Measurement unit for monitoring of refraction index of air

První část práce je zaměřena na popis existujících metod pro měření indexu lomu vzduchu. Druhá část se zabývá konkrétní úlohou realizace jednotky pro monitorování indexu lomu vzduchu. Index lomu vzduchu je měřen nepřímou metodou založenou na modifikované Edlénově formuli.First part of this work is focused on the description exist methods for measuring refraction index of air. Second part deal with concrete problem realization measurement unit for monitoring of refraction index of air. Refraction index of air is measured indirect method which is based on a modified Edlen formula.

WEEDS PROMOTE THE DEVELOPMENT OF ARBUSCULAR MYCORRHIZAL FUNGI IN ORGANIC WHEAT FIELDS

Understanding the interaction between aboveground vegetation and arbuscular mycorrhizal fungi (AMF) in organic agriculture is of great importance to develop more efficient and sustainable agricultural production systems. This study was conducted to evaluate the effect of weeds on AMF and the effect of AMF on wheat (Triticum aestivum L.) grain quality in an organic field in the weed-free and weedy conditions. The soil microbial profile was characterized using phospholipid fatty acids (PLFA) analysis. We found that the presence of weeds increased the proportion of AMF. The enhanced activity of AMF did not affect the quality of wheat grain grown with sufficient soil phosphorus (P)

Nonclassical light from large ensemble of trapped ions

The vast majority of physical objects we are dealing with are almost exclusively made of atoms. Due to their discrete level structure, single atoms have proved to be emitters of light which is incompatible with the classical description of electromagnetic waves. We demonstrate this incompatibility for atomic fluorescence when scaling up the size of the source ensemble, which consists of trapped atomic ions, by several orders of magnitude. The presented measurements of nonclassical statistics on light unconditionally emitted from ensembles containing up to more than a thousand ions promise further scalability to much larger emitter numbers. The methodology can be applied to a broad range of experimental platforms focusing on the bare nonclassical character of single isolated emitters

Impact of introducing alien storage proteins on the bread-making quality and agronomic performance of spring wheat

Non-Peer Reviewe

Apparent vernalization requirement of high yielding spring wheat

Non-Peer ReviewedControlled environment studies have demonstrated that the high yield potential of certain spring wheat (Triticum aestivum L.) cultivars may result from a moderate vernalization requirement. The objective of this study was to determine whether apparent vernalization responses of cultivars could be detected when comparing the development of early and late-seeded crops. The effect of delayed seeding on 9 or 10 spring wheat cultivars was studied at Saskatoon over a period of four years. Within years, the earliest and latest dates of seeding differed by a minimum of 22 days. Vernalization effects were apparent in 1983 and 1986 but not in 1985 and 1987. In 1983 and 1986 Growing Degree Day accumulation 14 days after seeding (GDD14) averaged 44 for the earliest date of seeding compared to 120 GDD or more for the later seeding dates. However, the GDD14 for the earliest date of seeding was 121 in 1985 and 134 in 1987. Apparent vernalization effects were manifested by higher main stem leaf number, increased spikelet production and delayed spike emergence. Cultivars were ranked in the following order for apparent vernalization sensitivity: Fielder = Pitic 62 > HY402 > HY320 > Genesis > HY912 > Leader > Glenlea > Neepawa > Katepwa > Siete Cerros > Potam. Fielder had the greatest vernalization requirement and Potam the least. On average, delayed seeding resulted in increased grain yields, but this observation was not consistent over years

Improvements in the bread-making quality and agronomic performance of Canadian spring wheats released between 1860 and 1986

Non-Peer ReviewedTwenty eight red spring wheat cultivars ranging from "Red Fife" to "Laura" in vintage were field-tested in each of four years (1989-1992). End-use quality analyses were performed on the grain harvested from three experiments. The objective of this study was to measure the rate of cultivar improvement for agronomic and bread-making quality performance. In the absence of disease, the more modern cultivars yielded 18% more than the cultivars released at the turn of this century. The yield advantage of the modern cultivars approached 30% under leaf rust disease pressure. Yield levels are estimated to be increasing at a rate of approximately 20+ kg/ha/yr. Protein quantity and quality have improved over time as has loaf volume. Improvements in agronomic, disease resistance and value-added performance have been off-set by a slight delay in maturity

