New Report Encourages Research on Native African Vegetables

A panel of scientists says African hunger, malnutrition, and rural poverty could be lessened if researchers could improve native vegetables well suited to difficult growing conditions. Africa is home to hundreds of crops tilled in villages, but neglected by scientists.

The U.S. National Research Council, an advisory body to the government, says powerful tools for tackling many of sub-Saharan Africa's basic problems could spring from the ground.

A panel of experts appointed by the council says the region is home to hundreds of indigenous vegetables that have fed Africans for tens of thousands of years. Most of these plants are resilient enough to thrive in poor soil and well suited to the small plots and limited resources of village families. But panel member Calestous Juma of Harvard University says most of these species receive little or no attention from researchers.

"A part of the focus on African agriculture has been on traditional staples like rice, wheat, and others that generally originate from outside the continent,” he said. “Not enough technical attention had been given to crops that originate from the continent itself. That's why we thought the best way to broaden Africa's food base is to focus on identifying crops that originate in Africa."

The National Research Council report entitled "The Lost Crops of Africa" says greater effort to explore the potential of such half-forgotten edibles could lead to enhanced agricultural productivity, more-stable food supplies, and higher incomes in rural areas across the continent.

Juma, a native of Kenya, says the better-known imported crops like rice or corn do not grow well in many areas of Africa, making plants acclimated to the region important.

"And secondly, you have people in many areas of Africa who can't afford to import rice or wheat,” he added. “Therefore, enhancing the productivity of traditional crops will give them the sufficiency in food production that they need."

The report examines the promise of 18 African vegetables, saying they can help feed the continent's growing, often malnourished population and spur development. They were selected from hundreds of ancestral plants to be the most promising. These native vegetables - including amaranth, cowpea, and egusi - are still cherished in many parts of Africa.

But the National Research Council study says that because these local plants are ignored by scientists and policy makers, information about them is often outdated and difficult to find. Despite this neglect, the report emphasizes that the vegetables have merit.

Amaranth, for example, is rich in protein and other nutrients, and grows so fast that the first harvest can sometimes be gathered only three weeks after planting. The bambara bean can grow in very hot, dry climates and produces seeds so nutritionally balanced that the report says some consumers claim they could live on them alone.

This is the second National Research Council report on native African crops. The first in 1996 examined grains. Calestous Juma says it brought significant attention to native African sorghum and millets, which science has improved and which are now exported.

"That report had a significant impact on raising the profile of African crops and demonstrating that the continent had a biological resource base that could be used to expand not just Africans' food base, but also contribute to the global food basket," he noted.

Juma says this is important not only to rural African nutrition and income, but also to the world's ability to endure potential global warming.

"One of the reasons why I think this is significant is because of the recognition of significant ecological change, some of it arising from climate change, that is going to demand that we diversify our food base to be able to provide global security,” he said. “This is where I think Africa could make some contributions."

A third report on native African crops will focus on fruits in a few months.

Source:
VOA News Service
Author: David McAlary
First published: November 1, 2006

Eating Vegetables May Help Slow Memory Loss in the Elderly

New research from the Rush University Medical Center in Chicago indicates your mother was right: eating vegetables is good for you. Epidemiologist Martha Clare Morris found that eating vegetables every day seems to slow mental decline and the development of Alzheimer's disease in old age.

Morris has been looking at the eating habits of thousands of elderly Chicago residents for more than a decade. "Every 3 years we go into their homes and ask them all sorts of questions about their health and lifestyle," she explains. "But also, we administer tests that measure their thinking ability. So that we can look at changes in their thinking ability over time."

Morris had people record the kinds of fruits and vegetables they ate and how often. She found that people who ate more servings of vegetables per day had memories that deteriorated more slowly than those who didn't eat vegetables. "People who consumed two to three vegetable servings per day had a 40 percent reduction in the rate of their decline in their thinking ability, compared to people who consumed around one or no servings of vegetables a day." Eating fruits didn't do as much to preserve thinking ability as eating vegetables.

