Numerical taxonomy of Portuguese Tronchuda cabbage and Galega kale landraces using morphological characters. J.S. Dias', A.A. Monteiro' & M.B. Lima'.
Euphytica 69 : 51-68,1993. ©1993 Kluwer Academic Publishers . Printed in the Netherlands .
Numerical taxonomy of Portuguese Tronchuda cabbage and Galega kale landraces using morphological characters
J.S. Dias', A .A. Monteiro' & M .B . Lima' 'Instituto Superior de Agronomia, Universidade Tecnica de Lisboa, Tapada da Ajuda, 1300 Lisboa, Portugal ; 2 Estacao Agronomica Nacional, Instituto Nacional de Investigacao Agraria, Quinta do Marques, 2780 Oeiras, Portugal Received 6 January 1993; accepted 8 June 1993
Key words: Brassica oleracea,
classification, landrace groups, morphology, Portuguese coles
Summary A morphological study was carried out to determine the relationships among Portuguese cole landraces using 58 accessions belonging to: (i) Portuguese Tronchuda cabbage (Brassica oleracea var. tronchuda Bailey syn . var. costata De Candolle, Couve Tronchuda) ; (ii) Portuguese Galega kale (B. oleracea var. acephala De Candolle, Couve Galega) ; and (iii) other economically less important coles such as Algarve cabbages (B. oleracea var. capitata L., Couve do Algarve or B. oleracea var. sabauda L ., Couve Repolho-lombarda do Algarve) . The cole accessions were collected from the growers, studied under field conditions during two consecutive years, and characterized using 46 morphological characters from seedling stage to ripe silique . Morphological data were analysed by numerical taxonomy techniques using UPGMA (Unweighted Pair Group Method Using Arithmetic Averages) and by principal component analysis (PCA) . Phenograms based on correlation and distance coefficients showed the existence of 8 main groups (A-H) . Five of these groups correspond to Tronchuda cabbage landraces : (A) "Couves de Tras-os-Montes" ; (B) "Couves do Minho" ; (C) "Couves from Central Portugal" ; (D) "Couve Portuguesa" ; (E) "Couves from Southern inland Portugal" . The three other groups correspond to : (F) cabbages; (G) miscellaneous coles ; and (H) Galega kales . Landrace groups are primarily associated with morphological differences among accessions and secondly with accession geographical origin. The interannual character variation did not affect the clustering patterns of the accessions and therefore the stability of landrace classification . PCA was congruent with the landrace groups defined by the phenograms and gave supplementary information on the usefulness of the characters for the definition of the various groups .
Introduction Portuguese coles are a unique group of vegetable crops very important for Portuguese horticulture owing to their excellent adaptation to prevalent climatic conditions, and good integration into small farming traditional cropping systems . Portuguese coles (Fig . 1) include : (i) Portuguese
Tronchuda cabbage (Brassica oleracea var . tronchuda Bailey syn . var . costata De Candolle, Couve Tronchuda) having a loose head, leaves with thick petioles and large veins, and variable pseudo-head size ranging from virtually a common cabbage to almost no head formation ; (ii) Portuguese Galega kale (B. oleracea var . acephala De Candolle, Couve Galega) having large leaves with long petioles
52
Fig. 1.
Some examples of the morphological variation of Portuguese coles : a- Penca de Mirandela ; b- Penca da Povoa; c- Couve Silveirin
ha ; d- Couve Portuguesa ; e- Couve Calguda; f- Couve Murciana .
53
(cont .) . Some examples of the morphological variation of Portuguese coles: g- Couve de Valhascos ; h- Couve Galega; i- Couve Repolho do Algarve . Fig. 1 .
forming no head, and a long stem reaching over 1 m high at mature stage before bolting ; (iii) other economically less important coles such as Algarve cabbages (B. oleracea var . capitata L., Couve do Algarve and B. oleracea var. sabauda L., Couve Re-
morphological variation within landraces making the identification of the prevalent morphotype a rather difficult task . The first systematic study of morphological char-
polho-lombarda do Algarve) two locally grown
acterization of the Portuguese coles was by Cerca (1946) and Miguel (1957) who studied 41 morpho-
white and savoy cabbage morphotypes. There are some difficulties in the grouping and
logical characters of seeds, seedlings, and adult plants from 32 accessions, for defining 5 ecotypes of
synonymy of the various landraces of Portuguese
Tronchuda cabbage : Penca de Chaves, Penca da Po-
Tronchuda cabbages and Galega kales grown in the different regions of Portugal, owing to the high di-
voa, Couve Portuguesa, Gloria de Portugal, and Couve Murciana ; plus Algarve cabbage (Couve do
versity of the morphotypes ranging from typical kales to nearly cabbage like ones . The little care the
Algarve) . This study included a relatively restricted number of collecting sites for cole landraces grown
growers have used in selecting and isolating the plants for seed production has resulted in a high
in Portugal, and the methodology used was unable
54
MINHO
2ii3 TRAS-OS 1 6 -MONTES
.5,16
4
0,11
1 2
•05
7
PORTO
5 21 23 24 00 022 48 • 9,301 •2 5 • • •2 6 28 27 31 • • 49 32
20 • : 7 19 9 6D 14,18
2 39,40 •5 1 W6 •4 42 6
36
33
5037" V
LISBON
51 43 • • 4 4 53
a 0 p
3Q ' O
AZORES
38
G3 o ~4 55
ALGARVE •5 8
Fig. 2. Map of Portugal with the geographic distribution of the accessions used in the present study . The black dots refer to the collection sites and the numbers refer to accessions listed in Table 1 .
