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Despite the high proportion of maize grain in animal diets, the contribution made by maize phytochemicals is neglected. Tocols and their contribution to the vitamin E content of animal diets are one example, exacerbated by sparse information on the tocol bioaccessibility of commercial hybrids. In this study, the contents of individual and total tocols and their bioaccessibility were determined in the grain samples of 103 commercial hybrids using a standardized INFOGEST digestion procedure. In the studied hybrids, total tocol content ranged from 19.24 to 54.44 µg/g of dry matter. The contents of micellar α-, γ-, δ-tocopherols, γ-tocotrienol, and total tocols correlated positively with the corresponding contents in the grain samples of the studied hybrids. In contrast, a negative correlation was observed between the bioaccessibility of γ- tocopherol, α- and γ-tocotrienol, and total tocols, along with the corresponding contents in the grain of studied hybrids. The highest bioaccessibility was exhibited by γ-tocotrienol (532.77 g/kg), followed by δ-tocopherol (529.88 g/kg), γ-tocopherol (461.76 g/kg), α-tocopherol (406.49 g/kg), and α-tocotrienol (359.07 g/kg). Overall, there are significant differences in the content and bioaccessibility of total and individual tocols among commercial maize hybrids, allowing the selection of hybrids for animal production based not only on crude chemical composition but also on the content of phytochemicals. [ABSTRACT FROM AUTHOR]

Sweet corn, Zea mays Var. Saccharata is the youngest form of corn that arose after an accidental mutation in the common corn, and the Native Americans and Indian tribes began to cultivate it after becoming aware of the differences. The first registered variety of sweet corn was named Black Iroquois by European settlers in 1779. In the 19th century, white OP (open pollination) cultivars became popular in the United States. Two varieties of this type that are still cultivated and consumed are the Country Gentleman variety (with elongated and small seeds and irregular rows, also called Shoepeg corn) and the 'Stowell's Evergreen' variety. Scientific developments in the field of plant breeding, including the hybridization technology by inducing traits such as ripening at the same time and improving the quality of cobs and resistance to diseases, created tremendous changes in the production of sweet corn in the 20th century. This article with an overview of the successes achieved in creating new cultivars and improving the quality and marketability traits of sweet corn, its genetic differences from common corn, and the role of hybridization as one of the common tools of classical breeding to achieve superior genotype qualities are emphasized in sweet corn. Classification of sweet corn hybrid cultivars based on factors such as genes affecting carbohydrate metabolism and endosperm sugar percentage, planting time until harvest, seed color (yellow, white, pink, purple, and black), cob shape, and type of consumption (freshly eaten, Freezing, canning and exporting) forms another part of this article. Examining sweet corn breeding methods shows that despite the use of a number of specific techniques and theories, due to the different results of each method, the effect of external pollination, and the high perishability of the final product, Sweet corn breeding is very different in practice. The most important methods in sweet corn breeding have been reviewed in another part of this article. These methods include pedigree breeding, production of synthetic and composite masses, backcrossing and breeding with the help of molecular markers, as well as selection for some special traits such as edible quality, seed production, improved germination in Sh2 seeds, and resistance to pests and pathogens. In the final part, all kinds of sweet corn varieties, including commercial hybrids for fresh consumption and hybrids suitable for processing, have been introduced according to the genetic changes that have taken place in sweet corn cultivars since long ago.

Heterosis contributes greatly to crop production, but the genetic basis of heterosis is not fully understood. To identify heterotic loci (HLs) for grain yield, 12 yield traits were evaluated in four rice (Oryza sativa L.) mapping populations: one parental population of chromosome segment substitution lines derived from a cross between the japonica cultivar Nipponbare and indica cultivar 9311 and three connected test populations in either a homozygous 9311 genetic background or a heterozygous background. A total of 390 HLs were detected for the measured traits in two environments. The genetic bases of heterosis differed between the backcross and testcross populations. At least 10 HLs were confirmed in F1 hybrids between 9311 and near-isogenic lines, each of which carried a heterotic locus of interest in the same 9311 background. All 10 showed overdominant or dominant effects on grain yield and yield components. Among them, three were verified as being associated with yield heterosis and colocalized in the same regions as those containing previously reported heterosis-associated genes. Five HLs were identified to be promising candidate loci that could be used to achieve more than 15% yield heterosis in several commercial rice hybrids. These findings suggest the potential of indica or japonica introgression for increasing yield in hybrid rice breeding programs.