Morris found that some kinds of vegetables are better than others at preventing memory loss. She asked study participants about green leafy vegetables, yellow vegetables, cruciferous vegetables like broccoli and legumes, or beans. "The more green leafy vegetables they consumed, the slower their rate of decline in thinking ability," she reports. "We also found evidence of association with the other types of vegetables, except for legumes. But the relation was not as strong as for green leafy
vegetables." Morris believes the benefit was derived from those vegetables with especially high levels of vitamin E.

Source:
VOA News Service
Author: Rose Hoban
First published: October 30, 2006

Eating Your Vegetables Helps Fight Stress

Eating vegetables on a regular basis for two weeks helped volunteers in a nutrition study reduce levels of stress-related molecules and boost their blood levels of vitamin C (Journal of Nutrition, volume 134, pages 3021-3025).

Twelve healthy men and women participated in this collaborative study. In addition to other foods, each volunteer ate two daily servings of gazpacho--a chilled soup made with tomatoes, cucumbers, green peppers, onions, garlic and olive oil. By the seventh day of the two-week-long study, volunteers' blood levels of vitamin C had increased by at least 20 percent and remained elevated for the rest of the study.

Levels of four stress molecules decreased significantly. For instance, by the halfway point in the study, uric acid was reduced by 8 to 18 percent. High levels of uric acid can cause gout, a form of arthritis, and may increase risk of cardiovascular disease.

Source:
U.S. Department of Agriculture

How Many Fruits & Vegetables Should You Eat?

Now it's easy to find out with the online fruit and vegetable serving calculator at 5ADay.gov. Just enter your age, gender, and level of physical activity and it'll provide you a suggested number of servings per day.

A growing body of research shows that fruits and vegetables are critical to promoting good health. To get the amount that's recommended, most people need to increase the amount of fruits and vegetables they currently eat every day.

Fruits and vegetables contain essential vitamins, minerals, and fiber that may help protect you from chronic diseases. Compared with people who consume a diet with only small amounts of fruits and vegetables, those who eat more generous amounts as part of a healthful diet are likely to have reduced risk of chronic diseases, including stroke and perhaps other cardiovascular diseases, and certain cancers.

Fruits and veggies come in terrific colors and flavors, but their real beauty lies in what’s inside. Fruits and vegetables are great sources of many vitamins, minerals and other natural substances that may help protect you from chronic diseases.

To get a healthy variety, think color. Eating fruits and vegetables of different colors gives your body a wide range of valuable nutrients, like fiber, folate, potassium, and vitamins A and C. Some examples include green spinach, orange sweet potatoes, black beans, yellow corn, purple plums, red watermelon, or white onions. For more variety, try new fruits and vegetables regularly.

Learn more about the specific nutrients provided by fruits and vegetables with this Nutrient Guide.

Source:
5ADay.gov

Fighting Cancer with Broccoli Seeds

Broccoli seeds may become an economical source of a cancer-fighting compound known as glucoraphanin. Extracting glucoraphanin from the seed for pharmaceutical purposes would be easier, and less expensive, than using broccoli heads.

Scientists at the U.S. Department of Agriculture's Vegetable Laboratory in Charleston, S.C., intend to breed broccoli plants that are prolific producers of seed rich in the compound (HortScience, volume 40, pages 50 to 53).

Already, the researchers have produced relatively high-glucoraphanin broccoli plants, some of which form seed without the help of insect pollinators.

Source:
U.S. Department of Agriculture

Vegetables Can Help Girls Avoid Obesity

Eating veggies — low in calories and an excellent source of fiber — may help preteen girls maintain a healthy weight. That’s indicated in a study by Children’s Nutrition Research Center scientists at Houston, Texas, and their colleagues.

Analysis of food records completed by 114 African-American girls aged 8 to 10 showed that those who reported eating more vegetables had healthier BMI (Body Mass Index) scores (Obesity Research, volume 12 (Suppl.), pages 53S to 63S).

Preteen African-American girls have potentially higher-than-normal obesity rates and may be at a greater risk of heart disease, some cancers, diabetes and stroke when they grow up.

Parents can help their daughters by serving veggies at meals and keeping a variety of low-calorie veggie snacks handy in the refrigerator.

