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Global implications of national price policies on the wheat market - quantitative assessment of world market effects
2009
J. Ziolkowska | K. Jechlitschka | D. Kirschke
Price policy instruments are common political measures to influence the supply and export of agricultural products. Different price policies have thus different influence on national agricultural markets. These policies can also influence the world market and third countries provided that the exporting country places a high share of its production on the world market. Using a Cobb-Douglas market model we quantitatively assess global implications of national price policies in the EU-27, Russia, and the US (as leading wheat exporting countries) on the world market price for wheat and on welfare, foreign exchange, and producer surplus in third countries. The results prove that increasing protectionist price policies in the EU-27, Russia, and the US would only slightly influence the welfare in third countries. This policy would however bring about a higher decrease of foreign exchange and producer surplus in third countries.
Show more [+] Less [-]Effects of conservation tillage on soil porosity in maize-wheat cropping system
2009
N. Tangyuan | H. Bin | J. Nianyuan | T. Shenzhong | L. Zengjia
A study was conducted on the effect of two single practices, including soil tillage and returning straw to soil, and their interaction on soil porosity of maize-wheat cropping system. Field experiments involved four tillage practices, including conventional tillage (C), zero-tillage (Z), harrow-tillage (H) and subsoil-tillage (S), with straw absent (A) or straw present (P). Total porosity, capillary porosity and non-capillary porosity of soil were investigated. The results showed that the soil total porosity of 0-10 soil layer was mostly affected; conventional tillage can increase the capillary porosity of soil, but the non-capillary porosity of S was the highest. Returning of straw can increase the porosity of soil. Through the analysis of affecting force, it can be concluded that interaction of soil tillage and straw is the most important factor to soil porosity, while the controlling factor to non-capillary porosity was soil tillage treatment.
Show more [+] Less [-]Effects of putrescine and low temperature on the apoplastic antioxidant enzymes in the leaves of two wheat cultivars
2009
T. Çakmak | Ö. Atici
The effects of putrescine (a polyamine), low temperature and their combinations on the activities of apoplastic antioxidant enzymes were studied in the leaves of two wheat cultivars, winter (Dogu-88) and spring (Gerek-79). Fifteen-day-old wheat seedlings were treated with putrescine solutions (0.1, 1 and 10mM) prior to cold treatment (5/3°C). The activities of apoplastic catalase, peroxidase and superoxide dismutase were determined in the leaves both under normal and cold conditions at 1, 3 and 5 days. The results indicate that cold treatment significantly increased the activities of apoplastic catalase, peroxidase and superoxide dismutase in winter wheat while not generally affecting spring wheat. Under control conditions, the putrescine treatments were more effective in increasing the enzyme activities in winter wheat than in spring wheat. However, under cold conditions, the putrescine treatments surprisingly induced enzyme activities in spring wheat while generally reducing those in winter wheat leaves. The results show that putrescine may act as an agent inducing primary changes in the apoplastic antioxidant system of wheat leaves during reactive oxygen species-mediated damage caused by low temperature stress.
Show more [+] Less [-]Effects of increased ammonia on root/shoot ratio, grain yield and nitrogen use efficiency of two wheat varieties with various N supply
2009
Li Jing | Li Shi-Qing | Liu Yi | Chen Xiao-Li
The effects of elevated atmospheric NH3 on growth and yield parameters of two winter wheat varieties, the high water and fertilizer-demanding variety Xiaoyan 6 (XY6) and the drought-resistant variety Changhan 58 (CH58), grown with two levels of N fertilization, were studied in Open-Top Chambers. The results showed that in combination with the high N treatment increasing the atmospheric NH3 concentration to 1000 nl/l from the ambient level of 10 nl/l NH3 significantly (P < 0.05) reduced the biomass and the root/shoot ratios of the plants, especially in XY6 plants, mainly because it negatively influenced root biomass production at anthesis and mature stages. In addition, the grain yield of XY6 was by 1.51% higher, while that of CH58 was 13.2% lower, following exposure to the elevated atmospheric NH3 concentration rather than the ambient concentration in combination with the high N treatment. In contrast, in combination with the low N treatment, elevated atmospheric NH3 had significantly and non-significantly positive effects on the grain yield of XY6 and CH58 plants, respectively. The Nitrogen Use Efficiency (NUE) and related parameters were all lower in plants of both varieties exposed to the high atmospheric NH3 concentration together with either the high or low N treatment.
Show more [+] Less [-]Effects of nitrogen nutrition, fungicide treatment and wheat genotype on free asparagine and reducing sugars content as precursors of acrylamide formation in bread
2009
P. Martinek | K. Klem | M. Váňová | V. Bartáčková | L. Večerková | P. Bucher | J. Hajšlová
Acrylamide, a monomer with neurotoxic and potential carcinogenic effect, is formed via the Maillard reaction in heat-treated carbohydrate-rich foods. The major acrylamide precursors are reducing sugars and the amino acid asparagine. The aim of this study was to analyse effects of nitrogen nutrition, leaf disease control, wheat genotype and their interactions on acrylamide precursors content in wheat flour. Asparagine content was generally increasing at higher nitrogen doses, and nitrogen dose increase from 0 to 180 kg/ha increased the asparagine content to about 250%. The highest asparagine levels were determined at early spring nitrogen application. In the year 2006 with high leaf disease infestation, fungicide treatment decreased asparagine content particularly at higher nitrogen doses. In 2007, the effect of leaf disease control did not express in respect of very low infestation level. Close relationship between protein content and free asparagine in wheat flour was determined when leaf disease stress (fungicide treatment) and drought stress (year) were constant. Asparagine content was strongly influenced by wheat genotype and the differences between genotypes exceeded 200%. Effect of higher intensity was lower as compared to nitrogen nutrition, with regard to compensatory effect of fungicide treatments. Glucose content in wheat flour decreased both with fungicide treatment and total intensity level. Nitrogen dose increased glucose content up to 120 kg N/ha. Higher nitrogen doses decreased glucose content to initial level.
