African Germplasm Research Articles

Genetic Diversity of Japanese Melon Cultivars (Cucumis melo L.) as Assessed by Random Amplified Polymorphic DNA and Simple Sequence Repeat Markers

The genetic diversity among 67 melon (C. melo L.) cultivars from five Japanese seed companies was assessed using 25 10-mer RAPD primers (56 bands) and nine SSR (36 alleles) markers. These cultivars belong to three horticultural varieties (synom. Groups) spanning eight melon market classes: Group Cantalupensis (market classes Earl’s, House, Galia, Charentais, and Ogen), Group Inodorus [Honeydew and Casaba melons (market classes Amarillo, Piel de Sapo, Rochet, Negro, Crenshaw, and Tendral)], and Group Conomon (market class Oriental). Genetic variation among these cultivars was compared to variation in a reference array (RA) consisting of 34 selected melon accessions from previous studies. Cluster analysis resulted in 11 of 15 Japanese Oriental accessions forming a group with South African RA accessions. The remaining Group Conomon Japanese accessions grouped either with Casaba or with Honeydew cultivars. Japanese Group Conomon accessions and South African RA accessions formed a genetic group that was distinct from all other accessions studied, and suggests either an Asiatic origin for the South African melon germplasm examined or an independent domestication involving similar ancestors. The majority of Japanese House and Earl market class accessions shared genetic affinities, and were genetically different from the Japanese Group Inodorus accessions examined. These Japanese accessions were most similar to Casaba RA accessions. Japanese Galia accessions were similar to either House and Earl’s market classes or to Galia, Ogen, Casaba, and Honeydew RA accessions. Genetic differences exist between melon types that were domesticated from wild, ‘free-living’ subspecies agrestis and from melo.

An evaluation of two collections of South African maize (Zea mays L.) germ plasm: 2. The genetic basis of dry-down rate

Dry-down rate is the loss of moisture from maize kernels over time. This study was undertaken to determine whether collections of early and late flowering South African germ plasm have the same genetic properties with reference to dry-down rate as reported for foreign germ plasm. If so, a dry-down rating may be included in South African maize breeding programmes in order to select for a decreased moisture percentage at harvest. This will facilitate the production of high yielding varieties and hybrids of good quality grain that do not need to be mechanically dried, thus decreasing production costs. To achieve this Griffing's (1956a and 1956b) Model II combining ability analyses were performed on two diallels representing the early and late flowering maize cultivars, respectively. Additive genetic variance was more important in the expression of dry-down rate than dominance, as previously found in foreign germ plasm. This together with the heritabilities estimated, indicate that dry-down rate is amenable to improvement by selection in the germ plasm under investigation. It is concluded and confirmed that dry-down rate is a heritable character and that its inclusion into breeding programmes may play a role in increased profit margins to the producer.

Increasing biodiversity of irrigated rice in Africa by interspecific crossing of Oryza glaberrima (Steud.) × O. sativa indica (L.)

The African rice Oryza glaberrima, traditionally cultivated since more than 3.500 years, is of poor agronomic performance but resistant/tolerant to various stresses and diseases. The introduction of these characters into O. sativa cultivars is difficult since crossing barriers cause spikelet sterility in F1. Backcrossing can restore fertility and recently facilitated the development of fertile O. glaberrima × O. sativa ssp. japonica hybrid progenies for rain fed systems. With the objective to gain access to African rice germplasm for improvement of irrigated rice, crosses were performed with eighteen O. glaberrima and twenty O. sativa ssp. indica accessions. In total about one hundred F1-hybrid grains were obtained. The F1 plants were all completely sterile and backcrossing (BC) to O. sativa was performed in order to restore spikelet fertility. Monitoring of Tog5681 × IR64 hybrid progenies under field conditions revealed a broad genetic diversity within the BC1 and BC2 populations. Some BC1 and BC2 progeny plants outperformed the O. sativa parent, indicating that the heterozygocity level and complementary gene action after two backcrosses are still sufficient to positively influence plant vigor. Spikelet fertility of progenies was highly variable, but almost complete fertility was already observed within the BC1F2 population. High spikelet fertility was preserved in one out of two analyzed BC1F3 families and inmost of the BC2F3 families. The ability to restore spikelet fertility within few generations and the potential of the genetic diversity present in interspecific progenies facilitates the development of plant types specifically designed for the African irrigated and lowland environment.

