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91.
Drought Effect on Grain Number and Grain Weight at Spike and Spikelet Level in Six‐Row Spring Barley
A. Rajala K. Hakala P. Mäkelä P. Peltonen‐Sainio 《Journal of Agronomy and Crop Science》2011,197(2):103-112
Water is the primary regulator of yield formation in cereals. The effect of water limitation and its timing on development of yield components were studied in detail at spike and spikelet level in spring barley (Hordeum vulgare L.). An experiment with three watering treatments (control watering, CONT; drought prior to pollination, DR1 and terminal drought, DR2) was set up in a large greenhouse (20 × 30 m). In addition to watering treatments, two NPK fertilizer application rates (0 and 120 kg N ha?1) were used to investigate the fertilizer effect. The drought effect exceeded the effect of fertilizer application for grain number and single grain weight (SGW). DR1 reduced the number of grains, whereas DR2 reduced both SGW and the number of grains. Resuming the watering at pollination (DR1) restored photosynthesis and enhanced grain filling, resulting in almost similar SGW in DR1 and CONT plants. Spikelets in the upper mid‐section of the spike dominated yield formation in all treatments. This was particularly emphasised in DR1 plants as 58 % of the grain yield was produced in spikelets 3–5, whereas in DR2 and CONT plants it was 39 % and 36 %, respectively. Hence, drought prior pollination strongly reduced yielding capacity (=grain number) in apical and basal spikelets. DR1 and DR2 reduced substantially grain yield and grain N yield resulting in low nitrogen use efficiency. 相似文献
92.
Nurmi A Mursu J Nurmi T Nyyssönen K Alfthan G Hiltunen R Kaikkonen J Salonen JT Voutilainen S 《Journal of agricultural and food chemistry》2006,54(16):5790-5796
Oregano has been shown to possess antioxidant capacity in various in vitro models and has thus been suggested to be potentially beneficial to human health, but studies in humans are lacking. The aim of this study was to investigate the bioavailability and the effects of Origanum vulgare extract supplementation on serum lipids and lipid peroxidation in healthy nonsmoking men. A four-week double-blinded supplementation trial was concluded in which volunteers (n = 45) were randomized to consume daily mango-orange juice (placebo), mango-orange juice enriched with 300 mg/d total phenolic compounds from oregano extract, or mango-orange juice enriched with 600 mg/d total phenolic compounds from oregano extract. The excretion of phenolic compounds was markedly increased in the higher phenolic group as compared to the placebo group, but no significant changes were observed in the safety parameters, serum lipids, or biomarkers of lipid peroxidation. 相似文献
93.
Ali Khosravi Shakib Azizollah Khandan Mirkohi Sepideh Kalate Jari 《Compost science & utilization》2019,27(1):61-68
This study was carried out to evaluate the impact of irrigation regime and potting media on morpho-physiological and biochemical characteristics of pot marigold. The experiment was arranged factorially based on a completely randomized design. The first factor was irrigation regime in three levels of 80, 60 and 40% available water content and the second factor was potting media in five levels of 20% vermicompost, 30% vermicompost, 20% manure compost, 30% manure compost and control (sand and soil in equal proportions). Morpho-physiological traits (plant height, stem diameter, number of flowering stem, root diameter, root length, root dry weight, aerial dry weight, total dry weight, relative water content, ionic stability and water use efficiency) and biochemical traits (malondialdehyde content, catalase and peroxidase activity, chlorophyll and carotenoid contents) were measured. Morpho-physiological parameters, chlorophyll and carotenoid decreased under water deficit, while increased with application of vermicompost and manure compost. Also, lipid peroxidation, catalase and peroxidase activity enhanced under water deficit, while decreased with application of vermicompost and manure compost. In other words, the application of vermicompost and manure compost in potting media reduced the harmful effects of water deficit. Total dry mass and water use efficiency were about 3-fold higher in plants grown in 30% vermicompost or 30% manure compost substrate compared to those in control plants. The results suggest that the application of 30% manure compost could be recommended as suitable potting media due to reducing the negative effects of water shortages, helping to nourish the plant, cheapness and accessibility compared with 30% vermicompost. 相似文献
94.
Matti Sirén Aura Salmivaara Jari Ala-Ilomäki Samuli Launiainen Harri Lindeman Jori Uusitalo 《Scandinavian Journal of Forest Research》2019,34(2):145-154
Predictive factors for forwarder rut formation were studied on fine-grained mineral soils. The study was carried out in southern Finland in mid-May, when the soil water contents were high after snowmelt. A total of 7 study tracks of 20?m were cut with a harvester. After removing the logging residues, a loaded forwarder made 3–4 passes on each track. The forwarder rut depth was related to the total overdriven mass driven over the measurement line, volumetric water content, cone penetration resistance and the harvester rut depth. A total of five mixed-effects models are presented to predict the rut depth. The first model includes the overdriven cumulative mass, volumetric water content of the soil and the cone penetration resistance. As a penetrometer is more of a research tool, the second model includes only the overdriven cumulative mass and water content, factors that can be used in practical planning operations. The remaining three models all include the rut depth after the harvester pass and the overdriven cumulative mass and also include volumetric water content and cone penetration resistance. The model including the rut depth after a harvester pass and the overdriven cumulative mass is a good predictor of the rut depth and supports earlier findings on the connection between harvester and forwarder rut formations. 相似文献
95.
