Showing papers in "Crop Breeding and Applied Biotechnology in 2013"
TL;DR: It is indicated that a high level of resistance against various ASR isolates could be retained in lines carrying the three Rpp genes in susceptible genetic backgrounds, although minor influences of plant genetic background and ASR pathogenicity to the ASR resistance could occur.
Abstract: In this study, the influence of genetic background on the resistance level of a soybean line carrying Rpp2, Rpp4, and Rpp5 was evaluated by backcrossing it with a susceptible variety. It was also evaluated eight lines which carry these Rpp genes against five Asian soybean rust (ASR) isolates, in order to determine the likely range of resistance against ASR isolates differing in pathogenicity. The results indicated that a high level of resistance against various ASR isolates could be retained in lines carrying the three Rpp genes in susceptible genetic backgrounds, although minor influences of plant genetic background and ASR pathogenicity to the ASR resistance could occur. Thus, lines with the pyramided three Rpp genes should be effective against a complex pathogen population consisting of diverse Phakopsora pachyrhizi isolates.
44 citations
TL;DR: It was concluded that the plant growth regulators can be successfully employed to enhance the yield in this economically important oil seed crop.
Abstract: The commercial importance of linseed (Linum usitatissimum L.) has attracted breeders to increase its seed yield using various breeding approaches. Plant growth regulators (PGRs) have a significant role in enhancing yield and its related traits in linseed. In the present study, two plant growth hormones, auxin and gibberellic acid, were applied individually, as well as in combinations, in order to study their effect on yield and its components in "Neelam", which is a high yielding variety of linseed. A comparative study was done under pot and field condition. A combined dose of auxin (1.0 mg L-1) and gibberellin (200 mg L-1) is recommended for the enhancement of seed yield, whereas a 0.5 mg L-1 dose of auxin is recommended for the enhancement of vegetative growth. It was concluded that the plant growth regulators can be successfully employed to enhance the yield in this economically important oil seed crop.
43 citations
TL;DR: The purpose of this work was to evaluate a methodology of adaptability and phenotypic stability of alfalfa genotypes based on the training of an artificial neural network considering the methodology of Eberhart and Russell.
Abstract: The purpose of this work was to evaluate a methodology of adaptability and phenotypic stability of alfalfa genotypes based on the training of an artificial neural network considering the methodology of Eberhart and Russell. Data from an experiment on dry matter production of 92 alfalfa genotypes (Medicago sativa L.) were used. The experimental design constituted of randomized blocks, with two repetitions. The genotypes were submitted to 20 cuttings, in the growing season of November 2004 to June 2006. Each cutting was considered an environment. The artificial neural network was able to satisfactorily classify the genotypes. In addition, the analysis presented high agreement rates, compared with the results obtained by the methodology of Eberhart and Russell.
40 citations
TL;DR: High level of polymorphism and two major diversity clusters were identified and the diversity may be increased, because a new threshold in the genetic gains is expected on breeding programs with the intensification of the use of conserved germplasm.
Abstract: This work aimed to characterize accessions that represent the C. canephora germplasm conserved and cultivated in Brazil. A total of 130 accessions from germplasm banks of IAC (Sao Paulo), UFV (Minas Gerais) and also collected in plantations of the State of Espirito Santo and Rondonia were evaluated with a set of 20 new microsatellite primers. Multivariate methods were used to estimate the relationship among the accessions. High level of polymorphism and two major diversity clusters were identified. First cluster was composed by the accessions conserved in the IAC and UFV collections and the second was formed by accessions collected in areas under cultivation. Accessions from Espirito Santo and Rondonia were clear separated, composing two subclusters. Despite the great polymorphism found in Brazilian plantations, the diversity may be increased, because a new threshold in the genetic gains is expected on breeding programs with the intensification of the use of conserved germplasm.
37 citations
TL;DR: Evaluating sugarcane genotypes for the trait tons of sugar per hectare (TSH), stratifying five production environments in the state of Parana found RB006970, RB855156 and RB855453 as the genotypes with highest TSH and Sao Pedro do Ivai as the environment with the greatest GE interaction.
