Types Of Maize Research Articles

Variables related to microwave heating-toasting time and water migration assessment with kernel size approaches of specialty maize types.

Three main maize types with specialty kernels are used to make ready-to-eat maize by traditional toasting, and microwave toasting may be an innovative application. However, little is known of the toasting process of these Andean maize types. Therefore, the present study aimed to explore the behavior of a broad scope of variables in these maize types. The kernels were packed in sealed paper envelopes and subjected to six microwave heating-toasting times from 0 to 390 s. Subsequently, with actual kernel size approaches, water content (WC), water ratio (WR), and water loss (WL) were analyzed. In addition to WC, WR, and WL, the surface area (S), volume (V), and geometric mean diameter (GMD) behaved like time-related variables with a high correlation depending on the maize types and kernel dimensions. Thus, the WC, WR, and WL third-order polynomial regression curves computed with the spatial (S/V)2 and distance (GMD/2)2 approaches indicated the water variation at each microwave heating-toasting time with a clear difference among maize types a0, a1, and a2. Regarding their exchange profiles without and with the spatial (S/V)2 approach, the maximum rates showed significant differences between maize types and WC and WL. Likewise, the maximum rates displayed significant differences between the spatial (S/V)2 and distance (GMD/2)2 approaches, revealing a notable lack of consistency with the distance (GMD/2)2 approach. The kernel size approaches revealed that water migration rates depended on differences in maize types. Such basic information represents the first insight into more physical-based models of water diffusion during raw microwave maize heating-toasting. © 2022 Society of Chemical Industry.

Modeling of the microwave heating-toasting time-related variables and characterization of non-isothermal rheological properties of floury and sweet specialty maize kernels

The three primary floury and sweet maize types, with specialty kernels to make entire ready-to-eat maize, and packed in sealable paper envelopes, were the experimental units (150 g of raw kernels) to model the effect of the microwave heating-toasting (2450 MHz microwave oven, 492 W, times 0, 78, 156, 234, 312, and 390 s) on time-related variables and characterize the non-isothermal rheological properties. Pauses every 60 s for a rapid manual shaking compensated for non-uniformity of microwave volumetric heating. Surface color difference (ΔE*), internal porosity, milling average particle size, and flour hydration properties displayed curves adequately described by simple and nonlinear regression models. The milling particle size, hydration properties, and rheological parameters illustrated floury and sweet kernel differences ascribed to their proximal composition. Onset and peak temperatures depended on maize types and showed a little variation attributed to microwave heating-toasting times. The elastic/viscous modulus ratio increased in floury maize. It decreased in sweet maize, unveiling rheological differences associated with microwave heating-toasting time effect on the contrasting structure of floury and sweet specialty Andean maize kernels used for toasting.

Determination of Vitamin Contents of Maize (Zea mays L) Produced and Stocked from Rural Conditions in Cote D’ivoire

Aims: Maize is prized for its richness in nutrient compounds. Despite its socio-economic importance, maize faces a quality problem that is sometimes very delicate. Indeed, maize during different production, post-harvest processing, storage and transport conditions is exposed to bio-aggressors that can alter the quality of this cereal. With this in mind, this study was conducted to determinate the vitamins contents of maize produced and stored in five maize-producing regions of Côte d’Ivoire.
 Study Design: A total of 1 500 samples of maize as grains, epis and spathes were collected at rate of 500 samples by region (Gbêkê, Poro, Hambol, Indénié-Djuablin and Gontougo) and sent to the laboratory for analysis of the vitamin contents.
 Place and Duration of Study: This study was carried out during March 2016 to January 2017. Then, the analyses of the collected sample took place at the Biotechnology, Agriculture and Valorisation of Biological Ressources Laboratory of the Félix Houphouët-Boigny’s University, Abidjan.
 Methodology: Vitamins determination was carried by High Performance Liquid Chromatography. A total of twelve vitamins were evaluated namely 9 water-soluble vitamins (thiamin, riboflavin, niacin, choline, pantothenic acid, pyridoxine, biotin, folic acid and cobalamin) and 3 fat-soluble vitamins (β-carotene, vitamin E and K).
 Results: Results show a significant difference between vitamins contents of the different maize forms and regions. The mean values ranged from 0.09 ± 0.04 to 557.24 ± 10.97 mg / kg for water-soluble vitamins and from 0.31±0.25 to 4.20±1.00 mg / kg for fat-soluble vitamins. Choline was the most abundant of the water-soluble vitamins while β-carotene and vitamin E were the most abundant of the fat-soluble vitamins. Maize grains and epis had the highest levels of these vitamins all of the regions. Maize spathes samples, especially those from Indénié-Djuablin and Gontougo, showed the lowest concentrations.
 Conclusion: A significant variability from one region to another can be noticed at level of vitamins regardless the type of maize. Maize vitamin contents seem to be related to maize form (grains, epis, spathes), maize variety, agronomic practices, post-harvest treatments and storage structure.

