RESUMO Variedades locais de milho doce (Zea mays L.) representam importante fonte de genes para programas de melhoramento, especialmente em modelos de pesquisa participativa. Avaliou-se o desempenho agronômico de sete variedades locais de milho doce (2255A, 2029A, 2276A, 2514A, 3000A, 741B e 319A) portadoras do gene sugary1 na condição homozigótica e duas testemunhas, em quatro ambientes [Anchieta (altitudes: 422 e 717 m), Guaraciaba (altitude: 624 m) e Florianópolis (altitude: 5 m)], no estado de Santa Catarina. As variedades 3000A e 319A apresentaram bom desempenho nas diferentes altitudes para comprimento de espiga e de grão e rendimento de espiga. Em altitudes intermediárias (422 e 624 m), as médias de rendimento de espiga sem palha (grão leitoso) destas variedades ficaram próximas a 12,5 t ha-1 (3000A) e 10,0 t ha-1 (319A). As variedades 2029A, 741B, 2514A, 2276A e 2255A destacaram-se pelo comprimento e diâmetro da espiga, número de fileiras da espiga e comprimento do grão. O melhor desempenho das variedades locais de milho doce foi observado em sua região de origem, especialmente nas altitudes entre 400 e 650 m. Essas variedades são adaptadas à região e são alternativas promissoras para utilização em programas de melhoramento que visam à obtenção de maior variabilidade potencial para a seleção.

ABSTRACT Sweet corn (Zea mays L.) local varieties are important gene sources for breeding programs, mainly in participatory research models. This study aimed to evaluate the agronomic performance of seven sweet corn local varieties (2255A, 2029A, 2276A, 2514A, 3000A, 741B and 319A) carrying the sugary1 gene under homozygotic condition and two controls, at four environments [Anchieta (altitudes: 422 and 717 m), Guaraciaba (altitude: 624 m) and Florianópolis (altitude: 5 m)], in the Santa Catarina state, Brazil. The varieties 3000A and 319A showed a good performance in the different altitudes for ear and grain length and ear yield. At intermediate altitudes (422 and 624 m), the mean husked ear yield (milky grain) of these varieties were close to 12.5 t ha-1 (3000A) and 10.0 t ha-1 (319A). The varieties 2029A, 741B, 2514A, 2276A and 2255A stood out for ear length and diameter, number of ear rows and grain length. The best performance of the sweet corn local varieties was observed in their region of origin, mainly at altitudes ranging from 400 to 650 m. These varieties are adapted to the region and are promising alternatives to be used in breeding programs focused on finding a greater potential variability for selection purposes.

RESUMO Variedades locais de arroz de sequeiro vêm sendo conservadas por agricultores familiares do oeste catarinense. Contudo, não existem dados na literatura sobre a qualidade e o rendimento industrial dessas variedades, bem como dos efeitos dos genótipos, do ambiente e da interação genótipo x ambiente. Avaliaram-se a renda de benefício e grãos inteiros, quebrados, barrigas brancas e gessados, em experimentos delineados em blocos completos casualizados, com quatro repetições, em dois locais. A renda e a taxa de grãos inteiros e quebrados foram de 57,93-69,90 %, 38,73-66,0 % e 3,40-22,15 %, respectivamente, com 15 variedades locais atingindo valores semelhantes aos obtidos por variedades modernas de arroz de sequeiro. Os maiores valores para renda e grãos inteiros foram obtidos em Anchieta (local de procedência das variedades). Os percentuais de ocorrência de grãos barriga branca e gessados foram de 0,10-8,68 % e 0,02-3,12 %, respectivamente. As diferenças foram significativas (p ≤ 0,05) para os efeitos do genótipo, ambiente e interação genótipo x ambiente, para a renda de benefício. Para grãos inteiros e quebrados, as diferenças foram significativas (p ≤ 0,05) para genótipo e ambiente, mas não para a interação genótipo x ambiente. Para grãos barriga branca e gessados, as diferenças resultaram significativas (p ≤ 0,05) para genótipo e interação, e não significativas para ambiente. Foram observadas diferenças quanto à estabilidade das variedades, em relação a todas as variáveis de rendimento industrial estudadas, e estabelecido um ranking de estabilidade.

