Agriculture Reference
In-Depth Information
Symptoms: leaves becoming lighter in color, eventually exhibiting a light and dark green mosaic. Dark
green leaf parts bulge like blisters. Infections at the time of pod development do not affect yields but
can infect seeds. Remedies: remove plants suspected of being infected, carefully fight aphids.
The bean grower's most feared pest is the bean weevil (
Acanthoscelides obtectus
). This storage pest
was brought to Europe from America via aid shipments after World War II. The insect is brownish
black and is -¼ in. (3-5 mm) long. An infestation can be recognized by small circular holes in the
seed the weevil has eaten out. It cannot handle low temperatures but is happy to eat holes in beans in
the pantry all winter long. Serious cases are usually caused by female weevils laying their eggs direc-
tly on seeds in a pod that has burst, which can happen when still on the plant or during drying, after
harvest but before threshing. Larvae then eat their way into the seeds. Remedies: do not use infested
seed, harvest ripe pods immediately, dry under row cover, close storage containers tightly, store seed
dry, cool (under 54°F [12°C]), and clean. Place infested seed in a deep freezer (−4°F [−20°C]) for two
weeks to kill weevils. Beans must, however, be very dry to avoid being killed by water contained in
the seed expanding into ice.
The more you eat, the more you toot?
Beans are said to be difficult to digest. Perhaps this is why beans are consistently absent from
lists ranking the most popular vegetables. This is unfortunate because protein-rich beans need
only to be properly prepared to make them digestible. Cultures that eat a lot of legumes have
learned how to handle them. One of the most important rules is to never cook legumes with salt
or acid (e.g., vinegar, tomatoes) because this often results in undercooked and thus indigestible
beans. Beans should always be soaked overnight to neutralize their phytic acid content (pour off
the water and use fresh water, with seasonings if you like, to cook). Add salt and acid-containing
vegetables only after the beans have completely cooked. This stops the cooking process, which
helps keep beans intact for any preparation that follows. And when beans are eaten often, bodies
tend to adjust to them in time. Adding summer and winter savory (
Satureja hortensis
and
S.
montana
), with their essential oils, makes beans even more agreeable.
CULTIVATION HISTORY
The wild ancestors of common beans are found in Central and South America,
from Mexico to Costa Rica, Colombia to central Argentina. Common beans were brought to Spain in
the 16th century, and German illustrations from the year 1534 are taken as evidence of its cultivation
in Germany at that time. Like many New World crops, it was initially a curiosity and did not become
widely distributed until the 17th century. In the few centuries of bean cultivation in Europe, a vast
number of diverse regional varieties were developed. Because changes in colors and patterns on beans
are very conspicuous and because these changes are the result of only slight genetic mutations, garden-
ers could easily select for these changes and establish new varieties. Bush beans were bred from pole
beans. One trait that has been intensively selected for since the 1940s is the absence of a string in the
pod. Though these strings can be an annoyance in the kitchen, they are important to the plant, serving
as a supporting framework for the pod.