Negligible Impact of Drought-Resistant Genetically Modified Maize on Arthropod Community Structure Observed in a 2-Year Field Investigation.

Dehydration-responsive element-binding (DREB) transcription factors regulate diverse processes during plant development. Here, a 2-year field study was conducted to assess the potential effects of DREB-genetically modified maize (GM1) on arthropod species and ecological communities. Arthropod abundance, diversity, and community composition in GM1 and its non-transformed counterpart maize variety, Chang 7-2, were compared using whole plant inspection, pitfall trap, and suction sampler methods. Based on Shannon–Wiener diversity, Simpson’s diversity, Pielou’s indexes, number of species, and total number of individuals, GM1 had a negligible effect on arthropod abundance and diversity. Redundancy analysis indicated that the composition of arthropod community was not associated with maize type in the three investigation methods, while it exhibited significant correlation with year and sampling time in whole plant inspection and suction sample methods, and distinctly correlated with sampling time in the pitfall trap method. Nonmetric multidimensional scaling analysis of variable factors in the three investigation methods showed that sampling time, rather than maize type or year, was closely related to the composition of arthropod community in the field. Our results provide direct evidence to support that DREB-GM maize had negligible effects on arthropods in the Jilin Province under natural conditions.

Influence of Endosperm Starch Composition on Maize Response to Fusarium temperatum Scaufl. & Munaut

Fusarium temperatum Scaufl. & Munaut is a newly described taxon belonging to the Fusarium fujikuroi species complex (FFSC) and a frequent causative factor of maize ear rot. The aim of the present study was to determine the responses to the disease in maize populations differing in endosperm features that were classified to flint, dent, and a group of plants with intermediate kernel characteristics. In inoculation studies, substantial variation of host response to the fungus was found among the tested maize types. The dent-type kernels contained significantly less amylose (28.27%) and exhibited significantly higher rates of infection (IFER = 2.10) and contamination by beauvericin (7.40 mg kg−1) than plants of the flint maize subpopulation. The study documents a significant positive correlation between the Fusarium ear rot intensity (IFER) and ergosterol content (the R value ranged from 0.396 in 2015 to 0.735 in 2018) and between IFER and the presence of beauvericin (the R value ranged from 0.364 in 2015 to 0.785 in 2017). The negative correlation between (IFER) and amylose content (ranging from R = −0.303 to R= −0.180) stresses the role of the endosperm starch composition in the kernel resistance to Fusarium ear rot. The conducted study indicated that the risk of kernel infection and contamination with fungal metabolites (beauvericin and ergosterol) was associated with the maize type kernels.

Optimizing Food and Feed in Maize–Livestock Systems in Northern Ghana: The Effect of Maize Leaf Stripping on Grain Yield and Leaf Fodder Quality

