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1.

Salinity affects many areas in our country and around the world, resulting in dramatic reductions in plant yields. In this study, the plant yield, some plant quality parameters, and soil salinity in the plant root area were investigated by irrigating tobacco plants (Nicotiana tabacum L.) with different salinity irrigation waters. The experiment was carried out in pots in 4 replicates according to the randomized plot design. Six different salinity of irrigation water applications were applied in the experiment (S0?=?0.38 dS m?1, S1?=?2 dS m?1, S2?=?5 dS m?1, S3?=?8 dS m?1, S4?=?11 dS m?1, S5?=?15 dS m?1). According to the data obtained at the end of the research, as the salinity of irrigation water increased, plant length, leaf width, leaf length, leaf dry weight and leaf number decreased. It was determined that there was a certain increase in nicotine content in the face of the decrease of all examined physical parameters in irrigation water increase. In addition, the salinity values in the plant root zone soils and the salinity values in the outlet (drainage) water have also increased. Salinity threshold value of the tobacco plant was determined to be 2.04 dS m?1. With an increase in salinity by one unit, there was a 7.1% decrease in leaf dry weight. It was determined that the tobacco plant is vulnerable to salinity based on the data collected.

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2.
Saponins from Argania spinosa at a non-haemolytic concentration diminish by 53.2% erythrocyte haemolysis induced by free radicals. 2 mM aspirin and acetaminophen diminish by 75% and 68% , respectively, erythrocyte haemolysis induced by free radicals, while 0.3 muM vitamin E shows no significant antioxidant activity. Interestingly, a combination of 1 mg/l of A. spinosa saponins and vitamin E at 0.3 muM resulted in a 68% level of protection against free radical-induced erythrocyte haemolysis, which may suggest that A. spinosa saponins enhance the antioxidant effect of vitamin E. In contrast, no synergic effect was observed for acetaminophen (2 mM) when in combination with vitamin E (0.3 muM). These results demonstrate the antioxidant properties of saponins from A. spinosa and their ability to potentate the antioxidant effect of vitamin E.  相似文献   
3.
A feeding trial of 60 days was conducted to delineate the effect of dietary synbiotic on maximum growth, body composition, digestive enzyme activity and subsequently gut microbiota in Cirrhinus mrigala fingerlings. One hundred and eighty acclimatized fingerlings of mrigal with initial body weight ranging from 2.87 ± 0.01 g to 3.26 ± 0.05 g were randomly distributed in three replicates of each of four experimental groups including control (without probiotic and prebiotic), T1 (high probiotic + low prebiotic), T2 (low probiotic + high prebiotic) and T3 (high probiotic + high prebiotic), using completely randomized design (CRD). Results showed that growth performance parameters, such as specific growth rate (SGR), per cent weight gain, feed conversion ratio (FCR) and protein efficiency ratio (PER), were reported to be higher in the T2 group followed by the T3 group. Maximum gut microbiota activity was found in the T3 group which was significantly different from other treatment groups. Similarly, body composition and digestive enzyme activity varied significantly (p < .05) among the treatment groups. The study showed the possibility of improved nutrient utilization in terms of growth performance and digestive enzyme activity in the group following dietary synbiotic supplementation.  相似文献   
4.
M. Mert    S. Kurt    O. Gencer    Y. Akiscan    K. Boyaci  F. M. Tok 《Plant Breeding》2005,124(1):102-104
Verticillium wilt, caused by Verticillium dahliae Kleb., is a major constraint to cotton production in almost all countries where cotton is cultivated. Developing new cotton cultivars resistant to Verticillium wilt is the most effective and feasible way to combat the problem. Little is known about the inheritance of resistance to Verticillium wilt of cotton, especially that caused by the defoliating (D) and nondefoliating (ND) pathotypes of the soil‐borne fungus V. dahliae. The objective of this study was to determine the inheritance of resistance in cotton against both pathotypes of V. dahliae. Crosses were made between the susceptible parent ‘Cukurova 1518’ and each of four resistant parents PAUM 401, PAUM 403, PAUM 405 and PAUM 406 to produce F2 generations in 2002 and F2:3 families in 2003. Disease responses of parent and progeny populations to the D and ND pathotypes were scored based on a scale of 0‐4 (0, resistant; 4, susceptible). F2 populations inoculated with the D pathotype showed a 3 : 1 (resistant : susceptible) plant segregation ratio. Tests of F2:3 families confirmed that resistance was controlled by a single dominant gene. In contrast, analysis of data from F2‐ and F2‐derived F3 families suggested that resistance to the ND pathotype is controlled by dominant alleles at two loci.  相似文献   
5.
6.
The objective of the current study was to characterize Fusarium oxysporum f. sp. radicis-cucumerinum isolates from cucumbers in Turkey in terms of pathogenicity, vegetative compatibility and amplified fragment length polymorphism (AFLP) variation. In the 2007 and 2008 greenhouse cucumber-growing seasons, surveys were conducted in Adana, Antalya, Hatay and Mersin provinces of the Mediterranean region of Turkey. Forty-seven fungal isolates of F. oxysporum were recovered from diseased cucumber plants. The pathogenicity of each isolate was tested on cucumber seedlings at the one-true-leaf stage. Forty of the 47 isolates of F. oxysporum were virulent on cucumber seedlings. Based on disease symptoms, the differential effect of temperatures of 17°C and 29°C on disease development, and the virulence on cucumber seedlings, these 40 isolates were identified as F. oxysporum f. sp. radicis-cucumerinum. Nitrate non-utilizing mutants were generated on minimal medium containing 1.5% KClO3 and their phenotypes were determined. Mutants in different phenotypic classes were paired on minimal medium; of 40 F. oxysporum f. sp. radicis-cucumerinum isolates, thirty-eight were placed into VCG 0260. Remaining two strains were assigned to VCG 0261. The AFLP primers produced a total of 180 fragments between 200 and 500 bp in length for the 30 isolates tested. At a genetic similarity of 0.71, the UPGMA analysis separated the isolates into two distinct clusters. The first cluster, AFLP I, included 28 isolates, of which all belonged to VCG 0260. Two strains in the second AFLP cluster both belonged to VCG 0261.  相似文献   
7.
Secondary endosymbionts of Turkish Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) populations were determined by PCR-based DNA analysis. Experiments were conducted with B. tabaci samples collected from various host plants between 2007 and 2012. Four secondary endosymbionts, namely, Rickettsia, Hamiltonella, Arsenophonus and Wolbachia, were detected from two different B. tabaci species (B and Q). While Arsenophonus and Wolbachia were determined only from the Q, Hamiltonella was found only on the B. Rickettsia was determined on both B and Q. Forty percent of individuals were infected with Arsenophonus, followed by Hamiltonella (32.4 %), and Wolbachia (8 %). Infection rate of Rickettsia was found to be higher on B (29.7 %) than on Q (21.6 %). This study is the first report of endosymbionts of B. tabaci populations collected from Turkey, and studies should be continued to cover larger areas, more host plants and B. tabaci populations.  相似文献   
8.
During 2005 to 2007, eggplant fields in 19 provinces from three different regions (western, southern and southeastern Anatolia regions) of Turkey were surveyed for Verticillium wilt. Sixty-seven isolates of Verticillium dahliae from wilted eggplants were collected and used for vegetative compatibility analysis using nitrate non-utilizing mutants and reference tester strains of vegetative compatibility groups (VCGs) 1A, 2A, 2B, 3, 4A and 4B. Among all isolates, 33 (12 from western, 15 from southern and six from southeastern Anatolia) were assigned to VCG2B, 23 (four from western, eight from southern and 11 from southeastern Anatolia) to VCG2A, six (four from southern, one from western, and one from southeastern Anatolia) to VCG4B and five (one from western, one from southern and three from southeastern Anatolia) to VCG1A, whereas VCG3 and VCG4A were not defined among isolates. In order to test if there is a correlation between VCG and pathogenicity in V. dahliae, pathogenicity of 30 isolates, representing the four multimember VCGs, were tested on Solanum melongena cvs. ‘Kemer’ and ‘Aydın Siyahı’ in an unheated greenhouse. All isolates were found to be pathogenic on both cultivars and there was no difference in susceptibility between the two cultivars. VCG4B isolates collectively led to higher vascular discoloration index (VDI) on both cultivars and higher disease severity index (DSI) on ‘Kemer’ compared with other VCGs. Similarly, VCG1A caused lower VDI on both cultivars and lower DSI on ‘Kemer’. Isolates within each of VCGs 1A, 2A and 4B caused similar VDI on both cultivars. Isolates of VCG2B were found to vary in their VDI values on both cultivars. To the best of our knowledge, the present study is the first report of natural infections of eggplant by VCG1A.  相似文献   
9.
10.