Abstract: The purpose of this study was to evaluate sugarcane genotypes for the trait tons of sugar per hectare (TSH), stratifying five production environments in the state of Parana. The performance of 20 genotypes and 2 standard cultivars was analyzed in three consecutive growing seasons by the statistical methods AMMI and GGE Biplot. The GGE Biplot grouped the locations into two mega-environments and indicated the best-performing genotypes for each one, facilitating the selection of superior genotypes. Another advantage of GGEBiplot is the definition of an ideal genotype (G) and environment (E), serving as reference for the evaluation of genotypes and choice of environments with greater GE interaction. Both models indicated RB006970, RB855156 and RB855453 as the genotypes with highest TSH and Sao Pedro do Ivai as the environment with the greatest GE interaction. Both approaches explained a high percentage of the sum of squares, with a slight advantage of AMMI over GGE Biplot analysis.
31 citations
TL;DR: NCl and ThCl had a direct effect on GMY and can be used for indirect selection or as secondary traits in the selection process, and it is possible to select a palm variety with high DMY and DM.
Abstract: The objectives of this study were to evaluate the relationships between morphological characteristics and fresh matter yield of cactus pear and identify their direct and indirect effects. Nineteen accessions were evaluated for the following traits: number (NCl), thickness (ThCl), length (LCl) and width (WCl) of cladodes, plant height (PH) and plant width (PW), and green matter yield (GMY), dry matter yield (DMY) and dry matter percentage (DM). The correlations were estimated, and path analysis was performed by the method proposed by Wright. GMY was strongly correlated with DMY, allowing indirect selection for this trait. NCl and ThCl had a direct effect on GMY and can be used for indirect selection or as secondary traits in the selection process. Given the lack of significant correlations between MS and DMY, it is possible to select a palm variety with high DMY and DM.
30 citations
TL;DR: The aim of this work is to present the features of the popcorn cultivar UENF 14, developed from five cycles of recurrent selection of the population UNB-2U, to the scientific community.
Abstract: The aim of this work is to present the features of the popcorn cultivar UENF 14, developed from five cycles of recurrent selection of the population UNB-2U, to the scientific community. The cultivar produces yields of 3047.58 kg ha-1 and has popping expansion of 35.69 mL g-1.
29 citations
TL;DR: Yield research showed this is an effective way in rice breeding to control the damage from BPH and RSD, by using MAS of BPH genes and Stv-bi gene.
Abstract: Rice is affected by several plant diseases and insects that can cause severe yield losses. In this study, it is reported the introgression of resistance genes to brown planthopper (BPH) and rice stripe disease (RSD) in the japonica cultivars. Initially, four backcross (BC) lines were obtained using B5 as donor parent. Molecular markers linked to the resistance genes were used to identify the plants containing the genes of interest. In the present research, two BPH resistance genes (Bph14 and Bph15) and one RSD resistance gene (Stv-bi) were successfully transferred into three japonica varieties via a marker-aided backcrossing procedure. The progeny lines with Bph14 and Bph15 genes showed high resistance to BPH, while the progeny lines with Stv-bi gene showed high resistance to RSD. Yield research showed this is an effective way in rice breeding to control the damage from BPH and RSD, by using MAS of BPH genes and Stv-bi gene.
29 citations
TL;DR: According to the Annicchiarico methodology analysis, genotypes CMSXS634, BRS506, and CMSxS646 were the most stable and adapted for FBY and TSS concomitantly; CMSX S634 being more adapted to favorable environments and CMSS646 being moreadapted to unfavorable environments.
Abstract: The objective of this study was to evaluate the phenotypic stability and adaptability of 25 sweet sorghum cultivars of Embrapa Maize and Sorghum. The experiments were conducted in five Brazilian environments, three in the state of Minas Gerais, and the others in Sinop, Mato Grosso and Pelotas, Rio Grande do Sul. Fresh biomass yield (FBY), and total soluble solids (TSS) of the juice were evaluated in a randomized complete block design with three replications. Analysis of variance showed significant genotype by environment interaction for both traits. According to the Annicchiarico methodology analysis, genotypes CMSXS634, BRS506, and CMSXS646 were the most stable and adapted for FBY and TSS concomitantly; CMSXS634 being more adapted to favorable environments and CMSXS646 being more adapted to unfavorable environments.
