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Genetic studies in populations of Collinsia parviflora Dougl.ex Lindl. (Scrophulariaceae) by Gerda Rosa Krause Sc. (Hon.), University of British Columbia, 1975 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in The Faculty of Graduate Studies Department of Botany We accept this thesis as conforming to the required standard The University of British Columbia Gerda Rosa Krause, 1978 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of The University of British Columbia 2075 Wesbrook Place Vancouver, Canada V6T 1W5 Date - ii - Abstract The Collinsia populations in southwestern British Columbia and northwestern Washington show considerable variation in leaf and flower characters both within and between populations. One of the purposes of this study was to determine the genetic mechanisms con• trolling some of these characters. Two leaf polymorphisms were studied. They were the presence or absence of purple anthocyanin spots on the surface of the leaves and the presence or absence of a silvery sheen, also on the surface of the leaves. Each was shown to be controlled by a single gene with two alleles. The spotted leaf character was dominant over the un• spotted leaf character and the silvery sheen was dominant over the normal green leaf character. Flower size was also studied and shown to be controlled by polygenic inheritance. Two mutant flower colours, white and magenta, are found in this region of study, in addition to the normal blue colour. The inher• itance of flower colour was not conclusively determined but the data indicate that two genes may be involved, one controlling the pro• duction of the magenta pigment from the colourless precursor and one controlling the production of the blue pigment from the magenta one. Another purpose of this work wa6 to determine the chromosome number of the Collinsias in this area. Both diploid (n=7) and tetraploid (n=l*f) counts have been reported. Six populations were studied and all were found to be tetraploid. - iii - Finally, the cytological and genetic data were used in con• junction with morphological data to revise the taxonomy of the Collinsias in this region of study. Most authors divide them into two species, £. grandiflora Dougl, ex Lindl, and parviflora Dougl, ex Lindl, However this study indicates that they are only one highly variable species, C_, parvi flora. - iv - Table of Contents Page Abstract ii Table of Contents iv List of Tables v List of Figures and Illustrations vii Acknowledgement ix Chapter 1 Introduction a) Taxonomy 1 b) Cytogenetics 2 c) Genetics 3 d) Materials and Methods 5 Chapter 2 Leaf Spot Polymorphism a) Introduction 10 b) Materials and Methods 13 c) Results 15 d) Discussion 21 Chapter 3 Silvery Leaf Polymorphism a) Introduction 24 b) Materials and Methods 2If c) Results 26 d) Discussion 33 Chapter k Flower Colour Mutants a) Introduction 3k fc) Material and Methods 38 c) Results ifO d) Discussion k9 Chapter 5 Inheritance of Flower Size a) Introduction 51 b) Materials and Methods 53 c) Results 57 d) Discussion 73 Chapter 6 Chromosome Counts a) Introduction 77 fc) Materials and Methods 78 c) Results 78 d) Discussion 79 Chapter 7 Taxonomy a) Introduction 81 b) Materials and Methods 81 c) Results 85 d) Discussion 90 Bibliography Vita - v - List of Tables Page Table I Population numbers of the Collinsia populations used in the crossing experiments •••••••••••••••• 7 Table II Si and F^ progeny of the crosses involving the spotted leaf character • • • 16 Table III S2 and Fp progeny of heterozygous spotted S^ and F^ plants ••••••••• 18 Table IV Sg and Fg progeny of unspotted S^ and Fx plants ••••••• 19 Table V Sg and Fg progeny of homozygous spotted S, and F, plants ••••••••••••• 22 Table VI S^ and F]_ progeny of the crosses involving the silvery-leaf character • • • 27 Table VII S2 and F2 progeny of the crosses involving the silvery-leaf character • • • 29 Table VIII F2 progeny of the #11 green (9) x #25 silvery (d1) cross ••••••• Table IX S^ and So progeny of the populations used in the crosses involving flower colour 41 Table X F^ and Fp progeny resulting from crosses between blue-flowered and white-flowered plants •••••••••••••••••• 43 Table XI F2 progeny of the #22 (?) x #9 blue (<3) cross that showed segregation for flower colour •••••••••••••••••• kk Table XII F^ and F2 progeny of the crosses between blue-flowered plants and magenta-flowered plants •••••«•••••••••••• 46 Table XIII Fi and F2 progeny of the crosses between white-flowered magenta-flowered plants • • 48 Table XIV Corolla length classes assigned to C, parviflora and C. grandiflora by various authors •••••••••••••• 32 Table XV Populations of C. barviflora used in the study of flower size variation . • , 55 - vi Table XVI Mean flower sizes