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Breeding scientists have given extensive attention to triploids in trees because of their importance to forestry. Consequently, creating and breeding triploids of good quality has become one of purposes of tree breeding. We chose two autotetraploids (Betula platyphylla, named Q10 and Q65) as female parents and eight hybrid diploids (B. platyphylla × B. pendula, named F1 – F8) as male parents to obtain progenies through controllable pollination, resulting in triploid progenies. Germination rate and germination energy of triploid seeds of Q65 were significantly higher (P < 0.01) than in triploid seed s of Q10. Triploid families with Q65 as female parent had a large quantity of saplings, whereas triploid families with Q10 as female parent had a small quantity of saplings. Triploid families with Q65 as female parent were generally superior in base diameter and height to base diameter ratio when compared to a diploid family. Q65×F3 was preliminarily recognized as the superior family. These results demonstrate that the female parent has a major influence on triploid progenies, although the male parent also has a small influence. The results provided a reference to build seed orchards of triploid birch trees, choose tetraploids as female parents and forecast triploid families of good quality.
The present experiment was carried out in the period 2006–2008. The aim of this study was to determine the effect of aqueous soil extracts from the soil of a spring wheat monoculture on seed germination energy and capacity, the length of the first leaf and of the longest radicle as well as the number of radicles. Moreover, the content of 0-dihydroxyphenols in the soil was compared in the last year of the study. The soil used to prepare the solutions came from a field experiment established on medium heavy mixed rendzina soil. Spring wheat, cv. Zebra, was grown using plough tillage and two conservation tillage methods in the presence of undersown crops (red clover, Westerwolds ryegrass) and stubble crops (lacy phacelia, white mustard). Germination energy of the seeds watered with the soil extracts from the ploughed plots was significantly higher than this trait in the seeds watered with the extracts from the conservation tillage treatments with spring disking of the catch crops. Germination energy and capacity of spring wheat in the control treatment watered with distilled water were significantly higher compared to the other treatments under evaluation. Spring wheat watered with the aqueous extract prepared from the soil obtained from the plough tillage treatment produced a significantly longer first leaf compared to the treatments in which both conservation tillage methods had been used. The shortest leaf and the lowest number of radicles were produced by the seedlings watered with the soil extract from the treatment with the white clover stubble crop. Radicle length was not significantly differentiated by the soil extracts under consideration. The content of 0-dihydroxyphenols in the rendzina soil determined during the spring period was higher than that determined in the autumn. The content of 0-dihydroxyphenols in the soil was lower in the conservation tillage treatments with autumn incorporation of the catch crops than in the plots in which plough tillage and conservation tillage with spring disking of the catch crops had been used. The type of catch crop used did not have a significant effect on the soil content of these compounds. At the same time, it was found that the treatments in which the catch crops had been sown tended to have higher contents of these compounds compared to the plots without catch crops.
Flaveria bidentis, an annual grass native to South America, has invaded into many countries all over the world, including South Africa and Egypt in Africa, Britain and France in Europe, Japan in Asia, and Australia. In China, this plant species has been widely distributed in Hebei province since 2001 of its first discovery in Tianjin. In salinized soil of northern China, F. bidentis has formed mono dominant communities owing to its opportunistic characteristics. In this study, we investigated germination rate, germination energy, germination index and vigor index in response to different saline-alkaline stresses. Lengths of seedling, hypocotyl, and radicle were also examined. During germination process, germination rate, germination energy, germination index, and vigor index decreased due to higher salinity and alkalinity (pH). Hypocotyl elongation was stimulated at low salinity and alkalinity, but decreased with increasing salinity and alkalinity. The lengths of radicle and seedling were inhibited sharply with increasing salinity and alkalinity. These results suggest that a reciprocal enhancement between salt stress and alkaline stress was a characteristic feature during seed germination of F. bidentis. Ungerminated seeds resumed to germinate after transferred to distilled water, indicating that seeds remained viable during their exposure to saline-alkaline stresses. Stepwise regression analysis indicated that the effects of salinity, alkalinity (pH), and buffer capacity on seed germination and seedling growth were significantly different in magnitude. Salinity and alkalinity (pH) were the dominant factors in seed germination and seedling growth of F. bidentis respectively. burther, the results of this study suggest that F. bidentis has developed excellent adaptative strategy in its early stage of life cycle which partially explains its current invasion success in northern China.
