João Silva Dias

Effect of activated charcoal on Brassica oleracea microspore culture embryogenesis

The effect of the addition of a 0.1 ml drop of activated charcoal (AC) on microspore culture embryogenesis was studied in nine morphotypes of Brassica oleracea. Embryo yields were significantly increased in all of the morphotypes by the addition of the 0.1 ml drop of AC to the microspore culture media. The magnitude of the response to the addition of AC varied with the different plants and morphotypes. The addition of AC never produced a detrimental effect. A qualitative improvement of the subsequent development of embryos to plants was also observed with the addition of AC. Data suggest that the addition of AC to microspore culture media promoted embryo production in different B. oleracea morphotypes.The effect of the addition of a 0.1 ml drop of activated charcoal (AC) on microspore culture embryogenesis was studied in nine morphotypes of Brassica oleracea. Embryo yields were significantly increased in all of the morphotypes by the addition of the 0.1 ml drop of AC to the microspore culture media. The magnitude of the response to the addition of AC varied with the different plants and morphotypes. The addition of AC never produced a detrimental effect. A qualitative improvement of the subsequent development of embryos to plants was also observed with the addition of AC. Data suggest that the addition of AC to microspore culture media promoted embryo production in different B. oleracea morphotypes.

Common names of commercially cultivated vegetables of the world in 15 languages

The cultivated vegetable crops of the world are listed by family and Latin binomial, followed by the common name(s) in English, Arabic, Chinese (Mandarin), Danish, Dutch, French, German, Hindi, Italian, Japanese, Malay, Portuguese, Russian, Spanish, and Tagalog. The edible portion of the plant utilized for food and the general method of preparation were reviewed and listed.RésuméApresentase uma lista das culturas olerícolas cultivadas no Mundo organizadas por famílias e os seus nomes latinos seguidos dos respectivos nomes vulgares em Inglês, Árabe, Chinês (Mandarin), Dinamarquês, Holandês, Francês, Alemão, Hindu, Italiano, Japonês, Malaio, Português, Russo, Espanhol e Tagalogue. Para cada uma das culturas refere-se qual a sua parte comestível e o seu modo de preparação na alimentação.

Numerical taxonomy of Portuguese Tronchuda cabbage and Galega kale landraces using morphological characters

SummaryA 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 Trás-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.

Effect of incubation temperature regimes and culture medium on broccoli microspore culture embryogenesis

Conditions for reliable induction of embryogenesis from isolated microspores were studied in ten genotypes of broccoli. Embryo yields were significantly increased in almost all of the broccoli genotypes by the incubation at 32.5 °C for 1 day, than when the standard incubation at 30 °C for 2 days was used. Treatments of 48 hours at 32.5 °C produced less than optimal results suggesting that broccoli microspores are more sensitive to high temperatures than those of B. napus. The use of the 1/2 NLN-13 medium yielded greater number of embryos than the standard NLN-13. The magnitude of the response to the redution of the concentration of major salts by half in the NLN medium varied with the different genotypes. High embryogenic broccoli cultivars, such as ‘Shogun’, ‘SDB9’, and ‘Green Valiant’, presented a better response to the reduction of the concentration of major salts by half in NLN-13. Reduction never produced a detrimental effect on embryo yield and seems not to have any effect in the subsequent development of embryos in plants.Conditions for reliable induction of embryogenesis from isolated microspores were studied in ten genotypes of broccoli. Embryo yields were significantly increased in almost all of the broccoli genotypes by the incubation at 32.5 °C for 1 day, than when the standard incubation at 30 °C for 2 days was used. Treatments of 48 hours at 32.5 °C produced less than optimal results suggesting that broccoli microspores are more sensitive to high temperatures than those of B. napus. The use of the 1/2 NLN-13 medium yielded greater number of embryos than the standard NLN-13. The magnitude of the response to the redution of the concentration of major salts by half in the NLN medium varied with the different genotypes. High embryogenic broccoli cultivars, such as ‘Shogun’, ‘SDB9’, and ‘Green Valiant’, presented a better response to the reduction of the concentration of major salts by half in NLN-13. Reduction never produced a detrimental effect on embryo yield and seems not to have any effect in the subsequent development of embryos in plants.

