By Sosimo Ma. Pablico, Ph.D., Agriculture Magazine August 2006 via SEAMEO SEARCA

The Philippines may as well also consider sweet sorghum as sustainable source of ethanol, as it can now use the knowledge and science developed in India as a solid basis for full-scale commercialization. Ethanol can be blended with petrol to reduce dependence on fossil fuels, and minimize carbon and monoxide emission in motor vehicles.

Ethanol is a "clean burning fuel" with high octane rating. Thus, there are claims that existing automobile engines can be operated with petrol blended with ethanol without any need for engine modification.

At present, the country imports $3.9 billion worth of crude oil and petroleum products a year.

Dr. William D. Dar, the Filipino director general of the International Center for Research in the Semi-Arid Tropics [ICRISAT] in India, said that since the biofuels initiative in the country today is very important for our survival, "we should be looking for the variety of major sources of bio-fuels that we can develop and sustain," Dar said in an email to this writer.

"We need to promote commercialize sweet sorghum for ethanol production," he said, as sweet sorghum offers the best alternative source of raw material.

The production of ethanol from sweet sorghum will not only save enormous amount of foreign exchange but also reduce pollution and provide cleaner air for a constantly growing population.

In a paper sent to this writer, Dar said sweet sorghum is best suited for ethanol production because of its higher sugar content compared to other sources like sugarcane and Jatropha.

In addition, unlike sugarcane, sweet sorghum is propagated through the use of seeds and suitable for mechanized crop production. Likewise, there is practically no wastage in sweet sorghum since every part is used starting from sugar extraction, fuel for boilers and animal feed.

Besides the stalks for ethanol production, sweet sorghum varieties produce grain yields of 2 to 2.5 t/ha, which can be used as food/feed or for potable alcohol preparation. Compared with sugarcane whose sugar content is only 10 to 20 percent, that of sweet sorghum is 15 to 23 percent.

Further, silage from sweet sorghum has higher biological value than bagasse from sugarcane when used as feed for animals, as it is rich in micronutrients and minerals.

Aside from its multiple uses as food, feed, forage and source of ethanol, sorghum seeds can be harvested in 100 days. Moreover, its ratoon also matures in 85 to 95 days after cutting. In contrast, it takes almost a year for a sugarcane crop to mature.

Furthermore, it is cheaper to produce sweet sorghum than sugarcane. In India, for instance, the cost of cultivating sweet sorghum is about one-third that of sugarcane.

At the Mariano Marcos State University, which is headed by Dr. Miriam E. Pascua, five sweet sorghum varieties developed at ICRISAT have been found to mature in 100 days, according to Dr. Heraldo L. Layaoen, MMSU vice president for administration who is also the coordinator of an MMSU-ICRISAT sorghum project.

Seeds of sweet sorghum varieties NTJ 2, SPV 422, ICSV 700, ICSV 93046 and ICSR 93034 are now available at MMSU. Results of the production trials showed that their grain yields in the seed crop ranged from 3.28 to 3.62 t/ha, while that in the first ratoon varied from 3.92 to 4.40 t/ha.

Similarly, the stalk yields of these varieties in the seed crop ranged from 43.48 to 55.60 t/ha, while the first ratoon produced 45.5 to 57.65 t/ha. Although variety SPV 422 consistently produced the lowest grain yield, it also consistently produced the highest stalk yield and the highest sugar content [19 percent]. Please see accompanying table.