ARS plant breeder Orville Vogel.
The genes that
sparked the Green Revolution came from unprepossessing wheat plants relegated
to the ranks of agronomic curiosities. But their short, stiff straw and heavy
seed heads caught the eye of ARS agronomist S. Cecil Salmon who was with Gen.
Douglas MacArthur's headquarters in 1946 helping assess Japan's postwar
agricultural problems. Salmon acquired seeds of 16 different
strainsincluding one named Norin No. 10for the World Small Grain
Collection in Beltsville, Md.
Within a year, the Collection processed and
distributed the seeds to various U.S. wheat breeders. Some went to
ARS-Washington State University breeders in Pullman. The Pullman team, led by
ARS plant breeder Orville Vogel, analyzed the seeds' initial progeny for
strengths and weaknesses. Over the next 13 years the scientists made many
hybrid crosses and selections. One of the wheat varieties that came out of
these efforts was the famed short-strawed Gaines.
While hybridization was underway, Norman E.
Borlaug of the International Maize and Wheat Research Centre, Mexico, visited
Pullman and was impressed with the short-stalked wheat's potential. The group
shared germplasm with Borlaug who, in turn, crossed it with Mexico's best
In 1963 Borlaug responded to an urgent
request from the government of India to tour its major wheat-growing regions
and provide breeders with lines containing Norin No. 10 dwarfing genes. The
tall native wheats had encountered an insurmountable yield barrier. When
heavily fertilized with nitrogen, they grew too high, became top-heavy, and
Lemont was the first high-yielding semidwarf rice variety that matured early
and had high milling yields.
semidwarf wheats enabled India to finally launch its Green Revolution. The
combination of new genes, fertilizer, and irrigation spurred wheat production
from 12 million metric tons in 1965 to over 20 million in 1970 and over 37
million last year. Since the new wheats were broadly adapted, Green Revolutions
also took hold in countries sharing similar latitudes, such as Pakistan,
Turkey, and Afghanistan. For his contributions, Borlaug was awarded the Nobel
Arid regions of India also benefited from a
Green Revolution, one based on hybrid pearl millets. But an obstacle to
hybridization had to be overcome first because many grasses, including millets,
self-pollinate. ARS geneticist Glenn Burton altered pearl millet's cytoplasm to
create the cytoplasmic male-sterile plants that made hybrids possible. In 1961,
Burton sent male-sterile millet seeds to India for its breeding programs. By
1965 the Indian scientists developed a new hybrid that out-yielded native
varieties by 88 percent. In that year, India produced 3.5 million tons of
millet. Just 5 years later, millet production climbed to 8 million tons. That
gain in yield accounted for 20 percent of the extra food production in India's
Plant breeders rely on the collection and
preservation of still-extant germplasm. A major effort is underway to save from
extinction not only the seeds of plants now cultivated but also their wild
relatives with rich and irreplaceable genetic qualitiesfrom resistance to
disease and drought to higher yields. A wide variety of genetic material is
essential if breeders are to improve and perpetuate the world's crops.
Two internationally known facilities are
maintained by ARS to help foster genetic diversity. The World Small Grain
Collection, which can be traced to informal origins in the 1870's, serves as a
"working" collection. It collects, maintains, distributes, and
evaluates germplasm to meet the ongoing needs of plant breeders everywhere. At
present, the Collection maintains some 102,000 strains of wheat, barley, oats,
rice, rye, and triticale.
On the other hand, the National Seed Storage
Laboratory (NSSL), Fort Collins, Colo., is a "base" collection. It
maintains, mostly in cold-storage rooms, over 200,000 separate collections of
seed and vegetative stock. Some collections were obtained by expeditions to
remote lands. Although the NSSL's germplasm may duplicate that in working
collections, it releases material only when it is not available elsewhere. Its
prime mission is to perpetually safeguard germplasm, an ultimate gene bank for
the plant breeders working to help feed the world's burgeoning
population.(By Russell P. Kaniuka, Beltsville, Md.)