Commercial corn hybrids have a very high yield potential, with valuable features of adaptation to more or less favorable growing conditions. In the particular conditions of technology applied in a certain farm and in particular climatic conditions of the crop year, the production and the efficiency can approach more or less the yield potential of these hybrids, through their comparative testing being able to obtain information to determine the best assortment. Evaluation of the results obtained following the testing of three semi-early corn hybrids, from three different companies, at SC Semtop Group in Iaşi county, at sowing plots of 80,000 and 70,000 germinable grains/m², respectively, and under conditions of optimal assurance of the necessary irrigation water allowed to highlight the hybrids that behave best in the respective conditions. [ABSTRACT FROM AUTHOR]

Abstract Background The characterization of genetic diversity and population differentiation for maize inbred lines from breeding programs is of great value in assisting breeders in maintaining and potentially increasing the rate of genetic gain. In our study, we characterized a set of 187 tropical maize inbred lines from the public breeding program of the Universidade Federal de Viçosa (UFV) in Brazil based on 18 agronomic traits and 3,083 single nucleotide polymorphisms (SNP) markers to evaluate whether this set of inbred lines represents a panel of tropical maize inbred lines for association mapping analysis and investigate the population structure and patterns of relationships among the inbred lines from UFV for better exploitation in our maize breeding program. Results Our results showed that there was large phenotypic and genotypic variation in the set of tropical maize inbred lines from the UFV maize breeding program. We also found high genetic diversity (GD = 0.34) and low pairwise kinship coefficients among the maize inbred lines (only approximately 4.00 % of the pairwise relative kinship was above 0.50) in the set of inbred lines. The LD decay distance over all ten chromosomes in the entire set of maize lines with r 2 = 0.1 was 276,237 kb. Concerning the population structure, our results from the model-based STRUCTURE and principal component analysis methods distinguished the inbred lines into three subpopulations, with high consistency maintained between both results. Additionally, the clustering analysis based on phenotypic and molecular data grouped the inbred lines into 14 and 22 genetic divergence clusters, respectively. Conclusions Our results indicate that the set of tropical maize inbred lines from UFV maize breeding programs can comprise a panel of tropical maize inbred lines suitable for a genome-wide association study to dissect the variation of complex quantitative traits in maize, mainly in tropical environments. In addition, our results will be very useful for assisting us in the assignment of heterotic groups and the selection of the best parental combinations for new breeding crosses, mapping populations, mapping synthetic populations, guiding crosses that target highly heterotic and yielding hybrids, and predicting untested hybrids in the public breeding program UFV.

Background: The characterization of genetic diversity and population differentiation for maize inbred lines from breeding programs is of great value in assisting breeders in maintaining and potentially increasing the rate of genetic gain. In our study, we characterized a set of 187 tropical maize inbred lines from the public breeding program of the Universidade Federal de Viçosa (UFV) in Brazil based on 18 agronomic traits and 3,083 single nucleotide polymorphisms (SNP) markers to evaluate whether this set of inbred lines represents a panel of tropical maize inbred lines for association mapping analysis and investigate the population structure and patterns of relationships among the inbred lines from UFV for better exploitation in our maize breeding program. Results: Our results showed that there was large phenotypic and genotypic variation in the set of tropical maize inbred lines from the UFV maize breeding program. We also found high genetic diversity (GD = 0.34) and low pairwise kinship coefficients among the maize inbred lines (only approximately 4.00 % of the pairwise relative kinship was above 0.50) in the set of inbred lines. The LD decay distance over all ten chromosomes in the entire set of maize lines with r2 = 0.1 was 276,237 kb. Concerning the population structure, our results from the model-based STRUCTURE and principal component analysis methods distinguished the inbred lines into three subpopulations, with high consistency maintained between both results. Additionally, the clustering analysis based on phenotypic and molecular data grouped the inbred lines into 14 and 22 genetic divergence clusters, respectively. Conclusions: Our results indicate that the set of tropical maize inbred lines from UFV maize breeding programs can comprise a panel of tropical maize inbred lines suitable for a genome-wide association study to dissect the variation of complex quantitative traits in maize, mainly in tropical environments. In addition, our results will be very useful for assisting us in the assignment of heterotic groups and the selection of the best parental combinations for new breeding crosses, mapping populations, mapping synthetic populations, guiding crosses that target highly heterotic and yielding hybrids, and predicting untested hybrids in the public breeding program UFV. [ABSTRACT FROM AUTHOR]

