Sugar Sector: Pakistan’s MY 2010/11 , Sugar production is forecast at 3.77 (MMT). Up 10 % from last year’s estimate of 3.42 MMT, Consumption is forecast at 4.28 MMT and imports at 0.7 MM tons.
- Sugarcane, Saccharum officinarum L.
- an old energy source for human beings and, more recently, a replacement of fossil fuel for motor vehicles,
- First grown in South East Asia and Western India
Around 327 B.C.
- Introduced to Egypt around 647 A.D. and, about one century later, to Spain (755 A.D.).
- Since then, the cultivation of sugarcane was extended to nearly all tropical and sub-tropical regions.
- Portuguese and Spaniards took it to the New World early in the 16th century.
- It was introduced to the United States of America (Louisiana) around 1741.
- 5th largest sugarcane growing area in the world
- Sugar producer 15th biggest global
- Grown One million hectares
- Raw material for 84 sugar mills
- The sugar industry is the country’s second largest agro-industry after textiles
- Besides its edible use
- Alcohol for medicinal purposes
- Ethanol for fuel
- Chip board manufacturing
- Pres mud for OM
- Stem cuttings or sections of the stalks called “setts”
- Each sett contains one or more buds.
- Normally, one bud is present on each node and they alternate between one side of the stalk to the other
- The bud sprouts under favorable conditions and gives rise to a primary stalk
- Stalk is also known as “millable cane”.
- It develops from the bud of seed-cane.
- When seed-cane is planted, each bud may form a primary shoot.
- From this shoot, secondary shoots called “tillers” may form from the underground buds on the primary shoot.
- The leaves are usually attached alternately to the nodes
- The mature sugarcane plant has an average total upper leaf surface of about 0.5 square meter
- The number of green leaves per stalk is around ten, depending on variety and growing conditions..
- Also known as arrow Therefore flowering is also known as “arrowing”. The seeds are extremely small and weigh approximately 250 per gram or 113,500 per pound
- Generally, a day length close to 12.5 hours and night temperatures between 20° to 25°c will induce floral initiation
The Root System – Sett Root
- The first roots formed are sett roots, which emerge from a band of root primordia within 24 hours of planting
- Sett root grow 6-15 days after planting, disappearing by 60-90 days as the shoot root system develops
- By the age of 3 months, sett roots comprise less than 2% of root dry mass.
The Root System – Shoot Root
- Shoot roots are second type of root, which emerge from the base of the new shoot 5-7 days after planting .
- The shoot roots are thicker and fleshier than sett roots and develop in to the main root system of the plant.
- Develops and takes over supply of water and nutrients to the growing shoot.
- Typically, approximately 50% of root biomass occurs in the top 20 cm of soil and 85% in the top 60 cm. The percentage of roots in the 0-30 cm horizon was 48-68%
The Root System – Effects of Soil Compaction
- Reduction in porosity, infiltration rates, and water storage capacity
- Resistance to root penetration and proliferation. Shallow root system makes the plant susceptible to drought during dry spells.
- Reduced nutrient and water uptake
Promotes lodging particularly in unusually wet conditions
Germination and Establishment
- Under field conditions germination starts from 7 to 10 days and usually lasts for about 30-35 days.
- The germination of bud is influenced by the external as well as internal factors.
- The external factors are the soil moisture, soil temperature and aeration.
- The internal factors are the bud health, sett moisture, sett reducing sugar content and nutrient status
- Optimum temperature for sprouting is around 28-30C
- Warm, moist soil ensures rapid germination.
- Germination results in an increased respiration and hence good soil aeration are important.
- Therefore open structured porous soils facilitate better germination.
- Under field conditions, about 60 per cent germination can be considered safe for raising a satisfactory crop.
- Tillering starts from around 40 days after planting and may last up to 120 days.
- Various factors viz., variety, light, temperature, irrigation (soil moisture) and fertilizer practices influence tillering
- Temperature around 30oc is considered optimum for tillering. Temperature below 20 C retards tillering.
- Maximum tiller population reaches around 3-4 month after planting. By about 5-6 month, 50-60 per cent of the shoots establish and a stable population is established.
- Though 6-8 tillers are produced from a bud, ultimately only 1.5 to 2 tillers per bud remains to form canes.
- Ratoon crop gives much higher and early tillering than a plant crop.
- Factor for low tillering
- Spacing & interculture
- Soil fertility
- Balance fertilizer,
- Water availability
- Weed control
- Root & shoot borer
- Termite & rodents
- Disease Management
Grand Growth Phase
- Grand growth phase starts from 4 month after planting and lasts up to 9 month in a 12-month crop.
- Only 40-50% tillers survive by 5 month to form millable cane
- Under favourable conditions stalks grow rapidly almost 4-5 internodes per month.
- Moisture & nutrient stress reduces internodal length. A temperature around 30oc with a humidity of around 80% is most conducive for good growth.
Grand Growth Phase – Threats
- Efficient use of Water and nutrients
- Protection from top & Gurdas pur Borers
- Protection from sucking Insects – like ; pyrella , Whitefly, black bug & Mites
Ripening & Maturation Phase
- Ripening and maturation lasts for about 3 months starting from 9-12 month
- As ripening advances, simple sugars (monosaccharide viz., fructose and glucose) are converted into cane sugar (sucrose, a disaccharide)
- Cane ripening proceeds from bottom to the top
- Ample sunshine, clear skies cool nights and warm days (i.e., more diurnal variation in temperature) and dry weather are highly conducive for ripening.
- Better understanding of what is going on in the plant
- This understanding aids in efficient water and nutrient management
- Control of vegetative growth and manipulation of sugar production to some extent is possible
- Knowledge of phenological growth phases is essential for maximizing cane yields and sugar recovery