Exploration ior ZoysiagrassIn Eastern Asiaby J. JACK MURRAY and M. C. ENGELKE*

GENETIC DIVERSITY within aplant species is the hammer andnails needed by plant breeders

to develop superior varieties. Consider-able effort has been taken to collect andconserve genetically diverse germplasmof major crop species, such as wheat,barley, corn, soybeans, and forage crops.By comparison, little effort has beenmade to collect and conserve germplasmof turfgrass species. With a few andnotable exceptions, representation of

*Research Agronomist, USDA, Field CropsLaboratory, Beltsville Agricultural ResearchCenter - West, Beltsville, MD 20705, andAssociate Professor, Turfgrass Breedingand Genetics, Texas A&M University, Dallas.

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primitive and wild germplasm of turf-grass species in existing collections isscant, rarely representative of the geneticdiversity that exists in the geographicalcenter of origin of the species, and wasprobably collected by someone notfamiliar with desirable turf-type charac-teristics. Thus, the germplasm neededby breeders attempting to developimproved turfgrass varieties for thefuture is not readily available.

Interest in and concern about thecurrent and future availability of geneticresources have increased in recent years.The reasons for this are many. Theemphasis by turfgrass breeders todayis focused on developing improvedvarieties with lower maintenance require-ments in terms of labor and energysavings, and adaptability to adverse

environmental conditions. This shift inbreeding objectives, requiring geneticallydifferent germplasm, and the realizationthat many of the centers of germplasmdiversity that have remained undisturbedfor hundreds of thousands of years arerapidly disappearing because of popu-lation increase and land development.This has led to the general realizationof the inadequacy of present turfgrassgermplasm as well as the urgency tobroaden its genetic variability by thecollection and preservation of diversegermplasm.

The Research Advisory Committeeofthe USGA's Green Section recognizedthe need to increase the germplasmavailable for turfgrass breeding projects.They have recently been instrumental inproviding funds for two exploration trips:

A GREEN SECTIONRESEARCH PROJECT

one to collect bermudagrass (Cynodonspp.) in South Africa (see article inJuly-August, 1982, GREEN SECTIONRECORD)and one to collect zoysiagrass(Zoysia spp.) in Southeast Asia. Webelieve these are the first explorationsmade specifically to collect germplasmof turfgrass species. Hopefully, theResearch Committee's initiative can beexpanded to a cooperative global net-work with international participationfor germplasm collection and conser-vation of the maj or species.

The authors submitted a proposal tothe United States Golf Association andto the United States Department ofAgriculture in 1981 for joint fundingof an exploration of zoysiagrass germ-plasm to the Orient, where the specieshas evolved, i.e., its center of origin.Funding was approved by both organi-zations for travel in the spring of 1982.The trip began on May 14 and included

about two weeks in each of four coun-tries - Japan, South Korea, Taiwan,and the Philippines.

Samples were collected from as farnorth as 43°N latitude (equivalent toMilwaukee, Wisconsin) to as far southas 9°N latitude (equal to Panama).Samples of each of the three recognizedspecies of zoysiagrass were collected,i.e., Z. japonica, Z. rnatrella, and Z.ten uifo lia. Samples were also collectedof two species identified in the Orient asZ. rnacrostaycha and Z. sinica. Samplesof other grass species were collected,including bermudagrass, Kentuckybluegrass, bentgrass and fescues. Theentire collection consisted of 421samples from Japan, 261 from Korea,53 from Taiwan, and 62 from thePhilippines. All samples collected wereshipped to the United States and arepresently growing under greenhouseconditions.

PRIMARY EMPHASIS during thetrip was to collect as much genetically

diverse zoysiagrass germplasm as possibiefrom diverse environmental niches.Many of the samples collected wereexisting in the wild with no fertilizationor supplemental irrigation, under heavytraffic, close constant grazing, or modestto heavy shade. Samples were obtained

from under seven inches of snow withgood color, from salt beds, cattle andhorse pastures, volcano craters, parks,cemeteries, and golf courses. Consider-able differences were observed amongsamples in color, growth and floweringhabit, leaf texture, disease resistance,and adaptability to low-maintenanceenvironments.

Zoysiagrass grows wild throughoutJapan. It was found as far north as Otura,on the northern coast of Hokkaido, thenorthernmost part of our trip (43°Nlatitude). Samples were collected fromgolf course fairways that had been over-seeded with Kentucky bluegrass butremained about 50 percent native zoysia-grass. Along the southern coast ofHokkaido, samples were collected fromunimproved range land being grazedby cattle, and along the seacoast. Thesoils in this area are coarse volcanic ashand droughty. The growing days areshort, due to the northern latitude andfrequent morning fog.

In the Hatochimatia mountains, incentral Japan, we experienced sub-freezing temperatures and approximatelyseven inches of snow at elevations of3,000 to 4,000 feet. We randomly sampledzoysiagrass pastures at ISO-foot intervals,as this area was totally under snow.Many samples appeared dormant, but a

(Left) Collecting on Taiwan.

MAY/JUNE 1983 9

few showed definite green color. Con-siderable winter hardiness, droughttolerance, and fall color differencesshould exist among these samples.

In Tokyo we visited the grounds ofthe Imperial Palace, which have been inzoysiagrass since the 14th century.Numerous ecotypes were found havingdifferences in foliar color and floweringhabit. On the northwestern coast ofHonshu, the main island of Japan,samples of zoysiagrass, bentgrass andtall fescue were gathered from water'sedge to an elevation of approximately75 feet. These plants experience con-siderable salt spray from the sea. On thesouthern island of Kyushu, collectionswere made in Cape Toi and from Mt.Aso. Cape Toi is a national wild horserefuge. The horses graze on naturalzoysiagrass range. When zoysiagrassseed is eaten and passes through thedigestive system of the horse, the seedwill germinate. Zoysiagrass is one ofthe first species to establish itself onvolcanoes following eruption. In thecrater of Mt. Aso, considerable varia-bility was observed in time of floweringand floral characteristics.