Source:
U.S. Department of Agriculture

Tips for Growing Carrots

Carrots are grown on farms and in family gardens throughout the world. Carrots are easy to raise and easy to harvest. They taste good. And they contain a lot of carotene, which the body changes into vitamin A.

When people think of carrots, they usually picture in their mind a vegetable that is long, thin and orange in color. But carrots come in many different sizes and shapes. And not all carrots are orange.

For example, Paris Market carrots are about five centimeters around. Imperator carrots are thin and about twenty-five centimeters long. And Belgian White carrots are, as their name suggests, white.

For the best results, carrots should be grown in sandy soil that does not hold water for a long time. The soil also should have no rocks.

To prepare your carrot garden, dig up the soil, loosen it and turn it over. Then, mix in some plant material or animal fertilizer.

Weather, soil conditions and age will affect the way carrots taste. Experts say warm days, cool nights and a medium soil temperature are the best conditions for growing carrots that taste great.

Carrots need time to develop their full sugar content. This gives them their taste. If they are harvested too early, they will not have enough sugar. But carrots lose their sweetness if you wait too long to remove them from the ground.

The best way to judge if a carrot is ready to be harvested is by its color. Usually, the brighter the color, the better the taste.

Most people do not know that carrots can be grown during the winter months. If the winter is not cold enough to freeze the ground, you can grow and harvest carrots the same way as during the summer months.

If the ground does freeze in your part of the world, simply cover your carrot garden with a thick layer of leaves or straw. This will prevent the ground from freezing. You can remove the ground cover and harvest the carrots as they are needed.

Carrots are prepared and eaten many different ways. They are cut in thin pieces and added to other vegetables. They are cooked by themselves or added to stews. Or, once they are washed, they are eaten just as they come out of the ground.

Source:
VOA News Service
First published: July 17, 2006

What's the Hottest Hot Pepper?

Varieties of the pepper species Capsicum chinense, such as 'Habanero', are generally the hottest peppers with Scotch Bonnet, Thai, and Cayenne cultivars falling in behind.

Heat intensity of peppers is most commonly measured in Scoville Units, with Sweet Bell Peppers measuring in at zero Scoville Units. For comparison, Habanero peppers range from 100,000 - 300,000+ Scoville Units, while pure capsaicin--the chemical that causes the burning sensation--registers at a whopping 15,000,000 - 16,000,000 Scoville Units!

If you are looking to grow really hot peppers, try to pick those cultivars which register higher on the Scoville scale. Just remember that capsaicin does not dissolve in water, so make sure to keep milk or yogurt nearby to help quench the burn!

Source:
U.S. National Arboretum

Vegetables and Vegetable Gardening

The following posts cover topics related to growing, preserving, preparing, eating, and the nutritional value of vegetables.

• The Black Pearl Pepper: Beauty With a Bite

• Legumes Provide Nutrition for People - and Soil

• Fortified Sweet Potato Provides a Vitamin A Boost to Help Fight Malnutrition

• Growing Vegetables in Shade

• Scientists develop method to grow fruits and vegetables in extreme climates

Tips for Growing Tomatoes

Plant scientists consider them fruit. Most other people think of them as vegetables. Whatever you call tomatoes, there are many different kinds of this popular and healthy food.

Each plant can produce about four to seven kilograms of fruit. Growers can harvest a big crop with little space. Full plants with fruit take about eighty days to grow from seed. Cold weather can damage young plants, so they are often grown inside for four to six weeks.

A tomato plant can grow several thick stems from its base. Only two or three stems should be kept. From the stems come smaller growths called suckers. New suckers that grow between the stems should be removed. There should be a full meter between plants with three stems, a little less for plants with two stems.

There are two general groups of plants. Small tomato plants grow to about one meter. They can be planted rather close together. Some short kinds do not require special care and are often harvested by machines.

Large tomato plants can grow over two meters tall. They also provide larger fruit. These plants need support. One method uses wires run along both sides of a row of plants. The wires help hold the suckers and fruit. The wiring is secured to strong posts on either side of the row. The wires are raised as the plants and fruit grow.

