Evaluation of some cowpea accessions for environmental stress tolerance and studies on the nature and genetics of tolerance /
Taha Adly Ahmed Ibrahim,
Evaluation of some cowpea accessions for environmental stress tolerance and studies on the nature and genetics of tolerance / تقييم بعض سلالات اللوبيا لتحمل الإجهاد البيئى ودراسات على طبيعة ووراثة التحمل by Taha Adly Ahmed Ibrahim ; Supervisors Dr. Ahmed Abdel-Moneim Hassan, Dr. Khaled El-Sayed Ali Abdel-Ati, Dr. Khaled Adly Mohamed Khaled. - 171 pages : illustrations ; 25 cm. + CD.
Thesis (Ph.D)-Cairo University, 2025.
Bibliography: pages 152-171.
The present study was conducted at the Agricultural Experiment Station of the Faculty of Agriculture, Cairo University, Giza, Egypt, during 2021&2023 under open field conditions. Seventy cowpea accessions were evaluated for drought tolerance based on their characters, especially drought tolerance. In second screening, based on results and percentage change of various characters determined in the first screening, 20 genotypes were selected and evaluated. Six genotypes were selected based on first and second vegetative stage screening and were used to study drought tolerance based on physiological, anatomical and molecular characters. Seventy-five genotypes of cowpea were evaluated for heat tolerance. Ten genotypes were selected based on first vegetative stage screening and were used to study heat tolerance based on physiological and molecular characters. Nine genotypes were evaluated for salt tolerance. Results indicated that accessions TVU-14997, TVU-15304 and TVU-15306 recorded the highest drought tolerance based on their high levels of each of leaf greenness, average leaf area, photosynthesis efficiency, antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity, resulting in increasing seed yield per plant compared with other accessions. Genotypes TVU-14997 and TVU-15306 showed unique responses, highlighting genetic diversity in drought tolerance. Under drought condition, accession TVU-15306 had the highest value for thickness of the midvein, spongy tissue, dimension of vascular bundle and mean vessels diameter. Partial dominance was detected for each of low leaf greenness, low root fresh weight, high shoot fresh and dry weight, and root dry weight. Accessions TVU-17054, TVU-17064 and TVU-17137 recorded the highest heat stress tolerance based on their high levels of each of leaf greenness which increased photosynthesis efficiency, number of main branches, shoot dry weight, root dry weight, antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity. They were also characterized by low stomata conductance and transpiration rate that maintained water content in leaves resulting in increasing seed yield per plant compared with other accessions. For heat tolerance A 300 bp fragment (Primer 1) was unique to the most heat-tolerant genotype (TVU-17137), while a 395 bp fragment (Primer 2) was exclusive to TVU-17096, which also exhibited relatively early flowering. Partial dominance was detected for each of high leaf greenness and high root dry weight in cross TVU-17137 × TVU-15303, low shoot fresh and dry weight and root fresh and dry weight in cross TVU-17064 × TVU-15303. Accessions TVU-15306, TVU-17064 and TVU-17137
recorded high salt stress tolerance based on their high values of each of average leaf area, leaf greenness which increased photosynthesis efficiency, and high levels of antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity. They were also characterized by low stomata conductance and transpiration rate. استهدفت الدراسة تقييم 70 سلالة وصنفا من اللوبيا لتحمل الجفاف. في التقييم الثاني بناءً على نتائج الصفات المختلفة التي تم قياسها في التقييم الأول والنسبة المئوية لمعدل الاختلاف، تم انتخاب 20 سلالة من اللوبيا وتقيمها، وتم أنتخاب 6 سلالات بناءً على التقييم فى مرحلة النموالخضرى الأول والثاني، وتم تقيمها لدراسة تحمل الجفاف على أساس فسيولوجي وتشريحي وجزيئي. تم تقييم 75 سلالة من اللوبيا لتحمل الحرارة. تم أنتخاب 10 سلالات بناءً على التقييم الأول فى مرحلة النمو الخضرى. تم تقييم 10 سلالات لتحمل الحرارة العالية على أساس فسيولوجي وجزيئي. تم تقييم 9 سلالات لتحمل الملوحة. أظهر السلالتان TVU-14997، و TVU-15306 أستجابة تشير إلى الاختلاف الوراثي فى تحمل الجفاف. سجلت السلالات TVU-17054 و TVU-17064 و TVU-17137 أعلى درجة تحمل للإجهاد الحراري بناءً على المستويات العالية لكل من أخضرارالأوراق مما ادى الى زيادة كفاءة التمثيل الضوئي، وعدد الفروع الرئيسية، والوزن الجاف للساق، والوزن الجاف للجذر، ومضادات الأكسدة، والمحتوى الفينولى، ومحتويات حمض الأبسيسك والبرولين ونشاط الكتاليز والبيروكسديز.
Text in English and abstract in Arabic & English.
