February 20, 2012

Sweet sorghum is a C4 plant. The C4 plants represent only about 1% of known angiosperm. Most of them are herbs and weeds of the tropical and subtropical regions, but there are also cultivated species such as corn, sugar cane and sweet sorghum. Despite the fact that consumes additional energy, C4 plants operate more efficiently than C3 since they effectively restrict the photorespiration function.

The additional mechanism available to these plants helps them survive in warm, with plenty of sunshine habitats, where water availability is limited. That is why the sweet sorghum plant stands in soils with limited irrigation.

Although the cultivation of sweet sorghum represents multiple advantages, for a farmer, disadvantages of the particular crop must seriously be considered. Specifically:
• Soil humidity: Depletes soil humidity and soil nutrients leading to degrading its structure.
• Crop residues: The crop residues from cultivation encourage the soil microorganism’s growth that competes with future cultivations for nitrogen (N). Therefore as a culture can follow any other cultivation, does not apply with those who follow the cultivation of sweet sorghum in a crop rotation.
• Allelopathy: Crop residues of certain varieties effect the development of some cultivated crops.

These mean that a proper crop rotation must be design in order to avoid problems to crops following by the sweet sorghum cultivation. The cultivation of sweet sorghum is recommended not to exceed two continuously years.
The choice of leguminous crops as soil improvers such as alfalfa, clover, vetch etc, where they will alternated with linear cultivation of sweet sorghum, so that benefits the last and enhance the fertility and health status of the soil, is an excellent option for the crop rotation.

Source: PhD Thesis: Photosynthetic characteristics of representative plant species of the Mediterranean ecosystem – Sally Alloh Sumbele.
Dimas Kitsios, Associate Professor, School of Agricultural Technology, A.E.T.I, Thessaloniki