongole of Andhra Pradesh; and Kangayam of Tamil Nadu. She dried the dung of these cows and also Holstein Friesians for easy and uniform manuring. She took soil from the same place and sieved it to remove the stones.
Arunima, who belongs to a farming family, decided to grow long beans, okra, and mustard because they grow fast. She also sowed the seeds in cups without manure.
"That is 'control'. We have to see how the cow dung fare against plain soil," she said. For the sake of repetition, she had 10 cups for every plant in particular manure. In all, she sowed the three types of vegetable seeds in 300 cups -- all with the same access to sunlight and water. Manuring was done once a week. The control cups were not manured.
The observations
She decided to check the time the seeds took to germinate, the length of the plants, the length, and breadth of the leaves, and the thickness of the stem in subsequent weeks.
"For germination, manuring was not required as the seeds sowed in the control cups and other cups shot up on the third day," Arunima said.
After one week, the long beans sowed in Holstein Friesians dung on an average grew up to 12 cm; whereas the seeds manured by the dung of Kasaragod Dwarf and Vechur grew only 5 cm.
Three seeds of long beans sowed in Hallikar dung grew 13cm and the rest seven grew only 2cm tall. In subsequent weeks, the growth evened out, she said.
To her surprise, the plants sowed in the cups without manure grew 9cm tall. "That means, the manure of Dwarf and Vechur was less efficient than plain soil," she said.
After 60 days
After 60 days, the long beans manured by Holstein Friesian dung grew to 128 cm long. Long beans manured by the dung of Dwarf and Vechur grew 22 cm long, which is just 2cm longer than those sowed in cups without manure.
Long beans manured by the dung of Kankrej and Kangayam cows grew 58 cm and 60cm, respectively.
Long beans powered by dungs of Ongole and Halikar grew by 50cm and 51 cm, respectively. The average stem thickness of long beans manured by Holstein dung was 0.8 cm, which was exactly double the thickness of plants that were not manured and also those manured by the dung of Dwarf, Vechur, and Kankrej.
The result surprised organic farmer Narayanan Kannalayam, who grows and conserves 90 varieties of beans. "I have not compared the dungs but I always used the dung of Dwarf for my farming and I thought it is the best," he said. These findings are surprising, he said.
"Arunima's experiment was fueled by curiosity and completely done at her home. It can be replicated by anybody," said Dr Jasmine M Shah, assistant professor, Department of Plant Science, Central University of Kerala. Dr Shah guided and designed the model of the experiment for Arunima.
'Feeds matter not breeds'
Dr P R Suresh, dean of College of Agriculture, Padannakkad, said the feeds determine the quality of dung. "The dung of Holstein fared better because it is given better cattle feed as it is a dairy cow," he said.
The feed, animal's age, and milking status determine the quality of the dung, he said. "Milking cows are fed better so their dung will be better," he said. Dr Shah disagreed. "Dung of eight Indian breeds from the same farm were tested and each dung performed differently," she said.
Arunima said she used the dung of a Kasaragod Dwarf which was milked. Farm owner Dr Nagaratna S Hegde, who has a PhD in cancer biology from Cambridge Research Institute, said all the native breeds in her farm are given the same feed.
"Their intake differs on their size," she said. Dr Shah said the microflora in the gut could be the differentiating factor. "I suspect different breeds have different gut microflora. Only a metagenome analysis can find the microflora diversity in the gut," she said.
"But for a school student, she can complete the experiment by looking at the yield," she said.