Responses and genetics of maize germplasm resistant to the maize weevil Sitophilus zeamais Motschulsky in West Africa

The maize weevil, Sitophilus zeamais Motschulsky causes considerable damage to maize grain during storage in the tropics. The objectives of this study were to determine through two experiments the genetic basis of resistance to S. zeamais in African maize germplasm of open-pollinated cultivars, lines and hybrids. The first experiment tested for resistance of 20 maize cultivars (10 white and 10 yellow-grained) developed for lowland Africa grown in three relatively weevil-free savanna locations. The second experiment tested two sets of diallel crosses without reciprocals of 66 F 1 progeny from 12 inbred lines and 78 F 1 crosses from 13 inbred lines of subtropical and temperate origins. Variables studied for the first experiment included husk cover, grain texture, number of egg plugs, number of weevils produced, and number of grains damaged by the weevil. Results showed highly significant differences among the 20 maize cultivars tested. Significant cultivar×location interactions for egg plug and weevil production indicate the importance of environmental effects and complexity in weevil resistance. Of the 20 cultivars tested, Ikenne 83-TZSR-W-1 (open pollinated) and 8329-15 (hybrid) were the most promising for restricted weevil production and minimal grain damage. The results of genetic studies in the second experiment with 144 crosses indicated the presence of genetic differences in maize lines to weevil attack. General combining ability (GCA) and specific combining ability mean squares were highly significant, suggesting that the maize weevil resistance was controlled by both additive and non-additive gene actions and the inheritance was quantitative and polygenic. Among the lines used in the crosses, the two most weevil resistant lines with high GCA effects were TZi 30 (International Institute of Tropical Agriculture) and FLA2BT 106 (Florida).

Genetic diversity in African cucumber (Cucumis sativus L.) provides potential for germplasm enhancement

Genetic diversity among 26 cucumber (Cucumis sativus L. var. sativus) accessions from five African countries [Algeria (1), Egypt (21), Ethiopia (2), Kenya (1), and Libya (1)] present in the U.S. National Plant Germplasm System (NPGS) were examined by assessing variation at 71 polymorphic random amplified polymorphic DNA (RAPD) loci. Genetic distances (GD; simple matching coefficient) were estimated among these African accessions and a reference array (RA) of 21 accessions representative of the genetic variation in cucumber. GD among African accessions ranged between 0.41 and 0.97. GD among accessions in the reference array ranged between 0.36 and 0.88. Multivariate analysis identified three distinct groupings (1–3) of African accessions; Group 1 contained 21 accessions (Egypt, Ethiopia and Libya), Group 2 consisted of two accessions (Kenya, Algeria), and Group 3 possessed three accessions (Egypt). These groupings were distinct from each other (P > 0.001). Accessions in Group 1 differed genetically from all other accessions examined (P > 0.01), and accessions in Groups 2 and 3 were uniquely associated with several RA accessions. While GD among accessions in Group 1 ranged between 0.52 and 0.90, distances among Group 2 accessions varied between 0.93 and 0.97. The GD between the two accessions in Group 3 was 0.65. An accession from Syria (PI 181874) and from one Turkey (PI 199383) were genetically more similar to accessions in Group 1 than to other accessions in the RA. Likewise, accessions in Group 2 were genetically similar to two RA accessions from China and a European glasshouse cucumber line, and Group 3 accessions showed genetic affinities with the U.S. market class cultivar Dasher II. Data suggest that some Egyptian accessions (Group 1) possess unique genetic variation, that this germplasm has potential for broadening the genetic base of commerical cucumber, and that further collection of African germplasm is likely to enhance genetic diversity of cucumber in NPGS.

Chromosomal Polymorphism as Detected by C‐Banding Patterns in Chilean Alfalfa Germplasm 1