55 to determine all the differences among the various
have gone through one generation of mass selec-
morphotypes. More recently Dias et al. (1992) characterized, by
tion, and 56 (ISA 471) and 57 (ISA 484) which are very common imported cultivars .
numerical taxonomy using nuclear RFLP data, a large collection of B. oleracea accessions including 31 Portuguese coles . In this study Portuguese Tron-
Character observation
chuda cabbage and Galega kale accessions formed a large and compact group containing no other cultivated brassicas . This group could be further divided into five subgroups each corresponding to a major area of cultivation . Based on these molecular
Fourty six morphological characters (Table 2) were observed on the 58 accessions . The selection of the characters was made by adapting the IBPGR descriptors (IBPGR, 1989) to numerical taxonomy
data Portuguese Tronchuda cabbages and Galega kales clustered according to their geographical ori-
methodology and to the characteristics of the mate-
gin and not to their morphological similarities .
and previous field observations of the material . To take into consideration the influence of differ-
Couve do Algarve was found to be highly similar to imported common cabbages forming a distinct group from Portuguese Tronchuda cabbages and Galega kales .
rial, taking into account the work of Cerca (1946)
ent soil and climatic conditions and of interannual morphological variation, sub-samples of the 58 accessions were grown in the same experimental field
The objectives of the present research on Portu-
during two successive years (1989/90 and 1990/91) .
guese coles are : (i) to determine the morphological
In August of each year the seeds were planted in
resemblance among the various landraces and to
multipot-trays filled with a peat-based substrate . The seedlings were planted out in September, at the
define the major landrace groups using numerical taxonomy ; (ii) to ascertain the influence of the interannual variation of the morphological characters on the stability of landrace grouping ; and (iii) to evaluate which are the most useful morphological characters for the definition of the various landrace groups .
5 leaf stage, at 60 x 60 cm spacing, in 58 plots of 60 plants each, corresponding to the 58 accessions . The experimental field was located at Batalha (120 km North of Lisbon) . Soil preparation, fertilizing, plant protection, and other growing practices were the usual for cabbage cultivation, managed with the objective of inducing a uniform and rapid plant growth and development .
Materials and methods
Group A characters (Table 2) were recorded in the field, from November to January, on 20 plants
Plant material
per accession randomly selected in each plot . Group B characters were observed, from Decem-
Fifty eight accessions including Portuguese coles
ber to July, after bolting, on 20 plants per accession left in each plot . For characters 29, 30, and 42 up to 40 plants were studied . For silique and seed obser-
representative of the main landraces and growing regions of Portugal, plus some imported cabbage cultivars grown in Portugal for long time, were used in the present study. Accession designation and their sources are listed in Table 1, and their geographical origin is shown in Fig. 2 . Seeds were collected directly from the growers . Simultaneously with seed collecting inquiries about brassica terminology, growing systems, and morphological differences were carried out . Exception to this rule are accessions 4 (ISA 444), 5 (ISA 453), 8 (ISA 600), 9 (ISA 454), 20 (ISA 500), and 42 (ISA 502), which
vations only the median part of the inflorescence raquis was used . Group C characters were studied before planting, at seedling stage, on 40 plants per accession randomly collected from the multipottrays .
Data handling and numerical taxonomy analysis The 46 characters scored for the 58 accessions for
56 Table 1 . Accessions used in the present study and their sourcesa Accession number Identification B. oleracea var . tronchuda (syn. costata) : I Penca de Chaves 2 Penca de Chaves 3 Penca de Chaves 4 Penca de Mirandela da Veia Branca (Pao de Acucar) 5 Penca de Mirandela Penca de Mirandela 6 7 Penca de Safres 8 Penca Espanhola 9 Penca da P6voa 10 Penca da Povoa 11 Penca da Povoa 12 Penca da Povoa 13 Penca da Povoa 14 Penca da Povoa 15 Coivao Coivao 16 17 Coivao Couve Gloria de Portugal 18 19 Couve Gl6ria de Portugal Couve Gl6ria de Portugal 20 21 Couve de Cortar 22 Couve da Cordinha Couve de Bolho 23 24 Couve Tronchuda Branca de Cantanhede 25 Couve de Castelo Viegas 26 Couve Calcuda 27 Couve Calcuda 28 Couve da Arrocha 29 Couve de Corte (Pe curto) Couve de Corte (Pe comprido) 30 31 Couve de Corte (Guia) Couve Silveirinha 32 33 Couve Portuguesa 34 Couve Portuguesa 35 Couve Portuguesa 36 Couve de Grelo 37 Couve de Grelo 38 Couve Branca Couve de Valhascos 39 40 Couve de Valhascos 41 Couve de Valhascos 42 Couve de Valhascos Couve Murciana 43 44 Couve Murciana 45 Couve Algarvia B. oleracea var. acephala : 46 Couve Galega Couve Galega 47 48 Couve Galega Couve Galega 49
Origin'
Code`
Loivos, Chaves, Pt Caneiro, Chaves, Pt Paradela, Chaves, Pt
ISA 10 ISA 12 ISA 19