Maize dwarf mosaic (MDM) is one of the most important virus diseases of maize worldwide. Caused by the potyviruses maize dwarf mosaic virus (MDMV) or sugarcane mosaic virus (SCMV), MDM can cause up to 90% yield loss in susceptible hybrids. One of the most effective management strategies for MDM is growing potyvirus-resistant corn varieties. However, yield impacts associated with MDM and the corresponding efficacy of genetic resistance present in modern United States commercial hybrid lines is uncharacterized. In this study, we evaluated the disease response of 78 commercial hybrids to MDMV and SCMV and quantified yield losses associated with infection over multiple trials. We determined that while 97% of the hybrids tested were resistant to MDMV, 100% were susceptible to SCMV, with mean disease incidence per line averaging between 45 and 78% across six trial years. Despite only one hybrid displaying visible mosaic symptoms when inoculated with MDMV, MDMV reduced average yields by approximately 5% across all hybrids compared with the mock-inoculated treatment. The yield impact of SCMV was more severe, reducing average yields by 10% across replicated experiments. These results indicate that while most commercial hybrids are resistant to MDMV, possibly due to the presence of the major Scmv1 resistance locus on chromosome 6, additional potyvirus resistance genes are needed to manage SCMV-induced MDM. Pyramiding resistance loci, such as Scmv2 on chromosome 3 or Scmv3 on chromosome 10 in addition to Scmv1 , could be an effective strategy to mitigate the yield impact of MDM disease., Competing Interests: The author(s) declare no conflict of interest.

Grown in water-limited environments, sorghum (Sorghum bicolor (L.) Moench) is often exposed to water deficits of varying extent and timing. One of the impacts of water stress on sorghum production is lodging; however, there has been no published study quantifying the temporal and spatial frequency and severity of lodging in grain sorghum in Australia. In this study, we investigated the frequency and severity of lodging, using a dataset of 83 advanced yield-testing trials of the sorghum pre-breeding program grown in the seven major sorghum-production environments in Australia over 14 summer growing seasons. Lodging occurred in most production regions but with varying frequency and severity. Lodging was significantly greater in regions that were more prone to water stress (e.g. Central Highlands in Queensland) and significantly lower in regions that were less likely to suffer from water stress (e.g. Liverpool Plains in northern New South Wale) compared with the overall average across regions. The severity of lodging also varied across regions, with the most severe lodging (>20%) occurring in Central Highlands and Western Downs in Queensland. In addition, seasonal patterns of lodging frequency and severity were also observed. Over the 14 growing seasons, the frequency of lodging varied from 0% to 100%, with the most severe lodging (>20%) observed in 2005, 2016 and 2017. The Southern Oscillation Index explained 29% of the seasonal variation in lodging frequency. The findings of this study clearly support a link between lodging incidence and water stress across regions and seasons. Our data also showed that although there was a substantial turnover of commercial hybrids during the period of this study, the level of resistance to lodging appeared not to have improved. It is possible that this is due to plant breeders trading off improvements in lodging resistance to increase grain yield. Lodging often occurs in sorghum in Australia owing to water limitation; however, no published study has quantified lodging occurrence. Our study revealed that lodging frequency and severity varied geographically and seasonally, that lodging frequency was associated with the SOI, and that lodging resistance has not improved in commercial hybrids over 14 years. This is the first study to document lodging occurrence in Australia and provides a more thorough understanding of the causes of this potentially devastating and intractable trait. [ABSTRACT FROM AUTHOR]

The tomato crop has social, food, and economic importance both in Brazil and internationally for generating high employment opportunities in the productive sector and offering high nutritional value of the fruits. Given the importance of this tomato culture, there is a constant search for improved varieties that meet the needs of producers in the processing industry. The objective of this study was to characterize strains of the industrial tomato in the absorption of macronutrients and micronutrients, in level of chlorophyll content in leaves, in productivity, and in uniformity of maturation fruits. The experiment was conducted in 2014 in the experimental area of the Federal University of Goiás in Goiânia. The design was a randomized block with 25 treatments (22 lines and three commercial hybrids) and four replications. We evaluated the chlorophyll content in leaves, macronutrient content, foliar macro and micronutrient content, fruit yield, and uniformity of maturation. The lineages CVR 1, CVR 3, CVR4, CVR 5, CVR21, and CVR 22 have high productivity, as well as being uniform in maturation. The lineages CVR 2, CVR 5, CVR 7, CVR 8, CVR 9, CVR 10, CVR 11, CVR 12, CVR 13, CVR 14, CVR 15, CVR 16, CVR 17, CVR 18, CVR 19 and CVR 20 are uniform in maturation. The lines have different potentials regarding the absorption of P, K, Ca, Mg and Zn. There is a positive correlation between the chlorophyll content and the amount of nitrogen present in the leaves.