Show more [+] Less [-]Rheological properties of dough made from grain amaranth-cereal composite flours based on wheat and spelt
2009
Silva Grobelnik Mlakar | Martina Bavec | Matjaž Turinek | Franc Bavec
The purpose of this study was to investigate the effect of the addition of amaranth wholegrain flour on the rheological characteristics of wheat and spelt flour dough. Organically produced composite flours made from basic flours of wheat (refined) or spelt (refined, wholegrain) and amaranth flour in the propostions of 10%, 20%, and 30% (flour basis) were compared to cereal flours. Dough was analysed for its amylographic, farinographic and extensographic properties. The amaranth substitution altering of the examined measures relates to a certain extent to the properties of the basic flour used. By increasing the amaranth replacement ratio, the gelatinisation temperature, water absorption, development time, and stability increased whereas the dough softening was only slight. The amaranth addition strengthened the dough, mainly by decreasing its extensibility and, in spelt containing composite flours, also by increasing the resistance to extension. Considering the results obtained and the characteristics of the basic flour used, the amaranth substitution of 10-20% evidently improves some rheological properties and strengthens the dough. The present study provides the first report on the spelt-amaranth blends and dough extensograph behaviour of amaranth composite flours
Show more [+] Less [-]Influence of uniconazole and plant density on nitrogen content and grain quality in winter wheat in South China
2009
H. Han | W. Yang
Superior protein quality and consistent processing quality is needed for winter wheat marketing in South China. It has been shown that uniconazole concentration and plant density are certainly related to crop growth. An experiment was conducted to investigate the effects of uniconazole concentration and plant density on nitrogen content and grain quality in winter wheat (Triticum aestivum L.). Trials were managed to provide three levels of density (90 × 104, 180 × 104, and 270 × 104 per ha) over plots receiving four levels of uniconazole concentrations (0, 10, 20, and 40 mg/kg) which were applied to seeds before sowing. The results revealed that the contents of N accumulated in ear, stem, and leaf were higher in uniconazole concentrations than that in control, and the effect of uniconazole on main stem was bigger than that on tillers. The grain protein was significantly (LSD, P < 0.05) higher in uniconazole concentrations than that in control. Uniconazole at 20 mg/kg was the most favorable for improving grain protein and protein fractions. Application of uniconazole concentrations also significantly (LSD, P < 0.05) increased WGC (wet gluten content) and SDS (sedimentation volumes), prolonged DDT (dough development time) and DST (dough stable time), and improved WA (water absorption), increased VV (valorimeter value), and subsequently improved the processing quality of wheat grains. These results suggest that a combination of uniconazole concentration and plant density should be applied in South China.
Show more [+] Less [-]Yield Comparison of moderate durum wheat promising lines with checks(pishtaz & Aria) in Neishabur and khalil abad (On-farm)
2009
Taheriyan, Majid | Kabiriyan, Hamid Reza | Shurabi, A`li Asghar | Shad Mehri, Ahmad | E`marlu, Mohammad
In order to comparison yield of four durum wheat promising lines with checks (Pishtaz and Aria), this experiment was conducted in RCBD with six lines /cultivars and three replicated in two locations during 2007-08 crop season. This experiment was planted in farmers , field at Foshanjan (NE of Neishabour) and Khalil-Abad (South of Neishabour). Agronomical practices such as preparing of seedbed, use of fertilizers and so on were done on conventional practices of the region. Result showed that D-79-18 with 3508 kg/ha grain yield have better performance than other lines and checks, so can introduce as better and new promising line.
Show more [+] Less [-]Evaluation of advanced bread wheat lines under rainfed conditions on Farmers field.
2009
Qobadi Bigvand, Jamshid | Mohammadi, Mohmmad | Daraei, Ebrahim | Naseri, Mahmud | A`bbasi, A`li | Tanhaei, Mansur | Rostami, Safdar | Karimi, Behruz
This experiments were conducted in 4 regions of Kermanshah (Islam Abad, Bilvar, Kangavar and Songhor) to compare 3 promising bread wheat lines Sabalan and Azar-2 with check cultivar Sardari on farmers fields. The experimental design was RCBD whit 4 replications. Grain yield of Azar-2 and line No. 3 were respectively 8 to 43 percent higher than Sardari in Kangavar and Eslam abad. Lines No. 1 and 2 had 1 and 12 percent grain yield more than Sardari in Bilavar and Eslam abad.
Show more [+] Less [-]Yield comparison of advanced breed wheat promising lines under farmers conditions(on farm) in Kerman.
2009
Mahmudi, Khalil | Kamal Al-Dini, Mohsen | Ravari, Zabih Ol-Lah | Gholam Rezaei, Gholam Hossein A`li | Najafiyan, Gudarz
This project was conducted to find the cultivars with high yield that are adaptable to the region, in farmer's condition in Mahan-Kerman. In this experiment 7 promising lines,M-84-3, M-84-4, M-84-12, M-84-13, M-84-14, M-84-17, M-84-18, selected from the uniform national experiments for moderate climate and Pishtaz cultivar as check were studied using randomized complete blocks with 4 replicates. The ANOVA results show significant (á=0,01) difference in yield of cultivars. Upon mean comparison, lines M-84-18 and M-84-17 with 7050 and 6275 respectively produced more yield than check with 5600 kg/ha (á=0,01). No disease or especial pest infection or lodging was observed in treatments. Therefore, lines M-84-17 and M-84-18 are recommendable for the region, due to their high yield.
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