1. -Arabidopsis thaliana is a member of the Brassicaceae family that can be found nearly worldwide (TAIR, 2008). -Ecotypes of A. thaliana have been shown to vary in flowering time in different climates and in response to different environments (TAIR, 2008). -Variation in flowering may show differences in the haploid generation; specifically the size of the megagametophyte. -Megagametogenesis is the development of a functional megaspore into an embryonic sac. The four stages being researched are the Functional Spore, 2- Nucleate, 4-Nucleate, and 8-Nucleate. -Two ecotypes with divergent environments were chosen for this study. One from an area of rolling foothills in Russia with a severe climate and significantly low precipitation and another from the busy city of Seattle, Washington with an oceanic climate and moderate amounts of precipitation. -The Fibonacci sequence is used to compare the mean length/width ratio of the measured stages. Fibonacci provided a means of determining if there was a difference in the two ecotypes relative to when their Fibonacci phi is reached at the 10th, 11th (1.618), or 18th divisions (1.6180339) respectively. -For these expressions of Phi to appear, the mean width value must equal 20-54.5% of the mean length value to achieve 1.618 at the 11 th division. It must equal 10-50.5% of the mean length to achieve 1.6180339 at the 18 th division. Introduction Objective: To determine if the two divergent climates and environments will have a significant effect on megagametogenesis on the two selected ectoypes Does Global Location Affect the Size of Female Megagametophytic Stages in Arabidopsis thaliana (L) Ecotypes? Lindsay Allen Department of Biology, York College Methods Seeds were chosen from Seattle and Russia Carolina Biological rapid cycling planting materials were used Collected flowers and stored in FPA50 Dehydrated in EtOH series (70- 100%) and stored in Herr fluid Nikon Eclipse 80i phase contrast microscope with Nikon DS-Ri1 camera and NIS elements imaging software used for imaging Minimum of 10 measurements made per haploid stage for each ecotype and used for Fibonacci analysis Results Mean Width Seattle Mean Width Russia Mean Length Seattle Mean Length Russia Reached Phi (1.6180339) Seattle Reached Phi (1.6180339) Russia Percent mean length:width ratio Seattle Percent mean length:width ratio Russia Functional Megaspore 10.717.5516.3416.6618 th division 65.5445.32 2-Nucleate11.5510.7023.2023.2518 th division 49.7446.02 4-Nucleate12.7812.9239.0739.9418 th division 32.7132.35 8-Nucleate14.2415.1155.1144.8618 th division 25.8433.68 Conclusions Literature Cited Acknowledgments -ABRC. 2009. The Ohio State University. Available from http://www.abrc.osu.edu/.http://www.abrc.osu.edu/ -Smith, B.B. 1973. The use of a new clearing technique for the study of early ovule development,megasporogenesis,and megagametogensis in five species of Cornus L. American Journal of Botany 60(4): 322-338. -Smith, B.B. 1975. A quantitative analysis of the megagametophyte of five species of Cornus L. American Journal of Botany. (62)4: 387-394. -The Arabidopsis Information Resource. (TAIR). 2008. Carnegie Institution of Washington Department of Plant Biology. Stanford, California. http://www.arabidopsis.org/index.jsp. I would like to thank Dr Bruce Smith for his constant support and guidance throughout the completion of this project. Figure 2. 2-Nucleate stage for Russia (left) and Seattle (Right). Figure 1. Functional Megaspore stage for Russia (left) and Seattle (right). Rationale Previous research observed early ovule developmental stages of five species of Cornus L. using the Herr clearing technique. Differences between the species in these stages suggested the removal of C. florida from the genus Cornus (Smith, 1973). Similar research is necessary for all ecotypes of A. thaliana. To determine if the stages met the 18 division of Phi, the mean length and width were added in a Fibonacci series, then divided by the mean length after each new number in the series to ascertain at what division Phi (1.6180339) would be reached. Fibonacci Series addition is expressed as F n = F n-1 +F n-2 Addition of the two prior numbers, beginning with mean length and width for each stage, yields the next number in the series. Each division is expressed as (W+L)/L, for a ratio. Future Research Conduct a similar study on other ecotypes of A. thaliana to determine the relationship of an ecotypes development in terms of its environment. This could include growing ecotypes in their natural environments or growing in an opposite environment. -The 3-decimal phi, 1.618 and 7-decimal phi, 1.6180339, were both reached at the 10 th /11 th and 18 th divisions, respectively, for each ecotype. -Based upon the analysis of the numerical data collected, it can be concluded that the divergent environments did not affect the size of the female gametophytic stages. -The location and the environment of the two ecotypes had no significant affect on their developmental stages. FM_RussiaDivision 7.55 16.662.20662251661 24.211.45318127252 40.871.68814539453 65.081.59236603874 105.951.62799631225 171.031.61425200576 276.981.61948196227 448.011.61748140668 724.991.61824512859 11731.617953351110 1897.991.618064791111 3070.991.618022223512 4968.981.618038482713 8039.971.618032272214 13008.951.618034644415 21048.921.618033738316 34057.871.618034084417 55106.791.618033952218 89164.661.618034002719 144271.451.618033983420 233436.111.618033990821 377707.561.618033988022 611143.671.618033989023 988851.231.618033988624 1599994.91.618033988825 2588846.131.618033988726 FM_SeattleDivision 10.71 16.341.52567693741 27.051.6554467562 43.391.6040665433 70.441.6234155344 113.831.6159852365 184.271.6188175356 298.11.6177348467 482.371.6181482728 780.471.6179903399 1262.841.61805066210 2043.311.6180276211 3306.151.61803642112 5349.461.6180330613 8655.611.61803434414 14005.071.61803385315 22660.681.61803404116 36665.751.61803396917 59326.431.61803399618 95992.181.61803398619 155318.611.6180339920 251310.791.61803398821 406629.41.61803398922 657940.191.61803398923 1064569.591.61803398924 1722509.781.61803398925 2787079.371.61803398926 2N_RussiaDivision Width10.7 Length23.252.17289719631 33.951.46021505382 57.21.68483063333 91.151.59353146854 148.351.62753702695 239.51.61442534556 387.851.61941544897 627.351.61750676818 1015.21.61823543489 1642.551.617957052810 2657.751.618063377111 4300.31.618022763612 6958.051.618038276413 11258.351.618032351014 18216.41.618034614315 29474.751.618033749816 47691.151.618034080017 77165.91.618033953918 124857.051.618034002119 202022.951.618033983720 3268801.618033990721 528902.951.618033988022 855782.951.618033989023 1384685.91.618033988624 2240468.851.618033988825 3625154.751.618033988726 2N_ SeattleDivision Width11.54 Length23.202.01039861351 34.741.4974137932 57.941.6678180773 92.681.5995857784 150.621.6251618475 243.31.615323336 393.921.6190711067 637.221.6176380998 1031.141.6181852429 1668.361.6179762210 2699.51.61805605511 4367.861.6180255612 7067.361.61803720813 11435.221.61803275914 18502.581.61803445815 29937.81.61803380916 48440.381.61803405717 78378.181.61803396318 126818.561.61803399919 205196.741.61803398520 332015.31.6180339921 537212.041.61803398822 869227.341.61803398923 1406439.381.61803398924 2275666.721.61803398925 3682106.11.61803398926 Figure 3. Fibonacci sequence tables for Functional megaspore (Russia), Fuctional Megaspore (Seattle), 2-Nucleate (Russia) and 2-Nucleate (Seattle.) Table 1. Summary of all data collected