Sugarcane
Sugarcane, in the beginning originating from the Saccharum officinarum species, comes from the Asian continent, and has been planted their sins and social times. In Brazil, the plant was brought by the Portuguese, at the beginning of the sixteenth century. It prospered mainly in the Brazilian Northeast, being responsible for converting it into the best creator and exporter of sugar in this period, with extended Intel the seventeenth century.
Today, however, it is in the interior of São Paulo state that the greater part of sugarcane fields are located. And sugar is not its main product, since currently, alcohol especially ethanol, extracted from this plant, is what stands out most economically, since, as an alternative fuel, it equally contributes to sustainable development.
After planting, sugarcane crops allow three two eight consecutive harvest, depending on various factors: varieties, soil management, water and climate. This crop receives the name plant-cane, in its first cut, ratoon, or second leaf, in the second; and re-ratoon, or later or in the rest of the cuts until the final harvest, thus completing the cycle of planted cane, when restoration of the sugarcane field is carried out.
With the end of the cane cycle, farmers can choose to immediately renew their planting or proceed by rotating with other crops. This choice will depend on their goal, which in short can be to improve the physical-chemical conditions or increase income.
The most common system is to use crops in rotation or reform involving operations like: removal of the cane (between September and October), destruction of the cane roots, liming, soil preparation, planting of annual crop, harvest (between February and March) and new planting of sugarcane, shortly after.
During renovation of the sugarcane field, normally farmers use plants known as green fertilizers, with the goal of obtaining a surface cover and maintaining or improving the soil‘s physical, chemical and biological properties, including at a depth.
The cultivation of short cycle species in areas of sugarcane renovation provides farmers with a series of agronomic, economic, political and social advantages. Several advantages of rotating crops in sugarcane farming are:
- Savings in renovation the sugarcane fields;
- Soil conservation, due to maintaining coverage in times of high rain;
- Control of weeds during the annual sugarcane cultivation;
- Indirect combat against diseases like diatrea and elasmo, which are hosted in weeds;
- Increased sugarcane productivity and food production.
In areas of sugarcane field renovation, one can choose to plant legumes, above all crotalaria juncea, soybeans, and peanuts, the choice depending on location to be used for planting, slope, predisposition to soil pests and availability of machinery and implements to introduce the activity.
Crotalaria juncea
As a green fertilizer, crotalaria juncea presents the following advantages:
- Erosion control;
- Reduced silting of planting furrows, facilitating germination;
- Recycling of percolated nutrients;
- Does away with the need of nitrogen based fertilizers in planting;
- Reduced incidence of weeds;
- Increased productivity.
Sources:
Agência Embrapa de Informação Tecnológica. Authors: Antonio Dias Santiago; Raffaella Rossetto.
Infoescola. Author: Ana Lucia Santana.