Farmers, seed companies, ginners, spinners, agri-machinery manufacturers and the government must join hands in “mission mode” for a quick transition to mechanical picking of cotton, says P G Patil, Director of Mumbai’s Central Institute for Research in Cotton Technology (Circot).
Handpicking is laborious and with workers either not available for the wages that farmers are willing to pay, or when there is a bunching of demand as during harvest time, mechanical picking has become necessary.
But the various players of the cotton economy are taking a segmented view when they should be united in common purpose. Patil cited the Technology Upgradation Fund launched in 2000 as an example of various actors coming together to upgrade the infrastructure of market yards and ginning mills.
Patil spoke after an event organised by the South Asia Biotechnology Centre to acquaint officials and policy makers from eastern and southern Africa with India’s regulatory framework for genetically-modified crops, the gains to the country from the adoption of Bt cotton, and the state of India’s cotton industry.
Mechanical picking will increase the trash content of cotton to about 13-14 percent, up from 3 percent in handpicked cotton. Ginning mills will have to install cylinder pre-cleaners, stick removal machines and saw bend cleaners so that the bales supplied to the yarn industry are of acceptable quality.
In the United States and Australia, all the cotton is machine picked. Machines are also deployed in Uzbekistan and parts of China, Patil said.
Machine picking requires changes in plant agronomy and geometry. The crop must flower at the same time and the plants cannot be bushy. Defoliants will have to be used. These are expensive as they are imported, Patil said.
Pneumatic planters will save seed with uniform row-to-row and plant-to-plant distance. They are faster. Besides, they combine two operations in one as they apply a base dose of fertilizer before dropping seed with a layer of soil in between.
Circot was established in 1924. It brings cotton breeders and the industry together. It mandate begins post-harvest. Patil says the deployment of new age spinning machines has changed the mix of preferred qualities in cotton. Earlier the prized qualities were strength, staple length and micronaire or the air permeability of compressed cotton fibres which is a measure of fineness and maturity. That was when ring spinning was the vogue. Rotor spinners are eight times faster than ring spinners. They require strong fibres. That is the case also with air jet and air vortex spinners, which are respectively 12 and 36 times faster than ring spinners.
Faster spinning machines reduce the cost of producing yarn. They also improve the quality. Air vortex spun yarn is more abrasion resistant and its enables crisp and clear printing. In India, a tenth of the spinning machines are air vortex.
Circot has commissioned a pilot plant at Nagpur to extract all the oil from cotton seed using solvents. Cottonseed has 17-18 percent oil content, of which about 8 percent is retained in oil cake with conventional screw-type mechanical presses. This is wasted on ruminants (milk cattle) which require protein, not fats.
Another process removes gossypol, a compound which harms non-ruminants like poultry and fish.
Circot has also developed a process to extract nano cellulose from cotton. Small quantities of this material when added to newsprint, improves its strength and reduces the share of virgin pulp that has to be added to pulp from old newspapers to increase tear-abilty. Nano cellulose is also added to polyethylene packaging material for the same reason.
Cotton crop waste management is a challenge, Patil said. About 30 million tonnes of this renewable resource is produced every year, but more than three-quarters of it is burnt, causing pollution in the countryside. About 40 plants have come up to manufacture briquettes and pellets which can be used in boilers and commercial kitchens.
(Top photo of P G Patil by Vivian Fernandes)