ABSTRACT Family farmers in the western Santa Catarina state, Brazil, have conserved local dryland rice varieties. However, the literature lacks data about the milling performance of these varieties, as well as about the effects of genotypes, environment and genotype x environment interaction. The current study aimed to evaluate the milling yield, as well as whole, broken, white-belly and chalky grains, in experiments designed in complete randomized blocks, with four replications, in two sites. The rates for milling yield and whole and broken grains were, respectively, 57.93-69.90 %, 38.73-66.0 % and 3.40-22.15 %, with 15 local varieties reaching values similar to those recorded for modern dryland rice varieties. The Anchieta county (origin of the varieties) recorded the highest values for milling yield and whole grain. The incidence rates for white-belly and chalky grains were, respectively, 0.10-8.68 % and 0.02-3.12 %. Significant differences (p ≤ 0.05) were observed for genotype, environment and genotype x environment interaction effects, concerning the milling yield. For whole and broken grains, the differences were significant (p ≤ 0.05) for genotype and environment, but not significant for genotype x environment interaction. For white-belly and chalky grains, the differences were significant (p ≤ 0.05) for genotype and genotype x environment interaction, but not significant for environment. For all the studied milling yield variables, differences were observed for the varieties' stability, as well as established a stability ranking.

ABSTRACT: A germplasm collection should represent the diversity of the target species and the gene pools associated with it. However, it is critical to establish collection plans which ensure such representativeness. At times it is difficult to identify the best strategy for collecting domesticated species that are conserved in situ/on farm, since, in general, the magnitude of the diversity existing in a geographical area was hitherto unknown. The Diversity Census methodology was developed for previous diagnosis of the diversity of Zea mays subsp. mays L., conserved by farmers in two municipalities in the far western region of the state of Santa Catarina, southern Brazil. The Diversity Census database allowed for the identification of the best strategy to collect different types of maize landraces. Thus, tests were carried out using two methods described for Core Collections (Modified Random Sampling and Maximization) and a third statistical method for random sampling, stratified by farm area. The Maximization method enabled the capture of all the morphological variation of the traits evaluated in the Diversity Census from the smallest sample size. The relevance of this result is the feasibility of adapting the Core Collection strategy in order to plan more efficient expeditions to collect maize landraces conserved in microregions. Such planning allows for organizing the collection work efficiently, reducing costs, simplifying the work of characterization and helping to plan integrated strategies of in situ/on fam conservation.

Resumen En el presente trabajo se evaluaron la productividad de granos (GY), la capacidad de expansión (PE), la capacidad de expansión sin el peso de los granos no reventados (PEW), además de otras 11 características agronómicas y morfológicas de 14 variedades locales de maíz (Zea mays L.) ‘pira’ (LPV) provenientes del extremo oeste de Santa Catarina, en el sur de Brasil. Utilizando un delineamiento experimental de bloques completos al azar con tres repeticiones se realizaron dos experimentos, en dos regiones diferentes del estado de Santa Catarina; un primer ensayo en Florianopolis (litoral este) y un segundo ensayo en el municipio de Anchieta (extremo oeste). La mayor correlación positiva se observó entre productividad y prolificidad (PRL) (r = 0.72) seguida de la productividad vs. el número de granos por fila (NGR) (r = 0.71), mientras que con el índice de circularidad de la cariópside (CCI) la correlación fue negativa (r = -0.67). La variable (PEW) mostro correlación positiva con CCI (r = 0.70) y con la relación espesor/largo (TWR) (r = 0.70). La variedad de maíz pira 574A se destacó por sus altos valores de PE y PRL. El mejoramiento de poblaciones compuestas y de poblaciones per se es una estrategia de selección potencial para LPV, basada en la complementariedad y correlación entre las variables y los valores de GY, PE, PEW, TWR CCI - HEP - relación entre altura de la primera mazorca/altura de la planta; PH - altura de la planta; PRL - WHG - peso de 100 gramos; VHG - volumen de 100 gramos; EL - longitud de la mazorca; NRE - numero de filas por mazorca; NGR - ED - diámetro de la mazorca.

Abstract The aim of this study was to evaluate grain yield (GY), popping expansion (PE), popping expansion disregarding the weight of unpopped kernels (PEW), and eleven other agronomic and morphological traits of 14 local popcorn varieties (LPV) from far west of the state of Santa Catarina, Southern Brazil. Two experiments were carried out, in a completely randomized block design with three replications, in different regions of Santa Catarina: one in the municipality of Florianópolis (east coast) and the other in Anchieta (western). Grain yield had the highest positive correlation with prolificacy (PRL) (r = 0.72) and number of grains per row (NGR) (r = 0.71), and a negative correlation with caryopsis circularity index (CCI) (r = -0.67). Variable PEW showed a positive correlation with CCI (r = 0.70) and with thickness/width ratio (TWR) (r = 0.70). Variety 574A stood out for high PE and PRL. The improvement of composite populations and of populations per se is a potential breeding strategy for LPV, based on the complementarity and correlation among variables and the GY, PE, and PEW values, CCI - HEP - first ear height/plant height relation, PH - plant height; PRL - WHG - weight of 100 grains; VHG - volume of 100 grains; EL - ear length; NRE - number of rows per ear; NGR - number of grains per row of ear; ED - ear diameter.

