Pollen competition among Populus deltoides Marsh., P. nigra L. and P. maximowiczii Henry in fertilizing P. deltoides ovules and siring its seed crop

Summary Interspecific pollen competition among Populus deltoides, P. nigra and P. maximowiczii in fertilizing P. deltoides ovules was studied by using a pollen mixture technique, allozymes and leaf morphology. The frequencies of F₁ seedlings of different paternities in pollen-mix crosses showed highly significant (P<0.01) departures from the 11 ratio expected if pollen selection was random. P. deltoides pollen was the most competitive. The mean percentages of F₁ seedlings of P. deltoides paternity in crosses with pollen mixes P. deltodes + P. nigra, P. deltoides + P. maximowiczii, and P. deltoides + P. nigra + P. maximowiczii were 95.0, 92.5, and 84.8, respectively. P. maximowiczii pollen was more competitive than P. nigra pollen, which was at a selective disadvantage. An average of 83.6% of F₁ progenies of the eight crosses with P. nigra + P. maximowiczii pollen showed P. maximowiczii paternity. Also, in four crosses with P. deltoides + P. nigra + P. maximowiczii pollen, the relative proportion of P. deltoides × P. maximowiczii seedlings (13.4%) was higher than that of P. deltoides × P. nigra seedlings (1.8%). Pollen proportions in the pollen mixes and pollen size did not significantly affect the competitive ability of the pollen. The relative pollen competitive ability indicated reproductive affinities among the species.     

Interspecific hybridization of phaseolus vulgaris with P. lunatus and P. acutifolius

Summary The influence of genotypic combinations on the growth of hybrid embryos between Phaseolus vulgaris and P. lunatus, and between P. vulgaris and P. acutifolius was examined. All embryos obtained from P. vulgaris × P. lunatus crosses developed only to a stage which appears to be comparable to the pre-heart-shape stage of selfed embryos. Reciprocal crosses were attempted, but pods abscised at a very early stage. Embryos derived from P. vulgaris × P. acutifolius and reciprocal crosses attained the cotyledon stage although no mature seeds were formed. A distinct characteristic of these embryos was the uneven development of the two cotyledons. The rate of growth and final size of these hybrid embryos seemed to be influenced by the genotypes of both parents.Immature embryos were cultured on defined medium and the effects of glutamine and gibberellin (GA₃) were examined. Glutamine was effective in increasing the survival rate; gibberellin had no apparent effect. Plants derived from cultured embryos of P. vulgaris × P. lunatus, P. vulgaris × P. acutifolius and P. acutifolius × P. vulgaris were obtained.Technical paper No. 00 of the Oregon Agricultural Experiment Station. Research was supported by the Oregon Agricultural Experiment Station, the Research Council of Oregon State University (National Institute of Health Biomedical Research Support Grant RR07079) and the Processor Research Council of Oregon. A.R. is supported by an African Graduate Fellowship from the African-American Institute     

Chloroplast DNA variation in Populus. II. Interspecific restriction fragment polymorphisms and genetic relationships among Populus deltoides,P. nigra,P. maximowiczii,and P. x canadensis

Restriction fragment analysis was conducted to determine interspecific chloroplast DNA (cpDNA) variation and genetic relationships among Populus deltoides, P. nigra, P. x canadensis (P. deltoides x P. nigra), and P. maximowiczii. Total cellular DNAs of these poplars were digested with 16 restriction endonucleases, and Southern blots of the restriction digests were probed with six different cloned cpDNA fragments from Petunia. P. deltoides, P. nigra, and P. maximowiczii each had a distinct chloroplast genome, separated by many restriction-site and restriction-fragment-length mutations, predominantly in the large single-copy region of the genome. P. x canadensis shared the same cpDNA restriction fragment patterns as P. deltoides var. deltoides. P. nigra was most diverged from P. deltoides, and P. deltoides showed close cpDNA relationships to P. maximowiczii. Nucleotide substitutions per site in cpDNA were 0.0036 between P. deltoides and P. maximowiczii, 0.0071 between P. nigra and P. maximowiczii, and 0.0077 between P. deltoides and P. nigra. We suggest that P. nigra should be classified in a new separate section, the Nigrae.     

