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Flower colour polymorphism is attributed to pollinator or non-pollinator mediated selection. Geranium nepalense has common white morph and very rare pink morph. We compared pollinator visitation frequencies, temperature and soil moisture between two morphs in the mixed morph population. We also compared morph ratio and reproductive success between white and pink flower individuals. Our results indicated that no visitor groups were different between two colour morphs. But visitor groups differed in visits between two years. Halictidae preferred pink morph in the year of 2012 but showed no discrimination in 2014, whereas Syrphidae preferred white morph in 2014 but no discrimination in 2012. Overall, pink morph produced more seeds than white morph, but exhibited variation between two years. However, visitor discrimination was not the main cause of the difference in female fitness. Soil moisture was not different between two colour morphs. Temperature of white morph was lower than pink in evening but not different in morning and noon. The results indicated that non-pollinator factors may exert the selective pressure to maintain the flower colour polymorphism in this species. Although pollinators did not exert selection on the flower colour polymorphism, we suggest that they provided potential pollination environment of fluctuating selection to drive flower colour evolution if visitors were limited.
Vitamin D is a compound responsible for maintaining mineral homeostasis. It protects against calcium and phosphate deficiency through the effects on the intestine, kidney, parathyroid gland and bone. All mechanisms that help maintain mineral homeostasis of the body are regulated by the vitamin D hormonal form - calcitriol. Synthesis of vitamin D starts in the skin as a non-enzymatic process, which begins during exposure to sunlight, when the absorption of ultraviolet B (UVB) radiation results in convertion of 7-dehydrocholesterol, a metabolite of cholesterol that is stored in the skin, to precholecalciferol (previtamin-D3) that is immediately converted into cholecalciferol (vitamin D3). After the skin synthesis cholecalciferol is transported to the liver where it undergoes hydroxylation, what results in formation of calcidiol (25(OH) D3). The second metabolic process takes place in the kidney, where calcidiol undergoes hydroxylation at the C-1 position to the hormonal, the most active metabolite - 1,25-dihydroxyvitamin D (calcitriol). Vitamin D deficiency may result in bone diseases, such as rickets in children and osteomalacia and osteoporosis in adults. Symptoms of osteomalacia affect mainly the skeletal system and are similar to that observed in rickets. It concerns thoracic kyphosis, pelvis deformities and also the varus knee. Osteoporosis is another condition that is related to abnormalities of mineral homeostasis. It is characterized by the progressive loss of bone mass, impaired bone microarchitecture, and consequently increased fragility and susceptibility to fracture. For the last several years other, non-classic actions of vitamin D3 have been discussed. It was engendered by the discovery of vitamin D3 receptor (VDR) in the most of body tissues and cells. Hence, there are many hypotheses which suggest the inverse relationship between vitamin D status and various diseases, such as cancer, autoimmune diseases, diabetes mellitus and others.
Three approaches were successfully used to manipulate content of flavonoids in transgenic plants. Overexpressing either the adaptor 14-3-3 protein or genes coding the key enzymes of the flavonoid biosynthesis pathway resulted in a significant increase in the compound content in potato tuber epidermis. The opposite effect was observed in transgenic plants in which these proteins were repressed; this strongly supports the view that the gene construct deiermines transgenic plant feaiures. The most effective construct was, however, the one containing single dihydroflavonol reductase (DFR) gene in sense orientation. In all cases the increase in flavonoid content resulted in the expected enhancement of the antioxidant capacity of tuber extract. At the biochemical level a decrease in the starch content in transgenic plant overexpressing proteins regulating flavonoid biosynthesis was detected. In the case of glucosyl transferase (GT) gene overexpression, the content of phenolic compounds remained at the control level, however, the antioxidant capacity of tuber extracts significantly decreased. The GT plants grew faster glucosylation of flavonoids rather than their quantity which determines transgenic plant features.
W pracy badano plejotropowe efekty genów Ppd1 na plon i jego komponenty w liniach rekom-binacyjnych: Avalon (Mara 2D), Avalon (Ciano 2D), Brigand (Mara 2D), Brimstone (Mara 2D), Brimstone (Ciano 2D), Mercia (Mara 2D), Norman (Mara 2D), Randezvous (Mara 2D) oraz w odmianach Avalon, Brigand, Brimstone, Mercia, Norman i Randezvous. Doświadczenie przepro-wadzono w latach (1997/98, 1998/99) w Gospodarstwie Doświadczalnym w Czesławicach. Każdego roku wysiewano siewnikiem poletkowym około 550 kiełkujących ziarniaków na 1 m2 na poletka o powierzchni 5m2 w czterech powtórzeniach. Analizowano liczbę dni od 1 maja do pełni kłoszenia, wysokość roślin, liczbę kłosków w kłosie, liczbę ziarniaków w kłosie, ciężar ziarniaków z kłosa, masę 1000 ziarniaków, płodność kłoska i plon ziarna z poletka. W dwuletnich badaniach linie rekombinacyjne z genami Ppd1 kłosiły się istotnie wcześniej niż odmiany kontrolne. Wartość niektórych komponentów plonu analizowanych form zależała głównie od roku i w mniejszym stopniu od linii.
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