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The values and variability of 21 traits in 99 hybrids and 21 population forms of winter rye were investigated together in the field and laboratory experiments performed in 6 localities in the years 2003-2005. It was observed that hybrid forms as compared to the population forms are characterizes by a higher crop uniformity of the corn field, higher weight of 1000 grains and resistance to lodging. On the other hand the population forms showed a better pollination of the inflorescences, higher resistance to stem and brown rust and higher protein content. Both forms also differed in the variability of the investigated traits. Hybrid forms were characterized by a higher variability of pollination of the inflorescences and resistance of brown rust while the population forms showed a higher resistance to lodging and stem rust.
W 2004 roku oceniono wartość browarną 60 rodów jęczmienia browarnego i 3 odmian wzorcowych, uprawianych w: ZD HAR Strzelce, SHR Modzurów i ZD HAR Radzików. Oceniane ziarno pochodziło z doświadczeń wstępnych i przedwstępnych z każdej z trzech miejscowości. Wartość technologiczną oceniono na podstawie następujących parametrów jakościowych: masy 1000 ziaren, celności, zawartości białka ogółem i białka rozpuszczalnego słodu, liczby Kolbach, kruchości, ekstraktywności, lepkości brzeczki, siły diastatycznej, zawartości b-glukanów i końcowego stopnia odfermentowania. Dla badanych cech jakościowych oszacowano współczynniki zmienności (CV%) i korelacji (r). Najwyższy efekt interakcji między badanymi obiektami a miejscem uprawy, uzyskano dla: zawartość białka słodu, kruchość słodu oraz zawartości beta-glukanów.
W pracy analizowano zmienność i odziedziczalność cech plonotwórczych wybranych rodów papryki rocznej (Capsicum annuum L.) typu Kambi pochodzenia bułgarskiego. Zmienność i odziedziczalność wybranych cech papryki słodkiej typu Kambi oceniano w pięciu okresach wegetacyjnych (1997-2001). Na podstawie pomiarów biometrycznych roślin papryki oceniono następujące cechy: plon owoców z 1 m2, liczbę owoców z 1 m2, średnią masę owocu, wysokość owocu, szerokość owocu, grubość miąższu, liczbę komór, masę rdzenia, współczynnik kształtu owocu, masę miąższu, masę tysiąca nasion. Odziedziczalność wybranych cech oceniono na podstawie współczynników odziedziczalności (h2) „w szerokim sensie” oszacowanych metodą analizy wariancji ze stosunku wariancji genotypowej do fenotypowej oraz obliczając współczynniki korelacji i regresji rodziców względem potomstw. Współczynnik odziedziczalności oparty na współczynniku korelacji i regresji podano jak dla rośliny samopłodnej. W pierwszym roku badań zwraca uwagę wysoka odziedziczalność badanych cech, przy ocenie na podstawie analizy wariancji. Świadczy to pośrednio o dość dużym zróżnicowaniu genetycznym badanej populacji. W następnych latach, selekcja na cechy plonotwórcze (kształt i masa owoców) spowodowała ujednolicenie genetyczne populacji. „Rozwarstwienie” populacji pojawia się w piątym roku badań. W roku 2001 stwierdzono wysoką odziedziczalność średniej masy owocu (h2=0,88), plonu owoców z 1 m2 (h2=0,80) oraz grubości miąższu (h2=0,93). Odziedziczalność cech obliczona jako korelacja lub regresja wartości cechy rodziców i potomstwa wskazuje na średnią masę owoców, plon z rośliny, masę miąższu, kształt owoców jako cechy o silnej determinacji genetycznej powtarzalnej w latach.
Oceniano zmienność 46 odmian lnu włóknistego z krajowej kolekcji pod względem 12 cech ilościowych (plon ogólny, plon słomy, plon nasion, masa 1000 nasion, zawartość włókna, jakość włókna, średnica łodygi, wysmukłość roślin, długość ogólna, długość techniczna, liczba rozgałęzień, długość wiechy). Do badań przeznaczono odmiany o zróżnicowanym pochodzeniu (Polska, Czechy, Ukraina, Litwa. Rosja, Finlandia, Holandia, Francja, Chiny, Korea). Pomiary biometryczne cech ilościowych wykonano na roślinach pochodzących z trzyletnich doświadczeń polowych. Zmienność określono statystycznie za pomocą odległości Mahalanobisa i współczynników zmienności. Stwierdzono duże zróżnicowanie odmian pod względem wszystkich cech łącznie oraz małe zróżnicowanie pod względem poszczególnych cech traktowanych oddzielnie. Uzyskane wyniki stanowią podstawę wyboru form rodzicielskich do krzyżowania w układzie diallelicznym i określenia ich zdolności kombinacyjnej (GCA, SCA).
