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991.
Peroxidase plays important roles in many stress-related interactions and catalyzes important reactions in various physiological processes. Since peroxidase played critical roles in the evolution of almond(Prunus dulcis Miller(D.A Webb) syn P. amygdalus Batsch), peroxidase-gene-based analyses may increase the understanding of evolution of this species. Peroxidase gene polymorphism(POGP) markers were used to determine genetic diversity and relationships among 69 Turkish genotypes/cultivars and 27 foreign almond cultivars by using unweighted pair group method with arithmetic mean(UPGMA) analysis. This study is the first evaluation of the use of POGP markers for diversity analysis in almond.Totally, 83 fragments were obtained from eight peroxidase primer pairs, and polymorphism was identified as 94 %.Similarity level among the genotypes ranged between 0.63 and 0.93, and all materials were distinguished. In general,Turkish and foreign genotypes were mixed in clusters since they share a common genetic background and gene migration among the sites. Clusters were not based on geographic regions except for some minor groupings. This study indicated that peroxidase gene markers can be reliably used to determine genetic relationships in almonds. 相似文献
992.
V. Geissen R. -Y. Kim A. Schning St. Schütte G. W. Brümmer 《Forest Ecology and Management》2003,180(1-3):75-83
We investigated the initial effects of strip wise soil loosening (0–35 cm depth) on soil chemical and physical parameters by using a deeply working rotary cultivator in combination with liming and mixing of the dolomite with the soil material of acidic forests. The investigations took place 8 months after the treatment. pH values and contents of exchangeable Ca and Mg increased significantly at the tilled depth whereas the content of exchangeable Al and easily soluble P decreased. The rate of mineralisation increased at this depth which was shown by a loss of Corg, Ntot and short-term loss of NO3-N. The treatment led to a mobilisation of Mn at the tilled depth. However, the content of exchangeable Pb decreased due to an increased pH value. Below the tillage depth of 35 cm only partly significant changes of exchangeable Mn and NO3-N were found. The total porosity and bulk density at 10–15 and 40–45 cm depths were not significantly different from those in the control plot, but the rate of infiltration increased significantly. 相似文献
993.
FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological,
economic and social issues at the landscape scale. This issue ofSmall-scale Forest Economics, Management and Policy describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the
lessons learned.
The idea to construct and use landscape-scale models of the forest frontier, based on simulating household decisions and land
use at a spatial scale close to the field level, arose from a desire to add rigour to land-use policy research at CIFOR, the
Center for International Forestry Research (Vanclay 1995). This simulation modelling approach to addressing interdisciplinary
issues, where people are strongly interacting with forest resources, became known as FLORES, the Forest Land Oriented Resource
Envisioning System (Vanclay 1998). Muetzelfeldtet al. (1998) constructed a simple prototype of a FLORES model to illustrate the concept and demonstrate the ability of a system-dynamics
modelling environment to animate such a model (Muetzelfeldt and Taylor 1997, 2001, Muetzelfeldt and Massheder 2003). In 1999,
FLORES became a reality, when 50 scientists from diverse disciplines met in Bukittinggi, Indonesia to construct the first
FLORES model styled on this prototype (CIFOR 1999, Vanclayet al. 2003).
The research reported in this special issue was made possible by generous financial support from the Department for International
Development (UK), the European Community, the Asian Development Bank (under RETA 5812) and the Center for International Forestry
Research. The views expressed herein are those of the authors alone. We would like to thank the following people who have
assisted in the production of this special issue by acting as anonymous referees for these and other papers: Andy Warner,
Brendan Moran, Bruno Verbist, Chris Dake, Chris Legg, Doug Sheil, Euan Mason, Francois Bousquet, Frank Vanclay, Geoff Slaughter,
James Gambiza, John Herbohn, John Poulsen, Jungho Suh, Mike Spilsbury, Paul Phillips, Paul van Gardingen, Phil Norman, Philip
Nyhus, Roger Wheate, Ross Sigley, Steve Harrison and Tom Evans. Thanks also to the editorial staff, especially Steve Harrison,
John Herbohn and Jungho Suh, for making this special issue possible. 相似文献
994.
Lahti M Aphalo PJ Finér L Lehto T Leinonen I Mannerkoski H Ryyppö A 《Tree physiology》2002,22(18):1311-1316
Five-year-old Norway spruce (Picea abies (L.) Karst.) seedlings were subjected to three simulated growing seasons in controlled environment chambers. Plants were acclimated to a soil temperature of 16 degrees C during the first and third growing seasons, but were allocated at random to soil temperature treatments of 9, 13, 18 and 21 degrees C during the second growing season. Low soil temperature during the second growing season depressed stomatal conductance and photosynthetic rate (A) per unit of projected leaf area, although intercellular CO2 concentrations did not differ significantly between treatments. At all soil temperatures, total chlorophyll concentration first decreased and then increased, although the rate of increase and the final concentration increased with soil temperature, which may explain the effect of soil temperature on A. Neither chlorophyll a/b ratio nor leaf nitrogen concentration was significantly affected by soil temperature. Treatment differences disappeared during the third simulated growing season when plants were again acclimated to a soil temperature of 16 degrees C. 相似文献
995.