Local maize (Zea mays L.) varieties are cultivated by small-scale farmers in western Santa Catarina (SC) State, in southern Brazil. These small areas frequently present many problems related to biotic and non-biotic stresses, which have limited the economic output and income of the farmers. Production from local varieties for human consumption would be an alternative way of improving income and stimulating on farm conservation. The genetic variability of the total carotenoid content (TCC) of kernels in a local maize population was evaluated for their economic exploitation potential as biofortified food. Two independent samples of 96 half-sib families (HSF) plus four checks were evaluated in two groups of experiments in western SC and each one was carried out in two environments. They were set out in a 10 × 10 partially balanced lattice with three replications per location; plots consisted of one row, 5.0 m long with 1.0 m between rows. TCC ranged from 11 to 23 µg g-1, averaging ≈16 µg g-1 in the pooled analysis over the two sets. The local composite population exhibited genetic variability in order to increase the TCC of grains in the second cycle of selection by the convergent-divergent scheme.

A alface (Lactuca sativa L.) é a hortaliça folhosa mais consumida na alimentação do brasileiro, sendo boa fonte de vitaminas e de sais minerais. É largamente produzida no sistema convencional. No entanto, o cultivo hidropônico vem ganhando espaço no mercado, conquistando a confiança dos consumidores, cada vez mais exigentes com a qualidade dos alimentos. O objetivo deste trabalho foi avaliar o desempenho de duas cultivares de alface, nos sistemas de cultivo hidropônico e convencional, para a produção de massa fresca (MF) e massa seca (MS), fotossíntese, teores de antocianinas e de clorofilas. Foram conduzidos dois experimentos: um no sistema de cultivo hidropônico (CH) e outro em cultivo convencional (no solo) (CC), realizados em ambientes protegido e desprotegido, respectivamente, no município de Florianópolis, SC. A cultivar Mimosa Verde (MV) apresentou maior peso de massa fresca, em comparação com Mimosa Roxa (MR), em ambos os sistemas de produção, e ambas as cultivares apresentaram melhor desempenho no sistema hidropônico (287,7 g MV e 139,1 g MR), em relação ao convencional (129,7 g MV e 111,8 g MR). A cultivar MV apresentou menores teores médios de clorofila total (7,7 mg g-¹ MF), quando comparada com MR (11,8 mg g-¹ MF) e ambas apresentaram teores médios mais elevados dessa variável no cultivo hidropônico. Para a cultivar MR, os teores de antocianinas, no cultivo convencional, foram superiores (88,24 mg g-¹ MF) aos do cultivo hidropônico (36,89 mg g-¹ MF). Os melhores resultados para a taxa de assimilação líquida de CO2, com relação à densidade de fluxo de fótons fotossinteticamente ativos, foram observados no cultivo hidropônico, para ambas as cultivares. Também se observou variação nos teores de clorofila, que foram maiores no ambiente protegido do sistema hidropônico, e antocianinas, que foram maiores no cultivo convencional.

Lettuce (Lactuca sativa L.) is the most commonly consumed leaf vegetable in the Brazilian diet, and it is a good source of vitamins and minerals. It is widely grown in the conventional farming system. However, the hydroponic farming system has been gaining importance in the market, wining confidence from consumers, who are becoming increasingly more demanding on food quality. The objective of this study was to evaluate the performance of two lettuce cultivars on hydroponic and conventional farming systems for the production of fresh mass (FM) and dry mass (DM), photosynthesis, contents of chlorophyll and anthocyanin. The following two experiments were carried out: hydroponics farming (HF) and conventional farming (CF), performed in protect and unprotect environments, respectively, in Florianópolis, SC. Mimosa Verde cultivar (MV) showed greater fresh mass than Mimosa Roxa (MR), in both farming systems and the two cultivars presented better performance in the hydroponic system (287.7 g MV and 139.1 g MR) than the conventional system (129.7 g MV and 111.8 g MR). Mimosa Verde cultivar presented lower average contents of total chlorophyll (7.7 mg g-¹ FM) than Mimosa Roxa (11.8 mg g-¹FM), and both cultivars displayed higher means for this variable in the hydroponic farming system. Mimosa Roxa presented higher contents of anthocyanin in the conventional system (88.24 mg g-¹ FM) than the ones in the hydroponic system (36.89 mg g-¹ FM). The best results for CO2 net assimilation rate regarded to photosyntheticaly active photon flux density were found in the hydroponic system, for both lettuce cultivars. Variation in the contents of chlorophyll were also found. Those variations were higher in the protected system than in the hydroponic system and contents of anthocyanin were higher in the conventional system.

