Physiological trials with laboratory animals to evaluate nutritional values of plant material in programs for plant breeding and technical research

Plant Foods for Human Nutrition - To be successful in the development of quality in plant products the possibilities for improvement by plant breeding and processing must be weighed against the...     

Development of Nondestructive Screening Methods for Single Kernel Characterization of Wheat

The development of nondestructive screening methods for single seed protein, vitreousness, density, and hardness index has been studied for single kernels of European wheat. A single kernel procedure was applied involving, image analysis, near‐infrared transmittance (NIT) spectroscopy, laboratory density determination, single kernel characterization system (SKCS), and finally Kjeldahl protein determination on the crushed single kernels. Single kernel NIT spectroscopy showed excellent ability to determine protein content, and some ability for determination of single kernel vitreousness. Nondestructive determination of single kernel density, either based on NIT spectroscopy or based on image analysis and kernel weight, needs to be further improved for practical use. The use of SKCS hardness index as a true single kernel hardness reference in a NIT prediction model resulted in a poor predictability. However, by applying an averaging approach, in which single seed replicate measurements are mathematically simulated, a very good NIT prediction model was achieved. This suggests that the single seed NIT spectra contain hardness information, but that a single seed hardness method with higher accuracy is needed to achieve a good NIT prediction model for single kernel hardness.     

Site-related influences on cone-borne inoculum and asymptomatic persistence of Diplodia shoot blight fungi on or in mature red pines

The shoot blight and canker pathogens Diplodia pinea and D. scrobiculata sporulate abundantly on cones of many pine hosts. Variation in incidence and abundance of potential inoculum from cones and frequency of asymptomatic persistence on or in shoots was examined for mature red pines in sites differing in dominant presettlement vegetation and soil type in Bayfield and Douglas counties in northern Wisconsin. Collections were made in each county from 6 plantations, 3 each in areas historically vegetated with jack pine and soils mapped as sands and three in areas historically vegetated with red pine with soils mapped as loamy sands. At each site, 5 cones were collected from each of 5 red pines and 10 shoots were collected from up to 5 red pines. Conidia from cones were quantified with a water wash and filtration technique. Diplodia species were cultured from surface-disinfested asymptomatic shoots. A species-specific PCR assay was used to identify the Diplodia species from cones and shoots. Although cones and asymptomatic shoots from each county yielded D. pinea and D. scrobiculata, D. pinea was detected more frequently. More conidia were obtained from cones from Douglas Co., where there is a history of severe shoot blight damage, than cones from Bayfield Co. In Douglas Co., more conidia were obtained from cones from plantations in areas of more sandy soil and presettlement jack pine dominance than cones from plantations in areas of less sandy soil and presettlement red pine dominance. The numbers of conidia and frequencies of cultural detection of Diplodia species from asymptomatic shoots at a site were positively correlated. These results provide evidence for site-related influences on abundance of pathogen inoculum and asymptomatic persistence on or in red pine crowns that may contribute to differences in frequency and severity of damage from Diplodia shoot blight.     

Near infrared spectra indicate specific mutant endosperm genes and reveal a new mechanism for substituting starch with (1→3,1→4)-β-glucan in barley

Near Infrared Reflectance spectroscopy was tested as a screening method to characterise high lysine mutants from a barley collection by classification through Principal Component Analysis (PCA). Mean spectra of the samples within each cluster identified gene-specific patterns in the 2270–2360 nm region. The characteristic spectral signatures representing the lys5 locus (Risø mutants 13 and 29) were found to be associated with large changes in percentage of starch and (1→3,1→4)-β-glucan. These alleles compensated for a low level of starch (down to 30%) by a high level of (1→3,1→4)-β-glucan (up to 15–20%), thus, maintaining a constant production of polysaccharides at 50–55%, within the range of normal barley.The spectral tool was tested by an independent data set with six mutants with unknown polysaccharide composition. Spectral data from four of these were classified within the high (1→3,1→4)-β-glucan BG lys5 cluster in a PCA. Their high (1→3,1→4)-β-glucan and low starch content was verified. It is concluded that genetic diversity such as from gene regulated polysaccharide and storage protein pathways in the endosperm tissue can be discovered directly from the phenotype by chemometric classification of a spectral library, representing the digitised phenome from a barley gene bank.     

Reliability of pelvimetry is affected by observer experience but not by breed and sex: A cross-sectional study in beef cattle

Pelvis size plays an important role to prevent dystocia in cattle caused by the foeto-maternal disproportion in commonly primiparous females. The reproducibility and repeatability are two important aspects for the reliability of the measurements to use in the selection of cattle for culling. Pelvic measures were taken with a Rice pelvimeter from 224 young cattle (180 females and 44 males) of four beef breeds in South Africa. One experienced and two inexperienced observers each measured pelvic height and width twice. The proportion measurements with a maximum difference of 0.5 cm within animal compared with the first measurement by the experienced observer are around 80% and by the inexperienced observers around 50% for pelvic height and around 60% for pelvic width. Breed and sex do not affect the reliability of pelvimetry by an experienced observer. Under- and overestimation of pelvis size were observed in inexperienced observers, which seems to be unrelated to breed and sex.     

