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Estimation of the baking quality of wheat flours based on rheological parameters of the mixolab curve
2011
Iuliana Banu | Georgeta Stoenescu | Violeta Ionescu | Iuliana Aprodu
The Mixolab device in view of the characterisation of the thermo-mechanical behaviour of ten different flours, and establishing the correlations between the rheological parameters of wheat flour supplemented with different additives such as fungal α-amylase, fungal hemicellulase, and fungal xylanase weres exploted. The rheological measurements were performed using the Mixolab, Alveograph, and Rheofermentometer. Our results indicated significant positive and negative correlations between the parameters investigated. The changes of the Mixolab curve trend depended on the amylase doses. Significant correlations were established also between the Mixolab parameters and the results of the baking tests; the β slope, C2, C3, and C4 were positively correlated with the specific volume of the bread. Taking into account the results obtained, we may conclude that Mixolab is a complex device that renders the evolution of the bread during the entire technological process, from the dough making to the starch retrogradation.
Show more [+] Less [-]Study of silicon effects on antioxidant enzyme activities and osmotic adjustment of wheat under drought stress
2011
Sara Tale Ahmad | Raheem Haddad
The effect of silicon (Si) was investigated on the major antioxidant enzyme activities including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD), relative water content (RWC), chlorophyll and soluble protein contents, proline (Pro) and glycine betaine (GB) accumulation in three different growth stages (2nd, 4th leaf and tillering stages) of wheat (Triticum aestivum L.) plants under drought stress. The experiment was performed in a completely randomized design for three treatments including control, drought and Si-drought (2mM silicate sodium/kg) with three replications in a greenhouse. The results indicated that Si partially offset the negative impacts of drought stress increasing the tolerance of wheat by rising Pro and GB accumulation and soluble protein content. Compared with the plants treated with drought, applied Si significantly enhanced the activities of SOD, CAT, APX and POD. In contrast, drought stress caused a considerable decrease in RWC, chlorophyll and soluble protein contents. This Si effect was time-dependent and became stronger in the tillering stage. The results of the present experiment coincided with the conclusion that Si alleviates water deficit of wheat by preventing the oxidative membrane damage and may be associated with plant osmotic adjustment.
Show more [+] Less [-]Effect of controlled sprinkler chemigation on wheat crop in a sandy soil
2011
Mahmoud Atef Sayed | M. A. Naguib Bedaiwy
A two-year experiment was conducted in the desert west of the Nile Delta to study the effect of applying fertilizers and other agronomic chemicals through sprinkler irrigation water (a technique referred to as chemigation) on wheat grain yield. Experiment included three levels of irrigation inputs, namely: I1 = potential evapotranspiration rate (ETp), I2 = 0.8 ETp and I3 = 0.6 ETp, and included two application method of fertilizers and herbicide (chemication and traditional). Applying chemigation resulted in significant increase in grain yield, ranging between 9.9% and 50.0% with averages of 43.2% and 14.5% over the first and second seasons, respectively. Irrigation treatment I1 produced higher grain yield than the other two irrigation treatments both under traditional and chemigation methods as a result of better fertilizer distribution in the root zone. Grain yield associated with combined I1 and chemigation was highest of all treatments and was greater than Egypt's national average by 14% and 9% for seasons 1 and 2, respectively. Chemigation resulted in more uniform distribution of nitrate-nitrogen throughout the root zone with nitrate levels falling within safe limits. Concentrations under traditional application resulted in lower levels in upper soil and greater levels at deeper soil of the root zone exceeding safe limits and subjecting the soil and groundwater to contamination hazards. For both N and K fertilizers, fertilizer use efficiency was greater under chemigation than under traditional application. Efficiencies increased with increasing irrigation water, apparently due to better fertilizer distribution. Applying herbicides with sprinkler irrigation water reduced weed infestation from 48% to 6.5%. As a result of improved yield under chemigation, an increase in revenue per hectare of 112.6% was achieved.
Show more [+] Less [-]Effect of Droplet Size on Weed Control in Wheat
2011
Esehaghbeygi, Ali | Tadayyon, Ali | Besharati, Shahin
The efficacy of different water volume and nozzle systems, comprising spinning-discs with two disc speeds (low volume, LV), a spinning-cage rotary atomizer (median volume, MV), a flat fan nozzle Teejet-11004 (high volume, HV), and no weed control, were assessed for the application of 2,4-D to control weeds in irrigated wheat. The herbicide was applied at the tillering stage of cultivated wheat, Ghods variety. Sprayer nozzle performance was evaluated in terms of wheat grain yield, weed shoot biomass, and wheat residual (straw), at the research farm of Shahrekord University in 2007 and 2008. ANOVA analysis indicated that nozzle type, and the year had significant effects on grain yield and dry biomass of weeds at 5% confidence. There was a significant difference between the two years of the experiment for all variants. The results indicated that the median diameter volume using the spinning disc (low disc speed) for herbicide application, gave better weed control than others. The spinning disc nozzle decreased water use and so it was cheaper to operate. It did not, however, significantly improve herbicide efficacy, especially in dense canopies compared with the conventional flat fan nozzles. The spinning-disc had more droplet uniformity at high disc speeds compared with the cage rotary atomizer, but was more effective for weed control at low disc speeds.
