Search for dissertations about: "seed-quality"
Showing result 1 - 5 of 6 swedish dissertations containing the word seed-quality.
-
1. Reproductive patterns of birches (Betula spp.) in northern Sweden
Abstract : The aim of this thesis was to study patterns of reproduction of Betula pendula and B. pubescens coll. along an altitudinal, coastal-inland, gradient in northern Sweden. The altitudinal variation was related to the distribution of the birch taxa along the gradient. READ MORE
-
2. Pollination processes - maternal and offspring performance
Abstract : Pollination is one of the most important factors determining the reproductive success of plants. This thesis examines processes associated to varying pollination, with focus on plant responses. The first aim was to examine the possibility and constraints for short-term evolution of flower size in Raphanus raphanistrum. READ MORE
-
3. Improved seed handling techniques for Juniperus polycarpos : implications for active restoration of degraded Juniper forests in Iran
Abstract : Juniperus polycarpos (K. Koch) is one of six native juniper forest tree species in Iran whose population size is declining continuously. The ultimate aim of the research presented in this thesis was to increase the regeneration potential of J. READ MORE
-
4. Costs of foraging in a dry tropical environment
Abstract : This study evaluates the costs associated with foraging for birds in a savannah woodland area in central Nigeria. Specifically, it looks at the following questions: 1) how does seasonal variability in food and water availability affect the value of resources to birds in dry environments? 2) Does proximity to water affect foraging decisions? What implication will this have in the management of savannah birds? 3) Are tropical birds mostly affected by metabolic or predation costs? 4) What factors affect diet selection in birds and how? 5) How are birds adapted to hot dry environments? I carried out experiments in the field and in an aviary and provided artificial food patches, consisting of feeding trays with seeds mixed in sand or pebbles (in the aviary study). READ MORE
-
5. Interplay Between Phospholipids and Digalactosyldiacylglycerol in Phosphate Limited Oats
Abstract : Phosphate is an essential nutrient. In most soils it is limiting, which has resulted in that phosphate is supplied as fertilizer to increase crop yield. Through evolution, plants have adapted several mechanisms to increase phosphate uptake from the soil and to household with acquired phosphate. READ MORE