We used 125 microsatellite markers to genotype the maize (Zea mays L.) near isogenic lines (NIL) L30HtPHtPRtRt and L30htphtpRtRt and the L40htphtprtrt line which contrast regarding the presence of the recently described dominant HtP and the recessive rt genes that confer resistance to Exserohilum turcicum. Five microsatellite markers revealed polymorphisms between the NIL and were considered candidate linked markers for the HtP resistance gene. Linkage was confirmed by bulked segregant sample (BSS) analysis of 32 susceptible and 34 resistant plants from a BC1F1 population derived from the cross (L30HtPHtPRtRt x L40htphtprtrt) x L40htphtprtrt. The bnlg198 and dupssr25 markers, both located on maize chromosome 2L (bin 2.08), were polymorphic between bulks. Linkage distances were estimated based on co-segregation data of the 32 susceptible plants and indicated distances of 28.7 centimorgans (cM) between HtP and bnlg198 and 23.5 cM between HtP and dupssr25. The same set of susceptible plants was also genotyped with markers polymorphic between L30HtPHtPRtRt and L40htphtprtrt in order to find markers linked to the rt gene. Marker bnlg197, from chromosome 3L (bin 3.06), was found linked to rt at a distance of 9.7 cM. This is the first report on the chromosomal locations of these newly described genes.

The use of monogenic race-specific resistance is widespread for the control of maize (Zea mays L.) helminthosporiosis caused by Exserohilum turcicum. Inoculation of 18 Brazilian isolates of E. turcicum onto elite maize lines containing previously identified resistance genes and onto differential near-isogenic lines allowed the identification of new qualitative resistance genes. The inoculation of one selected isolate on differential near-isogenic lines, F1 generations and a BC1F1 population from the referred elite lines enabled the characterization of the resistance spectrum of three new genes, one dominant (HtP), one recessive (rt) and a third with non-identified genetic action. Three physiological races of the pathogen were also identified including two with new virulence factors capable of overcoming the resistance of one of the resistance genes identified here (rt).

Locos de microssatélites são úteis como marcadores genéticos pois são numerosos, ocorrem em todos os cromossomos e possuem um alto nível de polimorfismo. Além disso, podem ser amplificados por meio da PCR e resolvidos em géis de agarose. O maior problema, no entanto, reside no fato de que os primers utilizados em sua amplificação apresentam diferentes comprimentos e composição de nucleotídeos, o que gera a necessidade de otimizar programas de PCR para cada loco. Este trabalho descreve programas de PCR "touchdown" utilizados com sucesso na amplificação de um conjunto de 125 locos de microssatélites de milho escolhidos por serem representativos de todos os cromossomos. Os programas variaram tanto em relação à temperatura de anelamento (Tm), como na concentração dos primers. Assim, os primers puderam ser agrupados em quatro grupos: um grupo maior, constituído por primers que mostraram boa amplificação quando utilizados em um programa básico já publicado porém com concentrações diferentes de primers; um segundo grupo que amplificou em programas alternativos, nos quais as Tm foram modificadas de modo a incluir as Tm de ambos os primers ou a maior Tm do par de primers, estimadas em base da composição nucleotídica dos primers; um terceiro grupo foi composto por primers que amplificaram em programas com Tm mais elevadas que as estimadas, e um quarto grupo, com apenas dois pares de primers, em que a situação oposta ocorreu.

Maize (Zea mays L.) microsatellite loci are useful as genetic markers because they are numerous, occur in every chromosome, and have a high content of polymorphism information. Furthermore, they can be amplified by PCR and the resulting fragments resolved on agarose gels. A major problem, however, is that the primers used in their amplification often have different length and nucleic acid content, requiring optimization of PCR amplification programs for each locus. We developed "touchdown" PCR programs successfully used in the amplification of a set of 125-maize microsatellite loci, chosen as representative of all chromosomes. The programs varied both in relation to the annealing temperature (Tm) and primer concentration. Primers could be divided into four groups. A large group included primers that amplified well in a basic previously published amplification program but with different primer concentrations. A second group amplified in alternative programs in which the annealing temperatures were changed so as to include the Tm of either both primers or the highest Tm of the primer pair estimated based on their nucleotide composition. A third group included primers that amplified in programs with Tm higher than those estimated, and in a fourth group, with just two pairs of primers, the opposite situation prevailed.