Excised shoots of top-pruned red pine seedlings,a source of inoculum of the Diplodia blight pathogen

Diplodia pinea causes shoot blight and collar rot diseases of pines in forest tree nurseries and sporulates on colonized seedling needles and stems. In late summer 2005, pycnidia of D. pinea were observed on shoots that had been excised by top pruning red pine seedlings earlier that summer during the third season of growth. This observation prompted surveys to determine the incidence and abundance of D. pinea conidia on excised shoots. At each of two nurseries, excised shoots were collected from the seedling canopy and adjacent alleyway soil in two subplots in each of five beds (plots). Excised shoots from both nurseries bore pycnidia with conidia of D. pinea. A water washing and filtration technique was used to quantify D. pinea conidia extracted from these shoots. Excised shoots collected from the seedling canopy yielded more D. pinea conidia than shoots collected from adjacent alleyway soil. Collection and removal of excised shoots resulting from top pruning of pine nursery seedlings should be considered as a means of reducing inoculum in areas where D. pinea is present.     

Gene for improved nutritional value in barley seed protein

Genetically dependent 20 to 30 percent increase in lysine per 16 grams of nitrogen results in improved nutritional values in feeding trials with mice and rats. The recessive gene was selected from the World Barley Collection. Other amino acids are also influenced by the gene. Protein content segregates independently of the changed amino acid pattern. The gene putatively influences the matrix proteins, which characteristically adhere to the starch grains in meal preparations. The morphological character permits rapid microscopic screening of single seeds without affecting viability. Low yield is considerably improved by crossing and selection.     

Bulk Functionality Diversification by Unsupervised Single‐Kernel Near‐Infrared (SKNIR) Sorting of Wheat

We explored the effects of fractioning heterogeneous bulk wheat by fast unsupervised single‐kernel near‐infrared (SKNIR) sorting according to an internal complex NIR functionality trait using a fast prototype kernel sorter designed for postharvest bulk sorting. Sorting into three functionality fractions was performed on low quality lots from an organic field experiment from two growth years and two locations. Sorted lots were mixtures originally diversified by three different preceding catch crops. The resulting 12 fractions, as well as the 12 original wheat lots were characterized by 20 standard quality variables of grains and flours. The data was analyzed by principal component analysis (PCA) and analysis of variance (ANOVA). Within each year and location/cultivar, the SKNIR fractionation had significant positive effect on bulk grain density, protein, wet gluten content, Zeleny sedimentation volume, farinograph water absorption, farinograph softening, falling number, gelatinization temperature, and hardness index. Using the NIR fingerprint directly for sorting without calibration to a univariate reference showed that the resulting fractions were based on the major variance in the entire physicochemical quality trait within each lot as expressed by NIR. This novel unsupervised approach may become a powerful tool for sorting according to complex functionality traits, thus increasing overall quality, applicability, and value of the sorted crop.     

Long-term impact of de-icing salts on tree health in the Lake Tahoe Basin: Environmental influences and interactions with insects and diseases

Lake Tahoe, on the boundary of California and Nevada, is world renown for its natural beauty and is also a popular location for winter-sporting activities. De-icing compounds, such as sodium chloride (NaCl), are used to maintain safe winter driving conditions. Sodium chloride, however, can damage roadside vegetation and affect surface and ground water quality. Our objectives were to: investigate the relationship among salt damage to trees and other damage (from insects, diseases, and other biotic and abiotic factors), examine the effects of vegetation characteristics and environmental factors on salt damage to trees, and to quantify the long-term impacts of de-icing salts on roadside conifers in the Tahoe Basin. From 2006 to 2008, 442 square plots (0.1 ha) were established and surveyed throughout the Lake Tahoe Basin, including 176 control plots > 300 m from roads, and 137 plots originally established in 1990 that were used for long-term trends. Both incidence and severity of salt damage, diseases, insect pests, and other abiotic damage were recorded on all trees within plots (more than 10,000 trees). Soil and vegetation samples were collected from a subset of plots and analyzed for salt content. At least 15% of roadside trees were damaged by salt every year. Very large year-to-year variation in the incidence of salt damage was observed, but the severity of salt damage has decreased since 1990. A clear roadside effect on roadside conifers existed because symptoms of salt damage were only observed on trees in roadside plots and never in control plots, and foliage from trees in roadside plots had more sodium and chloride content than those in control plots for both salt symptomatic and asymptomatic foliage. Incidence of salt damage decreased with increasing distance from roads, was more frequent on rocky soils, and increased with downhill slope steepness and tree density. Pines (Pinus spp.) were more frequently and severely damaged by salt than firs (Abies spp.). Trees were more likely to be damaged by something other than salt, and the relationship among salt damage and other damages was antagonistic rather than synergistic. The results from this study have important implications for the ecology and management of conifer forests in relation to salinity and road maintenance.     

Induction of B cell unresponsiveness to noninherited maternal HLA antigens during fetal life

Patients who have received many transfusions become highly sensitized and develop antibodies against almost all HLA alloantigens, so that finding a cross-match negative kidney donor is difficult. A survey of those patients showed that 50 percent did not form antibodies against the noninherited maternal HLA antigens. Apart from the obvious clinical implications, the data indicate that a human equivalent of murine neonatal or actively acquired tolerance has now been identified.