Access to feed for livestock during the cropping season is a constraint to the smallholder crop–livestock farming system in northern Ghana due to backyard farming. A two-year (2017–2018) study was conducted to determine the effect of leaf stripping on yield and feed quality in maize–livestock farming systems in the Northern, Upper East, and Upper West regions of Ghana. A factorial treatment combination of three maize-maturity types (extra-early: Abontem, early: Omankwa, and medium: Obatanpa) and three leaf stripping methods (control, leaf stripping at 50% tasseling, and leaf stripping at 50% silking of maize) were laid out in a strip-plot design with four replications per region. Stripped leaf biomass, grain yield, stover, cob size, and nutritional quality of stripped maize leaf were measured. The stripped leaf biomass, stover, and cob width of Obatanpa increased significantly relative to the other maize types in the Northern and the Upper West regions. Abontem recorded a higher (p < 0.01) grain yield than that of the other maize types in the Upper East Region. Leaf stripping had no significant effect on the grain yield and the crude protein (CP) content of maize leaf. The CP of the maize leaf (93–100 g/kg) was above the minimum CP requirement of a quality feed for body weight maintenance of ruminants. This suggests that smallholder maize–livestock farmers could strip maize leaves at either tasseling or silking to feed their livestock during the cropping season in northern Ghana and similar agro-ecological zones in West Africa.

Nixtamal techniques for different maize races prepared as tortillas and tostadas by women of Chiapas, Mexico

Nixtamalization, which means cooking maize in alkaline water, is the central technique for the culinary use of maize in Mexico and Central America. Without this procedure, relying on maize as the basic starch staple is inadequate because of nutriment deficiencies. Mexico has more than 50 principal racial types of maize, and these differ in grain qualities that can require the adjustment of the nixtamalization process. Properties such as hardness and grain composition influence nixtamalization because they are related to the absorption of water that occurs during cooking and steeping. Some maize preparations, like tortillas and tostadas, can also require the adjustment of nixtamalization to obtain a high-quality foodstuff. We studied how women in three regions of the state of Chiapas, which differ in the prevalent maize race available, prepare their nixtamal and whether they make changes according to the type of food they prepare. Interviews of 30 women follow the measure of relevant variables when the women prepared nixtamal. We found that nixtamalization is adjusted for different grain hardnesses and for environmental conditions. Variations were found in the cooking time of the nixtamal, in the amount of time the nixtamal was steeped, and in a special process of double boiling of the nixtamal performed by some women for tostadas. Women that specialize in production for the market have developed variations preferred by consumers. As practiced by women in Chiapas, nixtamalization is a flexible technique that is adjusted for maize type and for food preparations.

Waxy allele diversity in waxy maize landraces of Yunnan Province, China

Waxy maize is one of the main fresh-eating maize types, and a mutation of the waxy gene causes the waxy character of maize grains. China is rich in waxy maize landraces, and Yunnan and its surrounding areas, are the place of origin and genetic diversity center of Chinese waxy maize. The six known waxy alleles of Chinese waxy maize are wx-D7, wx-D10, wx-Cin4, wx-124, wx-Reina, and wx-Xuanwei. The mutation sites of these alleles all occur in the coding region of the waxy gene, however, the mechanism by which the waxy characteristic is caused by the mutation in the regulatory region has only been reported rarely in maize. In this study, 405 waxy maize landraces from Yunnan were used as materials to identify the insertion and deletion of a large sequence fragment in the upstream ∼3.5 kb regulatory region of the waxy gene by molecular marker detection. Three different waxy alleles were identifed in this study: wx-PIF/Harbinger, wx-hAT and wxElote2. These three types of mutations all represented transposons inserted into the regulatory region of the waxy gene. Wx-PIF/Harbinger was a 304-bp MITE class transposon insertion belonging to the PIF/Harbinger family, while wx-hAT was a 560-bp MITE class transposon insertion belonging to the hAT family, and wx-Elote2 was a 6 560-bp LTR-like transposon insertion. In this study, the alleles were identifed for more than 70% of the waxy maize landraces in Yunnan, which provids a basis for the utilization of these waxy maize landraces.