A cytogenetic investigation was conducted on the tetraploid alfalfa [Medicago sativa subsp. sativa (L.) L. & L.] Chilean germplasm source PI 536534 using the combined techniques of C-banding and image analysis. Cluster and multiple correspondence analyses were utilized to compare the C-banding patterns of the Chilean germplasm source and the previously published African germplasm source. Cytogenetic analyses revealed polymorphisms for heterochromatic DNA in the 19 plants observed in detail. Abundant variability in the number, intensity, and location of constitutive heterochromatic DNA was noted; however, this variability was not sufficient to preclude recognition of homologous chromosomes. Five out of the 50 plants studied were aneuploids (2n = 4x + 1 = 33 or 2n = 4x − 1 = 31) because of the presence or absence of a chromosome with a satellite. The Chilean karyotype resembled the reference tetraploid African alfalfa karyotype; however, a reduction in the total amount of heterochromatic DNA was observed. Cluster analysis and multiple correspondence analysis based on all eight alfalfa genome chromosomes yielded no clear separation of Chilean and African germplasms. However, the analysis of C-banding patterns of Homolog 1 of Chromosome 8 in Chilean and African germplasms was effective in separating the two germplasm sources with the exception of two individuals from each germplasm source which clustered together.

Distribution and Characterization of Heterochromatic DNA in the Tetraploid African Population Alfalfa Genome

A reference karyotype of tetraploid alfalfa (Medicago sativa subsp. sativa, ) African Population germplasm source (PI 536539) was constructed using the combined techniques of C‐banding and image analysis. The image analysis system is a method of obtaining enhanced images of chromosomes in which morphological data can be obtained for the development of karyotypes. In addition, C‐banding is a diagnostic tool for distinguishing the homologous chromosomes of alfalfa. Chromosome analysis of tetraploid alfalfa revealed that alfalfa has four similar series of chromosomes based on their chromosome morphology and C‐banding. The karyotype of African Population alfalfa germplasm consists of one set of chromosomes with satellites (SATs, Chromosome 8), four sets of submetacentric chromosomes (Chromosomes 1–4), and three sets of metacentric chromosomes (Chromosomes 5–7). All of the chromosomes have centromeric bands and a terminal band on the short arm, with the exception of the SAT. Interstitial bands were observed on the short arm of each of the chromosomes, with the exception of Chromosome 7. Chromosomes 1, 2, and 3 have interstitial bands on their long arms. There exists considerable variability in the number, intensity, and location of the constitutive heterochromatic DNA; however, this variability is not sufficient to preclude recognition of the homologous chromosomes. The chromosome banding pattern of the African Population germplasm resembles the distribution of heterochromatic DNA C‐bands of diploid M. sativa subsp. caerulea (Less. ex Ledeb.) Schmalh. The African Population karyotype of alfalfa developed in this study is suggested as the reference for the development of additional chromosome maps of diverse alfalfa populations.

Analysis of genetic diversity and relationships in East African banana germplasm

The genetic diversity and phylogenetic relationships of 29 East African highland banana (Musa spp.) cultivars and two outgroup taxa, M. acuminata Calcutta 4 and Agbagba were surveyed by RAPD analysis. A genetic similarity matrix was established based on the presence or absence of polymorphic amplified fragments. Phylogenetic relationships were determined by UPGMA cluster analysis. RAPDs showed that the highland bananas are closely related with a narrow genetic base. Nevertheless, there were sufficient RAPD polymorphisms that were collectively useful in distinguishing the cultivars. The dendrogram was divisible into a major cluster composed of all the AAA highland banana cultivars and Agbagba (AAB) and a minor cluster consisting of Kisubi (AB), Kamaramasenge (AB) and Calcutta 4 (AA). Several subgroups are recognized within the major cluster. RAPD data did not separate beer and cooking banana cultivars. Our study showed that RAPD markers can readily dissect genetic differences between the closely related highland bananas and provide a basis for the selection of parents for improvement of this germplasm.

Diversity in landraces and cultivars of bottle gourd (Lagenaria siceraria; Cucurbitaceae) as assessed by random amplified polymorphic DNA

Bottle gourd (Lagenaria siceraria) is an African crop with an ancient pantropicaldistribution. Morphological analyses and archaeological evidencesuggest the oceanic dispersals of wild bottle gourd fruits fromAfrica to Asia and the Americas by 10000–15000 B.P., followedby independent domestications on all three continents. AlthoughAfrican and New World landraces (ssp. siceraria) are morphologically distinct from Asian landraces(ssp. asiatica), siceraria-typemorphological characters in New Guinea germplasm has raised questionsconcerning the origins of Asian landraces, including whether or notthere was early germplasm exchange between Asia and the New World.Another area of confusion in bottle gourd systematics and evolutionconcerns the origins and circumscriptions of commercial cultivars,many of which have been subject to undocumented hybridization andselection practices over the past 100–200 years. To clarify theevolutionary histories of bottle gourd landraces and cultivars, 64random amplified polymorphic DNA (RAPD) markersrepresenting 30 primers were examined in 31 landraces and 43 cultivaraccessions of L. siceraria,as well as in a wild relative, L.sphaerica. Principal component analyses of thecorrelation matrices of the band presence/absence data revealedthe following: 1) southern African germplasm represents adivergent lineage from which several cultivars have been selected;2) New World germplasm is distinct and primarily of Africanorigin(s), but possesses Asian affinities as well; 3)landraces from New Guinea are not related to New World germplasm aspreviously hypothesized; 4) commercial cultivars are diverse intheir geographic origins and genetic compositions; and 5) theintegrity and circumscriptions of some cultivars have been confoundedby production practices allowing gene flow among cultivars.

