Isolation and characterization of eight compound microsatellite markers in a mangrove tree Kandelia candel (L.) Druce

Kandelia candel is an important mangrove tree species of family Rhizophoraceae. Here we isolated eight codominant compound microsatellite simple sequence repeat (SSR) loci from K. candel. Our isolated loci provided compound SSR markers with polymorphism of three to 11 alleles per locus. The expected and observed heterozygosities ranged from 0.230 to 0.887 and from 0.083 to 1.00, respectively. These markers would be the useful tools for analysing questions concerning population genetic structure and mating system of K. candel.     

Light-enhanced carbon dioxide fixation in isolated chloroplasts

Preillumination of leaves of spinach, soybean and maize in theabsence of CO₂ greatly enhanced the capacity for fixing CO₂in an immediately following dark period. Lightenhanced darkCO₂-fixation was further observed in isolated chloroplasts ofspinach and soybean. When isolated chloroplasts were illuminated,CO₂-fixing capacity in the subsequent dark period increasedrapidly at first and later more slowly attaining a stationaryvalue in about 20 min. When the light was turned off at thisstage, the capacity decreased very rapidly becoming zero inabout 10 min. The magnitude of the enhanced dark fixation andits decay in the dark were not influenced by the presence orabsence of atmospheric oxygen. In both leaves and isolated chloroplasts,no significant change in oxygen (21%) occurred in distributionpatterns of radioactivity in products fixed by photosynthetic,or light-enhanced, dark, ¹⁴CO₂-fixation. In preilluminated leaves¹⁴C was incorporated into sucrose in the subsequent dark period,indicating that the photosynthetic carbon reduction cycle isoperating in light-enhanced dark fixation in higher plants. ¹Present address: Noda Institute for Scientific Research, Noda,Chiba Prefecture (Received August 10, 1970; )     

SPECTRAL CHANGE OF LIGHT WITH DEPTH IN SOME LAKES AND ITS SIGNIFICANCE TO THE PHOTOSYNTHESIS OF PHYTOPLANKTON

1. A linear relation was found between the relative light intensityat 5 in depth and the mean chlorophyll a content of the euphoticzone, when they were plotted on logarithmic scales. The intensitiesof underwater lights of different wave lengths were measuredby a photocell with various colored filters. It was recognizedthat with the increase in chlorophyll a content the proportionof blue light fraction became reduced and that of red lightincreased. A similar relation was also found in the sea.
2. Thephotosynthetic rate.light relation was investigated withthesuspension of cultured Chlorella and Tabellaria. At lowlightintensities, the photosynthetic rate for red light waslargerthan those for blue and green lights. The photosyntheticrateunder the mixed light of red and blue was equal to thesum ofthe rates in the individual lights, so far as the intensityof each light was low. But when the intensity of red light wassufficiently high, the addition of blue light brought no furtherincrease in photosynthesis.
3. The photosynthetic rate-depthrelations were investigated bythe surface and underwater exposuremethods. Good agreementswere found between the results obtainedby these two differentmethods. However, there are some discrepanciesbetween the resultsof in situ exposure experiments and thoseobtained by the twomethods.

(Received January 11, 1963; )     

Microsatellite markers for Sachalin fir (Abies sachalinensis Masters)

We developed eight polymorphic microsatellite markers from the Sachalin fir (Abies sachalinensis Masters). The number of alleles per locus ranged from eight to 31, with an average of 21.4. The observed and expected heterozygosities ranged from 0.656 to 0.937 and from 0.710 to 0.945, respectively. These markers will be available for population genetic studies and parentage analysis.     

Isolation of microsatellite markers from Pinus densiflora Sieb. et Zucc. using a dual PCR technique

We developed seven microsatellite loci from Pinus densiflora using a dual polymerase chain reaction (PCR) technique. Of 186 clones from a library based on suppression PCR, 127 contained microsatellite sequences. Of these, 43 candidates were determined sequences of both flanking regions, and 16 regions from this group were chosen as development markers. Seven of these primer pairs successfully amplified polymorphic single loci among 83 resistant trees against pine wood nematode. The observed heterozygosity of the seven microsatellite markers ranged from 0.247 to 0.843. Mendelian inheritance was confirmed using megagametophytes.     

