The Investigation of Several Species of Bacillus to Determine their Potential as Biocontrol Organisms on Wheat

Of twenty Bacillus species tested, only five were capable of I vitro inhibition of several wheat pathogens. The mode of inhibition of these five Bacillus species was due to the production of an extra cellular peptide antibiotic which caused disruption of the plasma membrane. Various other physical and chemical characteristics of the antibiotics were also investigated. When applied as seed treatments on spring wheat, the five Bacillus species did not produce significant yield differences. Low soil temperatures at spring wheat planting may have been responsible for the failure of response. The five Bacillus species, B. subtilis var. niger (originally received as B. globigii), B. subtilis, B. polymyxa, B. thuringiensis subsp. Sotto and B. sibtilis (originally received as B. uniflaellatus) required a temperature of 14 C or higher to grow and a temperature of 16 C or higher to produce their antibiotic(s). Our results also indicated that six phytopathogentic organisms, used as test organisms, are capable of growth at temperatures of 10 and 12 C. Soil temperatures at spring wheat planting time are generally 7-10 C and may be too low to allow for Bacillus success as a biocontrol agent

The Decompostion of Organic Matter in Two Midgrass Prairies in Western South Dakota

All ecosystems have two basic biological components. One component is the autotrophic organisms which fix energy from the sun and use inorganic substances to create food. The other is the heterotrophic organisms which utilize the stored food of the autotrophs, rearrange it, and finally decompose the complex materials into simple inorganic compounds. The autotrophs, which are predominantly green plants, grow wherever the most sunlight is available, heterotrophs predominate wherever organic matter accumulates, primarily in the upper layer of the soil. Heterotrophs consist of consumers which feed on green plants and other organisms. Decomposers, chiefly bacteria and fungi that break down the complex co pounds of dead organic matter, utilize part of it, and also release some of the simple substances back into the ecosystem again. For a biotic community or ecosystem to exist, there must be a supply of energy. The ultimate source of this energy for the earth is sunlight. The green plants, through photosynthesis, utilize this energy and manufacture foodstuff. The energy stored as cell. substance in the green plants is ultimately dissipated and recycled throughout the ecosystem by a complex system known as a food chain. The plants and animals in an ecosystem are interlinked in a complex system by means of which the basic chemicals of life are constantly recycled . The major role played by decomposer microorganisms is the breakdown and decay of dead organic matter and the consequent return of its chemical constituents to the soil or atmosphere for reuse by other organisms. Without the decay of organic matter, minerals would be tied up in the organic matter, and organic debris would eventually accumulate to such high levels that life would cease to exist. Decomposer organisms may also play another important role during the process of decomposition. Russell holds the view that the C02 produced during decomposition may be used by plants through their roots or absorbed by their leaves. The C02 produced during decomposition, instead of being released immediately to the atmosphere, is concentrated in the plant canopy and is available for immediate use by the plants. Under intensive farming a high level of organic matter would be beneficial since the C02 released would benefit plant growth