26 citations
TL;DR: The aim of this study was to determine genetic parameters for straightness of the trunk of Eucalyptus cladocalyx with a view to the selection of straight trees, while keeping the impact on growth minimal.
Abstract: The aim of this study was to determine genetic parameters for straightness of the trunk of Eucalyptus cladocalyx, with a view to the selection of straight trees, while keeping the impact on growth minimal. The tests were conducted at two locations in the semi-arid region of Chile, using a randomized block design, with 30 replications and 49 half-sib families. The parameters were estimated by a bi-character model of individual trees, using Bayesian inference by Gibbs algorithm. The heritability for stem straightness was shown to be moderate, with h2=0.40 [0.29-0.57]. Heritabilities for diameter and height were moderate: 0.30 [0.24-0.38] and 0.30 [0.22-0.44]. Genetic correlations between straightness and growth were statistically not different from zero. The genotype-environment interaction was not significant (p>0.05) for the traits. The moderate degree of genetic control allows significant genetic gains in environments under water stress.
18 citations
TL;DR: It is reported for the first time the existence of Pm-x3 and the genetic locations of these resistance genes from PI 414723, which are resistant to races 1, 3 and 5 and it is a suitable source of resistance genes.
Abstract: The fungus Podosphaera xanthii affects melon crops and presents several races controlled by race-specific resistance genes. The accession PI 414723 is resistant to races 1, 3 and 5 and it is a suitable source of resistance genes. The inheritance of resistance to these races was analyzed on 87 F2 plants from the cross of PI 414723 × Vedrantais, and resistance to all three races could be explained by the segregation of a single dominant gene, although a digenic model could also be accepted. A genetic map was assembled with 206 markers, and co-segregation analysis of resistance phenotypes indicated the existence of two linked loci in linkage group II, one conferring resistance to races 1 and 5 (denominated Pm-x1,5), and the second to race 3 (denominated Pm-x3), located 5.1 cM apart. This study reports for the first time the existence of Pm-x3 and the genetic locations of these resistance genes from PI 414723.
TL;DR: Changes in the last two traits caused an extension of the period from the emergence of the first pistillate/perfect to the first staminate flower from 0.1 to 21.57 days, which represents the strongest effect of ethrel.
Abstract: Seven traits related to flowering and sex expression in melon were studied and their reaction to application of two growth regulators (ethrel and gibberellic acid) was observed. Four monoecious genotypes (Sesame, ED-3, ED-4, Pobeditel) and four andromonoecious genotypes (Chinese muskmelon, Anannas, Fiata, A2-3lb) had been used for experiments. According to the results, ethrel had higher effects on the investigated traits than gibberellic acid. Ethrel increased the number of perfect flowers per plant for 7.18 (31.42%), reduced the number of male flowers per plant for 21.47 (17.98%), affected earlier appearance of the first pistillate/perfect flower for 3.68 days, and delayed the appearance of the first staminate flower for 16.07 days. Changes in the last two traits caused an extension of the period from the emergence of the first pistillate/perfect to the first staminate flower from 0.1 to 21.57 days, which represents the strongest effect of ethrel. Gibberellic acid had generally opposite effects on the studied traits.
TL;DR: Two progenies proved their superiority for the breeding program for they combine the traits of resistance and favorable grain type, which are essential for commercial acceptance.
Abstract: A backcross breeding program between commercial common bean cultivars (VC3 and M20) and sources of resistance (Ex-Rico 23 and G122) was conducted with a view toward selecting carioca (beige with brown stripes) progenies resistant to white mold. Forty-eight progenies (27 F2:6 BC1 and 21 F1:5 BC2) were evaluated for yield, growth habit, grain type and pathogen response by two methodologies for assessment ("straw test" and "oxalic acid"). The methods were effective in discriminating the progenies, showing differing results, for they may assess different resistance mechanisms. Thus, they should be used together. Simultaneous selection for yield, growth habit, grain type and white mold resistance proved to be viable. The most appropriate strategy was to use lower intensities of selection and prioritize traits such as resistance and grain type, which are essential for commercial acceptance. Two progenies proved their superiority for the breeding program for they combine the traits of resistance and favorable grain type.