Mirandela, Mirandela, Pt Mirandela, Mirandela, Pt Mirandela, Mirandela, Pt Safres, Alijo, Pt ?, seed retailer Apulia, Esposende, Pt Agucadoura, Povoa do Varzim, Pt Agucadoura, Povoa do Varzim, Pt Estela, Povoa do Varzim, Pt ?, seed retailer Arcozelo da Serra, Gouveia, Pt Belinho, Esposende, Pt Belinho, Esposende, Pt Mindelo, Vila do Conde, Pt Arcozelo da Serra, Gouveia, Pt Contencas de Baixo, Mangualde, Pt Fund6es, Mangualde, Pt Verdemilho, Aveiro, Pt Cordinha, Mealhada, Pt Bolho, Cantanhede, Pt Cantanhede, Cantanhede, Pt Castelo Viegas, Coimbra, Pt Eira Pedrinha, Condeixa, Pt Ribeira, Condeixa, Pt Arrocha, Condeixa, Pt Casconha, Condeixa, Pt Casconha, Condeixa, Pt Caxaria, Pombal, Pt Cabego da Azoia, Leiria, Pt Salemas, Loures, Pt Costa de Caparica, Almada, Pt Costa de Caparica, Almada, Pt A-dos-Caos, Loures, Pt Tojalinho, Loures, Pt Nordeste, S. Miguel, Azores, Pt Valhascos, Sardoal, Pt Valhascos, Sardoal, Pt Valhascos, Sardoal, Pt Abrantes, Abrantes, Pt Viana do Alentejo, Viana do Alentejo, Pt Viana do Alentejo, Viana do Alentejo, Pt Verdemilho, Aveiro, Pt
ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA ISA
444 453 2 120 600 454 333 125 124 506 83 130 129 178 84 91 500 205 318 330 494 145 291 284 265 271 272 249 143 134 190 191 61 55 198 36 35 20 502 62 73 207
Mairos, Chaves, Pt Contencas de Baixo, Mangualde, Pt Sete Fontes, Cantanhede, Pt Meirinhas de Cima, Pombal, Pt
ISA ISA ISA ISA
345 92 314 343
57 each year were studied using standard numerical taxonomic techniques (cf. Sneath & Sokal, 1973) .
formed based on the correlations among the char-
For a better understanding, the elementary unit to
es of the OTUs, and of the original characters were
be classified in each analysis was named OTU (=
also computed .
Operational Taxonomic Unit) . The data were analyzed based on the following basic data matrices : (1)
All computations were carried out using the NTSYS-pc (Numerical Taxonomy and Multivariate
matrix A (46 characters x 58 OTUs) on which the
Analysis Systems) package, version 1 .5 of computer
score for each accession (= OTU) was the mean character value for the two years ; (2) matrix B (92
programs (Rohlf, 1989) .
acters . Projections onto the first, two, and three ax-
char. x 58 OTUs) on which each accession is one OTU and the character scores for each year are considered separately; (3) matrix C (46 char . x 116
Results and discussion
OTU5) on which each accession on each year was
Landrace grouping and similarity
taken as a distinct OTU. The classification based on matrix A will represent the most standard classification of the coles under study, independently of
Phenograms based on correlation and distance coefficients among OTUs of the average results of
the interannual variation of the characters . Matric-
the two observation years (Matrix A) are presented
es B and C take this variation into account, using two different approaches .
in Figs . 3 and 4 . Their cophenetic correlation coefficients are r = 0 .7685 and r = 0 .8565, respectively. The
For all cases referred to above the characters
correlation phenogram (Fig. 3) suggests the exist-
were standardized before computation of the corre-
ence of eight groups A-H. The first five groups (A,
lation and average taxonomic distance coefficients among OTUs . The OTUs were clustered by the un-
B, C, D, E) are clustered in a large group including almost all the plants usually designated as Tronchu-
weighted pair group method using arithmetic aver-
da cabbages . Group F includes cabbages, group G
ages (UPGMA) and the results presented in the form of phenograms . The cophenetic coefficient for
miscellaneous coles, and group F Galega kales . The first two groups, A and B, contain the acces-
the phenograms was also computed as a measure of
sions of Tronchuda cabbages from Northern Portu-
the distortion of the method of clustering used . Also a principal components analysis (PCA) was per-
gal above the Douro River (Fig. 2) . Group A is
Table ] .
formed by Tronchuda cabbages from "Tras-os-
Continue
Accession number
Identification
Origin'
Code`
50 51 52 53
Couve Couve Couve Couve
Tojalinho, Loures, Pt Costa de Caparica, Almada, Pt Sardoal, Sardoal, Pt Alvito, Alvito, Pt
ISA ISA ISA ISA
57 187 28 66
Alfambras, Aljezur, Pt Carrapateira, Vila do Bispo, Pt ?, France ?,France
ISA ISA ISA ISA
225 232 471 484
Ferreiras, Albufeira, Pt
ISA 67
Galega Galega Galega Galega
B. oleracea var . capitata:
54 55 56 57
Couve Repolho do Algarve Couve Repolho do Algarve Cabbage Bacala Frisada Cabbage Coracao de Boi
B. oleracea var . sabauda
58 a
Couve Repolho-lombarda do Algarve
Botanical classification according to Williams & Hill (1986) . The Portuguese accessions were tentatively ascribed to the different taxa based on previous knowledge of their morphological characteristics . n Locality, County, Country ; Pt = Portugal; ? = unknown locality or county ISA = Instituto Superior de Agronomia, Technical University of Lisbon, Lisbon, Portugal
58 Montes" province (see Fig . 2) . In this group it is possible to distinguish two subgroups . Subgroup Al formed by Penca de Chaves (1, 2, 3) and subgroup
central Portugal; and subgroup C2, relatively heterogeneous, formed by Couve Calcuda (26, 27), Couve da Arrocha (28), Couve de Bolho (23) and
A2 including Penca de Mirandela (6, 5), Penca de Safres (7), Penca de Mirandela Pao de Acucar (4),
Couve da Cordinha (22), all from the coastal region
and a seed-retailers selection originally named Pen-
Group D is constituted by Couve Portuguesa (33-35) and other similar local selected landraces,
ca Espanhola(8) . Group B includes Tronchuda cabbages Penca da Povoa and Coivao (10-17) originated from "Min-
of central Portugal.
