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1.
Isik  Fikret  Toplu  Ferit 《New Forests》2004,27(2):175-187
Natural black poplar (Populus nigra L.) clones sampled from river courses were tested in the arid southeast region of Turkey, using a randomized complete block field design with four replications. Clones were laid out in row plots of eight ramets each. Height and apical dominance were assessed at age one year; diameter, survival, bole straightness and branchiness were measured at age two years. Clones differed significantly in survival, growth and quality traits. The results showed that promising clones exist in natural populations. Two commercial clones out of four did not grow as fast as the top new selection clones. For bole straightness, three commercial clones had significantly lower grading scores than the top best 14 clones. Principal components analysis indicated that growth, apical dominance and branching are the most important traits distinguishing black poplar clones. Diameter had a moderate correlation (0.34) with bole straightness. Relationships between geographic variables (elevation, latitude and longitude) with growth and stem quality traits were weak. Considerable genetic variation was observed among clones for all the traits. Genetic differences among the clones accounted for 27% (survival, bole straightness) to 39% (height) of the total variance. Broad-sense individual heritability ranged from 0.27 (survival) to 0.37 (apical dominance). Clonal mean heritabilities were higher than individual heritabilities and ranged from 0.60 (survival) to 0.82 (diameter), implying considerable gain could be realized via selective improvement methods.  相似文献   
2.
The Coruh valley lies within the Caucasus ecological zone, which is considered by the World Wild Fund for Nature and by Conservation International as a one of the biodiversity hotspot in the world. The valley is also recognized by Turkish conservation organizations as an important plant area, an important bird area, a key biodiversity area and has been nominated as a high priority area for protection. This valley is rich in plants and contains 104 nationally threatened plant species of which 67 are endemic to Turkey. Fig (Ficus carica L.) is one of the most important wild edible fruit tree along with pomegranate and olive in the valley. Figs have been used for fresh consumption for centuries and also an important element of natural landscape of the valley. The valley abundantly has black, purple and yellow-green fruited fig trees. In this study we determined some important tree, leaf and fruit morphological characteristics of 50 selected wild grown fig accessions naturally found in the valley. The results showed that the investigated morphological traits of fig accessions displayed significant differences each other. Principal coordinate analysis showed that diversity among the accessions was high and the accessions had black and yellow-green colored fruits were the most diverse groups.  相似文献   
3.
In this study, roes obtained from carp (Cyprinus carpio carpio) that were caught in Keban Dam Lake (Turkey) and cultured rainbow trout (Oncorhynchus mykiss) were processed as caviar, and the products were stored at + 4 C°. Lipid peroxidation and the compositions of fatty acids of these products were assessed during production and storage period. The result of fatty analyses showed that palmitic acid (16:0), stearic acid (18:0), palmitoleic acid (16:1), oleic acid (18:1), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), which are all essential fatty acids, were determined in the caviars of the roes obtained from rainbow trout and carp. According to results of chemical analyses, there were no significant differences in thiobarbituric acid reactive substances (TBARs) between rainbow trout and carp caviars (p > 0.05), but malondialdehyde (MDA) levels were found to be statistically significant (p < 0.01). It can be concluded that caviars obtained from both rainbow trout and carp roes are rich in fatty acids and take a part in a balanced and healthy diet.  相似文献   
4.
5.
Mating system parameters and pollen contamination were estimated in an 11-year-old Pinus brutia Ten. clonal seed orchard, located in Antalya, Turkey, with the aid of isozymes. Isozyme analysis was performed on both maternal (megagametophyte) and embryo tissues of seeds collected from the seed orchard and the surrounding natural stand. Fourteen loci encoding nine enzyme systems were assayed. Based on a multilocus estimator, the proportion of viable seeds originating from outcrossing (tˆm) in the seed orchard was found to be 0.947; the remainder (0.053) was due to selfing. We estimated that 85.7% of the orchard seed resulted from pollen contamination by trees in surrounding stands. This may be related to the young age and subsequent low pollen production of the orchard. Only 9% [i.e., 1.0−0.857 (contamination)−0.053 (selfing) = 0.090] of the orchard offspring was due to cross-pollination among clones within the orchard. Due to the high level of pollen contamination, it is estimated that genetic gain in this seed crop is less than 57% of that expected if all offspring resulted from random mating among orchard clones (i.e., no contamination).  相似文献   
6.