TL;DR: Fusarium oxysporum f.
Abstract: Fusarium oxysporum f. sp. vasinfectum (FOV) is one the most destructive okra (Abelmoschus esculentus) pathogens in Brazil. Fifty-four okra accessions were evaluated for resistance to FOV. Greenhouse screening was initially carried out with one FOV isolate ('Fus-194'). Inoculation (in all assays) was carried out with 21-day-old plantlets, using the root-dipping inoculation technique. Thirty-three accessions displaying differential responses in the first screening were re-evaluated in two additional assays, using two FOV isolates ('Fus-194' and 'Fus-201'). Twelve accessions were rated as highly to intermediately resistant to 'Fus-194' during the dry/moderate temperature season, whereas nine accessions were classified as highly to intermediately resistant to 'Fus-201'. In the assay carried out in the wet and warm season, 72% of the accessions were classified as having high and intermediate resistance to 'Fus-194', and 32% were resistant to 'Fus-201'. The accessions 'Santa Cruz-47', 'BR-2399' and 'BR-1449' were the most promising resistance sources.
TL;DR: As metodologias de associacao dos individuos de acordo com a populacao de referencia e com base na analise fatorial de correspondencia forneceram resultados semelhantes and revelam um alto nivel de diversidade genetica nas populacoes brasileiras.
Abstract: A diversidade genetica em dez populacoes de coqueiro gigante do Brasil foi determinada utilizando 13 marcadores microssatelites. Foi detectado um total de 68 alelos, com media de 5,23 alelos por loco. A media da heterozigosidade esperada e observada foi 0,459 e 0,443 respectivamente. O numero de locos por populacao variou de 36 a 48, com media de 40,9 locos. Foram encontrados 12 alelos exclusivos e destes, um foi considerado como alelo raro esporadico e oito como alelos raros localizados. As metodologias de associacao dos individuos de acordo com a populacao de referencia e com base na analise fatorial de correspondencia forneceram resultados semelhantes e permitiram a formacao de dois grupos, o primeiro formado pelas populacoes de Baia Formosa, Georgino Avelino e Sao Jose do Mipibu e o segundo pelas populacoes de Japoata, Pacatuba e Praia do Forte. Esses resultados revelam um alto nivel de diversidade genetica nas populacoes brasileiras.
TL;DR: O programa da North Dakota State University (NDSU) iniciou o desenvolvimento de hibridos que apresentem alto conteudo de proteina atraves do projeto de milho precoce com altoconteudo of proteina de qualidade (EarlyQPMF).
Abstract: Maize has become a profitable alternative for North Dakota (ND) farmers and ranchers. However, U.S. northern industry hybrids still lack cold and drought stress tolerance as well as adequate grain quality for ethanol and feedstock products. Moreover, there is a need to increase the value of feedstock operations before and after ethanol utilization. The ND maize breeding program initiated the development of hybrids with high quality protein content through the Early Quality Protein Maize for Feedstock (EarlyQPMF) project. The North Dakota State University (NDSU) maize breeding program acts as a genetic provider to foundation seed companies, retailer seed companies, processing industry, and breeders nationally and internationally. In the past 10 years, NDSU was awarded 9 PVP maize certificates and released 38 maize products. Within those, 13 inbred lines were exclusively released to a foundation seed company for commercial purposes. In addition, 2 hybrids were identified for commercial production in central and western ND.
TL;DR: The impacts of the adoption of transgenic technology in the arrangements of maize breeding programs and seed production sector in Brazil are analyzed and a critical analysis of the situation of the breeding programs that do not have this technology is made.
Abstract: Transgenic maize was approved in Brazil in 2008/2009. In 2012, it occupied 73% of the country maize growing area. This high adoption rate confirms studies indicating that technology use has been the major driving force in Brazilian agriculture. Maize seed market in the world has been a concentrated sector. Although, when this sector is associated with transgenesis, this concentration increases sharply. In one side, there is the idea that companies can benefit from gains of scale and complementarities to maximize their efficiency in research and development (R&D). On the other side, this concentration may allow the exercise of "market power" by dominant companies. The objective of this study is to analyze the impacts of the adoption of transgenic technology in the arrangements of maize breeding programs and seed production sector in Brazil. A critical analysis of the situation of the breeding programs that do not have this technology is made.
