Critical nutrient concentrations and antagonistic and synergistic relationships among the nutrients of NFT‐grown young tomato plants

Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn.     

Some anther structures in Sanguisorba minor Scop. (Rosaceae)

In this study, investigation of some anther structures in Sanguisorba minor Scop. subsp. muricata was aimed. Therefore, anthers were squashed by modified glycerine-gelatine method and additionally different histochemical stainings also were tested. The result illustrated that in different parts of anther, such as marginal, connection tissue, starch and protein granules accumulated. Furthermore, during maturation these deposits were detected in pollen grains also. In addition, a very interesting feature, balloon-like structures filled by proteins, were observed in anther cavity. In the light of these findings, their importance on pollen development was discussed.     

Spread of Tomato spotted wilt virus from an internal virus source by thrips species in Samsun, Turkey

The temporal and spatial distribution of Tomato spotted wilt virus (TSWV) was studied in a 2,085 m² tomato field with a total of 4,080 plants during 10 weeks from 5 July to 6 September in 2004. First infected plants were detected 4 weeks after the source plants were placed in the field and their number continued to increase by week 7. A total of 147 plants (3.6%) were recorded to be infected according to symptom occurrence and serological test by the end of the experiment. Thrips monitoring was carried out from May 25 to October 25 in the same year. Two thrips species, Frankliniella intonsa (Tryborn) and Thrips tabaci (Lindemann), were determined in the experimental area, with the latter one being the more prevalent (84.9%) species. There was a significant correlation (r?=?0.988, P?<?0.01) between the number of thrips species and the number of infected plants in the field. Majority of infected plants were not located near (0–10 m) an internal virus source within the experimental area, whereas 45.6% of the infected plants were located at a distance of 21–30 m. The number of infected plants at a distance of 21–25 m was significantly higher than at all other distances (P?<?0.05). There was no gradual increase in the distances of TSWV-infected plants within 0–30 m as time progressed. The virus seems to be transmitted by vectors through primary infections and scattered within 30-m distance, but limited secondary infections seem likely to occur after this distance in the case of a small internal virus source.     

Determination of genetic diversity in european cranberrybush (Viburnum opulus L.) genotypes based on morphological,phytochemical and ISSR markers

Genetic Resources and Crop Evolution - Turkey has a high diversity of native and commercially grown plants. European cranberrybush, a fruit species grown commercially in the country, is of interest...     

Screw-nail withdrawal and bonding strength of paulownia (Paulownia tomentosa Steud.) wood

The effects of screw type, moisture content, and grain direction on the screw and nail withdrawal strength and bonding strength were investigated for paulownia (Paulownia tomentosa Steud.) wood grown in Turkey. The withdrawal strength was carried out according to the ASTM-D 143 and ASTM-D 1761 and Turkish Standard 6094 in three directions (tangential, radial, and longitudinal) on 60 samples. The moisture content of half of the samples was 12 % and that of the other half 28 %.The experiment of bonding strength (BS EN 205) was applied to both sanded surfaces jointed by poly-vinly acetate and Desmodur-VTKA adhesives. Results of the tests indicate that, the withdrawal strength values at 12 % moisture content were higher than the 28 % for screws whereas the withdrawal strength for 28 % moisture content was higher than 12 % for nails. The maximum withdrawal strength value was found in the chipboard screw. In the case of directions, the withdrawal strength values of radial direction were found to be higher than the others for all parameters. The lowest withdrawal strength values were found in the longitudinal directions for both nails and screws. For adhesive types, the highest bonding strength of D-VTKA was found to be 5.64 N mm^?2 and it was higher than the bonding strength with PVAc (5.33 N mm^?2). However, there were no significant statistical differences between the two adhesive types. The results show that paulownia wood can be used for different purposes such as house construction, roof systems, and box cases as it possesses enough strength.     

Simple sequence repeats as useful resources to study transcribed genes of cotton

Microsatellites or Simple Sequence Repeats(SSRs) are informative molecular genetic markers in many crop species. SSRs are PCR-based, highly polymorphic, abundant, widely distributed throughout the genome and inherited in a co-dominant manner in most cases. Here we describe the presence of SSRs in cDNAs of cotton. Thirty one SSR primer pairs of 220 (∼14%) tested led to PCR amplification of discrete fragments using cotton leaf cDNA as template. Sequence analysis showed 25% of 24randomly selected cDNA clones amplified with different SSR primer pairs contained repeat motifs. We further showed that sequences from the SSR-containing cDNAs were conserved across G. barbadense and G. hirsutum, revealing the importance of the SSR markers for comparative mapping of transcribed genes. Data mining for plant SSR-ESTs from the publicly available databases identified SSRs motifs in many plant species,including cotton, in a range of 1.1 to4.8% of the submitted ESTs for a given species. This revised version was published online in August 2006 with corrections to the Cover Date.     

Comparative analysis of Australian and Canadian barleys for seed dormancy and malting quality

The association between high malting quality and pre-harvest sprouting (PHS) susceptibility is a key challenge when developing new malting barley varieties. A new malting barley variety Baudin has successfully combined high malting quality and PHS tolerance. A doubled haploid population was developed for mapping PHS tolerance and seed dormancy from a cross of Baudin?×?AC Metcalfe using 233 molecular markers. Three QTLs were mapped for seed dormancy based on the standard germination test at 24, 48 and 72?h. One major QTL was mapped to the long arm of chromosome 5H controlling seed dormancy and PHS tolerance from Baudin. Two other minor QTLs were identified from Baudin on chromosomes 3 and 7H. QTL/QTL interaction was detected for seed dormancy between chromosomes 3 and 5H. The PHS tolerance allele of the 5H QTL from Baudin contributes to higher malt yield without significant impact on diastatic power, beta-glucan content and wort viscosity. QTL from Baudin provide new sources to integrate PHS tolerance and high malting quality.