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Ali Fuat Canbolat 《Biological conservation》2004,116(1):81-91
Many parts of the Turkish coastline are important nesting grounds for sea turtles. The aim of this study was to assess the present state of sea turtle populations along the coastline of Turkey, by evaluating research conducted at various nesting grounds from 1979 to 2000. The results of the evaluation indicate that the Turkish coastline is the most important nesting area for Chelonia mydas, and the third most important nesting area for Caretta caretta after Greece and Libya (if nesting estimates for Libya are correct) in the entire Mediterranean. The most important C. caretta nesting beaches in Turkey are Dalyan (11.9%), Kumluca (11.3%), Belek (27.9%), Kizilot, (8.9%) and Anamur (8.8%), while those for C. mydas are Kazanli (24.1%) and Akyatan (54.4%). These sites are classified as “Nesting Areas of 1st Degree Importance”. Annual mean nest numbers along the coastline of Turkey are estimated to be ca. 2000 for C. caretta and 650 for C. mydas. Assuming that each adult female sea turtle nests three times per season, the annual numbers of nesting females along the beaches of Turkey range between about 500 and 800 for C. caretta and 130 and 300 for C. mydas. Annual nesting densities along the 204 km beach strip, which includes 17 important nesting grounds in Turkey, were 11.3 nests/km for C. caretta and 19.2 nests/km for C. mydas. 相似文献
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The bulb onion (Allium cepa L.) was historically seed propagated by open pollination (OP). Cytoplasmic-genic male sterility (CMS) and protandry encourage
outcrossing among individual onion plants. The most common source of CMS in onion is conditioned by the interaction of sterile
(S) cytoplasm with a single nuclear male-fertility restoration (Ms) locus. We previously reported that the majority of OP onion populations possess normal (N) male-fertile cytoplasm and varying
frequencies of the dominant Ms allele. It was unclear why N-cytoplasmic onion populations often possess relatively high frequencies of the Ms allele, which has no obvious function. We used computer simulations to estimate changes in allelic frequencies at Ms for onion populations possessing S-cytoplasm or a mixture of N- and S-cytoplasms, and to determine if frequencies of the
Ms allele stay constant or change due to failure of male gamete production from male-sterile (S msms) plants. The models revealed selection against the recessive ms allele over generations in onion populations possessing S-cytoplasm and varying amounts of self pollination and inbreeding
depression. These models were consistent with field and molecular analyses documenting that N-cytoplasm and the dominant Ms allele predominate in OP onion populations. 相似文献
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Insecticide resistance inHelicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is one of the most important constraints on cotton production in Turkey. We investigated
the susceptibility ofH. armigera strains collected from cotton fields in the Adana, Hatay and Antalya provinces to insecticides which are in wide use. LD50 values for tralomethrin, lambda-cyhalothrin, endosulfan, profenofos and methomyl were determined by topical bioassay. At
the LD50 levels, resistance ratios for tralomethrin were 24.7-, 19.7- and 15.7-fold in the Adana, Hatay, and Antalya strains, respectively;
and for lambda-cyhalothrin were 41-, 20-and 40-fold, respectively. Resistance ratios ranged from 1.2- to 2.1-fold in all field
strains for endosulfan, profenofos and methomyl, with no significant resistance. These results suggest the presence of resistance
to tralomethrin and lambda-cyhalothrin inH. armigera strains collected from cotton fields, but no resistance to endosulfan, profenofos or methomyl could be observed. 相似文献
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The pine processionary moth Thaumetopoea wilkinsoni Tams is a serious pest on pine trees in southwestern Turkey. The efficacy of a naturally derived insecticide, spinosad, on fourth-fifth instar larvae of T. wilkinsoni was studied under laboratory conditions. The product exhibited strong larvicidal activity and at doses above 5 mg litre(-1) caused > 90% mortality in the fourth-fifth larval stages of the species after 72 h. At 72 h the LD50 and LD90 values were 3.26 and 5.69 mg litre(-1) respectively. The results showed that spinosad is highly effective on T. wilkinsoni larvae. 相似文献