such as Couve de Castelo Viegas (25), and Couve de
ho", the Northern coastal province of Portugal (Fig .
Corte (21, 29, 30) . Group E contains Tronchuda cabbages Couve
2) .
Murciana (43,44) and Couve de Valhascos (40-41) Group C includes nine accessions collected in
central Portugal . In group C two sub-groups can be
from Southern inland Portugal, plus Couve Tronchuda Branca de Cantanhede (24) .
distinguished : subgroup Cl constituted by Couve
Group F, well separated from the previous five
Gloria de Portugal (18-20), from the highlands of
Tronchuda cabbage groups, is constituted by cab-
Table 2. List of the 46 morphological characters used in the characterization of Portuguese coles A.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
22 23
Observations immediately before normal harvest (commercial maturity)
24
Emission of secondary stems (0 = absent ; 1 = low ; 2 = intermediate ; 3 = high)
Fresh weight of whole plant excluding the roots (g) Dry weight of plant stem (g) Dry weight of plant leaves (g) Plant height (cm) Plant diameter (cm) Total number of developed leaves (number of leaves and leaf scars) Angle of leaf petiole with horizontal (0 = erect ; 1 = open ; 2 = semiprostrate ; 3 = prostrate) Length of the largest leaf (cm) Blade width of the largest leave (cm) Petiole length (cm) Petiole width at the base line of the blade (mm) Petiole thickness at the base (mm) Petiole width at the base (mm) Number of vascular veins at the petiole base Ramification of secondary veins (0 = not palmate ; l = palmate) Ondulation on the largest leaf (0 = weak ; 1 = medium; 2 = strong) Leaf tip attitude (0 = highly curving upwards ; l = curving upward ; 2 = straight; 3 = drooping) Leaf blade thickness (0 = thin ; 1 = thick) Leaf blade bloom (0 = low ; 1 = intermediate; 2 = high, glaucous) Frequency of plants with supplementary segments in the upper level of midrib (%) Heading (rosette) habit (0 = leaves curled outwards ; 1 = leaves curled inwards ; 3 = leaves slight overlapping ; 4 = leaves strong overlapping) Stem length (cm) Stem maximum width (cm)
B. 25 26
Observations at flowering, silique maturity and seeds
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 C. 43 44 45 46
Length of floral stem (cm) Branching degree of floral stem (0 = primary ; 0.5 = primary-secondary ; 1 = secondary) Average length of the first three internodes of floral stem (mm) Average length of buds (mm) Number of weeks to reach 30% of flowering plants Frequency of plants with white petals (%) Petal length (mm) Petal width (mm) Angle of silique pedicel (0 < 60°;1 = 60-90°; 2 > 90°) Length of silique pedicel (mm) Silique length (mm) Silique width (mm) Silique beak length (mm) Silique beak width (mm) Silique surface outline (0 = smooth ; 1 = undulating ; 2 = very undulating, constricted between seeds) Average number of seeds per silique Weight of 1000 seeds (g) Percentage of plants with estipules at pedicel base Observations at seedling stage
Foliar area of cotyledons (0 = low ; 1 = intermediate; 2 = high; 3= very high) Percentage of seedlings with pubescence on the first two leaves Blade leaf colour at five leaf stage (0 = yellow green ; 1 = light green ; 2 = green ; 3 = dark green) Anthocyanin pigmentation at five leaf stage (0 = absent; 1 = low ; 2 = intermediate ; 3 = high ; 4 = very high)
59 CORRELATION 0.30
0 .60
0.90 4
C
0 .00 -0 .30 1 1
1 2 3 6 8 5 7 4 10 12 13 9 14 11 16 15 17 18 19 20 27 28 26 23 22 25 29 30 21 34 33 35 24 44 43 41 39 42 40 . 58 E: 54 ]F1 55
D
E
F
57 :1 F2
31 38 32 45 36 52 47 49 53 46 50 51 48
G
H
Phenogram based on correlation coefficients among OTUs using matrix A of the average results of the two observation years (correlation coefficient, r = 0 .7685) . The letters A to H refer to the accession groups defined in the text . The numbers refer to accessions listed in Table 1 . Fig. 3 .