Show more [+] Less [-]Effects of row spacing on soil water and water consumption of winter wheat under irrigated and rainfed conditions
2011
X.B. Zhou | Y.H. Chen | Z. Ouyang
The results of two seasons' work on soil water content (SWC), evapotranspiration (ET), total dry matter (TDM), and harvest index (HI) of crops under different row spacing (RS), as well as possible ways to improve water utilization, have been reported. Field experiments were carried out at the Experimental Farm of Shandong Agricultural University (36°09'N, 117°09'E) in 2006-2007 and 2007-2008. Four types of RS were treated under two different water conditions (rainfed and irrigated) and set up in a randomized plot design. RS did not exhibit any obvious effects on SWC during the study period. SWC was enhanced evidently by irrigation, especially in the 10-60 cm soil layer. Irrigation increased the ET of crop. At the seeding-jointing stage, the ET of RS14 was significantly higher than those during other treatments (P < 0.05). Irrigation increased yields, ET, and TDM, while it decreased water use efficiency and HI. There were significantly negative correlations between TDM and RS (P < 0.05). The HI of the rainfed crop was higher than that of the irrigated crop. Results showed that high yields of wheat could be achieved in northern China by reducing RS under uniform planting density conditions.
Show more [+] Less [-]Effect of poultry litter and livestock manure on soil physical and biological indicators in a rice-wheat rotation system
2011
J.T. Li | X.L. Zhong | F. Wang | Q.G. Zhao
Organic manure is considered as a beneficial fertilizer on soil quality and an excellent alternative resource of chemical fertilizer (CF). However, organic manure from intensive farms may have a negative impact on soil quality because of containing some harmful components, such as heavy metal and antibiotics. The aim of this study was to determine the influence of poultry litter (PL) and livestock manure (LM) from intensive farming on soil physical and biological indicators of soil quality. Results showed that PL and LM amendment increased soil macropore and mesopore volumes and decreased soil micropore volumes. Tensile strength in PL and LM treatment were lower than those in CF, while soil aggregate wet stability index were greater than those in CF. Compared with CF treatment, the microbial biomass C and N contents (+89%, +74%), soil basal respiration rate (+49%) and soil microbial quotient (+45%) in PL and LM treatment were significantly greater. Significant linear correlations were found between soil organic carbon and most soil physical and biological properties (P < 0.01). The results suggested that modern intensive farm manures can be alternate chemical fertilizers as a main fertilizer to improve soil physical and biological indicators in a rice-wheat system.
Show more [+] Less [-]Evaluation of Promising durum Wheat lines under on farm condition in Golestan Province.
2011
Ja`far Bay, Jabbar Alt | Kalateh A`rabi, Mahdi | Fallahi, Hossein A`li | Suqi, Habib Ol-Lah | Haji A`razi, Emam Berdi | Dehqan, Mohammad A`li | Hamzeh, Ruh Ol-Lah | Davallu, I`sa | Qardashli, Naz Berdi | Qoli Pur, Ahmad | Gorgani, Yusef
In order to transfer new technology and research findings to the farmers, fields and to evaluate advanced and promising lines of durum wheat under on farm condition, four lines including the checks (Aria)and(Dna) as well as bread wheat (Milan/sha7) were evaluated in three regions of the Golestan province in 2008-2009. The experiment was laid out in an R.C.B.D with three replications and seven treatments, the plot size was 25 m-2, and seed rate was 450 per square meter. Rows were 20 centimeters apart. Lines studied in previous experiments at agricultural research station of Gonbad and in other temperate regions of the country, out yielded the checks. The study was carried out to compare their yield and other traits with check under on-farm condition. Note taking of the important characters were done during the season, simple and combined analysis of variance were performed. Result of yield trial of promising durum wheat lines in Gonbad (Haji Ghoshan) showed significant differences among lines. Lines 2 and 1 (KUCUK (DM-82-2) and SKEST //HUI/TUB/3/SILVER (DM-82-4), respectively) produced higher yield (3438 and 3883) than that of the check (Aria). There were significant differences among lines in Kalaleh at 0.01 probability level. Treatments 4 and 1 produced 4804 and 4029 Kg/ha out yielding check at 0.01 probability level. Treatments 3, a bread wheat, produced 6054 Kg/ha grain yield whereas treatments 1 and 4(DM-82-2) KUCUK respectively, had 4380 Kg/ha grain yield. The check produced 5471 Kg/ha. The combined analyzes of variance of promising lines of durum wheat in the three locations showed that the effect of location on yield was significant. The higher yield in Agh Ghala might be attributed to favorable environmental condition and to lesser head fusarium. The significant genotype x location interaction showed that genotypes responded differently to environments. The highest grain yield was obtained by treatment (Milan/sha7) with 5484 and treatment 1 KUCUK (DM-82-2) and E 90040/ MFOWL_13//LOTALL_6 (DM_85/5) ranked next producing 4380 and 4283 kg/ha, respectively.The check (Aria) produced 3823 kg/ha .Based on suitable agronomical traits and in order to avoid biotic and a biotic stresses, genetic variability is of great importance, such that if this condition occurs, farmers, crop will not fail. There fore genotypes KUCUK (DM_82_2) and (E90040/MFOWL_13//LOTAIL_6 (DM_85_5)) as well as Aria might be recommended for the target regions as a sustain abler crop production system.