The variability of morphological characters of 25 maize inbred lines was studied. Inbreds developed at plant breeding station Kobierzyce consisted of 16 dents, 5 flints and 4 semidents. The degree of inbred ranged from S₈ to S₂₀. The following characters were evaluated: smut infection, root lodging, days from planting to pollen shedding and silking, plant height, ear length, ear diameter, cob diameter, no. of grain rows, no. of grains/ear and grain weight/ear. It was shown that there were differences beteen the lines in regard to the analysed characters. The highest degree of genetic differentiation was found for plant height (h² = 0.94), no. of grains/ear (h² = 0.63) and ear height (h² = 0.57). Low values of genetic variability were calculated for ear length, ear diameter and cob diameter. Out of 25 lines, 17 showed resistance to lodging, whereas two (K 401, K 427) lodged heavily. Smut infection was observed in five lines: K 355, K 372, K 378, K 389 and K 424. The earliest lines were K 341 and K 388 scoring 75 days from planting to silking. Lines K 427, K 423, K 424 and K 420 were late and flowered after 90 days. A few plants in lines K 401, K 420 and K 343 failed to develop ears.
The aim of the studies was to determine genetic crossing potential of 20 maize inbred lines on the basis of general and specific combining ability. Twenty dent inbred lines were crossed with two flint testers giving forty single hybrids. The following characters were analysed: plant height, ear length, no. of grains/ear, % dry matter and grain weight/ear. After estimating general and specific combining abilities, two indices of general and specific crossing potential were constructed. ANOVA showed the significance of general combining ability of maternal lines for all characters with the exception of plant height. General combining ability of testers was significant only for ear length. SCA mean squares were significant for ear length, grain weight/ear and % dry matter. The GCA effects indicated that there was no line which was consistently good in respect to all the characters. Yi index of crossing potential suggested four lines (K 412, S 49759-2-3, K 405 and S 50685) as the most promising. Indices of specific crossing potential (Yij) pointed to the best hybrids and were consistent with general indices of crossing potential.
The range of variability was examined for 8 generative traits of 62 perennial ryegrass strains. These strains were selected from 4 Polish breeding centres. Field experiment began in 2000 was completed in 2002. Very great variability of the most traits was observed, especially for the following traits: number of inflorescences per plant, fertility of spike, number of seeds per inflorescence and a thousand seed weight. Some of the above mentioned traits were connected with the maturity of plants. For example, early matured strains had shorter inflorescence, less number of panicles per inflorescence and smaller seeds. Forms of medium - early maturity - in contrast - had the longest inflorescence, the biggest weight of the thousand seeds, the density of spike and seed weight per inflorescence and per plant. Eleven strains of the highest fertility traits significantly correlated with the seed yield (inflorescence number per plant, spike fertility, seed weight per inflorescence) were selected from the whole population. These strains may be considered as the generative carriers of desirable traits for breeding new perennial ryegrass cultivars.
The study assessed the variability and interrelationships among 7 quantitative traits in a triticale germplasm collection (75 genotypes - cultivars and clones) from the Institute of Genetics, Breeding and Plant Biotechnology University of Agriculture in Lublin. Data came from a trial observed over four years (1996-1999). They were arranged in a complete two-way classification genotypes by years. Variance components were calculated for each character separately. Coefficients of heritability of four-year phenotypic means were done on the basis of the variance components. Multivariate analysis of variance (MANOVA) according to the random model was used to obtain the mean square and cross product matrices for genotype and error source of variation. Phenotypic correlations were calculated from variance-covariance matrices for genotypes in MANOVA. Genetic correlations were calculated using variance and covariance components estimated by the least square method. The MANOVA statement of GLM procedure (SAS) and VARCOMP were used for all computings.