bages (B. oleracea var. capitata) and includes two subgroups : subgroup Fl with Couve Repolho do Algarve (54,55) and Couve Repolho-lombarda do Algarve (58) ; and subgroup F2 with the imported common cabbages, Couve Bacala Frisada (56) and Couve Coracao de Boi (57) . Group G is very heterogeneous and includes miscellaneous Tronchuda cabbages from central Portugal : Couve de Corte (31), Couve Branca (38), Couve Silveirinha (32), Couve Algarvia (45) and Couve Grelo (36, 37) . Finally, group H, well isolated, contains all Gale-
ga kales (Couves Galegas) from different Portuguese geographic origins (48-52) . The distance phenogram (Fig . 4) recovers the majority of the groups refered to above for the correlation phenogram (Fig . 3) . The main differences reside in the fragmentation of groups F and G . The cabbage Couve Coracao de Boi (57) in group F is now separated from the other common cabbages . The coles of the heterogenous group G are now dispersed into the large group of Tronchuda cabbages close to group C, with the exception of Couve Al-
60 DI S TA N C E 2 .40
1 .80
1 .20
0 .60 0 .00 1
H
1 32 7 5 6 8 10 12 13 14 9 11 16 15 17 25 29 30 2, 34 33 35 24 41 42 40 44 39 1,3 37 36 38 18 19 20 26 23 22 32 31 27 28 58 54 55 56 52 47 48 50 51 49 53 46 45 57
A1 A A2
B
D
E
~G *
F*
H
F2
G* F*
Fig. 4. Phenogram baased on distance coefficients among OTUs using matrix A of the average results of the two observation years (r =
0 .8565) . The numbers refer to accessions listed in Table 1 . The letters A to H refer to the accession groups defined in the text . The groups signalized with an asterisk have suffered modifications relatively to the groups existing in the correlation phenogram (Fig . 3) .
garvia, which is close to the group H of Galega
resemblance of coles based mainly on their morph-
kales . The fragmentation observed in Groups F and G
ological similarities independently of their size,
(Fig . 3 and 4) can be justified by the different philosophy expressed by the coefficients used to quantify the similarity among the accessions in the two phenograms . The phenogram based on the correlation coefficients clusters OTUs structurally equal independently of their size, while in the phenogram
while the distance coefficients express the resemblance considering also cole size . For instance, Couve Corarao de Boi (57) clusters in the correlation phenogram with the other cabbages, since its structure is very similar to them, even though it is smaller . In the same way, the coles of Group G ap-
based on distance coefficients the size of the OTUs has a relevant role . Applying this to the observed
pear in the correlation phenogram (Fig. 3) close to the Galega kales (Couves Galegas), because they have a kale-like structure . Couve Algarvia (45)
cole plants, the correlation coefficient expresses the
holds its position close to the kales in the distance
61
CORRELATION -0.30
0.00
0.30
1
0.60
0.90
1
23 5 s7
Al
A A2
4 10 9 12 13 14 11 15 16 17 25 29 30 21 34 33 35 24 37 36 44 43 41 42 40 39
C
[~
B
5 Fl s7 ] F2 16 19 20 27 26 26 23 22 31 38 32 45 52 47 49 53 46 50 51 4B
F J
]Cl C
IG H
Phenogram based on correlation coefficients among OTUs using data matrix B on which each accession is one OTU and the character scores for each year are considered separately (r = 0 .7747) . The numbers refer to accessions listed in Table 1 . The letters A to H refer to the accession groups defined in the text . The groups signalized with an asterisk have suffered modifications relatively to the groups existing in the correlation phenogram (Fig . 3) . Fig. 5.
phenogram, perhaps because its high value for the variable stem weight/total weight, owing to the ex-
via (45) that clusters with the Galega kales as men-
istence of secondary shoots, and the small roset-leaf overlapping inducing a kale-like structure .
The five landrace groups of Tronchuda cabbage (A, B, C, D and E) obtained in the present numer-
The distance phenogram (Fig . 4) recovers basi-
ical analysis correspond to the five ecotypes of Portuguese Tronchuda cabbage presented by Cerca
cally the three major groups in which Portuguese coles are traditionally classified : (i) Tronchuda cabbages (1-28), (ii) Galega kales (46-52), and (iii)
tioned before.
(1946) : Penca de Chaves, Penca da POvoa, Gloria de Portugal, Couve Portuguesa and Couve Murciana .
common cabbages (56-58) . The exceptions to this
The numerical taxonomy and the larger universe of
classification are the cabbage Couve Coracao de Boi (57) which appears isolated, and Couve Algar-
sampling used in the present study allowed a deeper look into each of the defined groups . This thorough
62 DISTANCE 2 .40 1 .80 1 .20 I I
0. 60
0.00 1 2 A1 3 A a 7 A2 4 5 10 12 13 14 9 B 11 16 15 17 25 29 30 21 34 33 35 24 41 42 39 40 44 43 37 G * 36 19 19 20 26 23 22 27 28 31 32 38 sa 1F1J F* 55 56 -F2 52 47 49 53 H 48 50 51 71C 46 57-F2_G F~`
Fig. 6. Phenogram based on distance coefficients among OTUs using data matrix B on which each accession is one OTU and the character scores for each year are considered separately (r = 0 .8662) . The numbers refer to accessions listed in Table 1 . The letters A to H refer to the accession groups defined in the text . The groups signalized with an asterisk have suffered modifications relatively to the groups existing in the correlation phenogram (Fig . 3). analysis questions some of Cerca (1946) comments . For instance, Penca de Chaves and Penca de Mirandela are not the same morphotype as suggested by Cerca (1946) . The correlation phenogram (Fig . 3) shows the existence of two subgroups in group A of "Tras-os-Montes" Tronchuda cabbages : Penca de Chaves, plus Penca de Mirandela, Penca de Safres, and Penca Espanhola . There are also subgroups in group B, as Penca da POvoa and Coivao, or in group E, as Couve Murciana and Couve de Valhascos not mentioned by Cerca (1946) .
