Deficit water treatment studies and some practices to reduce the effects of drought on plant can ... more Deficit water treatment studies and some practices to reduce the effects of drought on plant can be made in Mediterranean region. Therefore the study was carried out at three different supplies as non-fertilization, standard fertilization [210 kg.ha -1 pure N, 60 kg.ha -1 pure P, 60 kg.ha -1 pure K (NH4NO3, P2O5 and K2O – 60 kg.ha -1 with 15-1515 composite before planting and H 2NCONH2 – 150 kg.ha -1 with urea before first water)] and extra potassium (standard fertilization +60 kg.ha -1 K 2SO4) and three irrigation doses (500 mm, 400 mm and 300 mm) during development stages [(8 leaf stage (V8), before Tasselling (VT), after blister, milk stage and dough stage)] in the Aegean region of Turkey during 2013 summer growth periods. The experiment was a randomized block design with three replications. 31G98, 31D24 and NK-Arma corn cultivars were used to material of the experiment. Seed yield and some yield components such as cob length, the number of seed per cob and 1000 seed weight were ...
Drought stress is one of the most limiting factors in agricultural productivity because of its hi... more Drought stress is one of the most limiting factors in agricultural productivity because of its highly negative effect on photosynthesis and growth of plants. The main objectives of this study were to determine the performance of four selected safflower genotypes (Remzibey, Dinçer, Balcı and TRE-ASL09/14) against drought stress. The relationship between water use efficiency (WUE) and δ13C (isotope discrimination) was investigated under well watered (60%) and drought stress (30%) irrigation in controlled conditions in a green house. The result showed that drought stress clearly reduced plant biomass, leaf area, leaf number, relative water content (RWC), specific leaf weight (SLW), WUE and δ13C in all genotypes, while chlorophyll increased under drought stress. There were significant differences between performances of all safflower genotypes in terms of response to drought stress. High WUE and low δ13C discrimination under drought stress were inversely associated with a strong regression relationship (R2=0.75). The analysis of δ13C revealed a substantial variation in water use efficiency among the genotypes under drought stress. It was revealed that low δ13C discrimination types had high WUE, RWC and total biomass under drought stress. Thus, the ability of the low δ13C genotypes (high water use efficiency, WUE) to maintain higher RWC may provide a good indication of the differences in drought tolerance of safflower genotypes differing in δ13C. Overall, on the basis of the consistent percentage reductions in plant heights, total dry weight, leaf area, RWC, WUE and low δ13C, the TRE-ASL09/14 new breeding line was found to be more drought tolerant when compared with the other safflower hybrids under drought stress. As a result of our study it is suggested that there is a strong relationship between WUE and lower δ13C under drought stress, indicating that it may be used as a selection criterion for developing safflower genotypes with drought tolerance.
Turkey has applied for EU-membership, but still faces problems of lacking quality standards for b... more Turkey has applied for EU-membership, but still faces problems of lacking quality standards for bread wheat. Studies on the infl uence of S-fertilization on grain yield and bread-making quality of wheat (Triticum aestivum L.) in the region haven't been carried out until today. This research was conducted for two growing seasons (at Adnan Menderes University Research and Experimental Farm located in the Western Turkey (Aegean region) at 37º 44' N 27º 44' E in order to determine the effects of nitrogen (0, 70, 140, 210 kg ha -1 ) supplemented with sulphur (0 or 40 kg ha -1 ) with respect to yield and bread-making quality of the varieties Golia and Sagittario, grown primarily in Western Turkey. S-fertilization had positive effects on grain yield and some quality parameters under Mediterranean conditions; however, signifi cant differencess were rather rare. Particularly the gluten-index and the sedimentation value promoted by S fertilization were among the tested parameters. Therefore, S-fertilization in improving bread-making quality of wheat in the region should not be disregarded. Grain yield and quality could be promoted simultaneously with increasing N-doses.
Sowing date is an important factor to change of maize (Zea mays L.) yield in temperate zone. Dela... more Sowing date is an important factor to change of maize (Zea mays L.) yield in temperate zone. Delay to sowing change to temperature for during the growth period. Crop could be damage for high temperature in some critical period (seedling, grain filling). The objective of this study is determination of sowing date effect on yield, dry matter accumulation, leaf area index and some growth parameters in maize crops. Two experiments were conducted in the experiment from 2005 to 2006 with two maize hybrids (31G98 32K61). The treatments consisted of different sowing dates. Cob yield, dry matter accumulations, leaf area index (LAI), net assimilation rate (NAR) and crop growth rate (CGR) was measured. The result of the study there was no significant differences among of the varieties in cob yield. The first year the maximum dry matter yield was obtained 31G98 to the first sowing date. Optimum LAI values showed the same variety in the same production period. The second sowing date in the first year of the highest dry matter yield varieties gave 32K61. NAR and CGR curves obtained gave similar values. The first product resulting from the NAR and CGR curves has more stable than the second product.