96.
Carabid beetle assemblages (Coleoptera,Carabidae) across urban-rural gradients: an international comparison 总被引:14,自引:0,他引:14
Niemelä Jari Kotze D. Johan Venn Stephen Penev Lyubomir Stoyanov Ivailo Spence John Hartley Dustin de Oca Enrique Montes 《Landscape Ecology》2002,17(5):387-401
We studied communities of carabid beetles in residual forest patchesalong urban-suburban-rural gradients in three cities (Helsinki, Finland; Sofia,Bulgaria and Edmonton, Canada) to examine their responses to urbanisation. OnlyFinnish carabids showed a marked division of community structure along thegradient. In Bulgaria and Canada, carabids did not separate into distincturban,suburban and rural communities. Our results provide some support for thepredictions that species richness will decrease, that opportunistic specieswillgain dominance, and that small-sized species will become more numerous underdisturbance such as that provided by urbanisation. The rather weak and variedresponse of carabids to this disturbance suggests that local factors and theirinteraction are of primary importance for community composition. Occurrence ofreasonably similar carabid communities across the gradient at each of the threelevels of urbanisation suggests that habitat changes commonly associated withurbanisation have not affected the ecological integrity of carabid assemblagesin residual urban forest patches.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
97.
98.
Sepul K. Barua Jari Kuuluvainen Jani Laturi Jussi Uusivuori 《European Journal of Forest Research》2010,129(2):163-172
The effects of profit and land value tax on harvesting decisions of nonindustrial private forest owners are investigated. We use a model of a utility-maximizing forest owner with amenity preferences for timber, which extends the basic two-period harvesting model to include both thinning and clear-cutting harvests. It is demonstrated that with no amenity preference, the profit and land value taxes are neutral to clear-cutting and thinning decisions. Under small to medium amenity preferences, the profit tax decreases the optimal clear-cutting volumes. However, the effect on thinning may be positive or negative, depending on the amenity preference level. The total effect of the profit tax on the short-run timber supply is negative. The effects of the land value tax contrast with those of the profit tax. Also, a tax regime with a lowered profit tax rate combined with a land value tax is analysed. It is shown to be able to bring Pareto-improvement to a regime that uses a higher profit tax but no land value tax. 相似文献
99.
Gap fellings are used to promote multi-cohort structures and to restore other natural forest structures and processes in protected areas that have been altered by anthropogenic activities. Gaps and felled trees may also provide breeding material for species that in high numbers can cause significant tree mortality, growth reduction and consequent economic losses in surrounding production forests. In this study, the effect of restoration gap fellings on feeding intensity of Tomicus spp. (pine shoot beetles) was evaluated by counting fallen pine shoots at different distances from gaps in a protected area in eastern Finland. Gap fellings had a clear effect on the feeding intensity of the beetles. The average density of fallen shoots m−2 was 17 within a 10-m distance from gaps but decreased rapidly to around 4 at the distance of 50 m and beyond. The distance decay in shoot feeding is described well by the negative exponential models. Our results suggest that gap fellings have only a localized effect on shoot feeding by Tomicus in the forests surrounding the restoration gaps. In practical restoration, a buffer zone of 100–200 m around the gap fellings, as implemented here, is enough to minimize economically significant growth reduction in surrounding production forests. As shown in this study, restoration of natural forest structures and dynamics to protect biodiversity is not necessarily in conflict with forest hygiene objectives in production forests. 相似文献
100.
Kaija Saarni Jari Setälä Asmo Honkanen Jarno Virtanen 《Aquaculture Economics & Management (Blackwell Science)》2013,17(5-6):335-343
Abstract In this case study, we describe the evolution of Finnish salmon trout aquaculture; how salmon trout farming grew as a vital industry, how Finland became the world's leading producer of salmon trout, and how the opening of markets to international competition led to a decline of the industry. The focus is on the continuous interaction between the changing market situation and production decisions. The study reveals the impact of national environmental policy on the competitiveness of the industry. At the moment, the industry is undergoing major structural changes; production has moved to neighbouring countries, and the value chain is concentrated. In future, closer interaction and co‐operation between the actors along the entire fish value chain will be the key factors for success. 相似文献