The use of molecular markers to investigate the genetic structure of an oil palm breeding programme.

RFLP markers (40 probes covering 60% of the oil palm genome) have been used to assess genetic diversity within 54 palms of a specific oil palm breeding programme. A further 10 palms encompassing a broader range of origins were also included to provide a wider framework for comparative analysis. These palms represent a majority of the parents in a crossing programme which aims to combine the best features of African tenera germplasm with South-east Asian Deli dura material. Progeny from these crosses are planted in up to six sites on three continents, where the palms are being assessed in detail for yield components. A total of 157 RFLP bands were scored and the data analysed by calculating genetic distances according to Nei & Li, and by correspondence and cluster analysis. The relationships that emerge through this molecular analysis correspond well with known pedigree and provenance. For example, south-east Asian Deli dura material forms a cluster clearly distinct from AVROS pisifera gene pools, and a selection of African breeding material forms a further and broader grouping. The potential ability of markers to assist in oil palm breeding through examination of the genetic structure of crossing programmes is discussed, as is their value in parental selection to maintain residual diversity within specific breeding pools and use in evaluating the fidelity of breeding lineages.

Genetic enhancement of pearl millet and sorghum for the semi-arid tropics of Asia and Africa

Sorghum (Sorghum bicolor (L.) Moench) and pearl millet (Pennisetum glaucum (L.) R. Br.), ranking fifth and sixth in global cereal hectarage, respectively, are the most important coarse-grain cereals in the semi-arid tropical regions of Asia and Africa. Pearl millet displays better adaptation to and is grown in relatively more marginal environments than sorghum. Under subsistence farming conditions, both crops have low grain yields (0.5-0.7 t·ha-1 for pearl millet and 0.7-0.9 t·ha-1 for sorghum), although improved hybrid cultivars give 3-4 t·ha-1 of realizable grain yields in better-endowed environments. African germplasm, especially Zera Zera sorghums from the Sudan-Ethiopian border in eastern Africa and Iniari pearl millets from the Togo - Ghana - Benin - Burkina Faso region of western Africa, has proved most useful for the genetic improvement of these crops. The greatest impact of improved cultivars (mostly hybrids) has occurred in India, where the area under high-yielding varieties (HYVs) increased from 6% for pearl millet and 3% for sorghum in the triennium 1968-1970 to 53% for pearl millet and 54% for sorghum in the triennium 1992-1994. During the same period, productivity of both crops increased by 59%, which is attributable to both genetic improvement and management factors. HYVs have now started to be adopted in some of the African countries as well (e.g., Chad, Cameroon, Botswana, and Zimbabwe for sorghum; Chad, Namibia, Zambia, and Zimbabwe for pearl millet). The availability of vast untapped genetic resources and continuing yield gains indicate that there are good prospects for future genetic improvement in the productivity of these crops, which can be accelerated with the application of biotechnological tools. Sorghum and pearl millet will continue to be important food crops in their traditional semi-arid tropical areas. Sorghum is already an important feed crop in the developed world and pearl millet has the potential to become an even better feed crop, as it has higher protein content and a better amino acid profile than sorghum. The nutritional value of both crops for food and feed use can be further improved by breeding. Also, through genetic enhancement, there exist opportunities for the development of sorghum and pearl millet cultivars suitable for alternative uses in the bakery and beverage industries.Key words: sorghum, Sorghum bicolor, pearl millet, Pennisetum glaucum, genetic enhancement, semi-arid tropics, Asia, Africa, cultivars, impact.

