pistil length as indicator of ovule stages and use of length and width means of ovule stages to...

Pistil Length as Indicator of Ovule Stages and Use of Length and Width Means of Pistil Length as Indicator of Ovule Stages and Use of Length and Width Means of Ovule Stages to Determine if Fibonacci Sequence is obtained in RC Ovule Stages to Determine if Fibonacci Sequence is obtained in RC Brassica rapa Brassica rapa L. L. Samad Syed*, and Bruce Smith Samad Syed*, and Bruce Smith Department of Biological Sciences, York College of Pennsylvania Department of Biological Sciences, York College of Pennsylvania Introduction Brassica rapa is a member of the mustard family and is closely related to many early spring, late fall vegetable crops e.g., cabbage, brussel sprouts, and broccoli. For decades it has been a favorite choice for studies in genetics, morphology, and molecular biology (Smith, 1991). Quantitative studies have provided evidence for phylogenetic interpretations including early ovule comparisons within the haploid phase of dicot life histories (Smith, 1973). Purpose The purposes are: to compare ovule development in B. rapa by measuring the lengths and widths of stages and then compare these stages to easily obtained pistil lengths (Smith, 1971, 1973). Finally, to compute Fibonacci sequence which can be obtained after two starting values, each being the sum of the two preceding numbers e.g., Fn = Fn−1 + Fn−2 with F1=1 and F2=2 (1,1,2,3,5,8,13,21,…) (Boeyen, 2003). Once measured, the means of each developmental stage will be used to determine if the Fibonacci golden ratio can be obtained. Methods and Materials RC Brassica rapa seeds and the necessary equipment needed to grow them under constant light in YCP greenhouse Custom dissecting equipment for dissecting ovules Fixative, Alcohol series, Herr Fluid Clearing Technique: Fix the flowers using FPA50 (formulin, propionic acid) (min. of 24hrs) Decant FPA50 to replace it with 70% Ethyl Alcohol (ETOH70) Dehydration Series: 70→80→90→95→100% ETOH→ HERR Fluid Results Conclusion Megasporo-gametogenesis stages were successfully measured and compared to pistil length from which they were taken (see Table 2). The Fibonacci sequence and the golden spiral was obtained from each of the developmental stages (Table 3). Work Cited Boeyen, J. C. 2003. Number patterns in Nature. Crystal Engineering 6(4):167-185. Smith, B.B. 1991. Comparisons of Early Ovule Development through Megagametogenesis in Rapid-Cycling Brassica rapa L. And B.campestris L. using the Herr Clearing Techniques. Springer-Verlag, New York, Berlin Smith, B.B. and J.M. Herr, Jr. 1971. Ovule Development, Megagametogenesis, and Early Embryogeny in Ammania coccinea Rothb. The Journal of Elisha Mitchell Scientific Society. Vol. 87:No. 4. Smith, B.B. 1973. The Use of a new Clearing Technique for the Study of Early Ovule Development, Megasporogenesis, and Megagametogenesis in Five Species of Cornus L. American Journal of Botany. 60(4): 322-338. Acknowledgements I would like to thank Dr. Bruce Smith, Dr. Bradley Rehnberg & Dr. Karl Kleiner for their support and guidance with this project. Ovule Stages Meiotic Divisions (Megasporogenesis) A. MMC (Megasporo Mothercell)(2n) B. Dyad C. Tetrad (n) Mitotic Divisions (Megagametogenesis)(n) D. FM (Functional Megaspore) E. 2-Nucleate F. 4-Nucleate G. 8-Nucleate B A F E D C G Ovul e Pistil length

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Page 1: Pistil Length as Indicator of Ovule Stages and Use of Length and Width Means of Ovule Stages to Determine if Fibonacci Sequence is obtained in RC Brassica

Pistil Length as Indicator of Ovule Stages and Use of Length and Width Means of Ovule Stages Pistil Length as Indicator of Ovule Stages and Use of Length and Width Means of Ovule Stages

to Determine if Fibonacci Sequence is obtained in RC to Determine if Fibonacci Sequence is obtained in RC Brassica rapaBrassica rapa L. L. Samad Syed*, and Bruce SmithSamad Syed*, and Bruce Smith

Department of Biological Sciences, York College of PennsylvaniaDepartment of Biological Sciences, York College of PennsylvaniaIntroductionBrassica rapa is a member of the mustard family and is closely related to many early spring, late fall vegetable crops e.g., cabbage, brussel sprouts, and broccoli. For decades it has been a favorite choice for studies in genetics, morphology, and molecular biology (Smith, 1991).

Quantitative studies have provided evidence for phylogenetic interpretations including early ovule comparisons within the haploid phase of dicot life histories (Smith, 1973).

PurposeThe purposes are: to compare ovule development in B. rapa by measuring the lengths and widths of stages and then compare these stages to easily obtained pistil lengths (Smith, 1971, 1973). Finally, to compute Fibonacci sequence which can be obtained after two starting values, each being the sum of the two preceding numbers e.g., Fn = Fn−1 + Fn−2 with F1=1 and F2=2 (1,1,2,3,5,8,13,21,…) (Boeyen, 2003).

Once measured, the means of each developmental stage will be used to determine if the Fibonacci golden ratio can be obtained.

Methods and MaterialsRC Brassica rapa seeds and the necessary equipment needed to grow them under constant light in YCP greenhouse

Custom dissecting equipment for dissecting ovules

Fixative, Alcohol series, Herr Fluid

Clearing Technique:

Fix the flowers using FPA50 (formulin, propionic acid) (min. of 24hrs)

Decant FPA50 to replace it with 70% Ethyl Alcohol (ETOH70)

Dehydration Series:

70→80→90→95→100% ETOH→ HERR Fluid

Results ConclusionMegasporo-gametogenesis stages were successfully measured and compared to pistil length from which they were taken (see Table 2).

The Fibonacci sequence and the golden spiral was obtained from each of the developmental stages (Table 3).

Work Cited

Boeyen, J. C. 2003. Number patterns in Nature. Crystal Engineering 6(4):167-185.

Smith, B.B. 1991. Comparisons of Early Ovule Development through Megagametogenesis in Rapid-Cycling Brassica rapa L. And B.campestris L. using the Herr Clearing Techniques. Springer-Verlag, New York, Berlin

Smith, B.B. and J.M. Herr, Jr. 1971. Ovule Development, Megagametogenesis, and Early Embryogeny in Ammania coccinea Rothb. The Journal of Elisha Mitchell Scientific Society. Vol. 87:No. 4.

Smith, B.B. 1973. The Use of a new Clearing Technique for the Study of Early Ovule Development, Megasporogenesis, and Megagametogenesis in Five Species of Cornus L. American Journal of Botany. 60(4): 322-338.

Acknowledgements

I would like to thank Dr. Bruce Smith, Dr. Bradley Rehnberg & Dr. Karl Kleiner for their support and guidance with this project.

Ovule Stages

Meiotic Divisions (Megasporogenesis)

A. MMC (Megasporo Mothercell)(2n)

B. Dyad

C. Tetrad (n)

Mitotic Divisions (Megagametogenesis)(n)

D. FM (Functional Megaspore)

E. 2-Nucleate

F. 4-Nucleate

G. 8-Nucleate