Molecular characterization of induced mutagenesis through gamma radiation using RAPD markers in Jatropha curcas L.

Genetic variability in Jatropha curcas was induced by different doses (5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 kR) of gamma-rays. Gamma radiation induced earliness in flowering and the plants set flowers earlier than that of control, which took longer duration of 327 days for flowering. The improved reproductive and yield parameters such as days taken to first flowering, flowering population, male to female ratio and seed yield per plant were recorded in 25 kR dose and seed germination in 5 and 10 kR treated seeds. Molecular characterization of induced mutants (M1 generation) with 47 Random amplified polymorphic DNA (RAPD) primers showed 65.27% polymorphism. The variability created by gamma rays ranged from 9 to 28%. The 50 kR mutant was found to be the most diverse from control followed by 25 kR mutant. Thus, this integrated approach can be used for carrying out the mutation-assisted breeding and subsequent selection of desired mutants using molecular markers in J. curcas.Keywords: Jatropha curcas, random amplified polymorphic DNA (RAPD), gamma-rays, induced mutagenesis

Olive phenology as a sensitive indicator of future climatic warming in the Mediterranean

Experimental and modelling work suggests a strong dependence of olive flowering date on spring temperatures. Since airborne pollen concentrations reflect the flowering phenology of olive populations within a radius of 50 km, they may be a sensitive regional indicator of climatic warming. We assessed this potential sensitivity with phenology models fitted to flowering dates inferred from maximum airborne pollen data. Of four models tested, a thermal time model gave the best fit for Montpellier, France, and was the most effective at the regional scale, providing reasonable predictions for 10 sites in the western Mediterranean. This model was forced with replicated future temperature simulations for the western Mediterranean from a coupled ocean-atmosphere general circulation model (GCM). The GCM temperatures rose by 4·5 °C between 1990 and 2099 with a 1% per year increase in greenhouse gases, and modelled flowering date advanced at a rate of 6·2 d per °C. The results indicated that this long-term regional trend in phenology might be statistically significant as early as 2030, but with marked spatial variation in magnitude, with the calculated flowering date between the 1990s and 2030s advancing by 3–23 d. Future monitoring of airborne olive pollen may therefore provide an early biological indicator of climatic warming in the Mediterranean

Schnellwachsende Baumarten im Kurzumtrieb als eine kuenftige Form der Holzproduktion

SIGLETIB Hannover: RA 147(160) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Multilocus analysis of Pinus halepensis MILL. from Spain Genetic diversity and clinal variation

Fifteen populations of Pinus halepensis from Spain were analysed employing 5 polymorphic loci by starch gel electrophoresis. A multilocus approach was used, in order to detect changes in the level of polymorphism and to reveal the pattern recolonization of the species in a North-South direction, leading to a loss of variability among the island and marginal populations. Fifteen populations of Pinus halepensis from Spain were analyzed employing 5 polymorphic loci by starch gel electrophoresis. A multilocus approach was used, in order to detect changes in the level of polymorphism and to reveal the pattern of variation of the species. The multilocus analyses show that large differences exist when island, inland and marginal populations are considered. These differences are quite high in terms of the effective number of genotypes, and in subpopulation differentiation. The multilocus differentiation is mainly caused by relations of allelic frequencies among populations, the most likely cause being that, by chance, alleles were associated differently in the refugia of the species. The population differentiation is large in comparison with that observed in other conifers (FST = 0.11; CFST = 0.17). The canonical variate corresponding to the largest differentiation among populations is positively correlated to the frequency of the most common allele of Mdh4 and Aco and negatively to the frequency of Hk and Pgm2. A clear pattern of variation related to latitude and longitude has been detected by the high correlation with the first canonical variate (r = -0.907 and r = -0.832 respectively). In conclusion, the clinal variation could be attributed to a recolonization of the species in a North-South direction, leading to a loss of variability among the island and marginal populations

Convergence of leaf‐out towards minimum risk of freezing damage in temperate trees