Programme of Conservation and Restitution of the Common Yew in Poland was initiated in 2006. The research determined variability of the species Taxus baccata L. clones originated from different sites, included in the Archive of Clones of Valuable Species in the Forest Inspectorates of Syców. Taxus baccata L. clones were obtained from parent trees growing in the Forest Inspectorate of Lubsko, Wdecki River Landscape Park, Forest Division of Żółwiniec, Forest Inspectorate of Woziwoda, Wierzchlas Reserve and Forest Inspectorate of Czersk. A foil tunnel experiment was established in the Prof. Stefan Białobok Forest Arboretum situated within the Forest Inspectorate of Syców. Each site was represented by the group of 100 clones. Eight months after the date of rooting process commencement the degree of rooting (%), number of lateral branches and length of spring shoots (cm) were estimated. The following morphological and anatomical observations and measurements were carried out: the number of stomatal apparatuses per 25000 pm² and their length (μm), thickness and width of needles (μm), size of needles of the layer of spongy and palisade parenchyma as well as the vascular bundles (μm). The results obtained were analyzed statistically. Cluster analysis was used to distinguish the groups among studied genotypes and to determine the distances between particular groups. Statistically significant variability of Taxus baccata plants originating from different sites was found for all characters studied. The seedlings from the first site - the Lubsko Forest Inspectorate - showed the highest rooting degree as well as the most advantageous number and length of spring shoots. The anatomical features of needles analyzed turned out to be helpful in determination of the variability in studied material relative to the origin.
The investigations carried out at Jadwisin in the years 1998-2002 aimed to determining the effect of nitrogen fertilization (within the range from 0-200 kg N·ha⁻¹) and date of harvest on some tuber composition elements (contents of dry matter, starch, nitrates and total N) in six early potato cultivars of Polish and foreign origin. The tubers harvested after 60 days from planting contained least dry matter at the highest nitrate and total N contents, Acceptable level of 200 mg NO₃·kg⁻¹ fresh matter was exceeded in the tubers of Aksamitka and Gloria potato cvs harvested 60 days after planting at N doses ever 150 ·kg⁻¹. The strongest influence on dry matter and starch accumulation in the tubers showed potato cultivar and the climatic conditions; the effect of nitrogen fertilization, irrespective on the tuber ripeness, ranged within 4-9%. The influence of experimental factors on total N and nitrate contents reached 48-71% for N fertilization, 15-38% for climatic conditions and 3-7% for cultivars at all harvesting terms. The tubers foreign potato cultivars contained more starch and dry matter than the Polish cvs.
Buckwheat is an allogamous species, which is pollinated by insects. The species is distinguishing by a flower dimorphism and a great number of self-sterility genes. Therefore, it is characterized by a large intraspecies variation. The aim of the study was to compare the variation of yielding characters of Red corolla form, of Hruszowska cv., which is one of the initial forms for Red corolla, and Kora cv. Kora is a cultivar of the biggest cultivation acreage. The studies were a part of breeding work, whose aim was to form buckwheat of a stable crop and of a reduced amount of green mass, which is useful for harvesting. The obtained results showed that Hruszowska cv. was distinguishing by a slightly larger variation of the tested characters than Kora cv. and Red corolla form. The seed weight, the plant weight and the number of seeds were characterized by the highest variability. However, the number of nodes on the main shoot (Kora cv. = 17.8%, Hruszowska cv. V = 17.9% and Red corolla form V = 10.2%), the height (Kora cv. V = 18.5%, Hruszowska cv. V = 14.3% and Red corolla form = 15.9%), the thousand seed weight (Kora cv. V = 12.4%, Hruszowska cv. = 11.6% and Red corolla form V = 12.9%), the height of the first inflorescence (Kora cv. V = 18.3%, Hruszowska cv. V = 20.1% and Red corolla form V = 17.8%) and the length of the florescence area (Kora cv. V = 26.1%, Hruszowska cv. V = 25.8% and Red corolla form V = 25.4%) were most stable characters. The largest differences in the variability coefficient were found for the number of seeds per plant (Kora cv. V = 65.8%, Hruszowska cv. V = 65.2% and Red corolla form V = 71.6%), seed weight (Kora cv. V = 61.8%, Hruszowska cv. V = 69.0% and Red corolla form V = 68.0%) and the number of seeds in one inflorescence (Kora cv. V = 44.1%, Hruszowska cv. V = 44.0% and Red corolla form V = 49.9%).
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