Search results for "PRODUCTION"
showing 10 items of 7600 documents
Gene regulation in parthenocarpic tomato fruit.
2009
Parthenocarpy is potentially a desirable trait for many commercially grown fruits if undesirable changes to structure, flavour, or nutrition can be avoided. Parthenocarpic transgenic tomato plants (cv MicroTom) were obtained by the regulation of genes for auxin synthesis (iaaM) or responsiveness (rolB) driven by DefH9 or the INNER NO OUTER (INO) promoter from Arabidopsis thaliana. Fruits at a breaker stage were analysed at a transcriptomic and metabolomic level using microarrays, real-time reverse transcription-polymerase chain reaction (RT-PCR) and a Pegasus III TOF (time of flight) mass spectrometer. Although differences were observed in the shape of fully ripe fruits, no clear correlatio…
Nuclear rDNA instability in in vitro-generated plants is amplified after sexual reproduction with conspecific wild individuals
2016
Using micropropagation through tissue culture has become the most used approach worldwide for mass production for the conservation of endangered species. However, the screening of somaclonal variations generated using in vitro culture is usually restricted to the first generation of micropropagated plants, when they have not yet been released in the field. Accordingly, the fate of genetically modified regenerants after sexual reproduction is usually not assessed and changes in the genetic structures of species are unknown. In this work, we assess the cytogenetic stability of two rDNA gene families in the offspring of experimental crosses between accessions generated after in vitro culture a…
Intergenerational fitness effects of the early life environment in a wild rodent.
2019
The early life environment can have profound, long-lasting effects on an individual's fitness. For example, early life quality might (a) positively associate with fitness (a silver spoon effect), (b) stimulate a predictive adaptive response (by adjusting the phenotype to the quality of the environment to maximize fitness) or (c) be obscured by subsequent plasticity. Potentially, the effects of the early life environment can persist beyond one generation, though the intergenerational plasticity on fitness traits of a subsequent generation is unclear. To study both intra- and intergenerational effects of the early life environment, we exposed a first generation of bank voles to two early life…
Do phase-dependent life history traits in cyclic voles persist in a common environment?
2019
Phenotype and life history traits of an individual are a product of environmental conditions and the genome. Environment can be current or past, which complicates the distinction between environmental and heritable effects on the phenotype in wild animals. We studied genome–environment interactions on phenotype and life history traits by transplanting bank voles (Myodes glareolus) from northern and southern populations, originating from low or high population cycle phases, to common garden conditions in large outdoor enclosures. The first experiment focused on the persistence of body traits in autumn-captured overwintering populations. The second experiment focused on population growth and …
Interannual variation and long-term trends in proportions of resident individuals in partially migratory birds
2016
Partial migration - a part of a population migrates and another part stays resident year-round on the breeding site - is probably the most common type of migration in the animal kingdom, yet it has only lately garnered more attention. Theoretical studies indicate that in partially migratory populations, the proportion of resident individuals (PoR) should increase in high latitudes in response to the warming climate, but empirical evidence exists for few species. We provide the first comprehensive overview of the environmental factors affecting PoR and the long-term trends in PoR by studying 27 common partially migratory bird species in Finland. The annual PoR values were calculated by divid…
Low male return rate due to clutch enlargements in the pied flycatcher (Ficedula hypoleuca)
1997
Abstract:Increased investment in reproduction during current breeding event may entail future fitness costs. Even though a wide array of both theoretical and empirical work has been devoted to solve the problem of optimal reproductive rate, evidence for costs of reproduction has been equivocal. In the present study we examined the survival of pied flycatcher parents after a clutch size manipulation where we altered clutch size with one or two eggs. We monitored return rates and dispersal of parents during subsequent years after manipulation. An artificial increase in reproductive effort caused lowered return rates of males. Results on breeding dispersal did not support the explanation that …
Adaptation in response to environmental unpredictability
2017
Understanding how organisms adaptively respond to environmental fluctuations is a fundamental question in evolutionary biology. The Mediterranean region typically exhibits levels of environmental unpredictability that vary greatly in habitats over small geographical scales. In cyclically parthenogenetic rotifers, clonal proliferation occurs along with occasional bouts of sex. These bouts contribute to the production of diapausing eggs, which allows survival between growing seasons. Here, we studied two diapause-related traits in rotifers using clones from nine Brachionus plicatilis natural populations that vary in the degree of environmental unpredictability. We tested the hypothesis that …
Monitoring the reproductive activity in captive bred female ball pythons (P. regius) by ultrasound evaluation and noninvasive analysis of faecal repr…
2018
The royal python (Python regius) is commonly bred in captivity. To have a successful breeding season, accurate monitoring of the reproductive activity is necessary. The use of non-invasive monitoring methods in exotics is important in order to minimize stress. For this purpose ultrasound has been anecdotally used to monitor royal python reproductive activity. However, there is limited information regarding the reproductive cycle of this species. The aim of the present study is to monitor the female reproductive cycle of the royal python using ultrasonography and gonadal steroid metabolite measurements in the faeces. The reproductive activity of one hundred twenty-nine adult female P. regius…
Diploid Ruppia cirrhosa populations from a southern Mediterranean shallow system
2016
Abstract This paper focuses on the morphology and karyology of representative Ruppia populations from a southern Mediterranean shallow system. The cosmopolitan genus Ruppia L. generally inhabits shallow waters such as coastal lagoons and brackish habitats. Ruppia species are characterised by a simplified morphology and high intraspecific phenotypic plasticity. The chromosome number of Sicilian Ruppia populations is reported here for the first time. The analysed populations showed morphological and reproductive characters of Ruppia cirrhosa (Petagna) Grande but a diploid cytotype (2n = 20). A low fruit production was also observed, suggesting that vegetative reproduction is the main reproduc…
Erosion of Lizard Diversity by Climate Change and Altered Thermal Niches
2010
It is predicted that climate change will cause species extinctions and distributional shifts in coming decades, but data to validate these predictions are relatively scarce. Here, we compare recent and historical surveys for 48 Mexican lizard species at 200 sites. Since 1975, 12% of local populations have gone extinct. We verified physiological models of extinction risk with observed local extinctions and extended projections worldwide. Since 1975, we estimate that 4% of local populations have gone extinct worldwide, but by 2080 local extinctions are projected to reach 39% worldwide, and species extinctions may reach 20%. Global extinction projections were validated with local extinctions o…