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Interest in potentially new crops is currently high-news of plant sources for such items as processed food protein, rubber, fuel, and pulp appears almost daily. Whereas 25 or 30 major crop plants meet our needs for food, fiber, or shelter, even a partial list of known useful plants cultivated by man in the past, would run over 20 to 30 thousand names.

Wild wheats still flourish over a small corner of southeastern Europe and much of the Mideast. They are found from the Balkan Peninsula to Transcaucasia and southward in both arcs of the Fertile Crescent, to the Persian Gulf on the east and the Dead Sea on the west. From these wheats Stone Age man domesticated the types that fed emerging Near Eastern civilizations and, in time, gave rise to our durum and bread wheats.

A narrow strip of the western coastline has furnished California with a rare, unique source of wild plant germ-plasm that has helped the strawberry industry to flourish.

The pungent-red pepper was one of the first plants seen by Columbus on his urival in the New World—a new spice which is now grown in the tropics and subtropics around the world. Imagine the surprise and distress on Columbus' face when he bit into the fruit which was “…violently strong and growing on a shrub no bigger than a goosberry bush.” He had found a plant which had long been used by native peoples of the New World and which was cultivated from northern Mexico to southern South Amaria. The quantities of these pungent fruits consumed by the Indians was unbelievable to the Europeans. Many kind had specific uses and certain varieties were so esteemed that they were reserved for the exclusive use of the ruling classes.

In the first half of this century safflower (Carthamus tinctorius) was grown for oil over a wide area of south central India and, to a limited extent, in western Turkey and Upper Egypt. It was grown on a very small scale for the flowers which served as a source of dye to color foods (the poor mans saffron) over a much wider area of the Middle East. Culture for the flowers was disappearing and, under U.S. assistance programs, introduced safflower germplasm was, in some cases, replacing local types. Fortunately collections of local types began in 1958, before it was too late. There are now about 1,500 entries in the safflower collection of the US. Department of Agriculture.

Few people envision California as a “cotton state.” But for most recent years it has held second place (to Texas) in national production and three years ago was first.

Sunflowers (Helianthus annuus L.) are presently grown on a limited acreage in California, but because of their potential we maintain two germplasm collections: (1) domestic types, of both oilseed and confectionary varieties, and (2) wild species, including H. annuus and 25 other species.

Considerable effort has been made over the years to systematically collect, preserve, and identify the germplasm resources of barley on a worldwide basis. One of the largest collections of barley germplasm has been assembled and maintained by the United States Department of Agriculture at Beltsville, Maryland. This collection, numbering approximately 20,000 entries, is available to scientists throughout the world and has been utilized extensively in the continuing improvement and protection of barley cultivars for California. Researchers at the University of California at Davis have not only utilized this collection in their breeding programs but have contributed substantially to the identification of important sources of germplasm for specific plant characteristics, primarily in the area of disease resistance.

The almond is a uniquely California crop and 99 percent of U.S. product occurs here. Germplasm materials in California originated as chance seedlings from seeds and plants imported from the Mediterranean region between 1850 and 1900. The basic cultivars Nonpareil, Texas Prolific (now known as Mission), Ne Plus Ultra, Peerless, Drake, and I.X.L. originated with this material.

Cut flowers are a sizeable commodity in California. Last year, according to the U.S. Department of Agriculture Crop Reporting Board, the three major greenhouse species alone—carnations, chrysanthemums, and roses—were valued in excess of $83 million at the nursery. In addition, about 50 other species, including field-grown, accounted for perhaps another $50 million. It appears that most of these flowers were initially selected for commercial culture for reasons other than flower productivity.

In the 1930s the stem nematode, Ditylenchw dipsaci was causing heavy losses in alfalfa stands, particularly in the Antelope Valley area of Los Angeles County. Again, material from Turkistan was found to have some plants which were resistant, and a new variety named Lahontan was developed and released. Subsequently it was found that an introduction from Iran with less winter dormancy had plants with a high level of stem nematode resistance, and this variety is being used in breeding work at Davis.

Nearly all cultivated grape varieties, of which several thousand are grown commercially, derive their excellence in fruit quality from the Vitis vinifera grape. Although long considered a single species native to the temperate zone of Middle Asia, the vinifera is more of a complex of several ecospecies. Outlying relict populations also exist in some of the principal river basins of the Mediterranean area, and of the Rhine, Mostar, and Danube valleys. However, the role of these populations in the origin of cultivated forms is questionable.

University of California and U.S. Department of Agriculture scientists have been conducting a wheat breeding program at Davis since the 1920s. In the early years, germplasm resources came from the old California cultivars, with their characteristic white grain. The situation changed dramatically in 1961 when a previously unimportant disease, stripe rust (Puccinia striiformis), devastated much of the crop in the Sacramento Valley. During that year, varieties from Mexico proved resistant and replaced the original cultivars in California commercial production.

Rice, a crop native to the Orient, was introduced to the eastern United States as early as 1609. The earliest recorded experimental plantings in California were near Butte Creek in the Sacramento Valley in 1909. By 1912, rice was established here as a commercial crop. The most successful early introductions generally were from similar high-latitude areas of the Far East. For example, the variety Caloro was first selected in 1913 from the Japanese variety Early Watari-bune, and Colusa was selected in 1911 from the variety Chinese (from China via Italy).

Forests with commercial potential for wood products cover 17 percent of California (17 million acres). Nearly north coast and in the north coast ranges, two-thirds of this acreage is along the while over 20 percent is in the Sierra Nevada. In contrast to its field crops, all of California's commercial timber species are native. Coniferous species comprise 99 percent of the growing stock volume.

The tomato is a classic example of a cultivated plant that has been markedly improved by hybridization with primitive cultivars and related wild species. During the past 40 years such crosses have transferred genes for many useful traits. Resistance to Fusarium and Verticillium wilts and to nematodes was bred from these sources. High soluble solids content of fruits and resistance to other diseases are currently being transferred to improved cultivars.

The first European settlers found California rich in natural resources including grazing land that established the agricultural industry. The grazing of domestic animals began with the arrival of the first Spanish colonists in 1769 and the industry grew with the spread of missions in the state. Livestock ranching has continued to be the most wide-spread agricultural activity. However, as farming has made inroads into the valleys and foothills, more than 100 million acres in the pastoral use have shifted from these areas to the remaining grasslands and woodland communities.

The University of California's citrus variety collection was initiated with the establishment of the Citrus Experiment Station (CES) in 1910, at what is now UC's Riverside Campus (UCR). The collection, numbering more than 1200 accessions from throughout the world, has been used extensively to solve citrus disease problems, improve varieties, and congregate and preserve valuable germplasm resources.