Seeding and fertilization effects on plant cover and community recovery following wildfire in the Eastern Cascade Mountains, USA

Slope stabilization treatments are frequently applied following high severity wildfires to reduce erosion, protect water quality, and mitigate threats to human life and property. However, the effectiveness of many treatment options has not been well established. Furthermore, treatments may unintentionally inhibit natural vegetation recovery or facilitate exotic species invasion, compromising long-term ecosystem function. We evaluated the effects of seeding and fertilization treatments on plant cover and vegetation recovery following the Deer Point fire in the Eastern Cascade Mountains of Washington State, surveying vegetation for three consecutive years following fire. We applied a fertilization treatment and two seeding treatments in factorial combination on experimental plots at four sites within the fire. Natural vegetation recovered rapidly on control plots, exceeding 40% average cover the second post-fire year and 53% cover the third year. Seeding and fertilization, applied alone and together, did little to increase total plant cover in any of the three post-fire years. A seed mix containing mostly native species increased seeded species cover, but failed to increase in total plant cover, as reductions in non-seeded species cover largely offset increases in seeded species cover. The seed mix also reduced the cover and frequency of several disturbance-adapted native species and reduced tree seedling abundance by the third year after fire. Exotic species averaged less than 0.5% cover across all treatments, and were not significantly affected by any treatment. Minimal treatment effects on total plant cover suggest that seeding and fertilization did little to reduce erosion hazards. However, seeding with the species mix did interfere with natural vegetation recovery, despite the use of native species and low realized seeded species cover.     

Apple proliferation resistance of <Emphasis Type="Italic">Malus sieboldii</Emphasis>-based rootstocks in comparison to rootstocks derived from other <Emphasis Type="Italic">Malus</Emphasis> species

In three trials carried out over a period of 24 years, open-pollinated seedlings of Malus sieboldii and M. sargentii and 22 apomictic rootstock selections with either M. sieboldii, M. sargentii or M. hupehensis in their parentage were examined for apple proliferation (AP) resistance in comparison to clonal M. x domestica-based rootstocks M 9, M 11, M 13, stocks of the B (Budagovski) and the Polish P series and M. robusta seedlings. Following experimental inoculation or natural infection the Golden Delicious-grafted trees on most of the M. sieboldii-derived progenies showed a high level of AP resistance expressed by low cumulative disease indices, a high percentage of non or little affected trees, low incidence of the small fruit symptom and non or little effect on vigour. Trees on M 9 and M 11, B 118 and M. robusta seedlings were moderately susceptible while trees on progenies with M. sargentii and M. hupehensis parentage, rootstocks of the P series, B 9, B 490 and M 13 proved highly susceptible. The screening also showed that rootstocks with M. sieboldii and M. sargentii parentage are often highly susceptible to latent apple viruses. Trees on most of the M. sieboldii-based progenies were more vigorous than trees on standard stock M 9, whereas the vigour of some progenies from selections with M. sargentii parentage was in the range of M 9 or even lower. Productivity was often correlated with the vigour.     

Simplified method to measure glucocorticoid metabolites in faeces of horses

Glucocorticoids or their metabolites can be measured in several body fluids or excreta, including plasma, saliva, urine and faeces. In recent years the measurement of glucocorticoid metabolites (GCMs) in faeces has gained increasing attention, because of its suitability for wild populations. In horses, however, the group-specific enzyme immunoassay described so far has a limited practicability due to its complex extraction procedure. Therefore, we tested the applicability of other enzyme immunoassays for glucocorticoid metabolites. The present study clearly proved that an enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3α,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. Therefore it was possible to use just a small amount of the supernatant of a methanolic suspension of faeces. The results correlated well with the already described method for measuring GCMs in horse faeces, i.e. analysing the samples with an EIA after a two step clean up procedure of the samples (Merl et al. 2000). In addition, the 3α,11-oxo-A EIA has the advantage of providing a bigger difference between baseline values and peak values after ACTH stimulation. The new assay increased the accuracy of the test, lowered the expenses per sample, and storing samples at room temperature after collection was less critical than with other assays investigated in our study. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports and it shows the importance of choosing an assay which is in good accordance with the metabolites excreted in a given species.     

Agromyza nigrociliata Hendel als Getreideschädling (Dipt.)

Ohne Zusammenfassungmit 3 Text-Abbildungen     

Characterization of ocular gland morphology and tear composition of pinnipeds

Objective The importance of tear film integrity to ocular health in terrestrial mammals is well established, however, in marine mammals, the role of the tear film in protection of the ocular surface is not known. In an effort to better understand the function of tears in maintaining health of the marine mammal eye surface, we examined ocular glands of the California sea lion and began to characterize the biochemical nature of the tear film of pinnipeds. Procedures Glands dissected from California sea lion eyelids and adnexa were examined for gross morphology, sectioned for microscopic analysis, and stained with hematoxylin and eosin. The tear film was examined using interferometry. Tears were collected from humans and pinnipeds for the analysis of protein and carbohydrate content. Results The sea lion has sebaceous glands in the lid, but these glands are different in size and orientation compared with typical meibomian glands of terrestrial mammals. Two other accessory ocular glands located dorsotemporally and medially appeared to be identical in morphology, with tubulo‐acinar morphology. An outer lipid layer on the ocular surface of the sea lion was not detected using interferometry, consistent with the absence of typical meibomian glands. Similar to human tears, the tears of pinnipeds contain several proteins but the ratio of carbohydrate to protein was greater than that in human tears. Conclusions Our findings indicate that the ocular gland architecture and biochemical nature of the tear film of pinnipeds have evolved to adapt to the challenges of an aquatic environment.     

Role of Hec1 in spindle checkpoint signaling and kinetochore recruitment of Mad1/Mad2

The spindle checkpoint delays sister chromatid separation until all chromosomes have undergone bipolar spindle attachment. Checkpoint failure may result in chromosome mis-segregation and may contribute to tumorigenesis. We showed that the human protein Hec1 was required for the recruitment of Mps1 kinase and Mad1/Mad2 complexes to kinetochores. Depletion of Hec1 impaired chromosome congression and caused persistent activation of the spindle checkpoint, indicating that high steady-state levels of Mad1/Mad2 complexes at kinetochores were not essential for checkpoint signaling. Simultaneous depletion of Hec1 and Mad2 caused catastrophic mitotic exit, making Hec1 an attractive target for the selective elimination of spindle checkpoint-deficient cells.     

Protein efficiency ratios and net protein ratios of selected protein foods

As a part of a cooperative study initiated to assess bothin vitro andin vivo protein quality methods, the protein efficiency ratio (PER) and net protein ratios (NPR) of 15 different protein sources were determined. Male weanling Sprague-Dawley rats were fed a 10% protein diet. Fourteen-day NPR and relative NPR (RNPR) values and 14- and 28-day PER and relative PER (RPER) values were calculated for each protein source. When protein quality values were expressed relative to ANRC casein, the 14- and 28-day PER data ranked the protein sources essentially in the same order. RPER values of nonfat dried skim milk (unheated) and tuna were more than 100% that of casein; nonfat dried skim milk (heated), chickpeas, and breakfast sausage were between 50 and 70% of that of casein; and pinto beans and rice-wheat gluten cereal did not support substantial growth of the rat. The NPR method did not always rank the protein sources in the same order as the PER method. For the poor quality proteins, RNPR values were much higher than the RPER values; however, the RNPR and RPER values agreed closely for high quality protein sources.A preliminary report of this work was given at the Annual Meeting of the Federation of American Societies for Experimental Biology, Washington, D.C., March 29–April 2, 1987. Fed. Proc. 1987; 46: 889.