Golf is a very popular sport in Japan.Today, there are 1,400 golf courses,with 20 new ones costing $20 millioneach being opened each year. Cpursesare open year-round, except those innorthern Japan, which open from Aprilto early November because of severecold and heavy snowfall. About 60percent of the courses are using zoysia-grass greens and 90 percent zoysiagrassfairways and roughs. Specific zoysia-grass selections are being used on manygolf courses. Selections are classifiedby their morphological characteristicsor by names associated with area ofproduction or origin. For example, theTokyo selection is very popular for useon greens in the central region. Thereare no cultivars as we know them in theUnited States. This situation causesconsiderable confusion in classification.

WE VISITED 13 golf courses inJapan, several with members or

staff of the Konsai Golf Union (KGU).The KGU is similar to the USGA GreenSection in the United States. Numeroussamples were taken from golf courses,greens, fairways and roughs. Some ofthese have been in cultivation for decadesand express considerable differencesin response to disease and insects,moisture stress, and management prac-

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Emerald zoysiagrass on u.s. Military Cemetery. Manila. Philippines.

Zoysiagrass seedheads in a golf course rough. Japan.

Collecting zoysiagrass along a salt basin in South Korea.

WE IDENTIFIED and collecteda unique zoysia genotype in each

major geographic area of the Philippines.On Cebu Island we found primarily Z.matrella on the edges of saltwater fishtanks and on the seacoast beaches. Eventhough few lawns or other areas of culti-vated turf were evident throughout thecountry, those that we found are of afine-leafed Z. tenuifolia. However, theywere usually thought to be bermudgrassby the Filipinos. The U.S. militarycemetery in Manilla has about 460 acresof emerald zoysiagrass. The originalplants were obtained from the BeltsvilleAgricultural Research Center, in 1953.The cemetery grounds are verticut andfertilized once a year. Although the turfwas relatively thatchy, it was beautifuland provided excellent turf.

We feel the genetic diversity of germ-plasm contained in this collection willprovide the industry with the wealth ofdiversity needed to develop improvedturfgrasses for future generations. Thediversity observed among the zoysiaspecies was much greater than we hadanticipated. We look forward to havingthe opportunity to assess selectionscollected and to identify superior geno-types. This will require considerableresearch over an extended period oftime. A few superior genotypes might besufficiently adapted and perform wellenough to be released as new cultivars.If not, they may be a source of germ-plasm for hybridization.

In Taiwan and the Philippines,zoysiagrass was more difficult to findin the wild as well as in cultivation, anddiversity was less than in Japan andKorea. Cultivated turf in both countriesis principally zoysia and bermuda.Northern and southern coastal areasand elevations up to 4,600 feet weresurveyed in Taiwan. Zoysiagrass wasnot found at elevations above 2,000 feet.Several samples of Z. matrella and Z.tenuifolia with considerable diversitywere obtained from coastal areas. Z.japonica was not observed further souththan northern Taiwan. Several samplesof Z. tenuifolia were collected fromcoral reefs on Orchid Island, locatedoff the southeastern coast of Taiwan.During high tide these reefs are com-pletely submerged. The island is inhabitedby an estimated 2,000 aborigines withoutthe conveniences of modern life. Thegenetic diversity observed in Taiwanis well represented among the 53 samplescollected.

have been planted to zoysias that werespecifically selected for some agronomictrait - generally its winter straw color.A considerable amount of time wasspent in surveying public and privatetomb areas, and we collected manyunusual samples. Few, if any, of thetombs received more than periodicattention, no fertilizer, and no supple-mental irrigation. We located tombsestablished in 1200 A.D. of many of theearly kings. Kings' tombs are 60 to 70feet high and 800 to 900 feet in diameter.Most of the public tombs are 50 to 100years old.

The most significant find in Koreawas two additional species, Z. macro-staycha and Z. sinica, not previouslyworked within the United States. Sampleswere obtained of these species whichexisted primarily on the coastline andother high-salt areas, and rice paddyborders. Z. sinica appears to be moredecumbent with a little finer and softerleaves than commonjaponica, but withlarger seed and seed heads. Z. macro-staycha has an upright growth habitand appears stemmy. Although limitedinformation is available, they arereported to be diploid species and notcross compatible with the three previouslyknown species. This, of course, mustbe confirmed.

tices. In addition, we obtained cuttingsfrom 15 accessions that the KGU has intheir research program.

In South Korea, there are only 11 golfcourses, eight of which have been con-structed within the past eight years.Annual precipitation exceeds 67 inchesand temperatures are similar to those ofthe transition zone in the United States.Bentgrass or zoysiagrass is used ongreens, with zoysiagrass or bluegrassused on fairways and roughs. Zoysia wassuccessfully established by seeding onseveral recently constructed courses.Plants appeared surprisingly uniformin newly seeded areas but quite differentin leaf texture in older sod. However,this did not appear to be a problem onroughs or fairways.

Zoysiagrass is called golden grass inKorea because of its winter straw color.Selections are made for plantings basedon shades of brown straw in the winter.There are many golden grass tea roomsand beer parlors. Koreans bury theirdead in earthen tombs or mounds whichstand approximately four feet aboveground level. To hold the soil in place,these tombs are covered with zoysiasprigs. Over a period of time, the tombis entirely covered with zoysiagrass.This procedure has become a ritual overthe past several centuries. Many tombs

Kansai Golf Union Research cen __