Cowpea
اللوبيا
Cowpea drought tolerance heat tolerance, salt tolerance dominance number of genes heritability
633.33
Evaluation of some cowpea accessions for environmental stress tolerance and studies on the nature and genetics of tolerance / تقييم بعض سلالات اللوبيا لتحمل الإجهاد البيئى ودراسات على طبيعة ووراثة التحمل by Taha Adly Ahmed Ibrahim ; Supervisors Dr. Ahmed Abdel-Moneim Hassan, Dr. Khaled El-Sayed Ali Abdel-Ati, Dr. Khaled Adly Mohamed Khaled. - 171 pages : illustrations ; 25 cm. + CD.
Thesis (Ph.D)-Cairo University, 2025.
Bibliography: pages 152-171.
The present study was conducted at the Agricultural Experiment Station of the Faculty of Agriculture, Cairo University, Giza, Egypt, during 2021&2023 under open field conditions. Seventy cowpea accessions were evaluated for drought tolerance based on their characters, especially drought tolerance. In second screening, based on results and percentage change of various characters determined in the first screening, 20 genotypes were selected and evaluated. Six genotypes were selected based on first and second vegetative stage screening and were used to study drought tolerance based on physiological, anatomical and molecular characters. Seventy-five genotypes of cowpea were evaluated for heat tolerance. Ten genotypes were selected based on first vegetative stage screening and were used to study heat tolerance based on physiological and molecular characters. Nine genotypes were evaluated for salt tolerance. Results indicated that accessions TVU-14997, TVU-15304 and TVU-15306 recorded the highest drought tolerance based on their high levels of each of leaf greenness, average leaf area, photosynthesis efficiency, antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity, resulting in increasing seed yield per plant compared with other accessions. Genotypes TVU-14997 and TVU-15306 showed unique responses, highlighting genetic diversity in drought tolerance. Under drought condition, accession TVU-15306 had the highest value for thickness of the midvein, spongy tissue, dimension of vascular bundle and mean vessels diameter. Partial dominance was detected for each of low leaf greenness, low root fresh weight, high shoot fresh and dry weight, and root dry weight. Accessions TVU-17054, TVU-17064 and TVU-17137 recorded the highest heat stress tolerance based on their high levels of each of leaf greenness which increased photosynthesis efficiency, number of main branches, shoot dry weight, root dry weight, antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity. They were also characterized by low stomata conductance and transpiration rate that maintained water content in leaves resulting in increasing seed yield per plant compared with other accessions. For heat tolerance A 300 bp fragment (Primer 1) was unique to the most heat-tolerant genotype (TVU-17137), while a 395 bp fragment (Primer 2) was exclusive to TVU-17096, which also exhibited relatively early flowering. Partial dominance was detected for each of high leaf greenness and high root dry weight in cross TVU-17137 × TVU-15303, low shoot fresh and dry weight and root fresh and dry weight in cross TVU-17064 × TVU-15303. Accessions TVU-15306, TVU-17064 and TVU-17137
recorded high salt stress tolerance based on their high values of each of average leaf area, leaf greenness which increased photosynthesis efficiency, and high levels of antioxidant capacity, total phenols, abscisic acid and proline contents and catalase and peroxidase activity. They were also characterized by low stomata conductance and transpiration rate. استهدفت الدراسة تقييم 70 سلالة وصنفا من اللوبيا لتحمل الجفاف. في التقييم الثاني بناءً على نتائج الصفات المختلفة التي تم قياسها في التقييم الأول والنسبة المئوية لمعدل الاختلاف، تم انتخاب 20 سلالة من اللوبيا وتقيمها، وتم أنتخاب 6 سلالات بناءً على التقييم فى مرحلة النموالخضرى الأول والثاني، وتم تقيمها لدراسة تحمل الجفاف على أساس فسيولوجي وتشريحي وجزيئي. تم تقييم 75 سلالة من اللوبيا لتحمل الحرارة. تم أنتخاب 10 سلالات بناءً على التقييم الأول فى مرحلة النمو الخضرى. تم تقييم 10 سلالات لتحمل الحرارة العالية على أساس فسيولوجي وجزيئي. تم تقييم 9 سلالات لتحمل الملوحة. أظهر السلالتان TVU-14997، و TVU-15306 أستجابة تشير إلى الاختلاف الوراثي فى تحمل الجفاف. سجلت السلالات TVU-17054 و TVU-17064 و TVU-17137 أعلى درجة تحمل للإجهاد الحراري بناءً على المستويات العالية لكل من أخضرارالأوراق مما ادى الى زيادة كفاءة التمثيل الضوئي، وعدد الفروع الرئيسية، والوزن الجاف للساق، والوزن الجاف للجذر، ومضادات الأكسدة، والمحتوى الفينولى، ومحتويات حمض الأبسيسك والبرولين ونشاط الكتاليز والبيروكسديز.
Text in English and abstract in Arabic & English.
Cowpea
اللوبيا
Cowpea drought tolerance heat tolerance, salt tolerance dominance number of genes heritability
633.33