The effectiveness of hydrophobic synthetic polymers in reducing imbibitional chilling stress in germinating bean seeds was evaluated. Two technical polymers and three Polish snap bean cultivars were analysed. Polymers were applied in amounts corresponding to 3.5% of seed weight. In the imbibitional chilling tolerance test, the seeds were rolled up in wet filter paper and left at 5°C for 72 hours, after which they were germinated at 20°C. The seed imbibition rate, germination energy, germination capacity and mean germination time were determined. The poly-mer coatings applied formed a barrier which slowed down seed imbibition, but it also significantly reduced germination energy and led to a decrease in germination capacity. The extent to which imbibitional chilling stress was mitigated was determined by the type of the polymer applied and the bean genotype analysed.
Nasiona koniczyny białej średniolistnej odmiany Barda i wielkolistnej Cyma stymulowano wiązką lasera He-Ne, zmiennym polem magnetycznym oraz kombinacją światła lasera i pola magnetycznego. W badaniach laboratoryjnych określono: energię i zdolność kiełkowania oraz procentowy udział nasion normalnie i nienormalnie kiełkujących, twardych oraz porażonych przez choroby grzybowe. Proces kiełkowania prowadzono zgodnie z zaleceniami ISTA (2009) i Rozporządzenia Min. Roln. i Roz. Wsi (Dz. U. z dn. 28.01.2013 r.). Materiał siewny odmiany Barda charakteryzował się istotnie mniejszą energią kiełkowania oraz zawierał istotnie więcej nasion twardych a mniej nasion normalnie i nienormalnie kiełkujących w porównaniu z odmianą Cyma. Stymulacja elektromagnetyczna w kombinacji L+P istotnie zwiększała udział nasion normalnie kiełkujących u odmiany Barda, a u obu odmian zmniejszała udział nasion nienormalnie kiełkujących.
A laboratory experiment was conducted in 2015 to evaluate the germination energy and capacity of seeds of four ornamental plant species, treated with various biologically active substances. Three replications of the experiment were performed in three independent series. The experimental materials comprised seeds of four ornamental plant species: China aster (Callistephus chinensis (L.) Nees), scarlet sage (Salvia splendens Sellow ex Roemer & J.A. Schultes), common zinnia (Zinnia elegans Jacq.) and French marigold (Tagetes patula L.), which constituted the first experimental factor. The second experimental factor were biostimulants used for seed pre-conditioning: Effective Microorganisms, Trichoderma spp. and Goёmar Goteo. Seeds soaked in distilled water were the control. French marigold seeds were characterised by the highest average germination energy and capacity in three experimental series (mean values) and in each of the series. Scarlet sage seeds had the lowest germination energy, and common zinnia seeds had the lowest germination capacity in experimental series 1 and 3 and in three series (mean values). The biostimulants used for pre-conditioning exerted varied effects on the germination energy and capacity of seeds of the analysed ornamental plant species. The plant species compared in the study responded differently to the tested biostimulants. The germination energy and capacity of seeds of Callistephus chinensis (L.) Ness and Tagates patula L. decreased in response to the applied biostimulants.
W latach 2005-2006 przeprowadzono laboratoryjną ocenę wartości siewnej nasion koniczyny czerwonej – łąkowej, odmiany Dajana. Eksperyment prowadzono metodą kompletnej randomizacji w czterech powtórzeniach. W badaniach uwzględniono dwa czynniki: 1. dolistne dokarmianie borem i molibdenem nasiennej koniczyny czerwonej w następujących dawkach: 0; B-0,3; Mo-0,01; B-0,3 + Mo-0,01; B-0,45; Mo-0,015; B-0,45 + Mo-0,015 kg·ha-1; 2. naświetlanie nasion przed kiełkowaniem rozbieżną wiązką światła lasera He-Ne, o gęstości powierzchniowej mocy 0, 4 i 8 mW·cm-2 (R0, R4, R8), stosowane 1, 2 i 4-krotnie (x1, x2, x4). W materiale siewnym koniczyny czerwonej określono energię kiełkowania, udział nasion normalnie i nienormalnie kiełkujących, twardych, porażonych chorobami grzybowymi oraz ich zdolność kiełkowania. Stwierdzono, że bor w dawce 0,3 kg·ha-1 oraz molibden w dawce 0,01 i 0,015 kg·ha-1 istotnie zwiększały energię i zdolność kiełkowania koniczyny oraz udział nasion normalnie kiełkujących, a zmniejszały - nienormalnie kiełkujących. Molibden, niezależnie od dawki, obniżał udział nasion porażonych chorobami grzybowymi, bor nie miał wpływu na tą cechę, natomiast łączne stosowanie boru z molibdenem zwiększało ich udział. Stymulacja nasion laserem, głównie w wyższej dawce, istotnie zwiększała energię kiełkowania koniczyny czerwonej i udział nasion normalnie kiełkujących oraz obniżała udział nasion twardych, natomiast nie różnicowała zdolności kiełkowania.
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