Nutrient Content of Traditional Foods Prepared from Yellow Maize (<i>Zea mays</i> L.) Varieties in Ethiopia

Maize (<i>Zea mays</i> L.) is one of the most important cereal grains for both human food and livestock feed. Ethiopia is among the major maize producers in Africa and ranked fourth next to South Africa, Nigeria and Egypt. Maize production takes significant share of cereals and grain in any production year. The aim of this study was to evaluate the nutrient availability of traditional foods prepared from maize varieties (BHQPY545, BH661, Melkasa-1Q and Melkasa-7). HPLC and AAS methods were used to determine beta-carotene and menial contents, respectively. AOAC methods were used to analyze the proximate composition. The results showed that there was a significant difference (p<0.05) in most proximate compositions of the 4 maize varieties. Total carbohydrate between maize varieties ranged from 72.39 to 74.08%, crude fiber (2.19 to 2.23%), crude protein (6.61 to 10.52%), crude fat (3.72 to 5.19%), ash (1.07 to 1.34%), and moisture (9.91 to 12.04%). The products of maize varieties (stiff porridge and flat bread) did not have any significant effect on the crude fiber, crude protein, and ash. Beta-carotene content in BHQMY545 maize was found to be 2.33±0.12, 2.72 ± 0.06 and 2.46±0.51µg/g for raw, stiff porridge and unleavened flat bread, respectively. In four maize types, there was a significant difference (p<0.05) in crude fat, calcium, potassium. In general, there is no need to select processing methods because the nutritional makeup of maize types retains better after processing.

Maize Types from the Andean Region with Specialty Kernels to Make Whole Ready-to-Eat Maize by Toasting and Future Frontiers

Maize Types from the Andean Region with Specialty Kernels to Make Whole Ready-to-Eat Maize by Toasting and Future Frontiers

Comparison of Polycyclic Aromatic Hydrocarbons, Pahs Concentration Levels in Types of Beans and Maize from Markets in South East Nigeria

Polycyclic aromatic hydrocarbons, PAHs are carcinogenic, mutagenic and persistent organic compounds commonly generated from incomplete combustion of organic matters. Beans,<i> Phaseolus vulgaris</i> and maize,<i> Zea mays</i> form part of staple foods commonly consumed and are highly rich in protein and carbohydrate respectively. This study compared the concentration levels of the sixteen priority PAHs in different types of beans (Potasikum, white iron, brown iron, Gausau and Nija red) and maize (white, yellow and pop corn) obtained from various markets in south east Nigeria. The purchased beans and maize samples were picked, ground and extraction was by sonication with a solvent mixture of dichloromethane and hexane in the ratio of 3:1. The determination of PAHs was by gas chromatography coupled with flame ionization detector, GC-FID. The result showed that the PAHs concentration levels (× 10^-2 µg/kg) of lower molecular weight PAHs, LMW detected in the analyzed beans samples ranged from 8.842±4.743 to 12.590±8.068 in white iron beans and brown iron beans respectively with percentages of 41.09% and 44.90% and 5.998±4.725 to 9.385±11.339 in pop and white corn respectively at 25.58% and 34.46%. While the high molecular weight, HMW PAHs concentration levels (× 10^-2 µg/kg) varied from 12.673±5.554 in white iron beans to 16.998±3.129 in Nija red beans at 58.88% and 63.95% and from 17.84±11.768 in pop maize to 18.153±10.421 in yellow maize at 74.83% and 67.43% respectively. The probable carcinogenic PAH8 concentrations detected varied from (8.875±2.725 to 11.796±3.018) × 10^-2 µg/kg in white iron beans and brown iron beans respectively and from (10.82±6.183 to 13.573±8.789) × 10^-2 µg/kg in pop and yellow maize respectively.. Diagnostic ratio calculated showed fuel combustion to be the main source of emission. The sixteen priority PAHs were detected in all the analyzed samples at a very low concentration levels, lower than the permissible limit of 1.0 µg/kg established by EFSA for cereals and cereal based products. Hence these (PAHs) can at a long time accumulation in the body be very harmful. There is need to establish a permissible limit of PAHs in beans and other legume grains by either European Food Safety Authority, EFSA or other regulatory bodies.

