ANNUAL TROPICAL FRUITS

David S. Seigler Department of Plant Biology University of Illinois Urbana, Illinois USA

Importance Local World-wide Botanical Domestication Changes -some of these crops ancient Technology (especially canning and refrigeration) Cultivation - propagation - Annual Tropical Fruits - Outline

Most Important Cucurbitaceae + squashes + watermelons and cantaloupes + cucumbers Solanaceae + tomatoes + peppers + eggplant

READING CHAPTER 4 IN TEXT.

There are many types of tropical fruits. Some are exotic and not found commonly in temperate regions of the world. Others are well known cultivars such as tomatoes, squash, green peppers and cucumbers. None of them can survive winters such as occur in Illinois. We circumvent this problem by planting them as annual crops. Introduction

Fruits in a Mexican market

Zea mays, as an annual tropical fruit

Phaseolus vulgaris, wax beans

Most of the other types of tropical crops are perennials that cannot be cultivated in temperate zones of the world. pp. 82 ff, pp. 87 ff.

Annual tropical fruit crops mostly belong to two plant families: the Cucurbitaceae and the Solanaceae. Both are represented in both the New and the Old World. Fruits were (are) a major part of the diets of hunter-gatherers. The remains of these plants are found in both the Old and New World.

Changes brought about by domestication. In terms of food value, these fruits contain sugars, starch (some), vitamins and minerals. Fruits are important for variety in human diets.

Technology Until recently, commercial development of fruit crops has mostly occurred in the U.S. Catsup or ketchup played a major role in the development of the tomato. Freezing, canning, and drying were also important. In the U.S., production of fruit crops is largely mechanized. Production of fruits is tied strongly to the socio- economic situation.

Squashes and their relatives Members of the squash family, the Cucurbitaceae, have been eaten in both the Old and New World for thousands of years. Most members of the family are annuals and are vines. The seeds, fruit and blossoms of many are eaten.

Squashes and their relatives Cucurbits are usually grown from seed. The fruits of members of this group are pepos. They are basically inferior fruited berries. See pp. 83 and 85 for a diagram of the fruits etc. Most wild cucurbits are bitter and poisonous.

In the Americas three genera, Lagenaria, Cucurbita, and Sechium, were especially important, whereas in Asia Cucumis and in Africa Citrullis were common.

The taxonomy of true squashes (members of the genus Cucurbita) is very complicated. Most squashes and pumpkins are of one species, Curcubita pepo. There are “fossils” of these fruits in Mexico from 7500 to 9000 years old. Squashes are native to the Americas and were eaten 5-6 thousand years ago. Pumpkins are eaten as a vegetable in most parts of the world.

An assortment of Cucurbita pepo fruits (along with Ted Carey and his wife)

Cucurbita pepo, pumpkins Courtesy Dr. Hans Hummel

Yellow crook neck squash, Cucurbita pepo

Three other cultivated species of the genus Cucurbita are encountered. These species arose in South America and are only known as domesticated plants.

Melons are mostly native to the Old World. Watermelons (Citrullis lanatus) are native to Africa. They were in Europe early and in China by the 11th century. They have lots of water and were often used as a source of water in dry areas.

Watermelons, Citrullis vulgaris The Complete Book of Fruits & Vegetables, F. Bianchini, F. Corbetta, M. Pistola, Crown Publishers, New York, 1973

In some Oriental cultures melons are preserved in salt. Cantaloupes and honey dew melons (Cucumis melo) are also native to Africa, but were known by the Romans. The wild ancestors of these plants are unknown. They are closely related to cucumbers. Cucumbers (Cucumis sativus) are native to southern Asia.

Cucumis melo, cantaloupe

Cucumis sativa, cucumber

More cucumbers

The bottle gourd (Lagenaria siceraria) was found in both the New and Old World. Has long been cultivated in both. Probably drifted across Atlantic from Africa to S. America. The bottle gourd is not only used as a food plant, but is probably most important as a container plant.

Lagenaria siceraria, bottle gourd

More bottle gourds

Chayote (Sechium edule) is a one seeded, Mexican squash-like plant. Luffa and momordica are minor cucurbit crops.

Chayote, Sechium edule

Luffa aegyptiaca, luffa

Bitter melon, Cucurbitaceae

Solanaceous annual plants Most of these are native to the New World, but some Old World species also are cultivated (such as the eggplant).

The tomato, Solanum esculentum This fruit plant is native to Peru or Mexico. Most of the wild relatives of the tomato occur in Peru. The fruit appears to have been domesticated in Mexico. Tomatoes were considered poisonous by some Europeans and by people in the U.S. until the early 1800's.

Solanum (Lycopersicon) esculentum, tomato

Tomato fields near Davis, California

Solanum (Lycopersicon) cheesemanii, a primitive tomato relative

Wild tomatoes are outbreeding perennial herbs. Cherry tomatoes more similar to original types. Selection for self pollination. Humans have also selected for insect, fungal, and viral resistance. Taste has been sacrificed for durability in some commercial tomatoes. Genetically engineered tomatoes.

Physalis ixocarpa, tomatillo

Peppers Fruits of the genus Capsicum are all native to the New World. There are about 5 species of cultivated members of this group. Capsicum annuum was probably domesticated in Mexico. At Tehuacán, pepper seeds 8000 years old have been found. Most were pungent types. Selection for sweet varieties probably arose later.

Capsicum annuum, chile pequin or petín

Capsicum annuum, chile or pepper

Chiles in a Madagascar market

Chiles

Eggplant or aubergine is the only major member of the Solanaceae grown as an annual fruit from the Old World. Probably native to India or Southeast Asia. Came to Europe in the 15th century. Selection for large fruited types. The eggplant, Solanum melongena

Solanum melongena, eggplant or aubergine The Complete Book of Fruits & Vegetables, F. Bianchini, F. Corbetta, M. Pistola, Crown Publishers, New York, 1973

Okra (Malvaceae) is an important tropical annual fruit plant. Okra arose in Africa and was introduced into the Caribbean and the U.S. along with black slaves. The crop appeared early in southwest Asia as well. Okra, Abelmoschus (Hibiscus) esculentus, Malvaceae

Abelmoschus (Hibiscus) esculentus, okra