Sugarcane
This section describes the sugarcane growth cycle and its stages through a practical and dynamic approach. In addition, you will also find a guide detailing the main nutrient deficiencies that can affect your crop and how to identify each of them.
What happens at each stage of sugarcane development?
- Germination: The presence of humidity in soil causes swelling of gemma and primary roots located in the node region. The bud rips the lignified leaves of the gemma, emerges through the germinative pore and develops towards soil surface. At the same time, roots emerge from the stalk piece. Consumption of nutritional reserves of the stalk piece increases.
- Germination and Emergence – Emergence: Occurs 20 to 30 days after planting. The bud is a miniature stem that emerges above soil surface. From then on, it is called the primary stalk. The vegetative apical gemma grows vertically upwards which results in a succession of nodes and internodes and forms the sugarcane stalk. This phase is influenced by quality of plantlet, environment, season and treatment of plantation.
- Germination and Emergence – Initial Rooting: Two to three weeks after emergence, fibrous roots appear at the base of the primary stalk. Their functions include anchoring of the stalk to the ground and absorption of water and nutrients. Together with the stalk piece roots, they form the primordial radicular system of the future sugarcane crown.
- Germination and Emergence – Initial Leafing: Vertical upright growth of the primary stalk commanded by the meristematic activity of the vegetative apical gemma triggers the expansion of the first leaves, thus increasing both the photosynthetic capacity and activity of the young plant. During this phase, a high rate of consumption of nutritional reserves of the stalk piece occurs.
- Germination and Emergence – Start of Tillering: The vegetative apical gemma of the primary stalk has not yet established its absolute dominance which allows lateral gemma located at its base to develop meristemical activity that results in growth of lateral buds towards the soil surface. Since they emerge 20 to 30 days after the emergence of the primary stalk, they are called secondary.
- Tillering – Crown Formation: Tillering process consists of sequential budding of gemma on the primary stalk, which generates the secondary ones; those generate the tertiary ones etc., up to a given limit. Tillering defines the sugarcane crown formation as well as the final
stalk population fit for harvesting. - Tillering – Crown Rooting: Like the primary stalk, all the additional stalks generated by tillering also develop fibrous roots and formation of the crown root system is the result of the root development of each tiller. 90 to 120 days after emergence of the primary stalk, approximately 100% of the crown roots occupy the top 30 cm of the soil. At this stage, the stalk piece roots practically do not exist anymore.
- Tillering – Peak of Tillering: Maximum tillering potential is determined by the competition among shoots for environmental growth
factors (light, water and nutrients). The highest yield is achieved with 10 to 13 tillers per meter. At this stage, the ground is completely covered by plant leaves. Each crown has the maximum number of tillers and apical dominance of older tillers increases. - Tillering – Stalk Growth: After tillering has been completed the stalks that have survived the intense competition among tillers continue to grow and develop, gain height and start to accumulate sucrose at the base internodes. Older leaves start getting yellow and dry.
- Stalk Growth – Vigorous Root Growth: Growth of the root system continue laterally and in depth. Some fibrous roots grow together, forming cord-roots which can reach a depth of more than 1.5 meters. Approximately 85% of the roots occupy the first 35-40 cm of the soil. The first 3 to 4 internodes located at the base of the crown become visible at this stage.
- Stalk Growth – Maximum Foliar Area: Both vigorous vertical plant growth and stalk diameter increase are stimulated high levels of by light, humidity, and temperature. In mid-summer, sugarcane can form up to one node and one internode per week. The foliar area index can reach values up to 7 squire meters per 0.2 squire meters of ground.
- Stalk Growth – Definition of the Final Stalk Population: Stalk growth is the result of a succession of nodes and internodes formed by the apical gemma. When vertical growth ceases, sucrose translocation from leaves to ripe internodes located in the lower third of the stalk increase. Sugarcane may reach a height of more than 3 meters when maximum ve.
- Stalk Growth – Initial Maturation: Initial maturation already start when growth increase after maximum tillering has been reached. Photosynthates that are not used for growth etc. Is translocated to the base internodes of stalks, where it is accumulated and stored.
- Stalk Maturation – Maturation of the Middle: In the middle of the growth period, between the end of summer and the beginning of fall, when the stalks have reached a height of approximately 2 meters, yellowing and consequent drying of leaves of the middle third of the plant can be observed, which shows that sucrose is being deposited in the internodes of that region. The lower third of the stalk shows lignified internodes partially or completely covered with dry leaves.
- Stalk Maturation – Final Maturation: At the end of fall, beginning of winter when the photo period becomes shorter, rain gets irregular and temperatures milder, maturation activities are intensified and growth is reduced. Increased sucrose translocation from leaves to ripe stalk
internodes takes place, where it is stored. - Stalk Maturation – Peak of Tillering: Maximum tillering potential is determined by the competition among shoots for environmental growth
factors (light, water and nutrients). The highest yield is achieved with10 to 13 tillers per meter. At this stage, the ground is completely covered by plant leaves. Each crown has the maximum number of tillers and apical dominance of older tillers increases.
Nutrient Deficiency
MICRONUTRIENTS
- Zinc: A zinc deficiency can cause striped and chlorotic areas on young leaves which may evolve into a slight yellowing of the leaves. Dark green stripes at the side of the main vein. Smaller and thinner stalks. Shorter internodes.
- Manganese: Young leaves show interveinal chlorosis starting at the centre and spreading to the whole length of the leaf. Longitudinal necrosis may split the leaves.
- Boron: Wrinkled, distorted and brittle new leaves. Translucid lesion (“water bags”) among veins. Resembles “pokkah boeng” disease.
- Iron: Interveinal chlorosis along the whole area of young leaves. At the beginning of root formation, the plant may become totally whitish in colour.
- Copper: Plants may have broken and bent down young leaves leaving it with its top bent over. Green spots in chlorotic leaves may also be present and a widening (“sagging”) at the central part of the blades may occur.
- Molybdenum: Small white-yellowish longitudinal chlorotic stripes located at the upper third part of the older leaves.
MACRONUTRIENTS
- Nitrogen: Yellowing of older leaves which dry up prematurely.
Short and thin stalks. Decrease in leaf formation. - Phosphorus: Shorter and narrower leaves than usual. Dark green or bluish green color of older leaves. Shorter and thinner stalks. Reduced or even absent new cane shoots.
- Potassium: A lack of potassium can be identified by older leaf borders bearing a yellow-orange chlorosis. Red spots appear on the upper surface of main veins (restrained to the epidermis). Distorted shoots (“the top in the form of a bunch”) and short internodes can occur.
- Magnesium: Chlorotic spotting of older leaves can develop into necrosis giving a rusty appearance.
- Calcium: Young leaves curl downwards forming “hooks”. As the symptoms become more severe, the end and borders of the interveinal area may dry up. Stalks can be soft and thin.
- Sulfur: Young leaves show uniform chlorosis bearing light purple colour its borders. Leaves are smaller and narrower.