Chloroplast DNA variation in Populus. I. Intraspecific restriction fragment diversity within Populus deltoides,P. nigra and P. maximowiczii

We examined intraspecific chloroplast (cp) DNA variation within Populus deltoides, P. nigra, and P. maximowiczii by restriction fragment analysis using 16 restriction endonucleases and six heterologous probes of cloned Petunia cpDNA fragments. All three Populus species showed intraspecific cpDNA variation, which was intra- and inter-varietal in P. deltoides, intervarietal in P. nigra, and origin-specific in P. maximowiczii. Two varieties of P. deltoides, var deltoides and var occidentalis, showed distinct cp genomes/DNA. Three distinct cp genomes/DNA, separated by a loss or gain of 1 EcoRV restriction site and/or 1 restriction fragment length polymorphism (RFLP), were observed among the individuals of P. deltoides var deltoides. Within P. nigra, cpDNA of var italica was distinct from that of vars nigra and plantierensis by one RFLP and by a loss or gain of one BamHI restriction site. Populus maximowiczii clones of Chinese origin were separated from those of Japanese origin by a gain or loss of one ClaI restriction site in their cpDNA. The estimate of nucleotide substitutions per site in cpDNA was 0.07% between two varieties of P. deltoides, 0.05% between var italica and var nigra or plantierensis of P. nigra, and 0.01% between Japanese and Chinese accessions of P. maximowiczii.     

Factors influencing bud break and rooting and mass-scale micropropagation of three Phragmites species: P. karka, P. communis and P. australis

A procedure has been described for the large-scale micropropagation of three Phragmites species, P. karka, P. communis and P. australis, from axillary buds excised from the main and side branches. Position of the buds on the branches had an effect on the bud break and establishment of the cultures under in vitro conditions. Lower buds of P. australis and middle buds of P. karka and P. communis were the most suitable. The presence of yeast extract as one of the ingredients of the sprouting medium helped in the early detection of systemic contamination. Multiple shoot formation and root initiation were obtained on Murashige and Skoog's basal medium supplemented with different concentrations of BA – 0.5 mg/l for P. karka, 0.25 mg/l for P. communis and 0.1 mg/l for P. australis– 0.5 mg/l Kn and 2% sucrose (w/v). Shoots and roots elongated on half-strength MS basal medium with 2% sucrose but without any plant growth regulators. A zone of root hair was observed in the case of P. australis. Hardening occurred on 95% of the plantlets within 30 days of transfer to the polyhouse. Over 10,000 plants were produced from three buds of each species within 9 months. The plants were supplied to a private company for their industrial waste treatment. Received: 1 June 1998 / Revision received: 28 August 1998 / Accepted: 10 October 1998     

Analyses of Phaseolus vulgaris L. and P. coccineus Lam. hybrids by RFLP: preferential transmission of P. vulgaris alleles

Summary Restriction fragment length polymorphism (RFLP) was determined among P. vulgaris genotypes and Phaseolus species using 19 probes. The incidence of polymorphism was high (70–86%) between species, but relatively low (22–26%) between genotypes of P. vulgaris. Suitable probes were identified for the analysis of P. vulgaris and P. coccineus hybrids. The segregation pattern in F₂ populations was Mendelian for two probes (LHB and VEE20) and non-Mendelian for GS-g, CHS, and CHI. Statistical analyses indicated gametic selection with preferential transmission of the P. vulgaris alleles, which may account for the selective recovery of P. vulgaris progeny types observed earlier. The available hybrids of P. vulgaris and P. coccineus and the high degree of interspecific RFLP will facilitate the construction of a linkage map for Phaseolus.     

Genetic characterization and relationships of Populus alba,P. tremula,and P. x canescens,and their clones

Summary Isozyme analysis was conducted on individuals of Populus alba L., P. tremula L., and P. × canescens Smith to genetically characterize and differentiate species, hybrids, and individuals, and to determine genetic relationships among them. Thirty gene loci, with 71 alleles, coding for 15 enzymes were observed. Individuals could be identified on the basis of their multilocus genotypes. There were 21 unique multilocus genotypes among 23 P. alba clones. Five P. alba clones from Canada were genetically distinct from each other. Each of the 18 P. tremula and 15 P. × canescens clones had unique multilocus genotypes. Thirteen clones had a unique genotype at a single locus. Percentage of polymorphic loci, average number of alleles per locus, and mean observed heterozygosity were, respectively, 50.0, 1.86, and 0.085 in P. alba, 51.7, 1.66, and 0.096 in P. tremula, and 51.7, 1.86, and 0.157 in P. × canescens. Populus alba and P. tremula were genetically distinct from each other and could be distinguished by mutually exclusive alleles at Aco-3, P. tremula-specific gene Mdh-3, and allele frequency differences at 6 loci. Populus × canescens had allele contributions of P. alba and P. tremula. However, their allele frequencies were closer to those of P. alba than being truly intermediate. The mean genetic identity was 0.749 between P. alba and P. tremula, 0.987 between P. alba and P. × canescens, and 0.817 between P. tremula and P. × canescens. Canonical discriminant analysis of multilocus genotypes separated P. alba, P. tremula, and P. × canescens into three distinct groups and portrayed similar interspecific relationship as above. Our results suggested that the putative P. × canescens individuals consisted of a mixture of F₁ hybrids of P. alba and P. tremula and their backcrosses to P. alba.Presently with the University of Alberta, and BioGenetica Inc., P.O. Box 8261, Edmonton, Alberta, Canada T6H 4P1     

