No description available.

No description available.

Investigations were carried out to determine the effect of ecological factors on the induction of diapause in the spruce budworm. Experimental rearings were conducted at elevations of 2500, 4200 and 4750 feet. The foliage of spruce, Douglas fir and alpine fir were used as hosts. Progeny of Ontario, two-year and one-year types reared under one-year and two-year life cycle conditions were used as experimental insects. A trend was observed in emergence from hibernation with the one-year type leading, followed by the two-year and finally the Ontario type. It was shown that the one-year type larvae may adopt the two-year habit. The main factor influencing this is a prolonged development period for the parents. The larvae reared at the higher elevations showed a greater proportion entering diapause. Food played a smaller role with spruce and Douglas fir being more favourable for diapause than alpine fir. The increased percentage of larvae in diapause in 1952 is attributed to a longer development period for their parents and to a sharp drop in temperature occurring about 12 days prior to diapause. The Ontario material may adopt the two-year habit. The factors contributing to this have not been clearly shown as the rearing results are inconclusive. There were no definite differences shown in the time for development among the three foods. The insects at the lowest station developed in approximately three weeks less time than at the highest. The difference between the upper stations was slight. The impracticability of converting a one-year life cycle population to a two-year cycle by forest management is noted. The diapause theories of Wigglesworth and Andrewartha are commented on. A possible course of evolution leading to the establishment of a two-year life cycle population is given. / Science, Faculty of / Zoology, Department of / Graduate

In the region of Lillooet, B.C. a small population of spruce budworm, Ohoristoneura fumiferana (Clem.), has maintained a relatively constant sub-epidemic level for several decades, feeding on Douglas fir, Pseudotsuga taxifolia (Poir.) Britt. No tree mortality has occurred. This population has been under observation for ten years, and it is apparent that an effective natural control complex is operating in the area. Spiders are prominent among the predators of insects in the region. Field observations revealed that many spiders captured both larvae and moths of the spruce budworm. A collection of arboreal spiders of the region was made and identified. Feeding tests were conducted with spiders to determine the budworm-feeding species. Both caged and free spiders were tested. Population samples were taken to determine the relative abundance of spider species in the area, and to discover any differences that may exist between spider populations in the infested forest and in the non-infested forest. Four families were found to comprise eighty percent of the arboreal spiders of the Lillooet district, and seventy percent consisted of only two families, the Thomisidae and the Salticidae. The Thomisids do not capture spruce budworm larvae, but may capture moths. The Salticids capture both larvae and moths. Families Argiopidae and Theridiidae occasionally capture larvae and frequently capture moths. No difference was demonstrated between spider populations in the infested forest and the non-infested forest. / Forestry, Faculty of / Graduate

Vår studie behandlar lagrum, praxis och doktrin gällande budgivningsprocessen i Sverige och huruvida de olika delarna i denna process bidrar till transparens. I Sverige fungerar budgivningen som i en auktion och bud är inte bindande förrän formkraven är uppfyllda, dessa finns i Jordabalken 4:1 för fastigheter och i Bostadsrättslagen 6:4 gällande bostadsrätter. Att bud inte är bindande, är i jämförelse med andra närliggande länder till Sverige, väldigt unikt. Vilket gör att den svenska budgivningsprocessen har många problem som behöver diskuteras och lyftas fram. När vi undersöker transparensen så tar vi i beaktning köpare, säljare, mäklare och spekulanter som inte blir den slutlige köparen och även det svenska samhället i stort. Framförallt fokuserar vi på de olika delarna där vi tycker oss finna mest problem ur ett transparensperspektiv. Dessa delarna är anbudsförteckning, redovisning av bud på nätet, falska bud och slutligen dolda bud. Det vi kommer fram till är att det finns uppenbara transparensproblem i samtliga delar som vi fokuserat på. Framförallt anser vi att anbudsförteckningen är ett bra verktyg för transparens men utnyttjas inte till sin fulla potential. Samma gäller för redovisning av bud på nätet. Där en möjlighet till god transparens för potentiella köpare förstörs av bristande praxis och frånvaro av lagrum. Vi kommer också fram till att falska bud är förödande för mäklakåren, köpare och samhället i stort. Då det både är svårt att upptäcka och svårt att bevisa i domstol så menar vi att det är en tydlig indikation av att transparensen är undermålig och att en förändring behövs för att få bukt med detta. Dolda bud är helt acceptabelt i budgivningar. Det är dock värt att nämna här att FMI rekommenderar öppen budgivning men det är endast en rekommendation. Dolda bud skapar ofta mycket missnöje då transparensen för en spekulant i denna delen är minimal. Vi kommer fram till att dolda bud borde regleras eller helt förbjudas då det skapar mycket missnöje och hat i budgivningar. / Our study address laws, judicial decisions and doctrine about the Swedish bidding process and if the different parts in this process contributes to transparency. In Sweden the biding works like an auction and the bids are not legally binding until the contract is signed, this is regulated by Jordabalken 4:1 for property and in Bostadsrättslagen 6:4 for co-operative apartments. The fact that bids are not legally binding is unique for Sweden in comparison to neighboring countries. However, this causes the Swedish bidding process to have a lot of problems that needs to be discussed. When we investigate the transparency, we take into consideration different perspectives and these are the buyer, the seller, the broker, other possible buyers and the society at large. Mainly we focus on the different parts in the biding process where we think that we find the most problems from a transparency perspective. These parts are the biding list, presentation of bids online, false bids and finally hidden bids. Our conclusions are that there are obvious transparency problems in all the parts that we choose to focus on. We believe that bid list is a great tool for transparency, but it is not used to its full potential. We also believe that the same goes for presentation of bids online. Where there is a possibility for great transparency for potential buyers, but this transparency is destroyed by lack of judicial decisions and laws. We also come to the conclusion that false bids are devastating for the brokers but also the buyers and the society at large. False bids are both hard to notice and hard to prove in court, we believe that this is a strong indication that the transparency is lacking and that a change is needed to make it stop. Hidden bids are completely acceptable in the biding process. It is worth mentioning that FMI recommends an open bidding process but that is just a recommendation. Hidden bids often create a lot of dissatisfied potential buyers because the transparency in a hidden bidding process is minimal. Our conclusion about this is that hidden bids should be regulated or totally forbidden because of how much dissatisfaction and hate it creates in the biding process.

