The Hindu Business Line : Now, a cotton that can grow in spring

CULTIVATION of spring-summer cotton varieties may soon be a reality in the country, with the Indian Agricultural Research Institute (IARI) successfully testing out genotypes that yield up to two tonnes of kapas (seed cotton) per hectare sans any application of pesticides or recourse to Bt-type genetic engineering.

Cotton in India is basically a kharif crop sown from around May in North-West India (mainly Punjab, Haryana and northern Rajasthan), which stretches up to July-August in Tamil Nadu. The crop normally grows for about 150 days through the monsoon season (June-September) and can yield roughly three tonnes per hectare.

What the IARI is now working on are genotypes that can be planted in February-March and harvested not later than June 30, prior to the onset of the monsoon. In fact, the institute — which has been the laboratory for the country's acclaimed Green Revolution — has already identified varieties that can germinate at low temperatures (cold tolerance in the early phase) and tolerate the extreme heat during the ensuing May-June months.

"We have planted them in our fields here and also in Sundarbans in West Bengal and Aduthurai in the delta region of Tamil Nadu. The station trials show encouraging results and we plan to release some of them for the All-India Coordinated Project trials from the next spring season. Commercial release could be a distinct possibility over the next three-four years," said Dr S. Nagarajan, Director, IARI.

According to him, the seed cotton yields ranged from 1.5 tonnes per hectare in the northern belt and going up to two tonnes in the Sundarbans area. While this may be below the three tonnes that one can get from the normal kharif cotton, "the new genotypes can mature in just 90-100 days, compared to 145-150 days for the normal varieties and hybrids," he said.

But more importantly, the spring-summer cotton varieties are immune from attack from insect pests (particularly the Helicoverpa armigera or American bollworm) or leaf curl virus. The reason for this is the scotching heat conditions, which militate against pest build-up. "The pests thrive only in conditions of high humidity (say 70 per cent and upwards), whereas the new genotypes grow in the dry heat period when relative humidity is only 30-35 per cent," Dr Nagarajan pointed out.

As a result, there is no need to spray any pesticides. This is unlike the 12-13 sprays that cotton farmers usually resort to, with each spray costing around Rs 700 per hectare. The introduction of Monsanto's genetically- engineered Bt cotton, incorporating a gene from Bacillus thuringiensis, a soil bacteria, that imparts `in-built' resistance to bollworm attacks, is said to have brought down the number of sprays by more than half, though farmers have to still use pesticides against sucking pests such as aphids, jassids, whitefly and thryps.

"In the case of spring-summer cotton, we have not had to spray any pesticides at all. All that the farmer has to ensure is that the crop gets two irrigations, which it requires in the intense summer," Dr Nagarajan said.

He claimed that the fibre quality of the lint extracted from the cotton was of "acceptable" quality and "we see a good future for spring-summer cotton cultivation."

This is particularly so in the North, where the cotton can be planted after harvesting of the ratoon sugarcane crop in February-March. And once the cotton is harvested in June, the farmer can go for a regular kharif crop, like paddy, maize or bajra. "We have also designed the architecture of the new genotypes in a way that the plants are less bushy and without side branches, which gives the farmer the flexibility to grow inter-crops such as moong," Dr Nagarajan added.