Use of chloroplast DNA polymorphisms for the phylogenetic study of seven Phaseolus taxa including P. vulgaris and P. coccineus

The genetic variability of seven Phaseolus taxa has been evaluated on the basis of molecular data and the results have used to clarify the phyletic relationships between several taxa of the P. coccineus L. complex. Chloroplast DNA (cpDNA) from 33 populations was digested with six restriction endonucleases, revealing some polymorphisms that made it possible to divide most of the taxa into two main groups: the subspecies of P. coccineus on the one hand, and P. vulgaris L., P. polyanthus Greenman and P. costaricensis (Freytag and Debouck) on the other hand. P. polyanthus is closer to P. vulgaris than the other taxa of the second group and should be considered as a separate species. The position of the wild species P. costaricensis is intermediate between P. coccineus and P. polyanthus. P. glabellus shows sufficient polymorphisms at the cpDNA level to be recognized as a separate species, as previously suggested from total seed-protein electrophoretic studies. These results favour the hypothesis of a common phylogeny for P. vulgaris, P. polyanthus, P. costaricensis and P. coccineus from a single wild ancestor. Although cpDNA is generally known to be uniform at the intraspecific level, some additional polymorphisms were also detected within P. vulgaris, P. polyanthus and P. coccineus. Further studies are required to understand the significance of the latter.     

Comparative population studies of threePieris butterflies,P. rapae,P. melete andP. napi,living in the same area

Utilization of patchy habitats by adult populations of three Pieris butterflies, P. rapae, P. melete and P. napi was studied throughout the flight season in an area of their coexistence, about 3×1.5 km, in a farm village in the mountains in Inabu, Aichi Prefecture. Field study was by the mark-recapture method. Results were analyzed by dispersal distances and recapture duration decay curves for adults of different age-classes estimated on the basis of physical condition of their wings, together with supplementary information of daliy egg-laying rate of females, obtained in field cages. Sexually immature, mated femals of P. rapae after teneral stage showed a migratory flight. On the other hand, reproductive females and all males of P. rapae were strongly resident within suitable habitats, and reproductive females begun to lay eggs abundantly at sunny places of newly suitable areas within a short period. P. melete seemed to disperse gradually from emerged stites and females of this species continued to lay some constant numbers of eggs for more than ten days over a wider area. P. napi appeared more like P. melete than P. rapae. The habitats of the three species can be characterized as follows:P. rapae, temporary, continued for pre-reproductive females but localized for reproductive females and all males, and unstable;P. melete, permanent, widespread, and stable;P. napi, permanent, localized, and stable. The numbers of generations of P. rapae, P. melete and P. napi were estimated to be about six, three and three, respectively. Seasonal fluctuations in the number of adults were influenced by the stability of their habitats, i. e., the population size fluctuated sharply in P. rapae, but it was much more stable in P. melete and P. napi. In view of these results, it can be said that P. rapae fits the general characteristics of a r-strategist whereas P. melete and P. napi are more K-strategic than P. rapae.     

Comparative population studies of threePieris butterflies,P. rapae,P. melete andP. napi,living in the same area

The adult populations of three Pieris butterflies, P. rapae, P. melete and P. napi, were studied in an area of their coexistence throughout the flight seasons by using the mark-and-recapture method. The study area, about 3×1.5 km, was set up in a farm village surrounded by the mountainous area in Inabu, Aichi Prefecture. The habitats were qualified by the four factors, i. e., oviposition plants, adult nector plants, roosting-sites and light conditions. Between P. rapae and P. napi, there were sharp differences with regards to overall habitat preferences. P. melete had the widest preferences for all the habitat resources, which overlapped greately with requirements of P. rapae and P. napi. P. melete and P. rapae showed similar preferences for oviposition plants, but the former preferred shaded habitats while the latter preferred sunny places. P. melete and P. napi, having similar preferences for shaded situations, showed differences in the preferences for oviposition plants. Moreover, three species of Pieris were different in their preferences for adult nector plants. Thus, they were more likely to partition habitat resources rather than competing for them. The habitat structures of each species in respect of time, space and stability to weather changes were much different each other in the same area. The habitat of P. rapae was temporary, localized and unstable. While, that of P. melete was more permanent, widespread and stable than that of P. rapae. P. napi seemed to live in the intermediate habitat, i. e., permanent, localized and stable one.     