The morphological diversity existing within each of the above described Tronchuda cabbage groups suggests that they should be regarded as landrace groups and not always as individually defined landraces . Despite the morphological diversity, landraces from the same region have sufficient characteristics in common to be considered a landrace group. This justifies the recognition of five Tronchuda cabbage landrace groups, morphologicaly distinct and representative of the major growing regions : (A) "Couves de Tras-os-Montes" ; (B)
63 CORRELATION -0 .40 1
-0.05
0.30
0.65
1 .00 2 a S 6 1 a ' . 3. 2 6a 6a 7a Sa 4• 12 3
14 9 ,Oa 111 7 16 1s 124 13 . 144 114 17 18 a15a 19 IBM 1 20 20 a 2 2 28 26 27 23 2 25
A
B
C1 C* C 2
"~
2 JO 33 2 ]4 35 44 39 42 40 u 25 . 29a~ a 33 a 21 a »' J5 4 J2 J1 . J7 2a J ' ' 44 a ~ 4 J7a 40 . 8 5 4 54 55 554 56 ' 57 a 57 . 5,6 36 J' 47 52 53 50 46 46 52 a 47 494 53 50 49 4 328 38 45 a
23 .22-
D* J , J
E*
F F2
H*
G 1k JC21
CH*
Fig. 7. Phenogram based on correlation coefficients among OTUs using data matrix Con which each accession on each year was taken as a distinct OTU (r = 0 .6837) . Numbers refer to accessions listed in Table 1 observed during the first year . Numbers followed by an `a' refer to accessions listed in Table 1 observed during the second year . The letters A to H refer to the accession groups defined in the text . The groups signalized with an asterisk have suffered modifications relatively to the groups existing in the correlation phenogram (Fig . 3) . "Couves do Minho" ; (C) "Couves from Central Portugal"; (D) "Couve Portuguesa" ; (E) "Couves from Southern inland Portugal" . The groups obtained using morphological characters differ from those obtained using nuclear RFLPs (Dias et a1.,1992) . The aggregation of soles based on RFLPs was related to their geographic origin despite their remarkable morphological differences e.g. RFLPs have clustered Galega kales and Tronchuda cabbages from the same area . In the morphological approach Tronchuda cabbages and Galega kales appear well separated . Morphologi-
tent than others . For example, those from northern inland and northern coastal Portugal always keep their individuality through all morphological data analysis, whilst accessions from central coastal regions change their relative positions easily . It seems that the geographic isolation had a great role in this fact because, in contrast to northern Portugal, in central coastal Portugal there are no important physical barriers and the exchange of seeds and seedlings is quite frequent owing to a good transportation network . Common cabbages clustered independently
cally distinct soles are always ascribed to different groups .
from Tronchuda cabbages and Galega kales in the nuclear RFLPs (Digs et 41., 1992) and in the morph-
Morphologically, there are groups more consis-
ological approaches . Both approaches also agree on
64 2 .00
1 .60
DISTANCE 1 .20
0.80
0.40 - j --2 4 7 B 6 Ja S 6
I
A*
a 6a 5 a 7a 4 i 10 C 1 4 12 9 14 i1 13 16 17 1a
lB i1A *
1oa
C
9a 13 a 12 1 1J 14a 17a 16a 13a 25 2
30 21
J
21 34 .
D
J4
J 1--/
1
_ 32.5a 338 24 JS a ia24 a 424
4J
E
4~4 a 43 a 42 i 44 39 2 40
L I
J7a38a JA 35 ° 1 9 1s taa? 9a 20 26 22 26 2J a 22 a
J1a 1.7 . z 7a 258 54
55
5S. 54a
,
10 _
]C1 C* ]C2 '0 * ]c2] C*
I F1 I
6a37
3
F
*
G*
52 .9
50 46 4B 5J 46 a SJ a4507 i a ~a49 a 45 J2 a S7-a 37 a
H
m
G* F*
Fig. 8. Phenogram based on distance coefficients among OTUs using data matrix C on which each accession on each year was taken as a distinct OTU (r = 0 .7868) . Numbers refer to accessions listed in Table 1 observed during the first year. Numbers followed by an `a' refer to accessions listed in Table 1 observed during the second year. The letters A to H refer to the accession groups defined in the text . The groups signalized with an asterisk have suffered modifications relatively to the groups existing in the correlation phenogram (Fig . 3) .
the definition of two subgroups in the distinct group
tinned Couve do Algarve as a "variety of foreign
of cabbages: one formed by the common and savoy
origin grown in the Algarve province" .