EMERGING IMPACT OF Spodoptera frugiperda (FALL ARMYWORM) ON MAIZE IN NEPAL AND ITS CONTROL MEASURES

Spodoptera frugiperda is a migratory pest that infects maize and is noted for its high likelihood of dispersing quickly. It was originally discovered in central and western Africa in 2016, and Nepal’s first incidence of FAW was discovered in a maize crop on May 9th, 2019. S. frugiperda severely harmed maize harvests across the country in 2020, at a greater rate than the previous year. The cause and impact of FAW in Nepal have been identified as Nepal’s open border and a lack of seed quarantine control for late-maturing hybrids and late planting maize types. By heavily feeding on leaves, younger larvae inflict significant crop damage. Integrated pest management (IPM) techniques, which combine physical and mechanical, cultural, botanical, biological, and chemical methods, have been found to be effective in controlling and monitoring FAW in Nepal. As a result, the focus of this research is on the developing implications of FAW in Nepal, as well as control and prevention approaches to reduce the loss caused by FAW through appropriate management alternatives.

The influences of lime and irrigation water on arsenic accumulation of rice, maize and mungbean in the nethouse condition

This research found the great hold of liming, soils and irrigation water on the arsenic (As) accumulation of rice, maize and mung bean in the nethouse research. Two greenhouse experiments had various plant types of rice, maize and mung bean with two soils inside and outside the dyke, two irrigated waters of 0.0 and 200 ?g As/L and three different lime ratios (0, 7.0 and 9.0 tons CaO/ha). The whole treatments were twenty one (12 treatments of experiment 1 and 9 of experiment 2) with 4 repetitions. The results of this study showed that the lime application raised both soil pH and crop yield. The arsenic (As) absorption of plant bodies in stems and seeds inside the dyke increased from 67.8 to 68.3% higher than those outside the dyke, respectively. The arsenic contents of stems and seeds with the treatments of 200 ?g As/L irrigation water were higher from 81.5 to 89.4% than that of non As irrigation water, respectively. The lime supplementation of 7.0 and 9.0 tons CaO per ha reduced the As accumulation of stems and seeds of rice, maize and mung bean was lower than the one without lime supplement from 38.6 (stems) and 54.5 (seeds). Mung bean absorbed the highest As, followed by rice and maize with the lowest As value. However, the lime supplementation of 9.0 tons CaO/ha had so high soil pH of soil that restricted the growth and yield of crops. More different lime concentrations need to search for more new details and new discovery of positive effects of this research.

Regionalizing crop types to enhance global ecosystem modeling of maize production

Improving the prediction of crop production is critical for strategy development associated with global food security, particularly as the climate continues to change. Process-based ecosystem models are increasingly used for simulating global agricultural production. However, such simulations often use a single crop variety in global assessments, implying that major crops are identical across all regions of the world. To address this limitation, we applied a Bayesian approach to calibrate regional types of maize (Zea mays L), capturing the aggregated traits of local varieties, for DayCent ecosystem model simulations, using global crop production data from 2001 to 2013. We selected major cropping regions from the FAO Global Agro-Environmental Stratification as a basis for the regionalization and identified the most important model parameters through a global sensitivity analysis. We calibrated DayCent using the sampling importance resampling algorithm and found significant improvement in DayCent simulations of maize yields with the calibrated regional varieties. Compared to a single type of maize for the world, the regionalization of maize leads to reductions in root mean squared error of 11%, 31%, 27%, 30%, 19%, and 27% and reductions in bias of 59%, 59%, 50%, 81%, 32%, and 56% for Africa, East Asia, Europe, North America, South America, and South and Southeast Asia, respectively. We also found the optimum parameter values of radiation use efficiency are positively correlated with the income level of different regions, which indicates that breeding has enhanced the photosynthetic efficiency of maize in developed countries. There may also be opportunities for expanding crop breeding programs in developing countries to enhance photosynthesis efficiency and reduce the yield gap in these regions. This study highlights the importance of representing regional variation in crop types for achieving accurate predictions of crop yields.