Hybridisation processes in sympatric populations of pines Pinus sylvestris L., P. mugo Turra and P. uliginosa Neumann

Natural hybridisation was postulated between the closely related pine species Pinus sylvestris and the P. mugo complex, however no clear evidence on propagation of mature hybrids in nature has been documented so far. To test the hybridisation hypothesis we applied chloroplast DNA (cpDNA) markers and isozymes in the analyses of 300 individuals representing the variety of morphological forms in the sympatric populations of P. sylvestris, P. mugo and P. uliginosa at the peat bog complex in the Sudety Mts., Poland. Additionally, the haplotypes of paternally inherited cpDNA of 149 open pollinated progeny derived from seeds were compared to the haplotypes of parental trees to access the intensity and direction of contemporary hybridisation. The morphologically highly variable polycormic (multi-stemmed) hybrids between P. mugo and P. uliginosa were identified. The second group of hybrids was found among the monocormic (single-stemmed) P. sylvestris-like individuals carrying the cpDNA from P. mugo complex. Hybrids of P. sylvestris as a pollen donor and P. mugo or P. uliginosa as a mother were not found, either in the group of examined trees, or among the open pollinated progeny. The results indicate that numerous hybrids can exist in the sympatric population of the species studied and that gene flow can successfully proceed from P. mugo complex to P. sylvestris. Hybridisation and ecological selection seems to play a significant role in diversification and evolution of the investigated species.     

Hemoglobins of baboons, Papio cynocephalus, P. gelada and P. hamadryas

Major hemoglobins of adult Papio cynocephalus, P. gelada, and P. hamadryas and of newborn P. cynocephalus were purified; globins were prepared; and α and β or α and γ chains were separated. The amino acid compositions and aminoterminal groups were determined. These were compared with analogous data for human hemoglobins, other baboon hemoglobins and macaque hemoglobins.     

Comparison of the Esterases and Acid Phosphatases in Paramecium multimicronucleatum,Syngens 1–5, P. jenningsi,P. caudatum,and the P. aurelia Complex1

ABSTRACT. Forty-eight stocks in Paramecium jenningsi, syngens 1–5 of P. multimicronucleatum, P. caudatum, P. primaurelia, P. biaurelia, and P. tetraurelia were grown axenically and tested for their esterases and acid phosphatases using starch gel electrophoresis. The five esterases and the acid phosphatases previously characterized in species of the P. aurelia complex were also found in P. jenningsi, and three to four of the esterases and the acid phosphatases were found in the P. multimicronucleatum species complex and in P. caudatum. Additional subtypes were observed for each of the enzyme phenotypes in these new (though here unnamed) species of Paramecium. Two of the new acid phosphatase subtypes, which depart radically in mobility and in pattern, were found in syngen 3 of P. multimicronucleatum and in P. caudatum. Except for syngens 1 and 5 in P. multimicronucleatum, the degree of similarity between syngens 1, 5 and 2, 3, and 4 appears to be very low—perhaps even lower than that seen for species in the aurelia complex. More realistically, the syngens of P. multimicronucleatum should be considered as separate species although they are not here given separate taxonomic names. Limited sharing of subtypes occurred between species in different species complexes. This observation suggests that the molecular distances between species complexes may be even greater than between species within a complex.     

Plasmodium japonicum,P. juxtanucleare and P. nucleophilum in the Far East*

SYNOPSIS. Plasmodium japonicum and P. juxtanucleare are two very similar species of avian malaria parasites. The former was discovered in domestic fowl in Japan, and the latter in the same host species in Brazil; it has since been found in chickens in Uruguay, Mexico, and Ceylon. The present study, based on a Ceylon strain of P. juxtanucleare and slides from the Bamboo Partridge (Bambusicola thoracica sonorivox) of Taiwan indicates that the latter host is a natural reservoir of P. juxtanucleare, since this species appears to differ in no significant way from P. japonicum. Infection is common in the Bamboo Partridge (5 of 26 birds showed it), but it has not so far been found in any other avian species, although a total of 973 birds, belonging to 17 orders, 45 families, 110 genera, and 183 species, have been examined from this area. Since the younger stages of Plasmodium nucleophilum look very much like similar stages of P. juxtanucleare, they are compared. The older stages however are usually easily distinguishable, and the former species is so far known only from non-gallinaceous birds whereas the latter appears to be limited to gallinaceous ones.     

