May 07, 2007
Improving sugar recovery
By Bilal Hassan
THE sugar content recovery of sugarcane cultivars grown in the country varies from 7.5 to 8 per cent, far away from international standards. Keeping this in view, the Pakistan Sugar Mills Association has put forward a proposal to develop local cane varieties with better yield and sugar contents. The association has also recommended importing varieties and technology from Australia to bring cane yield at par with the international levels.
Importantly, the low yields of sugarcane variety SPF-238 has played havoc with sugarcane in most areas of Punjab, except southern district of Rahim Yar Khan and Rajanpur. So SPF-238 needs to be abandoned by growers of upper and central Punjab. For that stringent efforts are required to bring sugar industry out of crisis. On one hand, it requires to trigger research system to come up with varieties of high sugar contents and yield. At the same time, management of sugarcane crop is essential to enhance per acre yield.
At present, average production of sugarcane in Pakistan is 22,000 kg per acre which is below the potential. Agronomic factors like preparatory tillage, bed preparation, planting techniques, planting time, availability of irrigation water, application of fertilisers, management of ratoon crop, harvesting time, type of cultivars, plant protection measures significantly affect cane yield per hectare. Yield of sugarcane and sugar recovery in main sugarcane growing countries of the world is given in the table for comparison purpose.
It is appropriate to discuss various agronomic factors contributing to low cane yield. Preparatory tillage includes initial ploughing with a tractor-mounted mouldboard plough which is considered essential and should be done extensively. The use of a subsoiler after every four or five years improves the soil considerably by breaking the hardpan.
Sugarcane is a deep-rooted plant that requires a well-worked and fully pulverised seedbed. Fine seedbed can be prepared by ploughing with a furrow-turning plough to a depth of about 20-25 cm particularly when soil is clayey. Six to eight subsequent ploughings followed by planking are enough to achieve a good pulverised seedbed free of clods and weeds. Therefore, use of seedbed preparatory implements is extensive. It is important that seed bed preparation with adequate moisture gives boost to tillering, essential to obtain optimum number of plants per acre.
Timely sown crop yields more tillers because of soothing effect of temperature. Day length is also an important factor associated with vegetative and reproductive growth..Two planting season of sugarcane crop are fall and spring. Planting is done on both dry and wet seedbed depending upon the soil condition, water availability, planting time, etc. Double-cut sets are placed end to end in furrows at a depth of 8-12 cm and covered with 5-6 cm soil. In the dry method, immediate irrigation is essential, with subsequent irrigations at short intervals.
Adequate and healthy seed ensures optimum plant population, a factor significantly affecting cane production. Optimum plant population depends on appropriate seed rate and spacing but the growers often ignored them, which is the key factor in lowering sugarcane production. The seed rate and spacing between rows differ with variety. Eight to nine tones of stripped cane per hectare for thick varieties, and six to seven tones for medium to thin varieties is sufficient to produce a desired plant population of about 0.15 million canes/ha.
Sugarcane is a perennial crop and water requirements on an average varies from 120-160 centimetres for the spring crop and 200-250 centimetres for the autumn crop depending upon planting season, the fertility of the soil, and the variety of cane. Autumn planting requires a higher quantity of water than spring planting. During the dry period, sufficient water should be applied at relatively short intervals to avoid moisture stress.
Toward the end of the growing season, the length of the intervals should be increased, with irrigation ceasing 25-30 days before harvest to induce normal maturity. Total expenses on irrigation are, therefore, highest.
Soil fertility and productivity significantly affect cane production. The nutrient requirements of sugarcane, especially NPK, are higher than those of any other commercial crop because of its high dry matter production per unit area. Moreover, it is an exhaustive crops like wheat, rice, maize etc. that uptake huge amount of nutrients. It requires macro-as well as micro nutrients. Each fertiliser elements plays its role in the development and production of a normal cane crop. Nitrogen is essential for plant growth; phosphorus for developing roots, influencing the ripening process, and purifying the juice; and potassium for promoting cell activity and growth, increasing resistance to infection and lodging, and improving sucrose content.
Sugarcane is heavily attacked by insects, pests and diseases at various stages of growth. Even sugarcane can be damaged from the first stage of growth by insects. Termites, pink sugarcane mealy bug, sugarcane borer, top borer, root borer, armyworm, Indian sugarcane leafhopper, sugarcane white fly, white woolly aphid and field cricket. Insects/pest cause damage to roots, foliage, bud and shoot. Non-control of insects/pests, therefore, leads to significant reduction in cane yield. The extent of damage varies depending upon crop cultivar and management practices.
http://www.dawn.com/2007/05/07/ebr4.htm
Improving sugar recovery
By Bilal Hassan
THE sugar content recovery of sugarcane cultivars grown in the country varies from 7.5 to 8 per cent, far away from international standards. Keeping this in view, the Pakistan Sugar Mills Association has put forward a proposal to develop local cane varieties with better yield and sugar contents. The association has also recommended importing varieties and technology from Australia to bring cane yield at par with the international levels.