Effect of silver nitrate on anther culture embryo production of different Brassica oleracea morphotypes

The effect of three concentrations of silver nitrate on anther culture embryo production was studied in 27 morphotypes of Brassica oleracea. Embryo yields were significantly increased in the majority of the morphotypes by the addition of silver nitrate to the media. Embryo yields were not increased in only a few of the almost nonembryogenic accessions. The magnitude of the response to silver nitrate varied with the different morphotypes. In general, the best results were obtained with the addition of 10 mg l ˇ1 AgNO3. Without the addition of silver nitrate no embryos would have been obtained in some of the nonembryogenic morphotypes. Data suggests that silver nitrate addition to anther culture media promoted embryo production in different B. oleracea morphotypes. # 1999 Elsevier Science B.V. All rights reserved.

Screening Portuguese cole landraces for resistance to seven indigenous downy mildew isolates

Abstract Twenty-nine Brassica oleracea accessions, including Portuguese cole landraces, were screened for resistance to crucifer downy mildew using seven Portuguese isolates of Peronospora parasitica. Seven-day-old seedlings were inoculated on the cotyledons with two 10 μl droplets of a water suspension containing 5 × 105 conidiospores ml−1. Host-pathogen interaction phenotype (IP) was evaluated 7 days after inoculation using an increasing susceptibility (1–9) scale. The screening revealed high variable reaction for downy mildew resistance within Portuguese cole landraces. Some accessions were very susceptible with most of the plants scoring in IP classes 7 and 9, but most of the accessions showed high variability in interaction phenotype with plants scoring in all IP classes. Four accessions belonging to landraces ‘Couve Algarvia’, ‘Couve Murciana’ and ‘Couve Coracao de Boi’ expressed high resistance to all downy mildew isolates, with over 42% of seedlings in the non-sporulating IP class 1. Downy mildew isolates Pp504 (Batalha), Pp503 (Condeixa), and Pp507 (Faro) showed slightly higher aggressiveness than isolates Pp505 (Loures), Pp502 (Vila Real), Pp506 (Odemira), and Pp501 (Povoa). There was no significant interactions between accession and downy mildew isolate, which shows that the geographic origin of the host and pathogen had no influence on the interaction phenotype. This study confirms the high potential of Portuguese cole landraces as sources of resistance to downy mildew and has identified accessions with a high valuable resistance.

Evaluation of a core collection of Brassica oleracea accessions for resistance to white rust of crucifers (Albugo candida) at the cotyledon stage

The identification of seedling resistance to white rust of crucifers was performed in a screening of a B. oleracea core collection with 400 accessions representing the genetic and geographic diversity of the species. Fifty seedlings per accession were tested against the Portuguese isolate Ac502 using the methodology and evaluation procedures developed by and . The percentage of resistant seedlings (%R) and the conventional rating criteria of the mean Disease Index (DI) based on the two different evaluation procedures of disease expression used, were compared and adopted as the criteria to rank the accessions for their interest as sources of resistance. A great variability of reactions was found between and within accessions of the core collection, ranging from complete resistance to full susceptibility. Sources of resistance were found namely among the cauliflowers, broccoli and tronchuda cabbages gene pools. Forty-seven accessions presented at least 20% of resistant seedlings. Nine accessions (the kales INRA18 and INRA62, the cauliflowers HRI4856, HRI4866 and HRI5424, the loose-head cabbage HRI11555, the savoy cabbage BRA848, the black broccoli HRI6318 and the Portuguese tronchuda cabbage ISA207) presented 50–78% of resistant seedlings and so they should be considered as potential and useful sources for direct use in breeding programs for white rust resistance. Fourteen inbred lines, representing the full range of disease expression, derived from resistant accessions of the core collection were also tested for resistance to other two Portuguese isolates (Ac503 and Ac504) and to a UK isolate. The results provided no evidence of differential reaction to the A. candida isolates tested.