STABILITY ANALYSIS FOR GRAIN PROTEIN CONTENT IN RABI SORGHUM

In an experiment conducted over three rabi environments, the genotypes E 36-1. Afzalpur local and AGP-280 proved to be more stable for grain protein content with their average response (b, 0.94, 1.108 and 1.18, respectively) and least mean square deviation (Sid -0.387. 0.181 and 0.29, respectively) with significantly higher grain protein content than the experimental mean (12.896%) among the 31 rahi sorghum genotypes, representing the locals of northern Karnataka and eight African germplasm lines obtained from ICRISAT. The genotypes RJ-16. SPV-488 and Bhogapur local had higher magnitude of b-values (>1.3) with more than 13.45 per cent grain protein content, indicating their suitability to high yielding conditions.

Resistance to sweet potato virus disease (SPVD) in wild East African Ipomoea

Summary.Sweet potato virus disease (SPVD), the most harmful disease of sweet potatoes in East Africa, is caused by mixed infection with sweet potato feathery mottle potyvirus (SPFMV) and sweet potato chlorotic stunt crinivirus (SPCSV). Wild Ipomoea spp. native to East Africa (J cairica, I. hildebrandtii, I. involucra and J wightii) were graft‐inoculated with SPVD‐affected sweet potato scions. Inoculated plants were monitored for symptom development and tested for SPFMV and SPCSV by grafting to the indicator plant J setosa, and by enzyme‐linked immunosorbent assay (ELISA). Virus‐free scions of sweet potato cv. Jersey were grafted onto these wild Ipomoea spp. in the field, and scions collected 3 wk later were rooted in the greenhouse and tested for viruses using serological tests and bioassays. In all virus tests, J cairica and J involucra were not infected with either SPFMV or SPCSV. J wightii was infected with SPFMV, but not SPCSV, in the field and following experimental inoculation; J hildebrandtii was infected with SPCSV, but not SPFMV, following experimental inoculation. These data provide the first evidence of East African wild Ipomoea germplasm resistant to the viruses causing SPVD.

Variability in storage response within a coffee (Coffea spp.) core collection under slow growth conditions.

Anin vitro core collection of African coffee germplasm, structured in 32 diploid diversity groups, was established and conserved under slow growth for 3 years (6 subcultures). The initial objective was to store twenty accessions per group, with four replicates per accession. A statistical model was developed to analyse observations of survival rates within each diversity group. The goodness of fit of the model was shown. Survival analysis indicated a broad variability of the accessions in their response to the storage conditions and confirmed the importance of structuring the coffee complex down to the intraspecific level. Intra- and inter-group differences had consequences on the genetic representativity of thein vitro core collection. For practical purposes, conservation was carried on when the intra-group genetic drift was less than 50%.

Evaluation of accessions of south African sorghum germplasm for use in the development of improved varieties

Evaluation of accessions of south African sorghum germplasm for use in the development of improved varieties

A bibliography and review of genetic diversity studies of African germplasm using protein and DNA markers

A review of the existing literature available on the bibliographic CD-ROM PlantGeneCD on the use of protein and molecular markers on plant material from sub-Saharan Africa was undertaken. The review showed that these molecular techniques have been used in a wide range of studies, from measurement of genetic diversity within single population to the elucidation of phylogenetic relationship among species in a genus or group of genera. The review revealed that 67% of the 146 studies examined used protein electrophoresis (58% isozymes, the rest mostly seed proteins), 20% used RFLPs, 8% RAPDs and 3% sequencing. Isozymes have been used for a whole range of applications, whereas electrophoresis of other proteins has mainly been used to study ecogeographic distribution of diversity in crops. RAPDs have been used particularly in the investigation of genetic relationship among accessions of a single species and phylogentic relationship among species. RFLPs of cpDNA have mostly been used at the interspecific level and nuclear markers at the intraspecific level. The studies covered most of the major crop species of Africa and their wild relatives, though important gaps remain, for example sweet potato. So-called “minor” crops were not well represented. Wild taxa not related to crops were also covered, in particular agroforestry and forest species.

A preliminary germplasm evaluation of onion landraces from West Africa

Genetic erosion is observed in traditional populations of onion in West Africa. The present study aimed to assess the agronomical potential for six important traits of 14 landraces collected in West Africa. A multivariate procedure was used to establish a classification within this germplasm on the basis of these traits. The phenotypic variability both within and between landraces is considerable but could be due to traditional agricultural practices still occurring in this area. Three statistically coherent clusters have been identified despite the great phenotypic variation between landraces and could be a basis for building a core collection of West African onion germplasm. This first analysis of traditional onion landraces provides convincing information regarding their agronomic potential. Key words : Allium cepa L., onion, genetic resources, diversity.