EFFECTS OF ASCORBIC ACID AND SUGAR ON PHYSICAL, TEXTURAL AND SENSORY PROPERTIES OF COMPOSITE BREADS

The present study was carried out to demonstrate the combined effects of different maize flour, ascorbic acid and sugar on the physical, textural and sensory properties of composite breads. The composite flour was prepared using 70% of wheat flour and 30% of flour obtained from grain of differently coloured maize - light blue, blue, red and yellow maize flour. Chemical characterization of composite flours made with four different types of maize was also assessed. Furthermore, the content of total phenolics, flavonoids, anthocyanins, phenolic acids and antioxidant capacity in composite flours was determined. The total of 12 breads that were prepared, four of which were control composite breads, four breads with ascorbic acid, and four were breads with ascorbic acid and sugar. The content of total phenolic compounds showed clear differences among all composite flours. The anthocyanins content determined in composite flours was in the following descending order: blue&gt;red&gt;light blue, while in the yellow maize composite flour anthocyanins were not detected. The results showed that the addition of AsA (0.025%) and sugar (5%) negatively affected the volume as well as the specific volume of composite wheat-maize breads. The texture analysis showed that the addition of AsA in amount of 0.025% had no impact on springiness, cohesiveness and resilience of bread crumb, while it increased crumb hardness. However, composite breads made with AsA and AsA and sugar showed a more compact structure, with a larger number of cells and smaller mean cell areas. Bread samples with AsA and sugar in the tested doses had the lowest springiness, which is indicative of brittleness and reflects the tendency of the bread to crumble when slicing. Results of the sensory evaluation revealed that the AsA and sugar addition had a generally positive effect on the investigated sensory attributes.

Differential response of commercial hybrid and open pollinated maize seeds to mechanical damage during seed processing

Hybrids and open pollinated varieties (OPVs) are two commercial maize seed types cultivated in Nigeria. Information on their response to mechanical damage during processing is limited. This study is thus aimed at assessing the response of hybrids and OPVs of maize seeds to mechanical damage which would facilitate fabrication of processing facilities suitable for either of the maize types. Six maize varieties: three hybids (‘New Kaduna’, ‘SDM-1’, and ‘JO-195’) and three OPVs (‘Sammaz 15’, ‘Sammaz 27’ and ‘Suwan-1-stry’) were used for the study. The seed samples were subjected to standard germination, seedling vigour analysis, accelerated ageing, conductivity and fast green tests. The result showed that all the hybrid seed varieties had more damaged seeds than their OPVs counterpart. Shoot length and root length were more affected than other parts of the seedling. There were differences in the magnitude of electrolyte leakage as well as in what time each seed type (hybrid or OPVs) passed through the phases with ‘JO-195’ having the highest rate of electrolyte leakage. Hybrid seeds had lower resistance to mechanical damage and poorer storability when compared with the OPVs. In the overall, for all the traits, ‘Sammaz 15’, the best among OPVs was more promising when compared with ‘SDM-1’ which was the best among hybrid varieties. Processing machine equipment and accessories that are suitable for hybrid seeds might be inappropriate for conditioning OPVs.

Quality of Chopped Maize Can Be Improved by Processing

The aim of this study was to assess the effect of different maize processing technologies, comparing treatments with conventional rollers (control), MCC MAX rollers and a Shredlage crop processor on the quality of chopped maize. All the three types of chopped maize were harvested on the same day from the same field where the same maize hybrid was grown. The chemical composition of chopped maize, degree of grain processing and particle size fractions, and the effect of the treatments on rumen disappearance of dry matter, organic matter, NDF and starch were assessed. The highest degree of grain processing was achieved with the Shredlage processor (79.2%), and at the same time this processing method had a tendency to produce the highest proportion of physically effective fibre (37.2%). Compared to the conventional rollers (control), the chopped maize produced using the Shredlage processor had higher disappearance of dry matter, organic matter and NDF after 48 h of rumen incubation and of starch after 24 h of incubation. The MCC MAX rollers provided higher disappearance of all nutrients compared to the control treatment after both 24 and 48 h of incubation.

