The Hindu Business Line : Gains from cotton-jowar rotation system: Study

COTTON scientists contend that diversification of the cotton crop by rotating it with jowar (Sorghum bicolour) for both grain and fodder would have substantial results.

A decade-long study conducted by the Central Institute for Cotton Research (CICR) on a clay-loam soil in this part of the country has indicated that seed cotton and jowar grain yield increased substantially, according to Dr C.S. Pragaraj, Senior Scientist (Agronomy) and Dr T. P. Rajendran, Project Coordinator and Head, CICR.

``We could get an additional seed cotton and jowar grain yield of 4.3 and 77 quintals/hectare respectively, along with 20.5 tonnes/ha of jowar dry straw by following cotton-jowar cropping system,'' Dr Rajendran said.

He said that the productivity increase was confirmed over the years for both - hybrid (Savitha) and variety (Surabhi) of cotton and the normal variety of jowar (CO-26). The higher productivity in cotton-jowar system led to higher returns. Growers were able to get Rs 12,000 for the extra long staple American cotton (Surabhi) along with Rs 18,500 for jowar, thereby making a cumulative return of a little over Rs 30,000 per hectare in this system over that in the cotton-fallow system, he explained.

The researchers further observed that the white fibre, when grown after jowar produced more number of fruiting branches per plant, picked bolls, kappas per plant.

``That is not all. Bolls form early in the season, mature earlier for early marketability and the return is also higher, when compared to mono cropping of cotton. Improvement in the fibre quality traits by way of higher micronaire value was observed,'' Dr Rajendran said.

According to Dr Praharaj, some of the other important aspects of cotton-jowar system were uniform absorption of nutrients from the soil, higher nutrient use efficiency, better weed suppressing ability of jowar on cotton and reduction in pest and diseases.