No description available.

Zugl.: Mainz, Univ., Magisterarbeit, 2005

Zugl.: Mainz, Univ., Magisterarbeit, 2005.

Sugar Maple (Acer saccharum Marsh.) is a very important tree species and is known not only for its sap in the production of maple syrup, but also for its superior hardwood quality and popular ornamental properties. In the effort to improve the diversity of the hardwood tree species in Manitoba, an effective propagation method for sugar maple is needed. The study tested several propagation techniques namely in vitro shoot organogenesis, induced embryo conversion and rooting of greenwood cuttings. Shoot multiplication was achieved using bud and embryo explants, however the rate of shoot production was very low implying that the culture conditions required some optimizations. Dormant isolated embryos were induced to germinate and convert into whole plants in vitro, eliminating the need for long stratification period. The study found the highest embryo conversion frequencies by the addition of cytokinin 6-benzylaminopurine (BAP) at 0.5-1.5 mg/L or thidiazuron (TDZ) at 0.01 mg/L into the culture medium. Greenwood cuttings of several hardy cultivars, including ‘Jefcan’, ‘Bailsta’ and ‘Green Mountain’ were compared for rooting capacity. In 2008, cutting type, rooting hormone and collection time were found to significantly influence rooting. In the following year, the study was expanded to compare different rooting conditions, using peat-perlite mix in fog system, sand beds under intermittent misting, and commercial peat plugs under automated misting system. Rooting was improved by selecting for medial-type cuttings and by promoting cutting survival through the the use of peat-based rooting medium and the maintenance of cool temperatures during the rooting period. The application of auxin did not increase rooting frequency of ‘Jefcan’ cuttings, but considerably improved the quality of roots produced, which may affect cutting survival upon transplantation.

Sugar Maple (Acer saccharum Marsh.) is a very important tree species and is known not only for its sap in the production of maple syrup, but also for its superior hardwood quality and popular ornamental properties. In the effort to improve the diversity of the hardwood tree species in Manitoba, an effective propagation method for sugar maple is needed. The study tested several propagation techniques namely in vitro shoot organogenesis, induced embryo conversion and rooting of greenwood cuttings. Shoot multiplication was achieved using bud and embryo explants, however the rate of shoot production was very low implying that the culture conditions required some optimizations. Dormant isolated embryos were induced to germinate and convert into whole plants in vitro, eliminating the need for long stratification period. The study found the highest embryo conversion frequencies by the addition of cytokinin 6-benzylaminopurine (BAP) at 0.5-1.5 mg/L or thidiazuron (TDZ) at 0.01 mg/L into the culture medium. Greenwood cuttings of several hardy cultivars, including ‘Jefcan’, ‘Bailsta’ and ‘Green Mountain’ were compared for rooting capacity. In 2008, cutting type, rooting hormone and collection time were found to significantly influence rooting. In the following year, the study was expanded to compare different rooting conditions, using peat-perlite mix in fog system, sand beds under intermittent misting, and commercial peat plugs under automated misting system. Rooting was improved by selecting for medial-type cuttings and by promoting cutting survival through the the use of peat-based rooting medium and the maintenance of cool temperatures during the rooting period. The application of auxin did not increase rooting frequency of ‘Jefcan’ cuttings, but considerably improved the quality of roots produced, which may affect cutting survival upon transplantation.