Recognition Of Patterns Of Trait Inheritance In Plant Hybridization
Recognition of Patterns of Trait Inheritance in Plant Hybridization: Pisum sativum
Daylan Hartranft, student
Bachelor of Science in Biology
Key words: Pea plant, Monohybrid, Dihybrid, Independent assortment, Dominant, Recessive
Running title: Patterns of Inheritance
# Figures: 3
# Tables: 2
Correspondence to: Daylan Hartranft
Introduction
Plants have noticeable trait inheritance; however, the method of transmission is unknown. Understanding this would allow creation of crops with desired traits.
Methods
The pea plant, Pisum sativum, was used due to its distinctly varying traits. Through artificial cross-fertilization and self-fertilization, three generations of hybrids expressing varying traits were created. Monohybrid crosses were done in comparison of one trait; dihybrid crosses were done in comparison of two traits simultaneously. The numbers of plants expressing dominant and recessive traits were counted.
Results
In the monohybrid F2 generation, the ratio of dominant to recessive expression was 3:1 for each trait, dominant meaning the trait expressed in the first hybrid generation and recessive meaning the trait hidden in the first hybrid generation. In the dihybrid F2 generation, the ratio was 9:3:3:1 for dominant with dominant, dominant with recessive, recessive with dominant, and recessive with recessive traits expressed.
Discussion
Traits were found to independently assort, meaning transmission of one trait was not dependent on transmission of a second trait. The observance of recessive traits being hidden in one generation and reappearing in the next is proof that even if not physically expressed, a plant may carry the character for both trait variations. A plant must get one trait character from each parent. If a dominant character is present, the dominant trait will be expressed; if only recessive characters are present, the recessive trait will be expressed. The understanding of a law of trait inheritance will allow
Daylan Hartranft, student
Bachelor of Science in Biology
Key words: Pea plant, Monohybrid, Dihybrid, Independent assortment, Dominant, Recessive
Running title: Patterns of Inheritance
# Figures: 3
# Tables: 2
Correspondence to: Daylan Hartranft
Introduction
Plants have noticeable trait inheritance; however, the method of transmission is unknown. Understanding this would allow creation of crops with desired traits.
Methods
The pea plant, Pisum sativum, was used due to its distinctly varying traits. Through artificial cross-fertilization and self-fertilization, three generations of hybrids expressing varying traits were created. Monohybrid crosses were done in comparison of one trait; dihybrid crosses were done in comparison of two traits simultaneously. The numbers of plants expressing dominant and recessive traits were counted.
Results
In the monohybrid F2 generation, the ratio of dominant to recessive expression was 3:1 for each trait, dominant meaning the trait expressed in the first hybrid generation and recessive meaning the trait hidden in the first hybrid generation. In the dihybrid F2 generation, the ratio was 9:3:3:1 for dominant with dominant, dominant with recessive, recessive with dominant, and recessive with recessive traits expressed.
Discussion
Traits were found to independently assort, meaning transmission of one trait was not dependent on transmission of a second trait. The observance of recessive traits being hidden in one generation and reappearing in the next is proof that even if not physically expressed, a plant may carry the character for both trait variations. A plant must get one trait character from each parent. If a dominant character is present, the dominant trait will be expressed; if only recessive characters are present, the recessive trait will be expressed. The understanding of a law of trait inheritance will allow