Differential competitive ability of morphologically diverse spring wheat genotypes

Non-Peer ReviewedSixteen genotypes of common spring wheat (T. aestivum) were grown under conditions of simulated weed competition at Saskatoon in 1991 and 1992. Weeds consisted of cultivated oat (Avena sativa cv. Waldern) and Oriental mustard (Brassica juncea cv. Cutlass) sown at two densities (48 and 96 seeds m2 per weed species), and a weed free control. Seedling establishment, % ground cover, and seed yield for all three species was recorded as was wheat tiller number, spike number, maximum height, LAI (Ieaf area index), leaf orientation, and flag leaf length and size. Significant (p =0.01) weed rate by genotype interactions involving changes in genotype rank were detected for grain yield, indicating differences in competitive ability existed among the wheat genotypes. The highest yielding genotypes under weed free conditions were not necessarily the highest yielding under weedy conditions. Yield reductions averaged over two weed densities ranged from 36 to 52 %. Genotypes which exhibited lower yield reductions also showed greater suppression of weed growth. Although competitive genotypes were generally taller than non-competitive genotypes, other traits such as tillering capacity and leaf length were important determinants of competitive ability

Performance of standard height and semidwarf durum wheat cultivars under irrigation

Non-Peer ReviewedTall, intermediate, and semidwarf durum cultivars and experimental lines (22 in total) were evaluated at two irrigated sites in 1987. Both tall and intermediate height classes out-yielded the semidwarf group by a significant margin. The standard height durums had a protein content in the 15-16 % range. Starchy kernel content was low at both sites. Smudge and immature kernels resulted in lower CWAD grades but returns from growing durum would still have been greater than that obtained from a CWRS crop. These preliminary results suggest that there is potential for irrigated production of intermediate height cultivars such as Sceptre, Arcola, and Medora

Isolation distances for minimizing out-crossing in spring wheat

Non-Peer ReviewedCurrently recommended isolation distances of three or 10 m for pedigreed seed production of spring wheat (Triticum aestivum L.) may not be sufficient for cultivars with high out-crossing (OC) rates. The detection of higher than expected OC rates in wheat has directed this research to reassess currently recommended minimum isolation distances. The objective of this study was to determine if increased isolation distances are needed for cultivars that exhibit higher than normal levels of out-crossing. In each of two years, OC rates were determined for four Canadian spring wheat cultivars at each of 15 distances (0-33 m) from a blue aleurone pollen source. Cultivars were grown in rows perpendicular to the pollinator block to the north, south, west, & east. Target rows were replicated four times within each direction. Out-crossing in ‘Katepwa’ & ‘Biggar’ was not detected beyond three meters. Cultivars ‘Roblin’ & ‘Oslo’ exhibited higher than normal OC at distances of up to 27m. For Roblin & Oslo, an isolation distance of 30m is recommended to mitigate OC-derived off-types in the subsequent generation of pedigreed seed

Maximizing pre-harvest sprouting in white- and red-seeded wheat

Non-Peer ReviewedSeed dormancy is the main factor responsible for conferring pre-harvest sprouting tolerance to wheat grain. Recently, five common wheat germplasm lines (W98616, Line 211, CDC EMDR-4, CDC EMDR-9, and CDC EMDR-14) with deep seed dormancy levels and differing genetic backgrounds were released by the Crop Development Centre, University of Saskatchewan. The objective of this presentation is to give an overview of (1) the five CDC germplasm lines, (2) the two dormancy breaking methods that effectively overcome the deep seed dormancy levels in the five CDC germplasm lines, and (3) how the two dormancy breaking method can be used by breeders to improve sprouting tolerance within their breeding programs using the five CDC germplasm lines