Sugarcane

Description

Sugarcane, Saccharum officinarum, is a perennial grass in the family Poaceae grown for its stem (cane) which is primarily used to produce sucrose. Sugarcane has a thick, tillering stem which is clearly divided into nodes and internodes. The leaves of the plant grow from the nodes of the stem, arranged in two rows on either side of the stem. The leaves are tubular and blade-like, thicker in the centres than at the margins and encircle the stem. The inflorescence of sugarcane is a terminal panicle which possesses two spikelets and seeds protected by husks (glumes) covered in silky hair. Two flowers are produced on the inflorescence, one sterile and the other bisexual. Sugarcane can reach a height of up to 6 m (3.3 ft) and once harvested, the stalk will regrow allowing the plant to live for between 8 and 12 years. Sugarcane may also be referred to as nobel cane and originates from New Guinea.


Uses

Sugarcane is primarily used for the production of cane sugar (sucrose). One of the biproducts of sugarcane production is bioethanol which can be used as a fuel in place of gasoline. The dried fibre which is left over after the extraction of the sugarcane juice is called bagasse and is used in paper and textile production, as a fuel or as an organic mulch.


Propagation


Basic requirements
Sugarcane grows best in tropical and subtropical regions as the plants require a warm, sunny and moist environment for growth. Plants will grow optimally at temperatures between 26 and 33°C (78.8–91.4°F) where there are no frosts which will damage the plants. Sugarcane can be grown successfully in a variety of soils but will perform optimally in deep, well-draining soils, rich in organic matter with a pH between 5.0 and 8.0. Sugarcane requires an average annual rainfall of between 1800 and 2500 mm per year for adequate growth. If rainfall is too low, plants should be grown with irrigation to maximize yield.

Propagation
Sugarcane is vegetatively propagated by planting part of a mature cane called “setts”. Setts should be cut from carefully selected mature canes. A few days before the cuttings are taken, the end of the canes are removed to break the apical dominance of the cane and promote the breaking of buds. The best cuttings are taken from the upper portions of the cane and should be approximately 40 cm (16 in) in length with 2–3 buds. Sugarcane setts should be planted horizontally or at a 45° angle in furrows 15–30 cm (6–12 in) deep. Once in the ground, the setts should be covered with a thin layer of soil. Setts can be grown in a nursery bed and transplanted to the field or planted directly at the final growing site. The average planting density for sugarcane is 15,000–24,000 cuttings per hectare of land. Normally furrow method of planting is followed. A new method called pit method of planting promises two to three times more yield and more ratoon (up to 10) compared to furrow method.

General care and maintenance
Plantations should be kept free from weeds with weeding being carried out every 3–4 weeks. Weeds can be removed by hand or through the use of machinery or appropriate chemicals. If rainfall is not sufficient to meet the growth requirements of the plants then irrigation must be supplied every 2–4 weeks through furrow or sprinkler irrigation. Soil should be mounded up around the base of the canes 1–2 times during the growing season to promote good root development, aid drainage in heavy soil or prevent lodging in light soils.

Harvesting
Sugarcane is most commonly harvested by hand cutting Stalks should be cut close to the ground with a sharp knife when the canes are fully mature.


Reference


Baucum, L., Rice, R. W. & Muralles, L. (2009). Backyard sugarcane. University of Florida IFAS Extension. Available at: http://edis.ifas.ufl.edu/pdffiles/SC/.... [Accessed 16 April 15]. Free to access.

CABI Crop Protection Compendium. (2012). Saccharum officinarum (sugarcane) datasheet. Available at: http://www.cabi.org/cpc/datasheet/48160. [Accessed 16 April 15]. Paid subscription required.

Verheye, W. (2010). Growth and production of sugarcane. Soils, Plant growth and Production Volume II in Encyclopedia of Life Support Systems (EOLSS), Developed under the Auspices of the UNESCO, Eolss Publishers, Paris, France. Sample available at: http://www.eolss.net/sample-chapters/.... [Accessed 16 April 15]. Free to access.




Common Pests and Diseases

Leaf scald
Xanthomonas albileneans

Symptoms
White "pencil line" extending the entire length of leaf lamina; etiolated leaves; leaf tips drying out resulting in a scalded appearance
Cause
Bacterium
Comments
Disease emergence favored by water stressed plants
Management
The most effective method of preventing the disease is to plant resistant sugarcane varieties; treatment of seed cane with hot water to clean the material prior to planting can help to prevent the disease

Red rot
Colletotrichum falcatum

Symptoms
Yellowing, drying leaves; elongated red lesions on leaf midribs which may develop a straw yellow center; splitting open the stalk lengthwise reveals reddish patches of tissue interrupted by white areas; vascular tissue may also be red
Cause
Fungus
Comments
Disease has eliminated several varieties of sugarcane
Management
Planting resistant varieties of sugar cane is the most effective method of controlling the disease; remove crop debris from the plantation to reduce inoculum levels; rogue diseased plants; harvest crop promptly if growing a susceptible variety; treating seed pieces with hot water prior to planting can reduce the incidence of the disease but foliar fungicide application has proved to be an ineffective method of control

Sugarcane smut disease
Ustilago scitaminea

Symptoms
Stunted growth of sugarcane stools; profuse production of tillers; shortened internodes; stems thin with narrow, erect leaves; black whip-like structure emerging from terminal bud
Cause
Fungus
Comments
Disease transmitted through infected setts and by wind
Management
The disease can be successfully controlled by planting varieties of sugarcane which are resistant to the disease; disease can usually be eliminated from seed pieces by hot water treatment prior to planting; infected plants should be removed

Pineapple disease
Ceratocystis paradoxa

Symptoms
Setts not rooting; central soft portion of set has red discoloration which turns brown-black; cavities in infected internodes; In older canes leaves may be yellowing and plant appears withered; cut stem has a strong smell of pineapple
Cause
Fungus
Comments
Primarily a disease of setts; fungus enters cut ends of stem or through other wounds
Management
The most effective method of managing the disease is through the use of resistant sugarcane varieties; if planting varieties that are susceptible to the disease then plant them in dry, well-draining soils

Eye spot
Helminthosporium sacchari

Symptoms
Small water-soaked spots on leaves; elongated water-soaked spots in shape of an eye; straw colored lesions with reddish brown center develop from water-soaked lesions.
Cause
Fungus
Comments
Disease emergence favored by cloudy weather, high humidity and low night temperatures or wet leaves from precipitation or irrigation.
Management
Disease can be controlled through the application of appropriate foliar fungicides.

Mosaic
Sugarcane mosaic virus (SCMV)
Sorghum mosaic virus (SrMV)
Maize dwarf mosaic (MDMV)
Johnsongrass mosaic virus (JGMV)

Symptoms
Distinct patterns on contrasting greens on leaves i.e. dark green patches surrounded by paler green; reddening of leaves; leaf necrosis
Cause
Viruses
Comments
Symptoms may be caused by 4 different viruses
Management
Plant varieties of sugarcane which are tolerant of viruses