Corn Starch: Quality and Quantity Improvement for Industrial Uses

Corn starch serves as food, feed, and a raw material for industrial use. Starch makes up most of the biomass of the corn hybrid and is the most important and main yield component in corn breeding programs. Starch is composed of two polymers, branched amylopectin and linear amylose, which normally constitute about 75% and 25% of the corn starch, respectively. Breeding for corn starch quality has become economically beneficial because of the development of niche markets for specialty grains. In addition, due to the increased demands of biofuel production, corn ethanol production is receiving more attention. Consequently, improving starch quantity has become one of the most important breeding objectives. This review will summarize the use of corn starch, and the genetics and breeding of grain quality and quantity for industrial applications.

Farmer response and financial feasibility of corn seed production in Southeast Sulawesi

To support the growth and development of corn in Southeast Sulawesi, information of farmer response and financial feasibility of corn seed production in South East Sulawesi are needed. The paper aims to determine farmers’ response and financial feasibility of corn seed production in Southeast Sulawesi, The results of this study are expected to be input for local governments in developing community-based seed breeders and can be useful for corn seedling businesses. The study was conducted in marc 2017 in Pangan Jaya Village, Lainea District, Konawe Selatan Regency, Southeast Sulawesi Province. The study was carried out by involving 20 farmers, 10 people for the production of corn seed production technology and 10 non-cooperator farmers who carried out according to the patterns and habits of farmers (feed corn production).. The data collected consists of (1) corn seed production data based on the results of corn seed reall production (2) farmer and non-breeder farm input data, consisting of expenditures for the purchase of production facilities and labor costs. The results of research were (1) Farmers’ response obtained, 83% of farmers gave a good perception of the breeding business of corn seeds. it means that corn breeding business is very likely to be cultivated and developed further. (2) Corn seed production business in Southeast Sulawesi is financially profitable and feasible to be developed with a B/C value of 2.15 and MBCR 4.4. These results indicate that the corn seed production business has good development prospects In order to support the continuous supply and fulfill of the need for quality corn seeds in Southeast Sulawesi, it is necessary to develop breeding of corn seeds, especially in areas of corn development centers. Market support is very much needed for the marketing of seed production. Market certainty will provide opportunities for the growth of new breeders, and will ensure the sustainability of corn seed breeding business at the farm level.

359 Intake and Growth Performance of Feedlot Lambs Fed Diets with Hi-a and Low-a Corn Cobs and Bermudagrass Hay

Hi-A™ corn is a unique type of lines and hybrids that were developed by the Texas A&M AgriLife Corn Breeding Program and have high anthocyanin and antioxidants. A completely randomized design trial was used to evaluated effects of Hi-A and low-A (regular) corn cobs and bermudagrass hay (BGH) in feedlot diets fed to female Rambouillet lambs (n = 10/treatment), with initial body weight (BW) of 30.7+1.2 kg, on dry matter intake (DMI), BW, average daily gain (ADG), and growth:feed ratio (G:F). After 14 days of adaptation, lambs were individually fed a total mixed ration with 80% concentrate and 20% of one of the roughages (Hi-A, low-A, or BGH) for 63 days. Hay was chopped, while cobs were ground using a hammermill with a 9.52-mm screen. Data were analyzed using repeated-measures ANOVA. The BW was not affected by the diet but increased (P < 0.001) during the trial. Diet did not influence the ADG. However, the ADG was lower (P < 0.001) in the d-42 (0.12 kg/d) than the rest of the trial (0.22 kg/d), after a period of constant high temperatures. The interaction diet vs. day affected (P < 0.05) DMI. In general, lambs increased (P < 0.05) DMI (g/d) and decreased (P < 0.05) relative DMI (%BW) in the final part of the trial, when the animals were getting closer to the harvesting date. Lambs had lower (P < 0.05) DMI of BGH diets than Hi-A diets from d-42 to d-63 and Low-A diets from d-49 to d-56. The G:F ratio was not affected by the diet but decreased (P < 0.05) from the middle to the end of the trial. Corn cobs are valuable as alternative roughage for feedlot lambs, with intake and growth performance comparable to BGH.

