Thesis (Ph.D)-Cairo University, 2024.

Bibliography: pages 292-263.

Quinoa is known to be more productive under saline conditions than most food
crops; they differ in their tolerance to salinity. Variability within quinoa genotypes
does not allow an efficient selection. Gamma rays were used to broaden genetic
variability, to practice an efficient selection in the M mutated generation. The main

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objective of the present study was to induce new mutants of quinoa, of high seed yield
and good quality under salinity-affected soil conditions of Egypt. A preliminary
experiment proved that the proper dose for the induction of useful mutations is 250
Gy; accordingly, we used it to irradiate the 19 quinoa genotypes. Laboratorial and
green house experiments were also conducted to evaluate the 19 quinoa genotypes
under elevated salinity levels (3000, 6000, and 9000 ppm NaCl) at different growth
stages. At germination and seedling stages, the four most salinity-tolerant quinoa
genotypes under all studied salinity stress conditions were Rainbow-2, Ql3, RH, and
KvlSRA2. In pots experiment, based on salinity tolerance index (STI) calculated
across all studied traits at age of 45 days, the five genotypes were tolerant to all salinity
stress levels. Field experiments were conducted during the three growing seasons
2018/2019, 2019/2020 and 2020/2021 at the Experimental Farm of the Ras Sudr
Station, Desert Research Center, South Sinai Governorate to evaluate 19 quinoa
genotypes, non-irradiated and irradiated in the M , M and M generations for

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agronomic, seed yield and its attributes. Field evaluation of 19 non-irradiated quinoa
genotypes across three seasons under salinity-affected soil conditions of Ras Sudr
showed wide differences for all studied traits. The promising genotype(s) for each trait
were identified. The highest seed yield/fed was recorded by the genotype Q13
followed by Di-17. The traits, that showed high genetic advance, high heritability and
a significant and positive correlation coefficient with seed yield/plant (chlorophyll
concentration index, branches/plant, inflorescences/plant, leaf area, inflorescence
weight), showed also wide variability among quinoa genotypes at the phenotypic and
genotypic levels and therefore are recommended as selection criteria for salinity
tolerance of quinoa in the field. Irradiation of the 19 quinoa genotypes caused, in the
M generation, a significant decrease in all studied traits, except in days to flowering

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and seeds/plant, which increased. Maximum gain from selection in M ’s for seed yield

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would be expected to be 15.45% from G-l3 (I) followed by 11.71% from R-103 (I).
Field evaluation of 12 putative mutants (selected in M ) and their 12 parents under

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salinity-affected soil conditions showed superiority of the mutants to their parents in
seed yield per feddan ranging from 1% for RH-S to 26.8% for Chipaya-S. The mutants
recorded significantly higher means than their parents for nine amino acids. The
molecular marker SCoT proved that the mutants are genetically different from their
parents and could be offered to plant breeders for use in the future.

كان الهدف الأساسى للدراسة هو استحداث طفرات جديدة من الكينوا ذات محصول بذور وجودة عاليين تحت ظروف التربة المتاثرة بالملوحة فى مصر. صممت التجارب الحقلية فى المزرعة التجريبية برأس سدر محافظة جنوب سيناء لتقييم 19 تركيب وراثى غير المشععة والمشععة فى الأجيال الطفورية الأول والثانى والثالث. تم تحديد التراكيب الوراثية الواعدة تحت كل صفة. التقييم الحقلى لعدد 12 طفرة محتملة وعدد 12 أب لهذه الطفرات تحت ظروف تربة متأثرة بالملوحة أظهر تفوقا للطفرات على أبائها فى محصول بذور الفدان تراوح بين 1% و26.8%. سجلت الطفرات متوسطات اعلى معنويا على ابائها فى تسعة احماض امينية. أثبت المعلم الجزيئى SCoT أن الطفرات مختلفة وراثيا عن أبائها ويمكن للمربى الاستفادة منها مستقبليا.

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