Show more [+] Less [-]The homoeologous regions on long arms of group 3 chromosomes in wheat and barley harbour major crown rot resistance loci
2011
C.J. Liu | J. Ma | H.B. Li | Y.X. Liu | G.R. Liu | S.M. Wen | M.X. Zhou | G.J. Yan | S. Chakraborty
Crown rot (CR), caused by various Fusarium species, has become an important cereal disease worldwide and growing resistant varieties is an essential strategy to reduce the $A80 mil annual loss from CR in Australia. To facilitate the breeding of resistant varieties, we have screened 2514 wheat and 1059 barley genotypes and identified several lines with high levels of CR resistance in each crop. Initially focused on two wheat and one barley resistance sources, we have identified major QTL with unprecedented magnitudes. Two wheat QTL explain between 35% (LOD 7.6) and 49% (LOD 10.8) and the barley QTL explains up to 63% (LOD 14.8) of the phenotypic variance. One of the wheat QTL has been further assessed in four validation populations, and the presence of this QTL alone reduces CR severity by 33% on average. Surprisingly, all of the three major CR QTL are located in similar regions on the long arms of the homoeologous group 3 chromosomes, the two wheat QTL on 3BL and the barley QTL on 3HL. The possible homoeologous relationship between the 3BL wheat QTL and the 3HL barley QTL warrants further investigation. Relative rearrangements between 3H and 3B chromosomes are unknown, although the relative distances between the different QTL and the centromeres seem to be different. Compared with the barley QTL, the 3BL wheat QTL seems to be more distally located. However genetic distance can be affected by many factors including the use of different populations, thus the differences in genetic distances between the two different genera may have only limited value. The physical map of wheat chromosome 3B, which was recently made available as the first such resources for wheat, would make such a study much easier. Results will be presented on the detection, genetic analysis and mapping of these new sources of CR resistance.
Show more [+] Less [-]Evaluation of improved durum wheat genotypes in on-farm trials.
2011
Mohammadi, Mohtasham | Jaberiyan, Mohammad Ali | Parhiz, Jalal | Karimi Zadeh, Rahmat Ol-Lah | Sadeq Pur, Vali | Arvaneh, Faz Ol-Lah
To accelerate in transformation of research results, six improved durum wheat lines, were evaluated in Dehdasht and Likak regions in 2009. They were planted in randomized complete block design (RCBD) with 4 replications, through 300 kernel per square meter density and 25 centimeter row spacing. During vegetative and reproductive stages, different characters were recorded. The most important traits were: days to heading, plant height, thousand kernel weight and grain yield. Based on simple and combined analysis of variance on grain yield, there was no significant difference between lines and locations. Although, occurrence of sever heat and drought stresses during growth period, considered lines showed relatively good performance. However, Due to existence of Dehdasht cultivar which is released recently, increasing of grain yield and strength of agronomic traits for candidate lines is necessary.
Show more [+] Less [-]Effects of wheat sourdough process on the quality of mixed oat-wheat bread
2011
Flander, L. | Suortti, T. | Katina, K. | Poutanen, K.
The aim of this work was to study the effects of sourdough fermentation of wheat flour with Lactobacillus plantarum, on the quality attributes of mixed oat-wheat bread (51 g whole grain oat flour and 49 g/100 g white wheat flour). Emphasis was laid both on β-glucan stability as well as bread structure and sensory quality. The variables of the sourdough process were: dough yield (DY), fermentation time, fermentation temperature, and amount of sourdough added to the bread dough. The sourdough process was shown to be a feasible method for mixed oat-wheat bread, and, when optimized, provided bread quality equal to straight dough baking. A small amount (10g/100 g dough) of slack sourdough fermented at high temperature for a long time resulted in the most optimal sourdough bread with the highest specific volume (3.5 cm³/g), the lowest firmness after 3 days storage (0.31 kg), and low sensory sourness with high intensity of the crumb flavour. Wheat sourdough parameters did not affect the content of oat β-glucan in the bread. Additionally, both straight dough and sourdough bread contained 1.4–1.6 g β-glucan/100 g fresh bread. The average molecular weight of β-glucan was 5.5 × 10⁵ in both types of bread, while that of oat flour was 10 × 10⁵. This indicates that a slight degradation of β-glucan occurred during proofing and baking, and it was not affected by variation in the acidity of the bread between pH 4.9–5.8.
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