Importantly, the low yields of sugarcane variety SPF-238 has played havoc with sugarcane in most areas of Punjab, except southern district of Rahim Yar Khan and Rajanpur. So SPF-238 needs to be abandoned by growers of upper and central Punjab. For that stringent efforts are required to bring sugar industry out of crisis. On one hand, it requires to trigger research system to come up with varieties of high sugar contents and yield. At the same time, management of sugarcane crop is essential to enhance per acre yield.
At present, average production of sugarcane in Pakistan is 22,000 kg per acre which is below the potential. Agronomic factors like preparatory tillage, bed preparation, planting techniques, planting time, availability of irrigation water, application of fertilisers, management of ratoon crop, harvesting time, type of cultivars, plant protection measures significantly affect cane yield per hectare. Yield of sugarcane and sugar recovery in main sugarcane growing countries of the world is given in the table for comparison purpose.
It is appropriate to discuss various agronomic factors contributing to low cane yield. Preparatory tillage includes initial ploughing with a tractor-mounted mouldboard plough which is considered essential and should be done extensively. The use of a subsoiler after every four or five years improves the soil considerably by breaking the hardpan.
Sugarcane is a deep-rooted plant that requires a well-worked and fully pulverised seedbed. Fine seedbed can be prepared by ploughing with a furrow-turning plough to a depth of about 20-25 cm particularly when soil is clayey. Six to eight subsequent ploughings followed by planking are enough to achieve a good pulverised seedbed free of clods and weeds. Therefore, use of seedbed preparatory implements is extensive. It is important that seed bed preparation with adequate moisture gives boost to tillering, essential to obtain optimum number of plants per acre.
Timely sown crop yields more tillers because of soothing effect of temperature. Day length is also an important factor associated with vegetative and reproductive growth..Two planting season of sugarcane crop are fall and spring. Planting is done on both dry and wet seedbed depending upon the soil condition, water availability, planting time, etc. Double-cut sets are placed end to end in furrows at a depth of 8-12 cm and covered with 5-6 cm soil. In the dry method, immediate irrigation is essential, with subsequent irrigations at short intervals.
Adequate and healthy seed ensures optimum plant population, a factor significantly affecting cane production. Optimum plant population depends on appropriate seed rate and spacing but the growers often ignored them, which is the key factor in lowering sugarcane production. The seed rate and spacing between rows differ with variety. Eight to nine tones of stripped cane per hectare for thick varieties, and six to seven tones for medium to thin varieties is sufficient to produce a desired plant population of about 0.15 million canes/ha.
Sugarcane is a perennial crop and water requirements on an average varies from 120-160 centimetres for the spring crop and 200-250 centimetres for the autumn crop depending upon planting season, the fertility of the soil, and the variety of cane. Autumn planting requires a higher quantity of water than spring planting. During the dry period, sufficient water should be applied at relatively short intervals to avoid moisture stress.
Toward the end of the growing season, the length of the intervals should be increased, with irrigation ceasing 25-30 days before harvest to induce normal maturity. Total expenses on irrigation are, therefore, highest.
Soil fertility and productivity significantly affect cane production. The nutrient requirements of sugarcane, especially NPK, are higher than those of any other commercial crop because of its high dry matter production per unit area. Moreover, it is an exhaustive crops like wheat, rice, maize etc. that uptake huge amount of nutrients. It requires macro-as well as micro nutrients. Each fertiliser elements plays its role in the development and production of a normal cane crop. Nitrogen is essential for plant growth; phosphorus for developing roots, influencing the ripening process, and purifying the juice; and potassium for promoting cell activity and growth, increasing resistance to infection and lodging, and improving sucrose content.
Sugarcane is heavily attacked by insects, pests and diseases at various stages of growth. Even sugarcane can be damaged from the first stage of growth by insects. Termites, pink sugarcane mealy bug, sugarcane borer, top borer, root borer, armyworm, Indian sugarcane leafhopper, sugarcane white fly, white woolly aphid and field cricket. Insects/pest cause damage to roots, foliage, bud and shoot. Non-control of insects/pests, therefore, leads to significant reduction in cane yield. The extent of damage varies depending upon crop cultivar and management practices.
http://www.dawn.com/2007/05/07/ebr4.htm