The problem of the stem borer
The maize stem borer, Chilo partellus, is the most dangerous pest of maize crop. It damages the crop significantly and reduces the yield by 20 per cent but in severe cases the yield loss many be many times more. It lays its eggs on the under surface of the leaf in batches and completes its life cycle in the plant, damaging it. Generally, this menace is controlled by using insecticides, which not only causes environmental pollution, but also increases the cost of production.
Somabhai was also facing major problem of maize stem borer. However, due to economical constrains, he could not afford insecticides and decided to solve the problem himself.
Finding a solution
Somabhai decided to try local plants for addressing the problem. He thought that the leaves of the plants, which remained green throughout the year, could be useful in controlling the stem borer. Looking around he selected a local plant, whose leaves remained green perennially. He then selected Neem for its well known properties for killing insect pests in crops and also onion, as he believed it to be an irritant.
He had to vary the proportion of the ingredients in the composition many times before finally settling down to the present one, which he found to be the most effective.
The herbal formulation
For this formulation, he uses 3 kg leaves of a local plant, freshly collected in the early morning. The leaves are crushed and soaked in a litre of water for one hour. Another four litres of water is then added and the mixture made to boil for 5-10 minutes. This decoction is cooled and filtered. One kg of neem leaves along with 500 g onion leaves are crushed to extract their juice. This is mixed with the filtered decoction and re-filtered for stocking or spraying.
He suggests spraying this formulation at noon, from the top of the plant, as then the pest buries itself in the central stem. This facilitates the entry of the formulation in the bores. According to Somabhai, the formulation when diluted in water in 1:15 ratio gives 50 to 60 per cent pest control. The spraying can safely be done thrice daily at an interval of three days, without any side effects.
Good results in his farm prompted other farmers also to try the formulation in their afrms. Somabhai gave the formulation to many villagers who also reported about 50 per cent control of the maize stem borer with a couple of farmers claiming that their control was over 60 per cent.
Prior art search reveals that the ingredients of the formulation are known for their insecticidal properties. However, no report of the formulation could be found for the control of maize stem borer in patent as well as in non-patent literature. The formulation was tested against maize stem borer in Sadbhav Sanshodhan SRISTI laboratory, Ahmedabad. It was observed that the formulation was effective in controlling the problem upto 55-60 per cent. SRISTI also conducted on-farm experimentation in farmers’ fields at Gandhinagar & Ahmedabad districts of Gujarat where also the formulation showed significant control over the problem.
Stem borers are the most serious maize pests that damage the crop and reduce the yield considerably. Somabhai (50), an illiterate but creative farmer from Sabarkantha has developed an herbal formulation to control the stem borer.
Somabhai lives with his wife and four sons in Moti govandi village, located 13 km away from Khedbrahma, taluka headquarter. The village is predominantly backward with very low literacy level. Almost all of the villagers practice agriculture. Being a rain fed region, crops like maize, cotton and pulses are grown during the monsoons, while rain fed gram is cultivated during the winter.
Using the traditional implements for farming, Somabhai cultivates maize, wheat, mustard and pulses in his 4 ha of calcareous and clayey land, which has little irrigation facility. He has been involved in traditional farming since he was 15 years of age. During the summers, due to unavailability of work in his farm, he works as a labour in other farms.