الفهرس 
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Abstract
Two field experiments were carried out at the Experimental Farm, Faculty of Agriculture, Menoufia University, Shebin El-Kom, Egypt during 2015/2016 and 2016/2017 seasons. Such experiments aim to study the effect of mineral and organic fertilization systems on morphophysiological characters, dehydrogenase activity, leaf nutrients content, yield and technological and rheological properties of some bread wheat (Triticum aestivum L.) varieties. Each experiment included 35 treatments, which were the combination of seven fertilization systems and five wheat varieties. The tested experimental treatments are as follow:
A- Mineral and organic fertilization systems:
1- without fertilization “control”
2- 100% mineral N/fed “ 75 kg N”
3- 100% organic N/fed “ 6 ton compost”
4- 50% mineral N + 50% organic N/fed “37.5 kg N + 3 ton compost”
5- 50% organic N + 100% natural phosphate ore /fed “3 ton compost + 74 kg phosphate ore”
6- 50% organic N + 100% natural potassium ore /fed “3 ton compost + 238 kg potassium ore”
7- 50% organic N + 100% natural phosphate ore + 100% natural potassium ore /fed “3 ton compost + 74 kg phosphate ore + 238 kg potassium ore”
B- Varieties:
1- Gemmeiza 11
2- Gemmeiza 12
3- Misr 1
4- Giza 171
5- Sids 13
The treatments were arranged in a split plot design with three replications, where the fertilization systems were randomly distributed in the main plots, while wheat varieties were occupied in the sub plots.
The recommended fertilizers rate (100%) for wheat growth under experiment conditions was 75 Kg N, 15.5 kg P2O5 and 24 K2O/fed for nitrogenous, phosphatic and potash fertilizers, respectively. Nitrogen was added in the form of ammonium nitrate (33.5 % N). However, phosphorus and potassium were added in the form phosphate ore (21.0 P2O5) and potassium ore (10.10 K2O), respectively. Soil application of synthetic mineral nitrogen fertilizer was divided into three doses; one dose (20%) applied before the sowing irrigation, while the remain amount (80%) was equally splitted and applied before the first and second irrigations. Organic fertilizers (compost) and nature ores (phosphate ore and potassium ore) were applied in one dose during soil preparation.
Measurements
A- Morphophysiological characters:
1- Heading date (days) 2- Plant height (cm)
3- Flag leaf area (cm2) 4- Total chlorophyll
B- Dehydrogenase activity (μg TPF/ g dry soil /24 hours)
The Dehydrogenase activity (DHA) in soil rhizosphere was determined at 110 DAS according to Thalmann (1967).
C- Leaf nutrients content:
NPK contents (mg/g leaves dry weight) were determined in dried leaves at 110 DAS.
D- Yield and its components:
1- Number of spikes/ m2. 2- Spike length (cm).
3- Number of grains/spike. 4- 1000-grain weight (g.).
5- Spike weight (g.). 6- Grain yield (ton/fed).
7- Straw yield (ton/fed). 8- Biological yield (ton/fed).
9- Harvest index (%).
E- Technological and rheological properties:
E.1. Preparation of wheat for milling:
Wheat grains were manually cleaned, tempered to reach 14% moisture content, then milled using Quadrumat Junior flour mill to obtain flour, coarse bran and fine bran% .
E.2. Chemical analysis:
Moisture, protein, fats, ash and crude fiber contents were determined in whole grains according to A.O.A.C. (2005). Carbohydrates were calculated by difference methods. Wet and dry gluten of wheat flour dough were determined according to the method of A.A.C.C. (2000).
E.3. Flour colour determinations
Objective evaluation of color of wheat flour was estimated. Hunter a*, b* and L* parameters were measured with a color difference meter using a spectro- colourimeter.
E.4. Rheological properties of dough
Rheological properties of the different produced flour doughs were carried out with farinograph and extensograph tests according to the methods described in A.A.C.C. (2000).
E.4.1. Farinograph test:
The flour samples were tested by brabender farinograph to determine the following parameters:
1- Water absorption % 2- Arrival time (min)
3- Dough development time (min) 4- Dough stability
5- Mixing tolerance index 6- Degree of weakening.
E.4.2. Extensograph test:
The flour samples were tested by brabender extensograph to determine the following parameters:
1- Resistance to extension (BU) 2- Extensibility (mm)
3- Proportional number 4- Dough energy (cm2)
The obtained results could be summarized as follows:
A- Morphophysiological characters:
1- Data showed that fertilization systems significantly affected morphophysiological characters. Application of 100% mineral nitrogen (75 kg N/fed) causes increase in heading date and plant height. However, application of 50% mineral N + 50% organic N/fed followed by 100% mineral nitrogen/fed produced the highest significant values of flag leaf area and chlorophyll content compared to other treatments.
2- There are significant differences among the tested varieties for morphophysiological characters. Misr 1 and Giza 171 varieties exhibited the highest days from sowing to 50 % heading. However, Gemmeiza 11 and Giza 171 varieties have the highest values of plant height, flag leaf area and chlorophyll content compared to the other varieties.
3- Data of the interaction between the fertilization systems and wheat varieties indicated that the highest number of days from sowing to 50% heading were obtained when Misr 1 fertilized with 100% mineral N/fed. The tallest plants were obtained by fertilized Gemmeiza 11 with 100% mineral N/fed. However, Giza 171 and Gemmeiza 11 plants which were fertilized with 50% mineral N + 50% organic N/fed produced the greatest flag leaf area and chlorophyll content.
B- Dehydrogenase activity:
1- Fertilization systems significantly increased dehydrogenase activity compared to unfertilized plants. The greatest values were obtained by adding 100% organic N/fed followed by 50% mineral N + 50% organic N/fed but with significant differences between them.
2- Giza 171 variety exhibited a remarkable increase in dehydrogenase activity more than other varieties. Meanwhile, the lowest dehydrogenase activity was obtained by Misr 1 variety.
3- Adding 100% organic N/fed to Giza 171 variety produced the highest significant values of dehydrogenase enzyme activity. However, unfertilized Misr 1 plants produced the lowest one.
C- Leaf nutrients content
1- Fertilized plants with any mineral and/or organic fertilizers gave higher significant contents of NPK in favor of 50% mineral N + 50% organic N/fed for N content. However, higher P and K contents in leaves were achieved by adding 50% organic N + phosphate ore + potassium ore/fed more than plants which didn’t receive fertilizers.
2- The highest significant values of N, P and K contents were obtained by Giza 171 and Gemmeiza 11 varieties without significant differences between them in both seasons. However, Gemmeiza 12 variety had the lowest significant values of such elements.
3- Giza 171 and Gemmeiza 11 varieties surpassed the other varieties and exposed their higher mean values of N content in leaves when fertilized with 50% mineral N + 50% organic N/fed, and with adding 50% organic N + phosphate ore + potassium ore/fed for K content.
D- Yield and its components
1- Yield and its components were significantly and positively responded to application of all fertilization systems compared to unfertilized plants. The highest increases were obtained generally by application of 50% mineral N + 50% organic N/fed compared to other fertilization systems in both growing seasons.
2- Yield and its components were statistically significant differed by the five tested wheat varieties. The highest values were obtained by Giza 171 followed by Gemmeiza 11 for most characters during both seasons. Meanwhile, Misr 1 recorded the lowest ones except straw yield in the first season.
3- The interaction between fertilization systems and varieties were found to be significant for yield and its components except spike length and harvest index in both seasons. In general, fertilized Giza 171 or Gemmeiza 11 with 50% mineral N + 50% organic N/fed seemed to be most effective combination for increasing yield and its components.
E- Technological and rheological properties
E.1- Milling properties
1- Insignificant differences were detected among fertilization system for flour, fine bran and coarse bran percentages.
2- The tested wheat varieties were not significantly differed in the milling characters studied.
3- The interaction between fertilization systems and varieties were not significant for milling characters.
E.2- Chemical analysis
1- Significant differences were detected among fertilization system for chemical composition except moisture and fates %. Application of
50% mineral N + 50% organic N/fed exhibited the highest values of protein and fibers % as well as wet and dry gluten%. However, the higher carbohydrates and ash % were recorded by plants which fertilized with 50% organic N + phosphate ore + potassium ore/fed.
2- Varieties were significantly differed in their chemical composition. Giza 171 and Gemmeiza 11 recorded higher significant protein, wet gluten and dry gluten%. The highest values of carbohydrates was recorded by Gemmeiza 12, while ash was achieved by Sids 13.
3- Fertilized Gemmeiza 11 or Giza 171 plants with 50% mineral N + 50% organic N/fed had the maximum values of protein, wet gluten and dry gluten%. However, higher carbohydrates % were obtained from fertilized Gemmeiza 12 plants with 50% organic N + phosphate ore + potassium ore/fed.
E.3- Flour colour parameters
1- Significant differences were detected among fertilization system for flour colour parameters. Application of 50% mineral N + 50% organic N/fed followed by 100% organic N/fed exhibited the highest values of whiteness (L) and lowest redness (a) and yellowness (b).
2- Giza 171 and Gemmeiza 11 recorded the highest significant values of whiteness (L) and lowest redness (a) and yellowness (b) compared to other varieties.
3- The interaction between fertilization systems and varieties indicate that Giza 171 variety grown under 50% mineral N + 50% organic N/fed produced the highest lightness flour. Moreover, the lowest redness colour values were obtained from plants of Gemmeiza 11 or Giza 171 fertilized with 50% mineral N + 50% organic N/fed. However, the lowest yellowness flour were obtained by Gemmeiza 11 especially when treated with 100% organic N/fed.
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Summary
E.4. Rheological properties of dough
E.4.1. Farinograph properties
1- Farinograph properties of dough were differed among fertilization system. Flour of fertilized plants with 50% mineral N + 50% organic N/fed recorded highest values of water absorption and dough stability. However, the highest values of dough development time and dough weakening were achieved by fertilized with 100% organic N/fed, while highest mixing tolerance index value was obtained by unfertilized plants.
2- Data showed that Giza 171 dough recorded the highest values of water absorption and dough stability, Gemmeiza 11 recorded more dough development time. However, higher mixing tolerance index and dough weakening values were obtained by Misr 1 dough.
3- The interaction data indicated that the greatest water absorption percentage and dough stability were obtained by fertilized plants of Giza 171 variety with 50% mineral N + 50% organic N/fed. However, the highest mixing tolerance index was happened when the plants of Gemmeiza 12 and Misr 1 were unfertilized with any fertilizers. On the other side, the highest values of dough weakening were obtained by fertilized Misr 1 with 50% mineral N + 50% organic N/fed followed by unfertilized plants of Gemmeiza 12 variety.
E.4.2. Extensograph properties
1- Wheat flour dough of plants fertilized with 100% mineral N/fed followed by 50% organic N + phosphate ore + potassium ore/fed showed higher resistance to extension. However, the highest value of extensibility of dough was obtained when fertilized plants with 50% organic N + potassium ore/fed and 50% organic N + phosphate ore/fed. Concerning dough energy (cm2), flour dough of 50% organic
N + potassium ore/fed and 50% mineral N + 50% organic N/fed registered the highest dough energy.
2- Data showed that Giza 171 followed by Sids 13 recorded the highest values of resistance to extension, while Misr 1 recorded the highest values of extensibility. Concerning the dough energy, Sids 13 dough followed by Giza 171 dough recorded the highest values.
3- The interaction data showed that tested varieties differed responses to various fertilization. Adding 50% mineral N + 50% organic N/fed to Giza 171 plants was the effective treatment for increasing resistance to extension. However, the highest value of extensibility was achieved by Gemmeiza 11 when fertilized with 50% organic N + phosphate ore/fed. On the other hand, Sids 13 plants which were fertilized by 50% organic N + potassium ore/fed and 50% organic N + phosphate ore + potassium ore/fed produced the greatest dough energy.