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Powdery mildew caused by fungi Blumeria graminis f. sp. hordei is one of the most common barley diseases in Polish meteorological conditions. The powdery mildew fungus is made up of different races and forms that are highly specialized. Barley cultivars might be resistant to a certain race of the mildew fungus, but susceptible to another race. Development of the disease is rapid in temperatures from 12 to 20°C, and in humid weather. The aim of the two-year experiment was to assess B. graminis f. sp. hordei virulence frequency and powdery mildew occurrence on five spring barley cultivars. Virulence frequency of the pathogen depended on place and term of exposition. The occurrence of powdery mildew on spring barley cultivars depended on virulence frequency of the pathogen and weather conditions.
Introduction: The Institute of Natural Fibres and Medicinal Plants (INF&MP) is involved in the protection of the genetic resources of flax (Linum usitatissimum L.) and hemp (Cannabis sativa L.). In 1998–2000, the INF&MP conducted research titled “Collection and evaluation of flax and hemp cultivars and ecotypes”. Poland participates in the programme, financed by the Ministry of Agriculture and Rural Development because our country has signed the Convention on Biological Diversity. Objective: The objective of the research was the evaluation of the genetic resources of 23 accessions of flax. The characteristics data for flax accessions are presented according to traditional methodology and according to the methodology for developing the International Flax Data Base. Methods: Field trials were carried out in 1998–2000 in the experimental station in Wojciechów, located in the Opolskie region. The objective was to evaluate the morphological traits, biological features and seed yield of 23 accessions of flax. The research included the following genotypes of Linum usitatissimum L. according to type of use: 12 linseed varieties, three landraces, one accession of unknown type of use, six fibre varieties and one genotype of both types of use. Results: The total plant length of Linum was short for 12 accessions of flax, medium short (7) and medium (4). The technical length was short (17 accessions), medium short (3) and medium (3). The stem thick-ness for all accessions was medium, i.e. between 1.2 and 2.0 mm. The panicle length was short (12 accessions), medium (10) and long (1). A number of primary lateral branches of the stems of all flax accessions was medium (4–8 branches). The 1000 seed weight was low for 21 accessions of flax and very low in two genotypes: Currong and UKR 97 104. The size of the corolla (flower) was small (9), medium (12) and large (2) – varieties: Martin and Maxigold. The petal colour of the corolla was blue (11), light blue (8) and white (4) – Crystal, Hella, Kreola, Achay. Conclusions: Morphological characterisation of the stamen showed that accession K-1390 was segregating because the anther colour was bluish and greish. The highest resistance to lodging was observed for Abby, Peak and Olinette. The following accessions of flax were very resistant to Fusarium: Martin, UKR 97 269, Kijewskij and Ukraińskij 3; resistant to Fusarium: Abby, Peak, Olinette, Crystal, Gold Merchant, Currong and Ukraińskij 2. The following varieties were very susceptible to Fusarium: Hella, Kreola, Maxigold and Achay. These varieties should not be used for cross breeding. The best average seed yield in 1998–2000 in Wojciechów was found in the following accessions of flax: Abby (191%), Gold Merchant (162%), Currong (161%), Olinette (151%), PEAK (148%), UKR 97 269 (148%), Crystal (138%), Ukraiński 3 (132%), Martin (130%), Pacific (110%) and Ukraiński 2 (103%). These varieties are particularly valuable for flax breeders.
The aim of study was an attempt undertaken with Sugar Pfeifer & Langen Poland Industry to develop ad06sory system for commodity ser06ces and sugar beet growers, regarding a decision on the need of chemical control against cutworm. As a result of carried out observations the date of first moth flights, and the total number of the pests on the plantations were determined. Chemical treatments were applied based on the pest warning system, and phenological criteria such as the sum of heat and effective temperatures for the cutworm development. In the study (2009–2012) the chemical control was set on the basis of signaling between 29th and 41th day from the date of mass flight of moths. The date of chemical treatments was determined with the aid of phenological criteria, such as sum of heat in the range from 497.8 to 661.9°C and the sum of effective temperature from 130.6 to 255.8°C.
W latach 2002 i 2003 w doświadczeniu polowym analizowano zmienność siedmiu cech ilościowych u dwóch odmian wyjściowych i 20 mutantów lędźwianu siewnego uzyskanych drogą mutagenezy z krajowych odmian — Derek i Krab. Dla uzyskanych wyników przeprowadzono dwuczynnikową analizę wariancji (obiekty i lata) pod względem wszystkich cech. Oba czynniki istotnie różnicowały wszystkie cechy a interakcje obiekt x lata były istotne dla wszystkich cech na poziomie α = 0,001. Pod względem większości analizowanych cech mutanty ustępowały ich odmianom wyjściowym. Efekt ten był widoczny w pierwszym roku badań (2002). W drugim roku badań (2003), z uwagi na wystąpienie silnego czynnika stresowego, jakim była długotrwała susza, obserwowano obniżenie wartości większości badanych cech obiektów w porównaniu z rokiem 2002. Wystąpienie skrajnie odmiennych warunków środowiskowych umożliwiło ocenę reakcji mutantów na stres wodny i wybrać najbardziej tolerancyjne genotypy.