• Background   

Tree breeders have been reluctant to include wood traits in tree improvement programs owing to logistic difficulties and the cost associated with the assessing the traits.  相似文献   
7.
BACKGROUND: Aedes (Stegomyia) albopictus (Skuse), the Asian tiger mosquito, is an introduced invasive species in the United States that is responsible for a significant proportion of service requests to local mosquito control programs. This container‐utilizing mosquito is refractory to standard mosquito abatement measures in the United States. This study is part of a USDA‐ARS project to develop an area‐wide management strategy for Ae. albopictus. The goal was to identify three study sites, similar in socioeconomic parameters, geography and Ae. albopictus abundance, in urban and suburban areas in Mercer and Monmouth counties in New Jersey. Prior service requests and light trap counts and also detailed county maps were used to chose nine preliminary sites (four in Mercer and five in Monmouth) where weekly surveillance for Ae. albopictus was performed throughout the 2008 active season. RESULTS: Although outliers were detected, socioeconomic variables in the study sites within each county were fairly consistent. Ae. albopictus abundance was associated with poverty levels and had the highest maxima in Mercer, although average mosquito abundance was similar in urban Mercer and suburban Monmouth. CONCLUSION: Three study sites in each county were identified for future studies. The summer‐long surveillance also revealed socioeconomic variables critical for the development of integrated mosquito management. Copyright © 2011 Society of Chemical Industry  相似文献   
8.
9.
Çoban  Nermin  Öztürk  Ahmet 《Erwerbs-Obstbau》2022,64(2):229-235

In modern pear cultivation, clonal quince and pear rootstocks are preferred because they are easy to maintain and harvest. Also, they form dwarf plants and improve fruit quality compared to pear seedling rootstocks. However, graft incompatibility can be involved between different species or genera. The aim of the study was to determine the graft compatibility of the ‘Deveci’ and ‘Williams’ pear cultivars with different pear and quince rootstocks by carbohydrate analysis. Carbohydrate accumulation in the graft union was also observed with iodized potassium iodide (KI) staining. In terms of rootstocks, there were no differences in starch and carbohydrate content, but statistically differences were found in sugar contents. Significant differences were also found between cultivars and graft union in terms of the examined traits. Sugar content was highest in OHxF 333 and lowest in seedling rootstocks. There were no statistical differences in the starch content between the graft unions of the ‘Deveci’ cultivar, while starch accumulation was higher above the graft union than below and graft union in the ‘Williams’ cultivar grafted on the quince rootstock. In the study, it was determined that there were higher carbohydrate accumulation in the scion and graft union than below the graft union in ‘Williams’ grafted quince rootstocks, which was also confirmed by staining with KI. As a result of the study, it was concluded that carbohydrate accumulation analysis can be used to determine the graft compatibility of the pear cultivars with the different quince and pear rootstocks.

  相似文献   
10.
Abstract

Biochar is a pyrolyzed biomass produced under limited oxygen or oxygen absent conditions. Few investigations have been conducted to determine the combined effect of biochar with chemical fertilizer on growth, yield and nutrient distribution pattern in root, shoot and grain in wheat as well as changes in soil physiochemical properties. This research was designed to study the combined effect of chemical fertilizer and rice straw-derived biochar on soil physio-chemical properties, growth, yield and nutrient distribution pattern within wheat plant tissue and grain. Results showed that rice straw biochar caused a significant decrease in soil pH and increase in soil organic matter as well as nutrients like total nitrogen (TN), potassium (K), magnesium (Mg) and boron (B) due to incubation. Result also showed that root biomass and straw did not differ between Bangladesh Agricultural Research Council (BARC) and ½ BARC?+?rice straw biochar treatment. Similarly, thousand grain weight and grain yield did not differ between the same treatments. The phosphorus concentration in wheat grain was highest in ½ BARC?+?rice straw biochar as compared to other treatments. The use of rice straw biochar in addition to the chemical fertilizers in wheat production systems is an economically feasible and practical nutrient management practice. Our findings urged that reduction of chemical fertilizer application is possible with supplementation of rice straw biochar.  相似文献   
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