and sample sizes of the populations graphed in Fig. 17 Table XVII Mean flower sizes and sample sizes of the populations graphed in Fig. 18 Table XVIII Mean flower sizes and sample sizes of the populations graphed in Fig. 19 Table XIX Mean flower sizes and sample sizes of the populations graphed in Fig. 20 Table XX Mean flower sizes and sample sizes of the populations graphed in Fig. 21 Table XXI Mean flower sizes and sample sizes of the populations graphed in Fig. 22 Table XXII Mean flower sizes and sample sizes of the populations graphed in Fig. 23 Table XXIII Mean flower sizes and sample sizes of the populations graphed in Fig. 24 Table XXIV Data sheet for population _________ Table XXV Summary of the variation among the populations studied .... • ..• - vi j - List of Figures and Illustrations Page Figure 1 Map of the study area showing the local• ities from which seeds were collected • • • 6 Figure 2 Collinsias growing in 5-inch pots • • • • • 8 Figure 3 Collinsias growing closely spaced in shallow flats ••••••••••••••• 8 Figure k Plants with and "without purple antho- cyanin spots on the upper epidermis of the leaves •••••••••••••••• 11 Figure 5 Plant showing the faint-spotting character ••••••••••••••••• 12 Figure 6 Plant showing the heavy-spotting character ••••••••••••••••• Ik Figure 7 Carlos Island plants showing the silvery-leaf character •••••••••• 25 Figure 8 Carlos Island plants showing normal green leaves ••••••••••••••• 25 Figure 9 Silvery, green and intermediate' plants • 31 Figure 10 A magenta flower from the Elk Falls population •••••••••••••••• 35 Figure 11 An albino flower from the Mt» Douglas Park population •••••••••••••• 35 Figure 12 A population with anthocyanin pigments in the leaves ••••••••••••••• 37 Figure 13 The Mt, Douglas Park population with yellow leaves ••••••••••••••• 37 Figure Ik The F2 generation in the cross between white and magenta-flowered plants, showing segregation for the three flower colours • k? Figure 15 The variation in flower size between the five populations used in study. From left to right: Elk Falls, Jack Point, Nanoose Hill, Botanie Valley, Lindeman Lake • • • • 3k Figure 16 A Colljnsia flower showing the angle at which measurements were taken • • • • • 56 - viii - Page Figure 1? Graph comparing flower sizes of the five populations in the first (parental) generation ••••••••••••••••• 58 Figure 18 Graph comparing flower sizes of the five populations in the second (S,) generation • 60 Figure 19 Graph comparing flower sizes of the five populations in the third (S^) generation • • 62 Figure 20 Graph comparing the flower sizes of Lindeman Lake (#6) and Jack Point (#11) populations with a possible hybrid between them •••••••••••••••• 65 Figure 21 Graph comparing the flower sizes of the hybrids between populations from Botanie Valley (#22) and Nanoose Hill (#9) with their parental populations ••••••••• 67 Figure 22 Graph comparing the flower sizes of the hybrids between populations from Botanie Valley (#22) and Jack Point (#11) with their parental populations ••••••••• 69 Figure 23 Graph comparing the flower sizes of hybrids between populations from Lindeman Lake (#22) and Elk Falls (#17) with their parental populations •••••••••••• 71 Figure 24 Graph comparing the flower sizes of hybrids between populations from Mt. Douglas Park (#2) and Elk Falls (#17) with their parental populations •••••••••••• 74 Figure 25 A pollen mother cell from the Nanoose Hill population showing a chromosome number of 2n s 14 II 80 Figure 26 A pollen mother cell from the Carlos Island population showing a chromosome number of 2n = 14 II 80 Figure 27 The leaf characters of the Botanie Valley population ••••••••••••• 87 Figure 28 The leaf characters of the Jack Point population ••••••••••••••••• 87 Acknowledgement I would like to express my gratitude to my director, Dr. F. R. Ganders and to my committee, Dr. C. J. Marchant and Dr. A, J. F. Griffiths for their willing assistance, discussion and criticism during the research and their help in preparing the manuscript; to Dr. K. I. Beamish, Dr. C. 0. Person and Dr, B. A. Bohm for advice and assistance with various parts of this thesis; to Mr. Ken Carey and Dr. W. B. Schofield for collecting Collinsia seeds; and to the Department of Botany for the use of equipment and facilities. I would also like to acknowledge receipt of two National Research Council Scholarships (1975/76 and 1976/77) and thank Mrs. Lorraine Wiebe for typing the manuscript. Finally, I would like to thank my husband, Eric, for all his encouragement and infinite patience. Chapter 1 Introduction Taxonomy The blue-flowered Collinsias in southwestern British Columbia and northwestern Washington have generally been divided into two species.

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