The Portuguese tronchuda cabbage and galega kale landraces: A historical review

SummaryPortuguese coles, tronchuda cabbage and galega kale landraces, are a unique group of vegetables very important for Portuguese horticulture owing to their excellent adaptation to prevalecent climatic conditions and good integration in the traditional small farming cropping systems. Reports on these coles are scarce and scattered. A bibliography review is presented on some general aspects of Portuguese cole landraces such as botany, folknames, foreign synonymy, origin, history, and worldwide spreading. In addition to such available information, other data has been gathered from growers in door-to-door enquiries during a germplasm collecting of Portuguese coles. Recent research on the taxonomy of Portuguese coles has been summarized.

Genetic diversity and taxonomy of Portuguese Tronchuda cabbage and Galega kale landraces using isozyme analysis

SummaryIsozyme analysis was used to study the genetic variation and the genetic relationships of a collection of 48 Brassica spp. including 31 Portuguese coles (Brassica oleracea L.) accessions representative of the different landraces cultivated in Portugal. Other brassicas included in this experiment were Jersey kale, kailaan, common cabbages, broccolis, cauliflower, nine-chromosome wild brassica and turnip. Nine enzymes used in the starch gel electrophoresis included: PGM, PGI, AAT, LAP, TPI, FBP, SOD, IDH and GR. Twenty-one putative loci were revealed, with 3 showing invariance and the other 18 contained 50 alleles. The allelic frequencies at these loci represented by 40 plants per accession were used to calculate the following estimators of genetic variation: % of polymorphic loci, average number of alleles per polymorphic loci, average number of alleles per locus, and index of heterozygosity. The genetic relationships were evaluated considering Nei (1978) and Rogers (1972) genetic distances between each pair of accessions whose matrices were hierarchically clustered by the UPGMA method. The accessions were also studied using the principal coordinate analysis.Portuguese Tronchuda cabbages and Galega kales have shown high genetic diversity in comparison with the other accessions. This indicates their potential variation for use in breeding programs. The UPGMA results show that the 48 accessions, with the exception of B. insularis, B. cretica, and turnip, can be clustered into 6 groups: (a) Portuguese Tronchuda cabbages, Galega kales and Algarve cabbages; (b) common cabbages and kales; (c) Couve Poda do Algarve and broccoli; (d) Algarve cabbage and common cabbages; (e) kailaan; (f) broccoli and cauliflower. The groupings obtained by the isozyme analysis are difficult to interpret considering the origin of the Brassica spp. and the morphological resemblance among the accessions.

Taxonomy of Portuguese Tronchuda cabbage and Galega kale landraces using morphological characters, nuclear RFLPs, and isozyme analysis: A review

SummaryMorphological characters, nuclear RFLPs, and isozyme analysis were used to study the similarity between 32 Portuguese Tronchuda cabbage and Galega kale landraces, and some cabbage cultivars traditionally grown in Portugal. Forty-six morphological characters observed in two consecutive years, RFLP data from 55 nuclear probes, detecting 291 polymorphic nuclear DNA restriction fragments, and allelic frequencies in 21 putative loci, generated by nine isozymes, were analyzed by the unweighted pair group method, using arithmetic averages (UPGMA), in order to present the results in the form of a phenogram. The three methods resulted in different clustering patterns of the 32 cole accessions. Morphological characters gave consistent clustering according to the traditional landrace definition and denomination, producing clear separation between Tronchuda cabbages and Galega kales. RFLPs were unable to separate Tronchuda cabbages from Galega kales and defined five landrace groups corresponding to their geographic origins rather than to their morphological similarities. Isozymes showed poor accession discrimination and an intermediate clustering pattern with some accessions being clustered according to their geographic origins and others according to their morphological similarities. Portuguese Tronchuda cabbages and Galega kales constitute a distinct and relatively homogenous group within Brassica oleracea, sharing the same genetic background. It is concluded that Portuguese coles have evolved independently from a common ancestor to the present cultivated forms. Portugal should be considered as an important region of domestication of specialized leafy coles.