Evaluation of Giant Canada Goose Restoration in Western South Dakota

A study of giant Canada goose (Branta Canadensis maxima) restoration in western South Dakota was conducted during 1970 and 1971. Nesting, production and mortality, homing, and pioneering were evaluated both years. Nesting began April 4 in 1970 and extended for 73 days, but the peak of nesting occurred from April 29 to May 5. In 1971, nesting began April 1 and continued for 69 days, with the peak occurring April 8-14. The peak of hatching occurred June 6-12 in 1970 and May 8-14 during 1971. Small stockponds were utilized for nesting both years. Islands were preferred nesting sites. Peninsulas and shore sites contained over half of the nests and artificial structures were also used. Of the 82 nest observed, 85 percent were in ungrazed areas. Nests on land were found an average of 27 feet from water and 68 percent were within 15 feet. The mean elevation above water was 3.4 feet for all nests; 3.7 feet for land nests and 1.6 feet for nests in artificial structures. Almost all nest sites were found in relatively bare areas and afforded maximum visibility for the nesting geese. Thirty-four plant species were observed at nest sites, but no species was preferred. Thirty-two clutches has 158 eggs during 1970, and 50 clutches had 273 eggs during 1971; mean clutch size was 4.9 eggs in 1970 and 5.5 in 1971. Clutches ranged from 2 to 9 eggs during the 2-year period. Clutches of 1 to 4 eggs had 45.5 percent hatchability, and larger clutches of 5 to 9 eggs had hatchability of 73.1 percent. Of the 82 nests, 78.1 percent successfully hatched and 15.9 percent were destroyed; 12.2 percent by mammalian predators and 3.7 percent by flooding. Desertion occurred in 3.6 percent of the nests, and eggs in 2.4 percent were incubated but failed to hatch. Infertility accounted for 14.2 of the egg loss. Embryonic death occurred in 5.6 percent of the eggs, and 11.8 percent were destroyed. During the 2 years, 293 goslings were produced form 64 nests. Of these, 263 (89.2 percent) were raised to flight stage. Ninety-one percent of the gosling mortality occurred during the initial 2 weeks following hatching when broods were moving between water areas. Broods in the Belvidere area moved an average of 2.7 miles before congregating on a rearing-molting area. The sex ratio of 136 adults homing to the study area was 1.1 females per male and 29 yearlings that homed had a sex ratio of 2.2. Pioneering was limited both years. Seventy percent of the geese were recaptured within 5 miles of the dam on which they were reared or released in previous years. The mean distance moved from the original release site to the site of recapture was 1.0 miles. Of 64 geese released in 1970, 6 pairs that returned in 1971 were observed to have pioneered an average of only 3.4 miles from the release site. High nest success, low mortality of goslings, and homing to the area of release have all contributed to the success of the restoration project. The population is now self-sustaining and will continue to grow if factors affecting production remain favorable and mortality factors do not increase appreciably

Selected Anatomical and Physiological Responses as Affected by a Rope-skipping and Cycling Program for College Women

The purpose of this study was to test the effects of a bicycle ergometer program and a rope-skipping program on the cardiovascular efficiency of a selected group of college freshman women. The effects of the two programs on percent body fat, body weight, strength, and endurance were also tested. During the course of this study, the following hypothesis was tested: There are no significant differences among a rope-skipping group, a bicycle ergometer-exercising group, and a control group in the development of selected anatomical and physiological responses. 1. The subjects involved in this study were thirty-three freshman women from basic instruction classes in physical education for the spring semester, 1971, at South Dakota State University. 2. No subject involved in an intercollegiate or extramural activity was allowed to participate in this study. 3. The training program consisted of four sessions per week for five weeks for each subject. 4. Only the parameters of predicted maximal oxygen uptake, body fat by skinfold measurements, muscle strength and endurance, and body weight were tested. 5. No effort was made to control the subjects: diet, sleep or other aspects of personal life. They were asked, however, not to change their normal habits during the study

Typical tourists : Research into the theoretical and methodological foundations of a typology of tourism and recreation experiences

Typical tourists are recognisable from a distance. They appear out of place with their loud coloured outfits, often sunburned, walking around loaded with cameras and video-equipment and studying city maps. Yet, tourists are not always all the same. Adventurous eco-tourists, with hiking boots and a good quality daypack, clearly search for a different experience than middle-aged cultural tourists do. Typologies have been developed to classify different groups of tourists and recreationists. However, problems have arisen since the various approaches are quite different and the classification schemes used 'arbitrary'. The question remains "which typology should have preference"? This book reports a long-term project to establish a theoretical and useful approach to develop a typology of experiences for tourism and recreation. The theoretical framework used as a starting point was Eric Cohen's (1979) phenomenology of tourist experiences. The research covers different activities (camping, sight seeing by car, hiking) and settings (nature areas, bungalow parks, Costa Rica, the Netherlands, Southeast Asia), while maintaining a degree of comparison with the theoretical framework adopted for this study. A detailed insight into the methodological aspects of the approach is provided to enable researchers and students alike to use and build upon the methodology and results. The approach is also meant to be a source of inspiration for policy development and planning for a diversified tourist environmen