Algarve cabbages, and another including the imported cabbages . In the RFLPs analysis it was concluded that Algarve cabbages appeared to be genetically closer to cabbages Couve Coracao de Boi and Couve Bacala Frisada than these two cabbages are to the Brunswick cabbage which is not grown in Portugal . In the morphological approach Algarve cabbages shown high resemblance to Couve Bacala Frisada . These facts may suggest that Algarve cabbages were originated from plants of Couve Bacala introduced in Portugal which have evolved and were selected in Algarve province . This hypothesis is in accordance with Anonym (1896) that has men-
Interannual variation
Phenograms based on correlation and distance coefficients among OTUs using data matrix B, on which each accession is one OTU and the character scores for each year are treated as separate variables, are shown in Fig . 5 and 6 . The clustering pattern in the correlation phenogram (Fig. 5, matrix B) is similar to that obtained considering the two years average values for each character (Fig . 3, matrix A) . Although, some small
65 differences exist : Couve Grelo (36, 37) was moved
the phenograms based on different sets of charac-
from the heterogeneous group G and joined Couve
ters (matrices A, B, and C) the principal component analyses (PCA) was only carried out for matrix A .
de Valhascos and Couve Murciana in group E ; and Tronchuda cabbages from central Portugal in group C were separated from the other Tronchuda cabbages to cluster with group H and part of group G . A similar comparative analysis between the phenograms based on the distance coefficients among OTUs using data matrix A (Fig . 4) and using data
Fig. 9a and 9b shows the projections of the 58 cole accessions onto the planes defined by the components 1-2 and 1-3 . Fig. 9c and 9d shows the projections of the initial characters onto the same plans . The percentage of variation explained by components 1, 2, and 3 is 23 .98%,13 .06%, and 12.53%, re-
matrix B (Fig . 6) shows that the two phenograms are quite similar . There are however small alter-
spectively.
ations in the heterogeneous group G where Couve
kales from Tronchuda cabbages plus common cab-
Branca (38) is now clustered with one accession of
bages . The characters that have contributed more to that separation are (Fig . 9c) : 22, 4, 25, 29, 2,10, 21,
Couve de Corte (31) and with Couve Silveirinha (32) forming a subgroup relatively isolated . Fig . 7 and 8 show the phenograms based on correlation and distance coefficients among OTUs using data matrix C on which each accession on each year
Fig. 9a shows that component 1 separates Galega
11, 23, 7,1, 9, and 13 . This separation reflects important morphological differences among Portuguese coles . It points out that Galega kales are characterized by their greater height owing to longer stem
was taken as a distinct OTU. In general the same
(22) and floral stem (25), and by greater stem dry
groups previously revealed (Fig . 3 to 6) are reco-
weight (2) . Fig. 9 also confirms that Galega kales have longer petioles (10) and require longer periods
vered, although the groups appear now subdivided according to each year. For example, inside groups A, B, D, F, H, and subgroup Cl in the correlation phenogram (Fig. 7) it is distinguishable a cluster
of time before flowering (29) than Tronchuda cabbages . Tronchuda and common cabbages are characterized by : more overlapping of rosette leaves
with the accessions grown in 1989/90 and another
(21) leading to the formation of a head of variable
cluster with the same accessions grown in 1990/91 . The same clustering pattern appears in the distance phenogram (Fig. 8) . The only exception to this rule
compactness; wider petioles (11, 13) ; larger stem diameter at commercial maturation stage (23) ; more prostrate insertion of leaves (7) ; bigger weight
is group E (Couve de Valhascos and Couve Murcia-
of whole plant excluding the roots (1) due essential-
na ) which in the correlation phenogram (Fig . 7) was divided according to the years and in the distance
ly to the higher number of leaves (6), and the wider leaf blades (9) .
phenogram (Fig . 8) appears as a single group . Based on these results it is possible to conclude that the interannual variation observed for the dif-
Characters contributing more in component 2 (Fig. 9c) are 5, 8, 3, 1, and 9 . Component 2 separates Tronchuda and common cabbages according to
ferent morphological characters did not greatly af-
their spread . Thus Couve Calcuda (26, 27), Couve
fect the overall clustering patterns of the studied accessions, so that the same classification of the vari-
de Corte (31), and Algarve common cabbage and Algarve savoy cabbage (54, 55, 58), among others,
ous cole landraces obtained . Other researchers
have a large spread (5) with long and wide leaves (8,
have also arrived to similar conclusions about the influence of interannual variation on the stability of
9), that conferred them high dry weight of the leaves (3) . In opposition the accessions Couve Coracao de
morphological classifications (Lima, 1965 ; Crovello, 1968 ; Ferraz & Lima, 1992) .
Boi (57), Penca da POvoa (9) and Couve Grelo (36, 37) have low spread, short and narrow leaves, and low leaf dry weight . The remaining coles are in an intermediate position .