People who grow only a few plants can place wire cages around each one. The cage can be made of wire fence material. The cage helps the plant grow taller and to produce a bigger crop.

Tomatoes often need extra calcium or the fruit may be ruined. Adding lime to the soil can prevent this problem.

Dry conditions may also ruin fruit. Tomatoes need water regularly. The soil should never dry out completely. Dried grass or leaves placed around the plant can help hold water in the soil and control the growth of unwanted plants.

Tomatoes are native to South America. The tomato is a member of the potato family. The leaves of the plant are poisonous, like the leaves of its relatives. Before the middle of the eighteen hundreds, people grew tomatoes only as pretty plants. They called the bright red fruit a "love apple," but would not eat it.

Source:
VOA News Service
Author: Mario Ritter
First published: October 18, 2005

Growing Vegetables in Shade

Farmers often feel they need a lot of sunshine to produce a good crop. But lots of vegetables grow well without much sun.

The Rodale Institute in Pennsylvania published a report about this subject some years ago in its magazine Organic Gardening. The report said many different kinds of foods from blueberries to beans can be grown in the shade.

Some vegetables do need a lot of sun. A vegetable crop expert at the University of Maine advised putting these vegetables where they can get from eight to ten hours of sunlight a day. Tomatoes, melons, squash and peppers are among those that need the most sun.

Plants that produce root crops, such as carrots and beets, need from six to eight hours of sunlight every day. But leafy vegetables, such as lettuce and spinach, need only six hours of sunlight a day.

The Rodale Institute says a garden should be planned carefully especially if you grow different kinds of foods. For example, rows of vegetables should be planted in an east-west direction. That way, as the sun passes overhead, all the plants will receive an equal amount of light. This is especially important when the plants grow to different heights.

Nut trees such as filbert, hazelnut and yellowhorn produce well with only sun in the morning.

Some fruits also do well without a lot of sunlight. In the United States, blueberries, raspberries, and several kinds of pears need only a little sun each day. In Asia, the hardy kiwi grows well in the shade.

Many herbs grow well without much sun. Mint plants, for example, grow well in the shade. So do sage, dill, oregano, borage, chamomile and several kinds of thyme.

The owner of a garden seed company warned against removing shade trees. He cut down all his shade trees to provide more sun for his crops. But then he had to protect his summer lettuce from the heat of the sun by hanging a piece of cloth to provide shade.

Instead of cutting trees, he suggested putting plants that need a lot of sunlight, such as tomatoes, in containers. That way they can be moved as the sun moves.

Internet users can learn more about the Rodale Institute at rodaleinstitute.org.

Source:
VOA News Service
Author: Bob Bowen
First published: March 7, 2006

Fortified Sweet Potato Provides a Vitamin A Boost to Help Fight Malnutrition

The orange-fleshed sweet potato is rich in beta-carotene and helps to eliminate Vitamin A deficiencies in children and adults, a major health concern in Africa. While widely available in the West, this type of potato is not as common in Africa. During the past year, researchers from Kenya and other countries have introduced a new, bio-fortified type of orange-fleshed sweet potato as a way of reducing Vitamin-A deficiencies.

It is orange-fleshed sweet potato day at Lukore Primary School in the Shimba Hills of Kenya's coastal district of Kwale.

A visiting delegation of researchers, government officials and journalists is being treated to a variety of entertainment, all celebrating the virtues of the humble orange-fleshed sweet potato, which is among the highest natural sources of beta-carotene, a precursor to Vitamin A.

In the school's compound is a small plot with rows and rows of orange-fleshed sweet potato plants. Teacher Jackson Nzivo Mwaniki explains that he and the students plant orange sweet potatoes and distribute the vines to parents and other homesteads in the area.

Mwaniki says that his school was chosen last year mainly because of the school uniform that the students wear, and that local residents are happy with the orange sweet potato.

"The shorts and skirts are green, while the shirts are orange," he said. "That is why it [the school] was given first priority. When they chose us, they saw even the area itself, it is a potato-growing area. When it was introduced to this area, they welcomed it very highly. The children were very happy about it, and they even started planting [the sweet potato vines] in their homes."