TL;DR: After two cycles of recurrent selection in red bean breeding and of obtaining new lines, genetic progress, in the mean value of the crop seasons, was 7.5% forgrain yield, 7% for grain appearance, 33.4% for resistance to rust and 13.2% for Resistance to angular leaf spot.
Abstract: This study was carried out for the purpose of estimating genetic progress after two cycles of recurrent selection in red bean breeding and of obtaining new lines. In cycle zero, F3:5 and F3:6 families were evaluated. In cycle one, the families were extracted in generation F5 and evaluated in generations F5:6 and F5:7. As the families were evaluated in different years and generations, the estimate of genetic progress was obtained by simultaneously evaluating the 30 best lines obtained at the end of each cycle in experiments conducted through three crop seasons. After two cycles of recurrent selection, genetic progress, in the mean value of the crop seasons, was 7.5% for grain yield, 7% for grain appearance, 33.4% for resistance to rust and 13.2% for resistance to angular leaf spot. Lines of red beans were obtained with potential for being included in future Value for Cultivation and Use (VCU) testing for Minas Gerais, Brazil.
TL;DR: There were differences among the wheat adaptation regions in terms of the efficiency of the Papadakis method, the adjustment coefficient of the genotype averages and the increases in the selective accuracy of grain yield.
Abstract: The aim of this study was to verify whether using the Papadakis method improves model assumptions and experimental accuracy in field trials used to determine grain yield for wheat lineages indifferent Value for Cultivation and Use (VCU) regions. Grain yield data from 572 field trials at 31 locations in the VCU Regions 1, 2, 3 and 4 in 2007-2011 were used. Each trial was run with and without the use of the Papadakis method. The Papadakis method improved the indices of experimental precision measures and reduced the number of experimental repetitions required to predict grain yield performance among the wheat genotypes. There were differences among the wheat adaptation regions in terms of the efficiency of the Papadakis method, the adjustment coefficient of the genotype averages and the increases in the selective accuracy of grain yield.
TL;DR: NS had the greatest direct effect on SW in all the analyses with the use of genetic and phenotypic correlations and in 12 analyses with use of the genotypic correlation.
Abstract: The aim of this research was to evaluate the consistency of path analyses in sugarcane experiments based on genetic, phenotypic and genotypic correlations. Forty-four analyses were made with a view toward quantifying the direct and indirect effects of stalk height (SH), stalk diameter (SD) and number of stalks (NS) on sugarcane weight (SW). NS had the greatest direct effect on SW in all the analyses with the use of genetic and phenotypic correlations and in 12 analyses with use of the genotypic correlations. SD had a high direct effect on SW, going beyond NS in only one experiment, while SH had the lowest direct effect on SW in most of the experiments. The results showed greater consistency with the use of genetic and phenotypic correlations. In the balanced experiments, the phenotypic and genetic correlations showed equivalent results. NS is the main determinant of changes in sugarcane production.
TL;DR: This study characterize subsamples of determinate growth lima bean in morpho-agronomic terms and estimate genetic divergence, identifying pairs of divergent and complementary genotypes for crosses and identifying traits related to production of importance for variability.
Abstract: – Lima bean, a highly important legume, serves as a source of protein, reducing nutritional dependency on meat and other beans, especially for needy populations. This crop, with production concentrated in the Northeast of Brazil, has been the subject of very few studies, considering the evaluation of varieties predominantly with indeterminate growth habit. The characterization of ma -terial presenting determinate growth, an agronomically important characteristic, may subsidize breeding programs. We characterize subsamples of determinate growth lima bean in morpho-agronomic terms and estimate genetic divergence. We identified pairs of divergent and complementary genotypes for crosses. The genotypes were grouped in six and five groups in regard to the Tocher and UPGMA methods, respectively, for the quantitative traits. For the qualitative traits, three groups were formed. Analyses of canonical variables identified traits related to production of importance for variability. The study shows the importance of characterization of
TL;DR: The objective of this work is to carry out a bibliographic review on the topic, to sensitize researchers in the area of soybean breeding about its importance and to improve soybean production for human consumption.