Character relative usefulness Owing to the similar results previously verified on
Characters that have contributed more in component 3 (Fig . 9d) are 30, 27,14, 6, and 20 . Component 3 allows the separation of common cabbages
66
a
GROUPS :
26 ∎ 310
0.5-
H (GALEGA KALES)
∎ 23 ∎ 22
32 0
19w
A ∎ • •
56
-B -C
-D -E * -F 0 -G • -H
043 ∎ 18
20 ∎
48 O\
• -A
27 54 ∎ 5B* 55
**1
, ,n ∎ 28
°
15A i
0.0
•p0
0
• A0 38
2 47
51 0
0
50 /
0 45
A A°° 08 0 °
0
o° 5,4A12 360
-0.5
10
370 \
46
A 9
/ 57
-1 .6
-1 .0
-0 .5
,
0 .5
0.0
1 .0
1.6
IbI
GROUPS :
F /
57
A - B • - C • - D • - E • - F • - G • - H
~54
1 .0-
15 H (GALEGA KALES)
0.5
3
\
47 / 0.0
• - A
I
(CABBAGES)
460 0
(049
500 \
S30
45 0
G* / /32
48/
0
/ /
*55 /
i
0 0) 520 51
~
370 360
•
•
380
19
I
∎ ∎
\ 31 0 ∎ ∎
•
°
•
`•
A
•
°
\
CO° \
1
O O A2O O°
A •° ∎ AAO ∎~ ∎
Fig. 9. Projection of the 58 coles (a, b) and of the 46 char-
/
acters (c, d) onto the plans defined by the principal components 1-2 (a, c) and 1-3 (b, d) .
-0 .5
Numbers 1 to 58 (a, b) refer to accessions listed in Table 1 .
A, B, C, D, E, G 'k (TRONCHUDA CABBAGES) -1 .0 -1 .6
, -1 .0
-0.5
1
0 .0
0 .5
Numbers 1 to 46 (c, d) refer to characters listed in Table 2 . 1 .0
Letters A to H refer to groups defined in the text.
67 1 .0-
0.5-
0.0
2 44
-0.5-
-1 .0 -1 .6
, -1 .0
-0.5
1
0 .0
1 1.0
0.5
1 .6
1 .0
19
0.5 21
3 0.0
Fig. 9 (cont.) . Projection of the 58 coles (a, b) and of the 46 characters (c, d) onto the plans defined by the principal
11
-0 .5
components 1-2 (a, c) and 1-3 (b, d) . Numbers 1 to 58 (a, b) refer to accessions listed in Ta-
12
-1 .0 -1 .6
1 -1 .0
ble 1 . Numbers 1 to 46 (c, d) refer to characters listed in Ta-0 .5
0.0
0 .5
1 .0
ble 2 . Letters A to H refer to groups defined in the text.
68 from the Tronchuda cabbages and Galega kales .
Nacional de Investigagao Cientifica e Tecnologica),
Common cabbages are characterized by having a higher number of leaves and leaf scars (6), and yel-
Lisbon, Portugal, under project no . 87293/AGR.
low petals (30) in opposition to the Tronchuda cabbages and Galega kales that have, in general, white petals (30) . Tronchuda cabbages and Galega kales also have a higher average length of the first three internodes of floral stem (27) and a higher number of veins at the petiole base (14) than common cabbages . The principal component analyses has confirmed the cole grouping previously shown in the various phenograms : Tronchuda cabbages, Galega kales, and common cabbages . A PCA analysis only with Tronchuda cabbages (not presented here) also confirmed the landrace groups A to E . However, a major conclusion of PCA is the study of the variation of cole accessions and the detection of particular sets of characters that characterize some subregions of the multidimentional space which are relevant from an horticultural point of view. This makes possible the selection of coles that satisfy specific sets of characteristics . Therefore, PCA gives the breeders some insite about the groups where certain characteristics are more valuable allowing them to move faster on conducting specific breeding programmes .
Acknowledgements Partial funding was provided by the National Board for Scientific and Technological Research (Junta
References Anonym, 1896 . Guia de Horticultura Pratica . Casa Frederico Daupias . Lisboa . 156 p. Cerca, M .C., 1946 . Subsfdios para a caracterizacao e identificacao de algumas formas cultivadas da especie Brassica oleracea L . nacionais ou de ha muito cultivadas em Portugal . Relatorio final do Curso de Engenheiro Agronomo . Universidade Tecnica de Lisboa . Lisboa. 156 p . Crovello, T.J ., 1968 . The effect of alteration of technique at two stages in a numerical taxonomic study. Univ. Kansas Sci . Bull. 47,761-768 Dias, J .S . ; M .B. Lima ; K .M. Song; A .A. Monteiro ; PW. Williams & T.C . Osborn, 1992 . Molecular taxonomy of Portuguese tronchuda cabbage and kale landraces using nuclear RFLPs . Euphytica, 58 : 221-229 . Ferraz, J .F.P. & M .B. Lima, 1982 . Utilizacao de metodos de taxonomia numerica no estudo das relacoes feneticas de isolamentosos de Colletotrichum e de Gloeosporium . Garcia de Orta, Ser . Est. Agron ., Lisboa, 9(1-2) :197-212 . IBPGR, 1989 . Descriptors for Brassica and Raphanus . International Board for Plant Genetic Resources . Rome . 51 pp. Miguel, M .C ., 1957. Varieties of "tronchuda" or veined cabbage . Proc. Int. Seed Test . Ass., 22(l) :1-14. Rohlf, EJ .,1989 . NTSYS-pc. Numerical Taxonomy and Multivariate Analysis System . Version 1 .5 . Exeter Publishing, Ltd . . Setauket, New York . Lima, M .B., 1965 . Studies on the species of the genus Xiphinema and other nematodes. Ph. D. thesis, University of London, 165 PP. Sneath, P.H .A . & R .R . Sokal, 1973. Numerical Taxonomy. The Principles and Practice of Numerical Classification . W.F. Freeman & C . . San Francisco . 573 p. Williams, PH . & C .B . Hill, 1986 . Rapid-cycling populations of Brassica. Science 232:1385-1389