Right selection of hybrid for cultivation is an especially important issue because maize belongs to a group of plants undergoing considerable breeding development. It is manifested not only in a higher number of new hybrids but also in changes in selection of various breeding types. The field experiments were carried out at the Department of Agronomy of the University of Life Sciences in Poznań, on the fields of the Agricultural-Experimental Station Swadzim in the years 2009-2011. The occurrence of frit fly (Oscinella frit L.) on various maize hybrids (ES Palazzo and ES Paroli – type stay-green) was evaluated, depending on the nitrogen content in the soil, and on the form of a nitrogen fertilizer. It was indicated that the course of weather conditions in the period from sowing until the 5-6 leaf stage (BBCH 15/16) significantly affected the extent of damage caused by frit fly. In the years with a cool spring, percentage of damaged plants was higher. Damage caused by frit fly larvae was directly proportional to the size of the applied dose of a nitrogen fertilizer. The type of a nitrogen fertilizer was not the factor determining the extent of damage caused by this agrophage. Cultivation of stay-green hybrids should be considered as an element of an integrated maize protection against frit fly.
The time, within which accordingly to its application machine works, and an object of work and working groups are under load,is the effective active time. The purpose of the research was the classical and order statistics of effective active time of felling at use chainsaw. The average effective active time of felling of one tree was about 2 s. The cut trees were strong statistical diversified from the point of view of effective active time of felling. The positive skewness coefficient has confirmed, that statistical units with value of feature below arithmetic mean were prevailed – right-sided asymmetry.
The paper presents three methods of localization and estimation of the effects of quantitative trait loci: the method based on the comparison of mean values for marker genotypes, the interval mapping method which uses the linear regression and the composite interval mapping method based on the multiple regression.
In recent years, a local, growing population of cutworm in agricultural fields with various plants such as vegetables, horticultural, and ornamental plants has been observed. The scope of our research covered the observation of two species of cutworms: Agrotis segetum (Schiff.) and A. exclamationis (L.), which are the most dominant species in Poland. Cutworms were monitored in the 2005-2009 season with the use of Delta type pheromone traps with synthetic sexual pheromone and self-catch traps with a light source. The purpose of the research was to determine the dependence between the dynamics of the catches and the location of the traps, in fields with sugar beet, winter barley, and winter wheat in two municipalities: Winna Góra and Więcławice for the two studied cutworm species. Moreover, we used light traps in our analysis of the two studied cutworm species’, flight dynamics in Poznań, Winna Góra, and Więcławice in the 2003-2006 time period. The overall results can be used for adjusting the currently used monitoring methods for short-term and long-term forecasting of cutworm flights, and for optimizing chemical control of the cutworm.
Celem badań była ocena reakcji krajowych odmian na działanie dwóch chemomutagenów i określenie korzystnych kombinacji do ich utylitarnego wykorzystania w mutagenezie lędźwianu siewngo. Nasiona krajowych odmian lędźwianu siewnego — Derek i Krab traktowano dwoma chemomutagenami — N-nitroso-N-metylomocznikiem (MNU) oraz azydkiem sodu (AS) wykorzystując w tym celu traktowania pojedyncze (wyłącznie MNU lub AS) oraz traktowania łączone — AS + MNU i MNU + AS, przy zróżnicowanych dawkach poszczególnych mutagenów. U roślin pokolenia M1 i roślin kombinacji kontrolnej (bez traktowania mutagenami) analizowano wysokość roślin, liczbę rozgałęzień i parametry struktury plonu. Stwierdzono, że zastosowane mutageny i ich kombinacje obniżały wartości badanych cech (z wyjątkiem wysokości roślin), a uzyskane wyniki zależne były od materiału wyjściowego, analizowanej cechy, rodzaju mutagenu, ich dawek oraz zastosowanych kombinacji. Wykazano, że MNU w porównaniu z AS wywoływał wysoki poziom uszkodzeń somatycznych a szkodliwość somatyczna kombinacji łączonych (mniejsza zwłaszcza dla MNU + AS w porównaniu z S.A. + MNU) i zastosowanie dwóch mutagenów o odmiennym wpływie na rodzaj indukowanych mutacji sugeruje ich większą przydatność do indukowania mutacji u lędźwianu siewnego. Ponadto odmiana Derek w porównaniu z odmianą Krab charakteryzowała się większą wrażliwością na zastosowane mutageny i ich kombinacje.
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