Summary1. Within the same forest stand, temperate deciduous trees generally exhibit a distinct patternin leaf-out timing, with some species flushing earlier than other species. This study aimed toexplain the timing of leaf-out of various temperate tree species in relation to the risk offreezing damage to leaves.2. We combined long-term series of leaf-out date (14–32 years) of five temperate tree specieslocated in both low and high elevations in Switzerland, daily minimum temperatures recordedat the same sites and species-specific freezing resistance (LT50) of emerging leaves. Wecalculated temperature safety margins (the temperature difference between absolute minimumtemperature during leaf-out and species-specific LT50 values), and date safety margins (timelag between the last day when temperature falls below species-specific LT50 values and the dateof leaf-out).3. Leaf-out occurred when the probability to encounter freezing damage approaches zero, irrespectiveof climatic conditions (low vs. high elevation) and species (early- and late-flushing species).In other words, trees leaf out precisely at the beginning of the probabilistically safeperiod. Interestingly, the temperature safety margins did not differ significantly between lowand high elevation. Yet, the date safety margin was smaller at high elevation, presumably dueto a faster increase in temperature during the leaf-out period at high elevation.4. When species-specific freezing resistance is taken into account, the time of leaf-out convergesamong species towards a marginal risk of freezing damage. Thus, leaf-out time haslikely evolved in a way that the risk of freezing damage is minimized over a large spectrum ofclimatic conditions. Species with a small safety margin against freezing temperature, likeFagus sylvatica, appear to employ photoperiod co-control of spring phenology, whereas specieswith a large safety margin depend largely on temperature for the right timing of leaf-out.5. Our results offer a new avenue to explain the differences in leaf-out timing among co-occurringtree species. They further suggest that in a warming climate, tree species can expand theirdistribution range to the extent their phenology matches the stochasticity of freezing temperaturesin spring

Nutzung landwirtschaftlicher Flaechen zur Biomasseerzeugung mit schnellwachsenden Baumarten. Erfahrungen mit der Baumart Aspe Abschlussbericht

To utilise agricultural sites for the production of woody biomass with fast-growing trees in short rotation plantations, new varieties of Aspen were bred. Selected trees of European (Populus tremula L.) and American Aspen (P. tremuloides Michx.) were cross pollinated. Six progenies of these crosses were planted in 1983 in different spacings and rotation periods to test their suitability for this type of biomass production. In the rows the trees were planted at distances of 0.6, 0.9, and 1.2 m with an equal distance of 2.0 m between the rows. The saplings of the closest spacing were harvested after five and again after five years, whereas the saplings of the other two spaces were harvested once after ten years. The average yearly per ha increment of the hybrid-progenies in the 0.9 x 2.0 m spacing after ten years varied between 11 and 15 t dry matter: However, high increments of biomass grew only in the last years of the ten year period. The trial shows that Aspen is able to produce high amounts of biomass on relatively poor sites. For Aspen the minimum rotation period is 10 years. Higher increments are possible when increasing the rotation period which still has to be tested in further trials. (orig./SR)Um die Eignung der Baumart Aspe (Zitterpappel) fuer die Biomasseproduktion im Kurzumtrieb auf landwirtschaftlichen Flaechen zu untersuchen, wurden genetisch definierte Nachkommenschaften auf einem Teilareal der Kurzumtriebsversuchsflaeche Abbachhof in drei Pflanzverbaenden (0,6 x 2,0 m, 0,9 x 2,0 m und 1,2 x 2,0 m) angebaut. Die Nachkommenschaften sind aus Kreuzungen zwischen Elternbaeumen der europaeischen (Populus tremula) und amerikanischen Aspe (P. tremuloides) hervorgegangen und ermoeglichen eine Pruefung sowohl der reinen Arten als auch der Arthybriden. Der Versuch zeigt, dass Aspen fuer die Biomasseproduktion im Kurzumtrieb geeignet sind. Sie vermoegen auf Standorten mit geringer Naehrstoff- und mittlerer Wasserversorgung in extensiver Bewirtschaftung, beachtliche Biomasse zu produzieren. Die erste Beerntung sollte nicht vor Erreichen der maximalen Zuwachsraten (voraussichtlich zwischen 10 und 15 Jahren) erfolgen, um eine moeglichst hohe Biomasseproduktion zu erzielen. (orig./SR)Available from TIB Hannover: F95B1655+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman