الفهرس 
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Abstract
In Egypt, there is an extreme shortage in wheat production. Increasing wheat production is therefore, an essential target, and the problem has to be faced on a scientific basic.
Wheat is one of the most important cereal crops of Egypt. It provides 37% of the total calories for the people and 40% of the protein in the Egyptian diet. The local production of wheat covers about 64% of the local consumption. In this context, exploitation of desert lands such as El Wadi El Gedeed is considered as a good hope for agricultural expansion.
The region of El Wadi El Gedeed represents about 45% of the total area of Egypt however; the cultivated area isn’t exceeding 3%. The aim of this work was to improve the biochemical criteria of sensitive cultivars helping withstanding to heat stress that was an important factor limiting growth in this region through using Sids1 (tolerant), Gemmeiza7 (sensitive) and foliar treatment of CaCl2, Eth, SA, MOH, PA and Met. Our results indicated that:
1. Growth traits.
The highest mean values of plant height and RWC were achieved by 0.4% CaCl2. The superior values of fresh and dry weights were recorded by 0.2% CaCl2. Sids1 exceeded Gemmeiza7 at most growth indices at the two growth stages.
The highest results for fresh and dry weights were given by PA (40ppm) at the two growth stages. Met treatment at (40ppm) enhanced all growth parameters at 2nd growth stage. At 1st growth stage Gemmeiza7 surpassed Sids1 in most growth traits at treatment with PA and Met.
At the two growth stages, 20% MOH recorded the highest mean values of most growth parameters. The dose of Eth (200ppm) gave highest mean values of plant height at both growth stages. Gemmeiza7 exceeded Sids1 in plant height and fresh weight at 1st growth stage by Eth.
SA (100ppm) gave the highest mean values of plant height and RWC. SA at 25ppm gave the highest mean values of fresh and dry weights at 2nd growth stage.
2. Photosynthetic pigments content.
CaCl2 (0.8%) gave the highest records of most indices at both growth stages. Sids1 exceeded Gemmeiza7 in Ch b, a + b and total pigments.
PA (40ppm) gave the highest values of most photosynthetic pigments parameters at the two growth stages.
Concerning 1st growth stage the 40ppm Met gave the maximum values of carotenoids, Ch b and total pigments. However, at 2nd growth stage Met (20ppm) gave the maximum mean values of all photosynthetic parameters.
MOH (10%) gave the maximum mean values of pigments at the two growth stages. Sids1 exceeded Gemmeiza7 in Ch a, Ch b, a + b and total pigments in MOH treatment.
At 1st growth stage, Eth (300ppm) gave the highest mean values of Ch a, Ch b, a + b and total pigments. At 2nd growth stage, Eth (400ppm) recorded the highest mean values of Ch b, a + b and total pigments.
Treatment with SA (100ppm) achieved highest mean values of all photosynthetic indices at the two growth stages. At 1st growth stage, Sids1 exceeded Gemmeiza7 in Ch a, Ch b, a + b, carotenoids and total pigments but at 2nd growth stage, Gemmeiza7 exceeded Sids1 in Ch a, Ch b, a + b and total pigments.
3. Antioxidant enzymes activities.
3.1. Catalase and Peroxidase.
CaCl2 (0.4%) enhanced POD and CAT activities at the two growth stages. At 1st growth stage Sids1 surpassed Gemmeiza7 in CAT activity but Gemmeiza7 exceeded Sids1 in POD activity. However, at 2nd growth stage Sids1 surpassed Gemmeiza7 in both enzymes.
At 1st growth stage PA (20ppm) gave the maximum activities of both enzymes. However, at 2nd growth stage the highest activities of both enzymes were achieved by (60ppm) PA while, the highest CAT activity was recorded by 60ppm Met and POD with (40ppm) at 1st growth stage. At 2nd growth stage, Met (20ppm) gave the highest activities of both enzymes. Sids1 surpassed Gemmeiza7 in POD activity by PA and Met treatment.
At 1st growth stage with MOH (10%) gave the maximum CAT activity, 30% gave the highest activity of POD. Sids1 exceeded Gemmeiza7 in both enzymes’ activities. At 2nd growth stage, 10% gave the maximum both enzymes. Sids1 exceeded Gemmeiza7 in POD in MOH treatment.
Eth (300ppm) enhanced POD activity at 1st growth stage. Sids1 surpassed Gemmeiza7 in POD but Gemmeiza7 exceeded Sids1 in CAT activity. At 2nd growth stage, the highest CAT activity was achieved by (200ppm) Eth but POD activity at Eth (400ppm).
SA (100ppm) enhanced both enzymes at the two growth stages. At 1st growth stage Sids1 exceeded Gemmeiza7 in CAT and POD activities.
3.2. Superoxide dismutase isozyme.
Zymogram gel of SOD isozymes pattern revealed the presence of about 5 bands for the two cultivars classified as follows: band no. 5 is present at all treatments of the two tested cultivars and control. Unique bands of (No. 3 and 4) had been observed due to the treatment with Eth at rates (200 and 300ppm) in Sids1, also unique band was observed in Gemmeiza7 after treatment with Eth (400ppm). The treatment of Sids1 with CaCl2, PA and Met increased band intensities hence, the highest values had been detected at CaCl2 (0.2%), PA and Met (20ppm) in bands No. 1, 2 and 5.
4. Lipid peroxidation product (Malondialdehyde).
The minimum mean value was recorded by 0.8% CaCl2 at 1st and 2nd growth stages. Sids1 achieved lower MDA mean value than Gemmeiza7 at the two growth stages.
The lowest mean value was recorded by PA and Met at rate (40ppm) at 1st growth stage, but at 2nd growth stage the lowest value recorded when PA and Met applied at rates (20 and 40ppm) respectively. Sids1 recorded the minimum MDA level than did Gemmeiza7 with PA and Met at 1st and 2nd growth stages respectively.
MOH (30%) gave the lowest level of MDA at 1st and 2nd growth stages. At 2nd growth stage Sids1 had lowest amount of MDA than Gemmeiza7. The lowest MDA content was recorded by (200 and 300ppm) Eth at 1st and 2nd growth stages respectively. Sids1 had lowest amount of MDA than Gemmeiza7 at 1st growth stage.
SA (25ppm) gave the lowest mean value of MDA at 1st growth stage. However, at 2nd growth stage SA at 100ppm took the same trend.
5. Heat shock proteins.
HSPs pattern under different foliar treatment exhibited that, Sids1 gave about 20 bands but Gemmeiza7 demonstrated about 19 bands. The M.wts ranged between (11.34 to 162.47 kDa). Band of M.wt (19.31 kDa) was appeared in Sids1 but disappeared in control and all treatments of Gemmeiza7 (specific for this cultivar). The more intensive bands were present at M.wt (57.30 kDa) for Sids1 and (43.68 kDa) for Gemmeiza7 in control and all foliar treatments. Regarding to Sids1, the more effective doses were 0.2% CaCl2, 40ppm PA, 20ppm Met and 10% MOH as compared with the control where those concentrations gave the highest No. of bands and more intensive bands. However, in Gemmeiza7 the most effective doses were 0.2% CaCl2, 60ppm PA, 40ppm Met, 30% MOH and 100ppm SA.
6. Amino acids content.
6.1. Acyclic amino acids (ACAA).
Application of 0.2% CaCl2 increased the AUAA except valine and ASAA except serine, methionine, lysine and arginine in Sids1. The dose of 0.8% CaCl2 gave the highest rate of ACAA in Sids1. Also, the highest values of ACAA in Gemmeiza7 were recorded at 0.4% CaCl2.
ACAA reached highest rates by application of 60ppm PA for Sids1 and 20ppm for Gemmeiza7. Met (40ppm) gave the maximum values of ASAA except arginine and AUAA in Sids1. Met (20ppm) gave the highest rates of ACAA in Gemmeiza7.
MOH (30%) gave the highest rates of ACAA in both cultivars.
Eth application at concentrations (200 and 400ppm) increased most amino acids (AUAA and ASAA) obtained by Gemmeiza7. The dose of (400ppm) gave the maximum rate of ACAA at Sids1.
SA treatment in Sids1 enhanced AUAA except valine and ASAA except lysine and arginine at SA (25 and 50ppm). In Gemmeiza7, AUAA increased after SA 25 and 100ppm treatment also, ASAA such as (Serine, threonine and lysine) took the same trend.
6.2. Cyclic amino acids (CAA).
The most effective dose in Sids1 was 0.8% CaCl2 gave the highest rates of CAA. However, 0.4% CaCl2 gave the highest records of CAA in Gemmeiza7.
PA (60ppm) gave the highest rate of CAA in Sids1. PA (20ppm) gave the maximum rate of CAA in the Gemmeiza7. The highest level of phenylalanine and proline were at Met 40ppm but the maximum level of tyrosine and histidine recorded at Met (60ppm). In Gemmeiza7 the highest rates of CAA were recorded Met (20ppm).
MOH treatment at (20%) gave the highest values of proline and tyrosine but 30% gave the maximum values of phenylalanine and histidine in Sids1. In Gemmeiza7 the dose of MOH (30%) increased most of CAA.
At Sids1 the most effective dose of Eth that enhanced most of CAA is (400ppm) in both cultivars.
Sids1 when treated with SA (100ppm) exhibited highest values of CAA. Despite, Gemmeiza7 treated with SA (25ppm) gave the highest values of proline and histidine and SA (100ppm) gave highest values of phenylalanine and tyrosine.
7. Minerals content in shoots.
At both growth stages, 0.2% CaCl2 gave the maximum mean values of K+, K/Na ratio except Ca+2 at 2nd growth stage the highest mean value was reported by CaCl2 (0.8%). CaCl2 (0.8%) gave the highest values of Na+ and Fe. Sids1 exceeded Gemmeiza7 in Na+ and Ca+2 but Gemmeiza7 exceeded Sids1 in K/Na ratio and Fe. Mg+2, Na+ and Fe highest mean values were recorded by 0.4% CaCl2. Sids1 exceeded Gemmeiza7 in K+, Na+, K/Na ratio and Mg+2 content at 2nd growth stage.
At 1st growth stage, the highest values of K+, K/Na ratio and Ca+2 were recorded by PA (20ppm). At 2nd growth stage, PA 40ppm recorded the highest mean values of Mg+2 and Fe while PA (20ppm) gave the superior mean values of K+ and K/Na ratio. PA 60ppm gave the highest mean values of Na+ and Ca+2 contents. Sids1 exceeded Gemmeiza7 in Na+ and Ca+2 contents. Gemmeiza7 surpassed Sids1 in K/Na ratio and Fe content.
Applied Met at rate (40ppm) gave the highest mean values of K/Na ratio, Mg+2 and Fe at 1st growth stage whereas, the maximum mean values of K+ and Ca+2 at Met (60ppm). Sids1 exceeded Gemmeiza7 in K+, K/Na, Ca+2 and Fe. At 2nd growth stage, Met at 20ppm recorded highest mean values of K+, K/Na ratio and Ca+2. Met at 40ppm gave the highest mean values of Na+, Mg+2 and Fe content. Sids1 surpassed Gemmeiza7 in K+, Na+ and Fe.
At 1st growth stage MOH (20%) gave the highest mean value of Na+, Mg+2, Ca+2 and Fe content. 30% gave the maximum of K+ and K/Na ratio. At 2nd growth stage MOH (30%) gave the maximum mean values of K/Na ratio, Mg+2 and Ca+2 levels. MOH (20%) recorded the highest values of K+ and Fe content. Sids1 exceeded Gemmeiza7 in Ca+2 and Fe.
At the 1st growth stage Eth (400ppm) gave the highest mean values of K/Na ratio and Fe content but Eth (200ppm) recorded the highest records of K+ and Mg+2 contents. Sids1 exceeded Gemmeiza7 in K+, Na+, Ca+2 and Fe. At 2nd growth stage, the highest mean values of K+, K/Na ratio, Mg+2 and Ca+2 were recorded by Eth (200ppm). Eth (400ppm) gave the highest mean values of Na+ and Fe levels. Sids1 exceeded Gemmeiza7 in Na+, Ca+2 and Fe content. In contrast, Gemmeiza7 surpassed Sids1 in K+, K/Na ratio and Mg+2.
At 1st growth stage, SA (100ppm) gave the highest values of K+, Na+, Ca+2 and Fe level. Sids1 surpassed Gemmeiza7 in K+, K/Na ratio, Ca+2 and Fe content. At 2nd growth stage, SA (100ppm) gave the maximum rates of K+, Na+, K/Na ratio and Fe content. SA 25ppm gave the maximum values of Mg+2 and Ca+2 level. However, Sids1 exceeded Gemmeiza7 in Na+, Ca+2 and Fe content.
8. Yield biochemical constituents.
8.1. Proteins content.
CaCl2 (0.2%) gave the maximum mean values of total and insoluble proteins. Total protein was obtained at 40ppm PA. Met 20ppm gave the highest soluble protein content. MOH (10%) gave the highest mean values of total and insoluble proteins. The highest mean value of soluble protein was recorded at 300ppm Eth. Gemmeiza7 surpassed Sids1 in total and insoluble proteins. The highest mean values of total and insoluble proteins recorded at SA (25ppm). Sids1 surpassed Gemmeiza7 at all protein parameters.
8.2. Minerals content in grains.
CaCl2 (0.8%) gave the highest mean values of K+, Na+ and Zn. CaCl2 (0.4%) gave the highest mean values of K/Na ratio and Fe. The highest Ca+2 content was introduced by 0.2% CaCl2. Sids1 exceeded Gemmeiza7 in K/Na ratio, Fe and Zn.
PA (40ppm) gave the highest mean values of K+, Na+, K/Na ratio, Ca+2, Fe and Zn. Sids1 exceeded Gemmeiza7 in Ca+2 and Fe content. Met (20ppm) gave the highest values of K+, K/Na ratio, Ca+2 and Zn. Na+ and Fe mean values were recorded by Met (60ppm). Sids1 exceeded Gemmeiza7 in K/Na ratio and Zn.
MOH (30%) gave the maximum mean values of K+, Na+, K/Na ratio and Ca+2. Gemmeiza7 surpassed Sids1 in Na+, Ca+2, Fe and Zn.
Eth (400ppm) gave the highest values of K+ and K/Na ratio. Eth (300ppm) gave the highest records of Na+, Ca+2, Fe and Zn. Sids1 exceeded Gemmeiza7 in K/Na ratio and Fe but Gemmeiza7 surpassed Sids1 in K+, Na+ and Zn.
SA (100ppm) gave the highest mean values of Na+, K+, Ca+2, Fe and Zn. Also Gemmeiza7 exceeded Sids1 in Fe and Zn content.
9. Yield.
0.8% CaCl2 gave the maximum mean values of grain and protein yield.
PA and Met (60ppm) gave the maximum mean values of grain yield and protein yield. Gemmeiza7 exceeded Sids1 in grain and protein yield after treatment with PA. Sids1 surpassed Gemmeiza7 in grain and protein yield after Met treatment.
The maximum values of plant height and grain yield were recorded by MOH (20%). Gemmeiza7 exceeded Sids1 in plant height and grain yield.
Eth (300ppm) increased grain and protein yield. Sids1 exceeded Gemmeiza7 in grain yield when Eth applied.
SA (100ppm) gave the highest mean value of plant height but the maximum mean value of grain and protein yield were given by SA (25ppm). Sids1 surpassed Gemmeiza7 in grain and protein yield.