BACKGROUND

1,3,4‐Oxadiazole and imidazolidine rings are important heterocyclic compounds exhibiting a variety of biological activities. In this study, novel compounds with oxadiazole and imidazolidine rings were synthesized from 3‐(methylsulfonyl)‐2‐oxoimidazolidine‐1‐carbonyl chloride and screened for insecticidal activities. The proposed structures of the 17 synthesized compounds were confirmed using elemental analysis, infrared (IR), proton nuclear magnetic resonance (1H‐NMR), and mass spectroscopy.

RESULTS

None of the compounds showed larvicidal activity at the tested concentrations against first‐instar Aedes aegypti larvae. However, nine compounds exhibited promising adulticidal activity, with mortality rates of ≥80% at 5 µg per mosquito. Further dose–response bioassays were undertaken to determine median lethal dose (LD50) values. Compounds 1 , 2b , 2c , 2d , 2 g , 3b , 3c , 3 g, and 3 h were effective, with typical LD50 values of about 5 ? 10 µg per mosquito against female Ae. aegypti. Compounds 2c (bearing a nitro group on the aromatic ring; LD50 = 2.80 ± 0.54 µg per mosquito) and 3 h ( double halogen groups at 2,4 position on the phenyl ring; LD50 = 2.80 ± 0.54 µg per mosquito) were the most promising compounds.

CONCLUSION

Preliminary mode of action studies failed to show consistent evidence of either neurotoxic or mitochondria‐directed effects. Further chemical synthesis within this series may lead to the development of new effective insecticides. © 2017 Society of Chemical Industry
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