Lukore Primary School is one of several demonstration sites that researchers have chosen in the district to educate residents about the nutritional value of the orange-fleshed sweet potato and encourage them to include the food in their diets.

According to the World Health Organization, children who suffer from vitamin-A deficiency suffer a dramatically increased risk of death and illness as a consequence. In communities where the deficiency exists, improving vitamin-A status can, on average, reduce young child mortality by 23 percent and measles mortality by 50 percent.

About 45 schools in the Kwale district grow and distribute the vines to households. Roughly 40 percent of households in the district grow the orange-fleshed sweet potato.

Sammy Agili is a sweet potato breeder with the Nairobi office of the International Potato Center. He says that last year his center and the Kenya Agricultural Research Institute introduced eight varieties of orange-fleshed sweet potatoes into Kwale District.

Up until then, people grew and ate predominantly white-fleshed sweet potatoes.

Agili explains that scientists are able to breed into the sweet potato varieties different levels of beta-carotene, sugar, and what is known as dry matter content (DM), which determines how moist or dry the sweet potato is.

"Consumers have different likes," he said. "For example, the children would like those varieties that are low DM and high sugar content. Now when you look at the mothers, their preference is quite different from men also. Men would like those varieties that have high DM, but slightly low sugar content. So we had a range of varieties which we introduced to them to select."

Agili says Kwale District has one of the highest malnutrition and Vitamin-A deficiency rates in Kenya, and that by introducing the different varieties of the orange-fleshed sweet potato, scientists are hoping to improve the area's nutritional situation.

Young children and pregnant and lactating women are most affected by Vitamin-A deficiency, which weakens the immune system and increases the chances of getting measles, malaria, diarrhea and eye conditions. About 70 percent of pre-school children in Kenya are believed to be Vitamin-A deficient, one of the highest rates in Sub-Saharan Africa.

Scientists are able to breed desirable nutritious characteristics into the orange-fleshed sweet potato through a process called "bio-fortification".

Bonnie McClafferty is communications coordinator for Harvest Plus, an U.S.-based international research program that aims to decrease malnutrition by increasing the levels of vitamins and minerals in crops.

McClafferty explains that most poor people cannot afford to purchase a large variety of foods that may contain different vitamins and minerals, nor buy vitamin supplements, nor purchase food that is commercially fortified such as iodized salt.

"The concept of bio-fortification is that you use the powers of modern agricultural plant breeding to breed nutrition directly into the staple foods that poor people eat," she said. "The reason why this is important is that the predominant food of the undernourished are staple foods, up to 70 percent of the diet consists of either wheat or maize or cassava or beans, yet there is not a lot of micronutrients in those staple foods."

The International Potato Center's Agili says researchers will need to do follow-up studies in a year or two to see the impact of the orange-fleshed sweet potato on Kwale District's nutritional situation.

Source:
VOA News Service
Author: Cathy Majtenyi
First published: May 31, 2006

Scientists develop method to grow fruits and vegetables in extreme climates

In a growth chamber in Antarctica, lettuce, tomatoes and cucumbers are being grown alongside flowers. Lane Patterson, of the University of Arizona, runs this chamber at the United States South Pole station and has already spent nine months there. He says all the plants, including the flowers, are edible -- in compliance with an international treaty. He also says South Pole Station personnel, who are isolated at the base for eight months a year, appreciate the chamber for more than just the food.

"Coming to a place that's green, pleasant, warm and has high humidity is also something that is very beneficial to the crew there at the South Pole," he says

Mr. Patterson says keeping the chamber that way depends on a lot of lights. The 1,000 watt bulbs are kept in special, water-cooled jackets that prevent them from burning the plants, and keep the lights cool enough to touch.

"This is a proven technology. It is relatively inexpensive and it is rugged,” says Mr. Patterson. “At the South Pole there is no re-supply during the winter, so if bulbs burn out faster than what you thought, then there is no re-supply, no vegetables."

Lane Patterson is due to return to Antarctica soon, to refine the system, which scientists hope could someday be used on the Moon or Mars.

Source:
VOA News Service
Author: Amy Katz
First published: January 10, 2006