The relationship between fall dormancy and germplasm source in North American alfalfa cultivars

Most of the genetic diversity of North American alfalfa cultivars has been accounted for by nine germplasm sources listed in descending order of winter hardiness as follows: Medicago sativa ssp. falcata, Ladak, M. sativa ssp. xvaria, Turkistan, Flemish, Chilean, Peruvian, Indian and African. In most instances, the breeder assigns a fall dormancy score and the relative proportions of each of the nine germplasm source for each cultivar at registration. The fall dormancy score (1 = dormant to 9 = non-dormant), determined by measuring plant height in October after harvest in early September, is used to indicate cultivar adaptation for different regions. This study examines the relationship between germplasm composition and plant height, the equivalence of fall dormancy. The signs on the partial regression coefficients of a multiple regression analysis of plant height on the proportional content of the nine sources of germplasm showed that the fall dormancy fell essentially into two classes, namely, a dormant category, comprising cultivars containing a large contribution of Falcata and Ladak, and a non-dormant category, in which Indian and African germplasm predominate. This does not necessarily preclude the influence of any of the other germplasm sources on fall dormancy, since they represent a rich source of diversity. However, nine distinct classes were not recognisable, perhaps because of the lack of an exact equivalence between fall dormancy class and plant height of the fall regrowth. Since these observations have not been derived in a common nursery, the latitude and latitude × cultivar effects have been disregarded. These limitations should be recognized when using the currently assigned fall dormancy ratings to predict cultivar adaptation. Key words: Alfalfa, fall dormancy, sources of germplasm

Phenotypic Diversity and Patterns of Variation in West and Central African Plantains (Musa Spp., AAB group Musaceae)

Plantains (Musa spp., AAB group) are an important food crop and an integral component of the farming systems in the lowland humid forest zone of West and Central Africa. A group of 24 plantain cultivars, representing the major variability in West Africa, was evaluated for nine quantitative characters. The association between growth and yield parameters in this African plantain germplasm was examined to determine if the pattern of quantitative variation in inflorescence and vegetative traits agreed with taxonomic groupings based on inflorescence type and plant size. Phenotypic correlations between these traits were calculated. Giant cultivars were taller, their pseudostem thicker, and they flowered much later than medium-sized cultivars. Giant cultivars produced more foliage, resulting in heavier bunches with more hands and fruits. Groupings that resulted following principal component analysis (PCA) supported conventional taxonomic groupings of plantains. PC A was based mainly on time to flowering, pseudostem height, and number of fruits. The last two traits, in combination with the number of hermaphrodite flowers and the persistence of the male bud, sufficed to group plantain cultivars.

Regional Diversity in Nondormant Alfalfas from India and the Middle East

Alfalfa (Medicago sativa L.) is an important crop in many desert regions with long growing seasons. Very non‐winterdormant (nondormant) cultivars are derived primarily from germplasm obtained from low elevations in the Middle East and India. Improved understanding of diversity in alfalfas from these regions may enhance conservation and utilization of this germplasm resource. To better characterize patterns of diversity in very nondormant Indian and Middle Eastern alfalfas, we evaluated 34 accessions from low elevations in western, central, and northern India, and throughout the Middle East in a field trial in Tucson, AZ, during 1989 to 1992. Middle Eastern accessions included representatives of geographical groups formulated in previous research. Cluster analysis and plots of the first three principal components of 12 agronomic and six morphological traits were used to describe patterns of variation among accessions. Both analytical approaches showed that Indian accessions were phenotypically distinct from the Middle Eastern germplasm evaluated. Northern Indian germplasm was much more persistent and higher yielding than that from western India and was generally more similar to the majority of Middle Eastern accessions than to accessions from western India. Most accessions from the Gujarat state in western India were exceptional, exhibiting very poor persistence and adaptation to temperatures near 0 °C. Arabian accessions were generally distinctive, especially those from western and southern Arabia which exhibited very rapid regrowth following harvest. Results of this study and previous research suggest that at least six regional germplasm groups exist among nondormant North African, Arabian, and Indian alfalfa germplasm.