The objectives of this work were to study the genetic control of grain yield (GY) and nitrogen (N) use efficiency (NUE, grain yield/N applied) and its primary components, N uptake efficiency (NUpE, N uptake/N applied) and N utilization efficiency (NUtE, grain yield/N uptake), in maize grown in environments with high and low N availability. Experiments with 31 maize genotypes (28 hybrid crosses and three controls) were carried out in soils with high and low N rates, in the southeast of the state of Minas Gerais, Brazil. There was a reduction of 23.2% in average GY for maize grown in soil with low N, in comparison to that obtained with high N. There were 26.5, 199 and 400% increases in NUtE, NUpE, and NUE, respectively, for maize grown with low N. The general combining ability (GCA) and specific combining ability (SCA) were significant for GY, NUE and NUpE for maize grown in high N soil. Only GCA was significant for NUpE for maize grown in low N soil. The GCA and SCA for NUtE were not significant in either environment. Additive and non-additive genetic effects are responsible for the genetic control of NUE and GY for maize grown in soils with high N availability, although additive effects are more important.O objetivo deste trabalho foi estudar o controle genético da produtividade de grãos (PG) e da eficiência no uso de nitrogênio (EUN, produção de grãos/N aplicado) e seus componentes primários - eficiência de absorção (EAbN, N absorvido/N aplicado) e utilização (EUtN, produção de grãos/N absorvido) -, em milho cultivado em ambientes com alta e baixa disponibilidade de nitrogênio. Trinta e um genótipos de milho (28 cruzamentos entre híbridos comerciais e três testemunhas) foram avaliados em solos com alta e baixa doses de aplicação de N. Houve redução de 23,2% na média de PG em milho cultivado em solo com baixo teor de N, em relação à obtida com alto N. Com baixo teor de N no solo, observaram-se aumentos de 26,5, 199 e 400% em EUtN, EAbN, e EUN, respectivamente. Em milho cultivado em solo com alto teor de N, as capacidades geral (CGC) e específica (CEC) de combinação foram significativas em PG, EUN e EAbN. Em milho de solos com baixo teor de N, apenas a CGC, na EAbN, foi significativa. A CGC e a CEC não foram significativas, em nenhum dos ambientes, na EUtN. Efeitos genéticos aditivos e não aditivos são responsáveis pelo controle genético da EUN e PG, em milho cultivado em solos com elevada disponibilidade de N, mas os efeitos aditivos são mais importantes.

O melhoramento genético de suínos levou ao surgimento de diversas linhagens suínas que apresentam elevada capacidade de desenvolvimento de massa muscular. Entretanto, pouco se sabe cientificamente sobre a morfologia de órgãos destes animais, conhecimento que ajuda a elucidar características relacionadas ao desempenho zootécnico como ganho de peso e conversão alimentar em carne magra. Objetivou-se, assim, comparar a morfologia dos órgãos digestivos e não-digestivos de suínos de linhagens modernas ao final das fases de Crescimentos Ie II, Terminação e Pós-terminação. O peso dos órgãos em relação ao peso vivo diminuiu significativamente (p < 0,01) com o desenvolvimento corporal. A morfologia dos órgãos digestivos diferiu significativamente (p < 0,06) entre as linhagens, demonstrando diferentes capacidades digestivas e, possivelmente, consumo e eficiência alimentares das linhagens utilizadas. Foi observada também diferença significativa (p < 0,06) quanto ao comprimento dointestino delgado, o que pode ser indicativo para maior desenvolvimento dos tecidos corporais devido a maior área de exposição dos alimentos às células absortivas intestinais. Portanto, faz-se necessário o conhecimento detalhado da morfologia dos órgãos das linhagens, uma vez que estas características contribuem para o desempenho zootécnico dos animais.The genetic market makes use of various modern swine genotypes that present high capacity for muscular mass development. These genetic lines have been used in swine production without existing scientificinformation about morphology, knowledge that can elucidate factors related to growth performance, such as weight gain and food conversion in lean meat yield. The aim of this experiment was to compare the morphology of digestive and non-digestive organs of moderngenotypes. At the end of the phases: Growing I, Growing II, Finishing and Post-finishing, the pigs were slaughtered and the organs were weighed. The weight of the organs decreased (p < 0.01) with body development, in agreement with the biological growth of the animals. The morphology of the digestive organs were different (p < 0.06) among lineages, which showed that differences can exist, mainly regarding digestive capacity and, possibly, food intake and efficiency. The length of the small intestine was different (p < 0.06) among lines, which can be an indicative of increased body development due to an extended food exposition area to intestinalcells. The scientific knowledge of swine lines morphology is important because this information can contribute to animal growth performance.