CO477, CO478, CO479, and CO480 inbred lines

CO477, CO478, CO479, and CO480 are mid- to late-season (75 – 81 days to flowering, CHU=1720–1855) corn (Zea mays L.) inbred lines with high stalk sugar levels. The level of sugar in the stalks are very high especially when grown as inbred lines. On average, the inbreds yield three times more sugar than their testcrosses. These inbred lines are the first to be developed and released for biofuel production, from the corn breeding program of Agriculture and Agri-Food Canada. Additionally, these inbred lines can be used for sugar and/or silage production. They have moderate to intermediate resistance to common rust, eyespot, northern corn leaf blight and fusarium stalk rot but are susceptible to gibberella ear rot.

Combining ability of corn inbreds – carriers of mutations Su1 and Su2 on the content of oleic acid glycerides

Aim. Evaluation of donors’ properties of corn inbreds - carriers of endospermic mutations su1 and su2 on the oleates content. Methods. A series of hybrids obtained in top- crosses of 10 inbreds of the common type with four testers – low-oleic and high-oleic inbreds of the common type and inbreds – carriers of the su1 and su2 mutations were analyzed. Oleates’s content was determined by the gas chromatographic method. Results. The highest effects of the general combining ability were shown by the inbreds obtained from high-oil synthetics and the inbreds - carriers the su1 and su2 mutations. Hybrids of low-oleic inbreds with the sources of su1 and su2 mutations had an increased content of oleates in comparison with maternal forms, and hybrids of high-oleic inbreds with the sources of these mutations inherited the oleates content in an intermediate type. In F2 hybrids from crosses of inbreds of the common type with the inbreds - carriers of the su1 and su2 mutations, transgressions were observed. Conclusions. The increased content of oleates in corn inbreds inbreds and hybrids is most likely controlled by oleate - coding loci of chromosome 4 and 6 linked to mutant genes su1 and su2. The carriers of these genes can be used as sources of increased oleate content in the corn breeding for oil quality. Key words: Zea mays L., endospermic mutants, oleates content, top-crosses

SELECTION OF GENETICALLY MARKED CORN LINES FOR ABILITY TO PARTHENOGENESIS

Haploids are the value initial materials in corn breeding. However, spontaneous frequency of their appearance is about 0.01%. Due to selection and task-oriented breeding, researchers of the Genetic Department and the Department of Genetic and Reproductive Biology of the Saratov StateUniversity obtained homozygotic lines predisposed to parthenogenesis, autonomous endospermogenesis, androgenesis, polyembriony: АТ-1; АТ-3 (АТ – Apomictic Tyrnova); АPО-3 (line obtained from matriclinous haploid of a line АТ-3). We developed new genetically marked corn lines АТТМ using lines АТ-1 and ТM. Estimation of haploidy frequency was conducted in the field and laboratory conditions. There were conducted caryological and cytoembryologic analyses of the newly developed lines.

Combining Ability Analysis in Sweet Corn (Zea Mays Saccharrata L.) Using Line by Tester Design