We studied the influence of temperature and near- and sub- optimal mineral nutrition of black spruce seedlings (Picea mariana [Mill.] B.S.P.) during their second growing period on bud set, bud development, growth, mineral content and cold tolerance. Bud break and growth after bud break were also studied. Seedlings were grown for 106 d in growth chambers under three temperature regimes in combination with three concentrations of a fertilizer. They were then cold hardened for 56 d and dehardened for 66 d.Under these near- and sub-optimal N levels, bud formation occurred during the growing season. Bud formation was accelerated with decreasing fertilization, but was not affected by temperature treatments. Needles from seedlings with 0.64% N (dry mass basis) before hardening did not harden. Those with 0.87% N showed a lesser degree of hardiness than those with 1.28% N. Stem diameter increased at the beginning of the hardening period. During this acclimation period, shoot dry mass decreased with time at a constant rate and at the same rate over time for all treatments whereas root dry mass was more variable. Total number of needle primordia was low and no difference was observed among growing conditions. Bud break was similar in all treatments. Following bud break, shoot height and stem diameter increases were small but their magnitude varied with the nutritional regimes applied during the previous growing period. During hardening, nitrogen concentration of shoot tissues first increased and then decreased; phosphorus concentration first increased and then remained stable; potassium concentration remained stable. Concentration of these three elements generally decreased in the roots during this hardening. 相似文献
996.
A survey of forestry practices and attitudes was undertaken in four communities in Leyte, the Philippines, to improve understanding
of the social and economic factors affecting small-scale forestry development. The survey had three main data collection activities
— initial focus group discussions (FGDs), household interviews, and reporting and validation FGDs. A team of enumerators was
selected for household interviews which consisted of both males and females, to avoid potential problems of unwillingness
of people to talk with those of the opposite gender. The interviewers were also required to be able to speak local dialects
(Cebuano and Waray Waray), the survey questionnaires being administered in these dialects. Various methods were used to gain
the support and assistance of local government units and barangay captains. Some difficulty was experienced by the survey
team in the first community due to barangay elections at the time of the survey, and the requirement by the University of
Queensland Ethics Committee that respondents sign a consent form. This requirement was found to be not culturally appropriate
for the Leyte smallholder communities. Offering goods at the end of the interview was found to be of limited value for encouraging
participation in the survey. Provision of food and drinks were found to encourage FGD participants to express their views,
but too much alcohol had a negative effect. The importance of providing comprehensive feedback to respondents and involving
them and other stakeholders in development of policy recommendations was apparent. These survey experiences provide valuable
insights which are not generally available in textbooks on sample surveys, and provide lessons for planning and conducting
smallholder community survey into natural resource management issues. 相似文献
997.
We characterized the adventitious rooting response of Eucalyptus globulus Labill. to various concentrations of calcium, nitrogen, phosphorus, iron, manganese, zinc, boron and copper. The parameters analyzed were percent rooting, root number, root length and mean rooting time. Root number and root length were significantly affected by mineral nutrition, whereas mean rooting time and rooting percentage seemed to be closely related to auxin availability. Root number was affected by calcium, nitrogen source and zinc, whereas root length was influenced by concentrations of phosphorus, iron and manganese, and by nitrogen source. Based on these results, we evaluated various combinations of several concentrations of these minerals in each rooting phase. Cuttings that were rooted in an optimized mineral nutrient medium and acclimatized to ex-vitro conditions for two months showed significantly higher survival after transplanting and drought stress than cuttings rooted in basal medium and treated in the same way. 相似文献
998.
Rauter AP Filipe MM Prata C Noronha JP Sampayo MA Justino J Bermejo J 《Fitoterapia》2005,76(5):433-438
Diacronema sp. was cultured and its sterols were separated by column chromatography on silica gel. The new sterol 24-ethyl-4alpha-methyl-cholestane-3,20-diol (1) was characterised by NMR and MS spectrometry, as well as (22E)-24-ethyl-4alpha-methyl-5alpha-cholest-22-en-3beta-ol (2) and beta-sitosterol, the major components of the sterol fractions. Neither the biosynthetic origin of the new dihydroxysterol nor its role in the biochemistry of Diacronema is known. 相似文献
999.
The spectral data of a new Δ7,22 sterol, 24S-ethyl-5α-cholesta-7,22E-dien-3α-ol β-galactopyranoside, isolated from the bulbs of Autonoë madeirensis, are reported. 相似文献
1000.
Forest commons are regarded as a means to support local development and sustainable forest conditions. To evaluate the development
impact of Swedish forest commons, comparative surveys have been undertaken in three regions, and the differences in forest
condition and management between categories of commons as well as their relation to other forest ownerships have been assessed.
Regional differences between the by-laws, historical development and geographical conditions are apparent. It is concluded
that two of three regions have an overly restrictive harvesting policy given the purpose of the forest commons and the official
forest policy. The study results underline the importance of evaluation of the performance of forest management in relation
to management objectives, to ownership alternatives and to the impact of local variations in preconditions. 相似文献