Purpose of investigation was to group test environments in les number of target environments on the basis of specific interactions of genotypes. Fifteen commercial maize hybrids were investigated. Trials were conducted in six locations during two years. Two hybrids were detected as carriers of maximal grain yield in target environments. By use of information from GxE interaction, narrow adaptability for maize was utilized.

Immature sunflower ( Helianthus annuus L.) zygotic embryos belonging to R and B sunflower lines were treated with ultra sound and gamma rays before planting in an embryo culture medium. In those circumstances new mutant lines with the altered architecture, increased oil content, 1000-seed weight, number of seed per head, as well as seed yield were developed. Some mutant lines showed very good combining abilities. Line 12004 R (developed trough Embryo culture method in immature zygotic embryos in combination with gamma irradiation at dose 8 Gy), paternal component of hybrid Goryanin, line 12002 R (developed trough Embryo culture method in immature zygotic embryos in combination with gamma irradiation at dose 8 Gy), paternal component of the commercial hybrid Rada and line 12003 R (developed trough Embryo cluture method in immature zygotic embryos in combination with ultra sound at dose 25.5 W/cm2 for 1 min) and paternal component of the commercial hybrid Yana were realized. Hybrid Goryanin considerably exceeded the average standard (the Bulgarian commercial hybrids Mercury, Perfect and S-205) by seed yield with 15.2%. Hybrid Rada considerably exceeded the average standard of seed yield by 2.3-7.7% (in relation to Bulgarian commercial hybrid Albena and French commercial hybrid Diabolo). The vegetation period was 115 days. The hybrid Yana considerably exceeded the average standard of seed yield by 7.6%-14.4% (in relation to Bulgarian commercial hybrid Perfect and French commercial hybrid Diabolo). Its vegetation period is 110 days. The hybrids Rada and Yana possess the immunity to the parasite Orobanche cumana race G, immunity to Plasmopara helianhi-races 300, 330, 700 and 731, immunity to Phomopsis and Macrophomina, immunity to Sclerotinia sclerotiorum (root form) and tolerance to Phoma. [ABSTRACT FROM AUTHOR]

Genetic diversity within the Saccharum spontaneum germplasm and commercial cultivars from sub tropical part of India has not been extensively examined with molecular markers as it was quite difficult to recognize through morphological and physiological characters. The similarity coefficient ranging from 0.347 (CoS96268 and Calcutta) to 0.865 (CoS 95255 and CoS 767) revealed that there was sympatric relationship between variety × variety and allopatric (0.347) relationship between variety × species. This has also confirmed by the higher variation observed for quality traits in S. spontaneum (71.4 %) than in commercial cultivars (23.11 %).These diverse genotypes had not been extensively utilized in the development of other sugarcane cultivars; they can be used as progenitors for the creation of cultivars with a wider genetic base. [ABSTRACT FROM AUTHOR]

This work was carried out with the aim of linking growth and quality variables of orange flint maize hybrids to use in brewing industry. The experiment was settled with five commercial maize hybrids in a randomised complete block design with four replications in random plots of 6 lines and 20 m long. The experiments were conducted without any limiting factor such as water and nutrients. The variables measured were dry matter content, area index, radiation interception, yield and quality, floating rate, test weight, and relation between milling and fat. Yield obtained for the different hybrids were 771 and 982 g m-2 (p <0.0001). Also, association between the relation source-posflowering destination and two quality variables, the flotation index and the weight test. [ABSTRACT FROM AUTHOR]

Abstract: Commercial hybrid maize varieties are often used to extract new inbred lines in hybrid breeding programs. Seven commercial hybrid maize varieties were crossed in a diallel design, and the resulting hybrids and selfed progeny were evaluated for yield and adaptability grown in six locations in Thailand. The parental varieties were analyzed with a set of 64 Simple Sequence Repeat (SSR) loci, spanning all 10 chromosomes. The average number of alleles per SSR locus was 4.98 with a range of 2–11. The polymorphic information content (PIC) varied from 0.24 to 0.89, with an average of 0.69. Using SSR-based genetic distance (GD), an UPGMA dendrogram showed seven field corn varieties classified into three distinct groups. Troyer''s genetic distance (TGD) calculated from yield data, which is a function of inbreeding depression, varied from 0.493 to 1.015 between different parental combinations. A significant positive correlation was found between the GD and TGD across the six locations (0.66**). The GD correlated positively with specific combining ability (SCA) as well across all locations (r =0.76**) heterosis was significant for grain yield and SCA, accounting for 47% of the sum of the square among entries. Therefore, we suggest that broad base populations derived from each of the distinct groups can be formed using combined criteria of SSR-based GD, TGD, grain yield, GCA and SCA. [Copyright &y& Elsevier]