Aim The purpose of this study was to investigate the different combination of testcrosses for morphological and yield relating traits and to investigate general combining ability of the inbred lines. Materials and Methods This research was conducted at The University of Agriculture Peshawar, Pakistan during 2016. Line x-tester analysis was used to test general combining ability (GCA) effects of 24 S4 lines of sweet corn. Alpha lattice design with two replications and two checks was used during the experiment. Research data were recorded on various flowering, morphological and yield parameters. Results Highly significant variations were recorded among the testcrosses for the studied traits except anthesis silking interval (ASI), 100-kernel weight. Minimum days to tasseling (48-days) and silking (53.5-days) was exhibited by pop-syn-swt (9-4)×synthetic sweet. GCA effect was -2.14 for tasseling and -2.00 for silking. Maximum value (3.5-days) for ASI was recorded for Pop-synswt 1(8-3)×synthetic sweet, while GCA effect for ASI was -0.71. Lowest plant height (129.8 cm) was recorded for pop-syn-swt 1(3-3)×synthetic sweet, while GCA effect for plant height was observed to be -14.79. Maximum cob length (16.6 cm) was revealed by pop-syn-swt 1(12-2)×synthetic sweet. For cob length GCA effect of 1.01 was recorded. Maximum 100 kernel weight (31.3 g) was estimated for pop-syn-swt 1(2-1)×synthetic sweet. GCA effect of 1.85 was recorded for 100-kernel weight. Highest mean (7143.9 kg ha-1) for grain yield was recorded for pop-syn-swt 1(9-4)×synthetic sweet. GCA effect for grain yield was found to be 1370.93. Conclusion Generally a low GCA value, either positive or negative indicates that the mean of a parent does not largely vary from its offsprings. In contrast, high GCA value suggests that parent is either superior or inferior to the general mean and it has high heritability and less environmental effects. Based on the findings in this research, the above mentioned testcrosses can be included in future sweet corn breeding programs where early flowering and yield attributes is desired.

The Application of Metabolomics for the Study of Cereal Corn (Zea mays L.)

Corn (Zea mays L.) is an important cereal crop indigenous to the Americas, where its genetic biodiversity is still preserved, especially among native populations from Mesoamerica and South America. The use of metabolomics in corn has mainly focused on understanding the potential differences of corn metabolomes under different biotic and abiotic stresses or to evaluate the influence of genetic and environmental factors. The increase of diet-linked non-communicable diseases has increased the interest to optimize the content of bioactive secondary metabolites in current corn breeding programs to produce novel functional foods. This review provides perspectives on the role of metabolomics in the characterization of health-relevant metabolites in corn biodiversity and emphasizes the integration of metabolomics in breeding strategies targeting the enrichment of phenolic bioactive metabolites such as anthocyanins in corn kernels.

Draft Genome Sequence Resource for Phyllachora maydis—An Obligate Pathogen That Causes Tar Spot of Corn with Recent Economic Impacts in the United States

Phyllachora maydis is an important fungal pathogen that causes tar spot of corn and has led to significant yield loss in the United States and other countries. P. maydis is an obligate biotroph belonging to the Sordariomycetes class of Ascomycota. Due to the challenges posed by their obligate nature, there is no genome sequence available in the Phyllachora genus. P. maydis isolate PM01 was collected from a corn field in Indiana and the genome was determined by next-generation sequencing. The assembly size is 45.7 Mb, with 56.46% repetitive sequences. There are 5,992 protein-coding genes and 59 are predicted as effector proteins. This genome resource will increase our understanding of genomic features of P. maydis and will assist in studying the corn–P. maydis interaction and identifying potential resistant candidates for corn breeding programs.

Gwas and Genomic Selection For Increased Anthocyanin Content in Purple Corn

Purple corn offers an attractive source of economical natural anthocyanin-based colorant for use in foods and beverages. Yet to maximize the scalability and meet growing demands, both anthocyanin concentrations and agronomic performance must improve in purple corn varieties. We studied flux through the flavonoid biosynthesis pathway using GWAS data derived from a diverse purple corn landrace with anthocyanin-rich pericarp, Apache Red. Trends between flavonoid endpoints suggest that regulators of total flux into the pathway and regulators of partitioning within the pathway may both represent targets for maximizing anthocyanin content. A peak at the end of chromosome 1 near Aat1 (Anthocyanin acyltransferase1) was highly significant in all approaches taken to map anthocyanin flux, suggesting the structural modification of malonylation is required for maximal anthocyanin production. We also identified several candidate MATEs and H+ ATPases that could assist in the preferential transport of acylated anthocyanins into the vacuole. These and other candidates identified here suggest there is still much to learn about the regulation of anthocyanin biosynthesis in the pericarp of purple corn. The efficacy of genomic predictions in the population was also studied, yielding an accuracy of 0.71 with cross validation for total anthocyanin content with no improvement found when known anthocyanin regulators were added to the model. These data suggest that genomic selection could be employed effectively in a purple corn breeding program, and especially for a landrace improvement program.