Lowly sweet potato goes high

TO REDUCE the incidence of virus-complex attacking sweet potato, farmers in Tarlac and Albay are using tissue-culture clean planting materials (CPM), the quarterly publication of the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (PCARRD).

"Pathogen-tested, tissue-cultured sweet potato seed pieces are produced in the laboratory and then grown in net houses and multiplier farms for distribution to a wider number of growers," The PCARRD Monitor reported.

Farmers using CPM reportedly saved up to 33 percent on production costs, as "they purchased a small amount of pathogen-tested planting materials and reproduced them in their own multiplication plots using appropriate management practices," said the report.

In addition to the significant increase in yield and income, "the CPM production has proven to be a viable and profitable enterprise giving farmers as much as 325 percent rate of return," it added.

The CPM is just one of the technologies generated from the past sweet potato research and development (R&D) programs done in Central Luzon and Bicol Regions, where sweet potato has provided both short and long-term livelihood.

"(Through these technologies), the sweet potato industry will benefit immensely from a more secure and reliable supply of clean planting materials, thus contributing to an efficient and regular production of sweet potato," wrote Angelito T. Carpio, author of the report.

Aside from increasing the margin of farmers to 4-5 times based on the national average of only five tons per hectare, the generated technologies can sustain production that will meet food, feed, and industrial requirements.

"With these developments, the sweet potato rises to a higher level," Carpio pointed out.

Sweet potato has been touted as a "lowly" crop for its long association as a poor man's crop. It is also used in a discriminatory manner; a loser is someone who is "nangangamote" (Filipino term for lagging behind).

But this connotation is starting to change as sweet potato is now considered a reliable cash crop due to its many uses as food, feed, and raw materials for industrial products. For people and communities affected by calamities such as drought, floods, typhoons, "camote" (as it is commonly known among Filipinos) is a dependable food source to tide them over the crisis.

"Camote is better than palay, mais, cassava, peanut and other crops," a farmer said who considered it as an "all weather crop." "It could pretty survive without fertilizer and even under bad weather conditions," he added. "During typhoons, camote just survives, so we continuously generate income for several months compared to other crops."

What most Filipinos don't know is that sweet potato is one of the most nutritious crops. The Center for Science in the Public Interest, a consumer advocacy group that focuses on nutrition and health, food safety, and alcohol policy, ranked "baked sweet potato number one in nutrition of all vegetables."

The North Atlantic Human Nutrition Research Center on Aging considered sweet potato as one of the world's healthiest foods. The reason: it has the highest amounts of vitamin A among the root vegetables category. It is almost fat-free (0.39 grams).

According to the United State Department of Agriculture, for one medium size sweet potato, a person gets 2.15 grams of protein, 31.56 grams of net carbs, 3.8 grams of dietary fiber, 28.6 milligrams of calcium, 16.9 milligrams of sodium, 265.2 milligrams of potassium, and 29.51 milligrams of vitamin C.

American nutritionists found that sweet potato has "almost twice the recommended daily allowance of vitamin A, 42 percent of the recommendation for vitamin C, and four times the recommended daily allowance for beta carotene."

A cup of cooked sweet potato (about 200 grams) is better than broccoli and cabbage in vitamins A and C, iron, and calcium content. Because nutrients are anti-inflammatory, they help reduce the severity of asthma, osteoarthritis, and rheumatoid arthritis.

Among root crops, sweet potato has the highest vitamin A content. Eating the yellow- or orange flesh color (directly linked to beta-carotene content) can lead to healthy skin and healthy surface linings of the eyes and the respiratory, urinary, and intestinal tracts.

Vitamin A also fights infections very effectively and protects the walls of the arteries and veins against hardening.

Despite the name "sweet," it may be a beneficial food for diabetics, as preliminary studies showed that sweet potato has the lowest glycemic index among root crops. Research shows that sweet potato stabilizes blood glucose levels and enhances the response to insulin.

"It also digests slowly, causing a gradual rise in blood sugar (from complex carbohydrates into glucose)," wrote Arlene May G. Corpus, a therapeutic dietitian at Manila Adventist Medical Center.

Corpus added that sweet potato is also good for those who want to lose weight. "That feeling of fullness helps control food intake," she pointed out.

The roots are not the only edible part of sweet potato but also the leaves and tops. Nutritionists claim the leaves and tops contain high amounts of antioxidants, vitamins, minerals, and dietary fiber.