Abstract: Soybean is an extensive crop that produces more protein per hectare and, compared to other sources, has the lowest protein cost. This turns soybean into one of the basic foods with the potential to fight malnutrition and hunger in the planet. Even though it represents the fourth crop in grain production in the world (261 million tons year-1), most of its production is used as animal fodder. Currently, one of the greatest research challenges is to improve soybean production for human consumption. Cooking time is one the several characteristics that need improvement so that soybean can be used more extensively in our everyday diet. The objective of this work is to carry out a bibliographic review on the topic, to sensitize researchers in the area of soybean breeding about its importance.
TL;DR: The coincidence between the best and worst populations in the two growing seasons and different generations for the two characters was low, indicating that the environmental effect interferes with the selection of common bean populations when using the method of Jinks and Pooni.
Abstract: The objective of this study was to investigate the effect of environments on the estimated genetic potential of common bean populations for the traits hypocotyl diameter and grain yield. We evaluated 48 segregating bean populations in the growing seasons winter 2009 (F2 and F3 simultaneously) and drought 2010 (F3 and F4 generations simultaneously), and 16 controls. The genetic potential of the population was estimated using the methodology of Jinks and Pooni. The coincidence between the best and worst populations in the two growing seasons and different generations for the two characters was low, indicating that the environmental effect interferes with the selection of common bean populations when using the method of Jinks and Pooni. Thus, it is recommended that the genetic potential should be estimated based on the evaluation of a larger number of environments.
TL;DR: BRS Savanna, a cross between V. Morales x IF200113, is a spring andan early-maturing six-rowed barley, widely adapted to irrigated areas of the savanna, in Central Brazil, which presents production stability and the industrial quality, grain yield and lodging resistance are high.
Abstract: BRS Savanna, a cross between V. Morales x IF200113, is a spring andan early-maturing six-rowed barley, widely adapted to irrigated areas of the savanna, in Central Brazil. It presents production stability and the industrial quality, grain yield and lodging resistance are high. It is suitable for cultivation in the states of GO, MG and DF.
TL;DR: Os marcadores SSR foram eficientes na selecao de genotipos geneticamente diversos apesar da similaridade fenotipica a as linhagens PF 9027, PF 950351, PF 030132, PF 979002, PF 040488 e IWT 04019 podem ser utilizadas como parentais em cruzamentos induzidos considerando variabilidade genet
Abstract: Parental selection is an important step in breeding programs, and genetic variability increases the chances of obtaining variance in progenies. The objectives of this study were to phenotype 29 wheat genotypes and determine the genetic variability among them, in order to identify potential parental lines for breeding programs at Embrapa Wheat. For phenotyping, traits such as plant height, cycle and grains characteristics were assessed and the data were analyzed by the Euclidean distance. The genetic distance was estimated using 97 microsatellite molecular markers and the data were analyzed by Nei72 coefficient. The average distance observed for phenotyping was 10.1, and the genetic distance was 31 %. SSR markers were efficient for selecting genetically diverse genotypes despite their phenotypic similarity, and lines PF 9027, PF 950351, PF 030132, PF 979002, PF 040488 and IWT 04019 can be used as parental for future crosses, since they have genetic diversity and suitable agronomic traits.
TL;DR: The results showed genetic differentiation among populations, and gene flow, and a cluster analysis showed that individuals of P. raimondii populations located in different mountain systems could be grouped together, suggesting long distance dispersal.
Abstract: Puya raimondii, the giant Peruvian and Bolivian terrestrial bromeliad, is an emblematic endemic Andean species well represented in Huascaran National Park in Peru. This park is the largest reserve of puna (high altitude plateau) vegetation. The objective of this study is to report on genetic variation in populations of P. raimondii from Huascaran and neighboring areas. AFLP profiles with four selective primer combinations were retrieved for 60 individuals from different zones. Genetic variability was estimated and a total of 172 bands were detected, of which 79.1% were polymorphic loci. The results showed genetic differentiation among populations, and gene flow. A cluster analysis showed that individuals of P. raimondii populations located in different mountain systems could be grouped together, suggesting long distance dispersal. Thus, conservation strategies for P. raimondii have to take into account exchange between populations located far apart in distance in order to preserve the genetic diversity of this showy species.