Analysis of genetic structure of a Suillus grevillei population in a Larix kaempferi stand by polymorphism of inter-simple sequence repeat (ISSR)

Clones of ectomycorrhizal fungi can colonize new areas through production of vegetative mycelium or spore dispersal, but the relative importance of these processes in nature is not known. In this study, sporocarps of an ectomycorrhizal fungus, Suillus grevillei , were mapped and sampled from a Larix kaempferi stand at the foot of Mt Fuji. DNA was extracted directly from each sporocarp, and DNA polymorphism was analysed by polymerase chain reaction (PCR) amplification of inter-simple sequence repeat (ISSR) regions primed by (GTG)₅, (GCC)₅ and (GACA)₄. Different sensitivities to detect polymorphism were found among the three primers, with (GACA)₄ showing the highest sensitivity. Forty seven sporocarps were analysed by the three ISSR primers and divided into 34 genets based on combination of PCR fingerprints. In the population 28 genets were represented by individual sporocarps. In most cases, sporocarps grown in aggregation (within a circle of 50 cm diameter) showed some different ISSR band patterns. These results suggest that genets of S. grevillei at the test site are relatively small. The genetic similarities between the 34 genets were also calculated and similarity groups were determined by the criterion that all similarity F values of genets within a group were not <80%. In general, the genets within a similarity group located close to each other. The results of multiple different but highly related genets in a small area suggest that the population of S. grevillei in this stand is not spread and maintained by clonal mycelium extension but is reproduced by spore dispersal.     

Mating system,pollen and propagule dispersal,and spatial genetic structure in a high-density population of the mangrove tree Kandelia candel

Mangrove tree species form ecologically and economically important forests along the tropical and subtropical coastlines of the world. Although low intrapopulation genetic diversity and high interpopulation genetic differentiation have been detected in most mangrove tree species, no direct investigation of pollen and propagule dispersal through paternity and/or parentage analysis and spatial genetic structure within populations has been conducted. We surveyed the mating system, pollen and propagule dispersal, and spatial genetic structure in a natural population of Kandelia candel, one of the typical viviparous mangrove tree species, using nuclear and chloroplast microsatellite markers. High diversity and outcrossing rates were observed. Paternity and parentage analysis and modelling estimations revealed the presence of an extremely short-distance component of pollen and propagule dispersal (pollen: 15.2 ± 14.9 m (SD) by paternity analysis and 34.4 m by modelling; propagule: 9.4 ± 13.8 m (SD) by parentage analysis, and 18.6 m by modelling). Genetic structure was significant at short distances, and a clumped distribution of chloroplast microsatellite genotypes was seen in K. candel adults. We conclude that the K. candel population was initiated by limited propagule founders from outside by long-distance dispersal followed by limited propagule dispersal from the founders, resulting in a half-sib family structure.     

Development and characterization of microsatellite markers in Abies firma and interspecific amplification in other Japanese Abies species

Abies firma is a dominant coniferous tree species endemic to Japan. We isolated eight microsatellite loci from needles of this tree species and tested their polymorphism among 26 A. firma individuals. Six of them showed polymorphism, with two to 16 alleles per locus. Their expected heterozygosities ranged from 0.075 to 0.922. Moreover, interspecific amplification among Abies sachalinensis, Abies mariesii and Abies veitchii was successful in majority of the isolated loci, suggesting that these loci may be useful for characterization of other fir species.     

Development and characterization of ten new microsatellite markers in a mangrove tree species Bruguiera gymnorrhiza (L.)

Bruguiera gymnorrhiza is an ecologically and somewhat economically important mangrove tree species. We isolated 10 polymorphic microsatellite loci from B. gymnorrhiza using a dual‐suppression polymerase chain reaction (PCR) technique. These loci provided microsatellite markers with polymorphism of two to five alleles per locus within 216 individuals from nine natural populations of B. gymnorrhiza on Iriomote Island, the Sakishima Islands, Japan. The expected and observed heterozygosities ranged from 0.220 to 0.720 and from 0.104 to 0.447, respectively.     

Isolation and characterization of 10 new compound microsatellite markers for a mangrove tree species,Avicennia marina (Forsk.) Vierh. (Avicenniaceae)

Avicennia marina is an ecologically important mangrove tree species. We isolated 10 polymorphic microsatellite loci from this species using an improved technique. Our isolated loci provided compound microsatellite markers with polymorphism of two to six alleles per locus. The observed and expected heterozygosities ranged from 0.025 to 0.625 and from 0.096 to 0.767, respectively. These markers would be the useful tools for researching on the genetic diversity and population genetic structure of A. marina.