Deficit water treatment studies and some practices to reduce the effects of drought on plant can ... more Deficit water treatment studies and some practices to reduce the effects of drought on plant can be made in Mediterranean region. Therefore the study was carried out at three different supplies as non-fertilization, standard fertilization [210 kg.ha -1 pure N, 60 kg.ha -1 pure P, 60 kg.ha -1 pure K (NH4NO3, P2O5 and K2O – 60 kg.ha -1 with 15-1515 composite before planting and H 2NCONH2 – 150 kg.ha -1 with urea before first water)] and extra potassium (standard fertilization +60 kg.ha -1 K 2SO4) and three irrigation doses (500 mm, 400 mm and 300 mm) during development stages [(8 leaf stage (V8), before Tasselling (VT), after blister, milk stage and dough stage)] in the Aegean region of Turkey during 2013 summer growth periods. The experiment was a randomized block design with three replications. 31G98, 31D24 and NK-Arma corn cultivars were used to material of the experiment. Seed yield and some yield components such as cob length, the number of seed per cob and 1000 seed weight were ...
Drought stress is one of the most limiting factors in agricultural productivity because of its hi... more Drought stress is one of the most limiting factors in agricultural productivity because of its highly negative effect on photosynthesis and growth of plants. The main objectives of this study were to determine the performance of four selected safflower genotypes (Remzibey, Dinçer, Balcı and TRE-ASL09/14) against drought stress. The relationship between water use efficiency (WUE) and δ13C (isotope discrimination) was investigated under well watered (60%) and drought stress (30%) irrigation in controlled conditions in a green house. The result showed that drought stress clearly reduced plant biomass, leaf area, leaf number, relative water content (RWC), specific leaf weight (SLW), WUE and δ13C in all genotypes, while chlorophyll increased under drought stress. There were significant differences between performances of all safflower genotypes in terms of response to drought stress. High WUE and low δ13C discrimination under drought stress were inversely associated with a strong regression relationship (R2=0.75). The analysis of δ13C revealed a substantial variation in water use efficiency among the genotypes under drought stress. It was revealed that low δ13C discrimination types had high WUE, RWC and total biomass under drought stress. Thus, the ability of the low δ13C genotypes (high water use efficiency, WUE) to maintain higher RWC may provide a good indication of the differences in drought tolerance of safflower genotypes differing in δ13C. Overall, on the basis of the consistent percentage reductions in plant heights, total dry weight, leaf area, RWC, WUE and low δ13C, the TRE-ASL09/14 new breeding line was found to be more drought tolerant when compared with the other safflower hybrids under drought stress. As a result of our study it is suggested that there is a strong relationship between WUE and lower δ13C under drought stress, indicating that it may be used as a selection criterion for developing safflower genotypes with drought tolerance.
Turkey has applied for EU-membership, but still faces problems of lacking quality standards for b... more Turkey has applied for EU-membership, but still faces problems of lacking quality standards for bread wheat. Studies on the infl uence of S-fertilization on grain yield and bread-making quality of wheat (Triticum aestivum L.) in the region haven't been carried out until today. This research was conducted for two growing seasons (at Adnan Menderes University Research and Experimental Farm located in the Western Turkey (Aegean region) at 37º 44' N 27º 44' E in order to determine the effects of nitrogen (0, 70, 140, 210 kg ha -1 ) supplemented with sulphur (0 or 40 kg ha -1 ) with respect to yield and bread-making quality of the varieties Golia and Sagittario, grown primarily in Western Turkey. S-fertilization had positive effects on grain yield and some quality parameters under Mediterranean conditions; however, signifi cant differencess were rather rare. Particularly the gluten-index and the sedimentation value promoted by S fertilization were among the tested parameters. Therefore, S-fertilization in improving bread-making quality of wheat in the region should not be disregarded. Grain yield and quality could be promoted simultaneously with increasing N-doses.
Sowing date is an important factor to change of maize (Zea mays L.) yield in temperate zone. Dela... more Sowing date is an important factor to change of maize (Zea mays L.) yield in temperate zone. Delay to sowing change to temperature for during the growth period. Crop could be damage for high temperature in some critical period (seedling, grain filling). The objective of this study is determination of sowing date effect on yield, dry matter accumulation, leaf area index and some growth parameters in maize crops. Two experiments were conducted in the experiment from 2005 to 2006 with two maize hybrids (31G98 32K61). The treatments consisted of different sowing dates. Cob yield, dry matter accumulations, leaf area index (LAI), net assimilation rate (NAR) and crop growth rate (CGR) was measured. The result of the study there was no significant differences among of the varieties in cob yield. The first year the maximum dry matter yield was obtained 31G98 to the first sowing date. Optimum LAI values showed the same variety in the same production period. The second sowing date in the first year of the highest dry matter yield varieties gave 32K61. NAR and CGR curves obtained gave similar values. The first product resulting from the NAR and CGR curves has more stable than the second product.
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