Characterization of the ribosomal DNA units in two related Prunus species (P. Cerasifera and P. Spinosa)

Summary The genetic relationships between two Prunus species, involved in rootstock breeding, were examined at the level of the ribosomal RNA genes. Twenty clones of P. cerasifera, a diploid species, and 12 clones of P. spinosa, a tetraploid wild species, were studied. The use of three heterologous ribosomal DNA probes covering different regions of the ribosomal tandem repeats enabled us to construct restriction maps for EcoRI and BamHI. We identified two unit types (unit I and unit II) in P. cerasifera. In P. spinosa, P. cerasifera units were present in addition to a third ribosomal unit type (unit III). These results appeared to confirm previous cytological studies (Salesses 1973) indicating that one of the genomes in P.spinosa has homology with the one from P. cerasifera.     

Somatic embryogenesis and shoot regeneration from intact seedlings of Phaseolus acutifolius A., P. aureus (L.) Wilczek,P. coccineus L., and P. wrightii L.

A rapid, one-step procedure has been developed for inducing direct organogenesis and somatic embryogenesis in cultures of Phaseolus coccineus L., P. acutifolius A., P. aureus L. [Vigna radiata L. Wilczek] and P. wrightii L. Development of somatic embryos and shoot buds occurred within 6–8 weeks of culture from intact seedlings raised on MS (Murashige and Skoog 1962) medium supplemented with N⁶-benzylaminopurine (BAP). Shoot buds or embryoids originated from subepidermal tissue of the regions adjacent to the shoot apex, hypocotyl and cotyledonary axils. While P. acutifolius and P. aureus were regenerated via shoot formation and P. wrightii by somatic embryogenesis, both embryogenesis and shoot regeneration were observed in P. coccineus. Relatively higher levels of BAP, 50–80 M, were found to be optimal for inducing regeneration while lower concentrations were ineffective. About 40–70 shoots and 70–250 somatic embryos were produced per responding seedling. Regenerated shoots and somatic embryos developed into whole plants on a basal medium or the one supplemented with 1 M naphthaleneacetic acid.     

Phylogenetic relationships among Puccinia hemerocallidis, P. funkiae, and P. patriniae (Uredinales) inferred from ITS sequence data

Puccinia hemerocallidis and P. funkiae resemble each other morphologically; however, they are biologically and taxonomically distinct, with telia of the former being restricted to species of Hemerocallis and the latter to Hosta species. However, both fungi share a macrocyclic and heteroecious life cycle with Patrinia villosa as the spermogonial and aecial host. An additional microcyclic rust fungus, P. patriniae, is also known on P. villosa. This microcyclic fungus is similar to the two macrocyclic fungi in its telial structure and teliospore morphology. These similarities in morphology and host relationships suggest the three fungi may also share a close evolutionary relationship. To determine the phylogenetic relationships of the three species, a portion of the nuclear ribosomal DNA repeat encoding the ITS and 5.8S subunit regions was amplified by PCR, sequenced, and analyzed. The resulting phylogenetic trees showed that P. hemerocallidis and P. funkiae share a recent common ancestor and that P. patriniae is closely allied with P. hemerocallidis. The results suggest a possible evolutionary derivation of microcyclic P. patriniae from macrocyclic heteroecious P. hemerocallidis, which fits the evolutionary interpretation of correlated species known as Tranzschel's law.     

Pleurosigma hinzianum sp. nov. and P. frenguellianum sp. nov. (Pleurosigmataceae,Bacillariophyta) from Argentinean coastal waters,in comparison with P. amara Stidolph and P. elongatum W. Smith

Two new marine diatom species from Argentinean coastal waters, Pleurosigma hinzianum Sterrenburg, Sunesen & Sar, sp. nov. and P. frenguellianum Sunesen, Sterrenburg & Sar, sp. nov., are described. The characters permitting their identification are specified, based on comparison with type material of the morphologically similar species P. amara Stidolph and P. elongatum W. Smith in the light (LM) and scanning electron microscope (SEM). New information on the type material of P. elongatum is presented and its taxonomic concept is emended. The main criteria for separation of the species discussed here are: valve outline, path of the raphe-sternum, raphe angle and angle of intersection of the oblique striae in LM; and external central and terminal raphe fissures, internal details of the central area, external and internal apical structure, and morphology of the hymen-occluded internal pores in SEM. The occurrence of these (and probably other) species in the genus Pleurosigma in net samples is adventitious and not indicative of a true planktonic mode of life.