Determination of optimum borate concentration for alleviating strength loss during heat treatment of wood

Based on the already established mitigating potentials of borate salt on the negative effects of heat treatment on the strength properties of wood (Awoyemi and Westermark 2005), the optimum concentration of the alkali buffer solution required to minimize strength loss was determined. Wood samples were impregnated with 0.1, 0.3 and 0.5 M sodium borate solution and exposed to heat treatment for 4 h at 200°C. The mitigating effect of borate salt on the degree of strength loss during heat treatment increases significantly with increasing concentration from 0.1 to 0.3 M. Increasing the concentration of sodium borate from 0.3 to 0.5 M did not produce significant differences in the degree of strength loss during heat treatment. The increase in the buffering effect observed with increasing concentration of the sodium borate preservative is more pronounced on the modulus of rupture than on the modulus of elasticity. It is evidenced therefore that the buffering effect of borate salt on the modulus of elasticity of wood exposed to heat treatment did not start significantly until the 0.3 M concentration is reached and further increase in concentration beyond this point did not produce any appreciable improvement in strength properties.     

Plant survival after freezing in wheat 'Cappelle Desprez' ('Bezostaya 1') intervarietal chromosome substitution lines

The effect of individual chromosomes of the wheat variety ‘Bezostaya 1’ on plant resistance to low temperatures was studied using the available set of intervarietal ‘Cappelle Desprez’ (‘Bezostaya 1’) chromosome substitution lines. The number of plants surviving after freezing at ?12, ?15 and ?17°C was determined for both parents and lines in trials in 2004/2005 and 2005/2006. Significant differences between the three temperature treatments and between lines were found, implying that two factors, the level of temperature stress and chromosome substitutions, were influencing plant survival. Improved frost resistance in both trials was associated with genes located on five chromosomes: 5A, 2D, 4A, 5D and 6A. An increase in the plant frost resistance because of the effects of 7A and 1A chromosomes was also observed in the 2005/2006 trial, when the overall autumn and winter (January) temperatures were lower than in 2004/2005.     

牛磺酸对大鼠血压及血管活性物质的影响

通过检测补充不同水平牛磺酸和β-丙氨酸(牛磺酸转运抑制剂)大鼠的血压和血液中血浆肾素活性(PRA)、肾上腺髓质素(ADM)、血清肿瘤坏死因子(TNF-β)、胰岛素样生长因子-I(IGF-I)的含量,探讨牛磺酸对高血压发生的预防作用.试验结果表明,补充牛磺酸可使血液中TNF-α的含量和PRA活性分别降低了23.4%(p<0.05)和30.8%(p<0.05),不同程度地降低了血中ADM、IGF-I的含量.但差异不显著(p0.05).     

Radiographic evaluation of internal defects of seeds of forage grasses

The possibility of using the radiographic method for analyzing the viability of seeds of forage grasses and making a differentiated evaluation of the effect of various types of latent defects of the internal structure of seeds on their sowing qualities is shown.     

Change in polysaccharide content in grain raw material during preparation for producing whole grain bread under enzymatic hydrolysis conditions

Results of investigating the effect of enzymatic treatment during soaking of wheat and triticale grain on a change in its moisture and polysaccharide content in the grain mass are presented. The expediency of using the preparation Celloviridin G20x when preparing grain for producing whole grain bread is shown.     

Radiation effects on potential number of grains per spike and biomass partitioning in two- and six-rowed near isogenic barley lines

The critical period for yield determination in barley (Hordeum vulgare L.) is situated in the pre-heading phases. During the latest part of the critical period one of the most important yield components (i.e. the number of grains per spike) is set in two- and six-rowed barley. In wheat, much is known about the role of the spike in assimilate acquisition for the establishment of grains per spike, but not in barley. This paper evaluates how biomass partitioning between vegetative and reproductive organs impacts floret development and primordia survival in response to radiation during different periods in the crop cycle, in barley lines. Field experiments were carried out using two- and six-rowed near isogenic barley lines differing only in spike type. Shading treatments were applied at different periods during the crop cycle (from 60 to 15 days before and after heading) reducing the intercepted radiation (ca. 70%). Dynamics of floret primordia initiation and mortality and of floret development for different spikelet positions along the spike were measured, and biomass partitioning between vegetative and reproductive structures was calculated.

Pre-heading shading reduced fertile florets per spike (P < 0.001). In the immediate pre-heading treatment, distal floret primordia could not reach a fertile floret stage due to a low rate of floral development.

The amount of assimilates partitioned to the spike at heading affected the number of fertile florets per spike in both barley types. However, when spike biomass at heading was corrected by nitrogen concentration, the fitness of the relationship did not improve in relation to the first one. In relative terms, radiation restrictions during the immediate pre-heading phase increased the amount of biomass partitioned to the growing spike.     

Reliability of InGaAs focal plane array imaging of wheat germination at early stages

To assist our Kansas breeding program, we have developed nondestructive methods to test new lines of wheat for resistance to premature germination. The high sensitivity of subsurface imaging, compared with visual detection, α-amylase determination, or viscosity testing, permits germination detection at early stages. This report is concerned with detection reliability via chemical imaging of intact wheat kernels at early stages of germination by using an InGaAs focal plane detector array in the 1100–1700 nm range. Ninety kernels from each of six different cultivars, including HRW and HWW wheat, were exposed to moist conditions for 6, 12, 24, 36, and 48 h. Images of each 90 kernel group were examined, and images of those kernels exposed to moisture for 36 h were compared with images of kernels treated for 3 h as a control. Images of each were classified as sprouted or unsprouted. Criteria for classification included images of log 1/R at select wavelengths or images of select factors resulting from principle component analysis (PCA) treatment of reflectance intensity data from each pixel. Sprouted kernels determined by PCA factors 1 and 4 from 90 kernels tested in a 36-h moisture exposure numbered 87, 85, 80, 74, 70, 48 for six cultivars tested. Cultivar KS-2174 was shown to be distinctly more resistant to germination than the other cultivars. When KS-2174 was compared with Betty wheat, for all exposure times, Betty had approximately 45% more germinated kernels.     

An Altered aroA Gene Product Confers Resistance to the Herbicide Glyphosate

The hypothesis that the herbicide glyphosate (N-phosphonomethylglycine) acts on plants and microorganisms by inhibiting synthesis of 5-enolpyruvyl-3-phosphoshikimate, a precursor to aromatic amino acids, was tested. Salmonella typhimurium was treated with ethyl methanesulfonate, and mutants mapping at the aroA locus, which encodes 5-enolpyruvyl-3-phosphoshikimate synthetase, were isolated by selection for glyphosate resistance. One of the mutants results in the synthesis of a 5-enolpyruvyl-3-phosphoshikimate synthetase that is resistant to inhibition by glyphosate. The mutant aroA gene and the corresponding wild-type allele were cloned. The mutation confers high resistance to glyphosate when introduced in Escherichia coli in the presence or absence of the wild-type aroA allele.