TL;DR: The results showed that values for the characteristics analyzed in 2008, 2009 and 2010 were always higher in the field than in the greenhouse conditions, and it is suggested that this negatively affects the reproductive characteristics analyzed.
Abstract: The aim of the present study was to evaluate the possible effect of environmental factors on meiosis, meiotic index, pollen viability and in vitro germination of pollen from stock plants of the rootstocks Trifoliate, 'Swingle', 'Troyer', 'Fepagro C13', 'Fepagro C37' and 'Fepagro C41' grown in a protected environment in comparison with stock plants grown in the field. The results showed that values for the characteristics analyzed in 2008, 2009 and 2010 were always higher in the field than in the greenhouse conditions. In the field, the average of normal meiotic cells was 60.05%, 44.44% and 60.12%, respectively, and in the greenhouse, 52.75%, 30.95% and 52.82%, respectively. Mean pollen viability in the field was 90.28%, 56.23% and 74.74%, and, in the greenhouse, 64.25%, 41.41% and 66.71%, respectively. As temperature oscillations were higher in the greenhouse than in the field, we suggest that this negatively affects the reproductive characteristics analyzed.
TL;DR: The study demonstrated the feasibility of chemical mutagenesis in mutation breeding programme on poppy by demonstrating enhanced univalent frequency per cell with unequal separation at Anaphase I, which suggests that EMS can act as a potential tool in the development of male sterile lines.
Abstract: – Cytological investigation of EMS (ethyl methane sulphonate) treated population demonstrated enhanced univalent frequency per cell with unequal separation at Anaphase I. In contrast to controlled plants, medium strong type desynaptic plants were obtained from 0.6 % EMS treated set, revealing high frequency of univalents at Metaphase I, along with bivalents, which were loosely paired. The univalents remained unpaired till the end of meiosis, leading to formation of micronuclei and abnormal tetrads. These plants had high pollen inviability and sterile seeds. It might be possible that EMS had acted on some genes responsible for chiasma formation, resulting in early chiasma dissociation, which suggests that EMS can act as a potential tool in the development of male sterile lines. The study demonstrated the feasibility of chemical mutagenesis in mutation breeding programme on poppy ( Papaver somniferum L .). Key words : Desynapsis, ethyl methane sulphonate, Papaver somniferum . Crop Breeding and Applied Biotechnology 13: 363-366 2013Brazilian Society of Plant Breeding. Printed in Brazil
TL;DR: BRS Esteio is a common bean cultivar with black grains of excellent cooking quality, suited for cultivation in 21 Brazilian States, and has a high yield potential, upright growth, tolerance to lodging, and moderate resistance to anthracnose.
Abstract: BRS Esteio is a common bean cultivar with black grains of excellent cooking quality, suited for cultivation in 21 Brazilian States. In 77 trials of Value for Cultivation and Use, the cultivar had a normal cycle (90 days), an average yield of 2,529 kg ha-1, which is 8.1% higher than that of the control cultivars, a high yield potential (4,702 kg ha-1), upright growth, tolerance to lodging, and moderate resistance to anthracnose.
TL;DR: The 32 cacao clones selected as being resistant following the witches' broom epidemic and for having distinct productivity were characterized according to their genetic diversity and submitted to a new selection.
Abstract: The 32 cacao clones selected as being resistant following the witches' broom epidemic and for having distinct productivity were characterized according to their genetic diversity and were submitted to a new selection. These plants were assessed for eight years at the Oceania Farm (FO) in Itagiba, Bahia, Brazil. The 13 microsatellite primers generated an average of 11.7 amplicons per locus, and based on them it was demonstrated that the 32 clones distribute themselves in groups apart from the nine clones used as controls. The 32 materials displayed significant differences in relation to the characters assessed in the field. Two criteria were formed from the classification of the most productive and resistant plants, and then used to select plants within the clusters. The selected plants displayed potential for the cacao improvement program, that they have a high production and high resistance to witches' broom.