Analyzing the phenolic enriched fractions from Nixtamalization wastewater (Nejayote) fractionated in a three-step membrane process

Nejayote is recognized as the main by-product resulting from the nixtamalization process of maize kernels, which is categorized as an alkaline residue with a chemical composition based on carbohydrates (37.8–55.7%), fiber (22.8–25.5%), protein (4.9–7.4%), and lipids (0.4–1.5%). In addition, Nejayote has an extensive content of simple (e.g., phenolic acids) and complex phenolic compounds (e.g., anthocyanins), which are responsible for the pigmentation and antioxidant activity of maize; therefore, there is a need of their identification depending on the type of maize. The current research has focused on the efficient extraction and identification of the phenolic acids contained in Nejayote after the processing of different types of maize. The target of this work was to fractionate Nejayote from white (NWM), red (NRM), and purple maize (NPM), using three different membranes, such as microfiltration (MF with a pore size of 1 μm) and ultrafiltration (UF100 and UF1 with a molecular weight cut-off of 100 kDa and 1 kDa, respectively), which were strategically applied to extract phenolic acids while retaining other molecules. Such a membrane system exhibited a retention in the first stage of almost all carbohydrates (MF-Retentate: ca. 12–19 g GE/L), while second stage (UF100-Permeate) a concentration of phenolic components was recovered ranging from 768 to 800 mg GAE/L. Finally, in the third stage (UF1-Permeate), 14 phenolic acids were identified, including ferulic and p-coumaric acids, derived from caffeic and ferulic acids, along with other molecules (e.g., glucose and fructose).

English

Genetic characterization of maize genotypes is of great importance in maize breeding program to identify diverse populations and divergent genotypes. Divergence and genetic diversity were assessed in a set of 20 maize genotypes representing popcorn, white corn, sweet corn and yellow corn, through morphological characteristics and Random Amplified Polymorphic DNA (RAPD) markers. Field experiment was conducted in randomized complete block design with three replications. Morphological data revealed that sweet corn genotype SCLY-1 was earlier in days to 50% pollen shedding than other genotypes while white corn genotype WL-3 was earlier in days to 50% silking. Maximum plant height was recorded for PCLY-5 (133.3 cm) while lowest for WL-4 (92.8 cm), whereas highest ears height was recorded for popcorn PCLY-1 (64.4 cm) and lowest (29.4 cm) for SCLY-5. The yellow corn had maximum (4.5 kg) grain yield at harvest as compared to sweet and popcorn (3.0 kg). Negative but weak correlation was recorded between ear height and grain yield. Cluster analysis based on yield related parameters grouped all the studied genotypes in to five sub clusters. Molecular genotyping based on four primers amplified 37 loci which were (100%) polymorphic. Maximum elven loci were identified by primer GLA-04, while minimum was reported for primer GLA-03. The loci GLD-18B1000, GLA-04B300 recorded highest gene diversity (0.500) followed by loci GLE05B750, GLE-05B650 and GLE-05B550. The loci of primer GLD-18 (GLD-18B1000) detected highest alleles evenness and Simpson’s diversity index of 1.00 and 0.526, respectively. Maximum gene diversity (0.354) among populations were recorded for yellow corn, while the minimum was detected for white corn (0.254), while genotypic diversity was same for all maize types. Cluster analysis based on molecular genotypic data grouped the maize genotypes into four distinct groups. Lack of concordance was observed while comparing the clustering based on phenotypic and molecular data. The overall diversity among the studied maize genotypes could be used in future maize breeding program.

Effect of population density on growth and production of hybrid maize

One of the strategies to increase maize production is by selecting the proper combination among variety and planting density. The plant density population experiment was carried out to identify the candidate of maize variety that has high productivity with limited sunlight levels. Our hypothesis was how the erect leaf maize type can get optimal sunlight and affect the productivity. The study was conducted in IP2TP Bajeng, Gowa, South Sulawesi from March to June 2020. This study was designed under split plot design where spacing or plant density as the main plot with 3 levels of treatment (70 cm x 20 cm (population 71,428 plants/ha), 60 cm x 20 cm (population 83,333 plants/ha) and 50 cm x 20 cm (population 100,000 plants/ha). Furthermore, eight genotypes of hybrid maize (ERC 01, ERC 02, ERC 03, ERC 04, ERC 05, ERC 06, ERC 07, ERC 08), including control varieties (JH 45 and Pioneer 36) were treated as the sub-plots. The results indicated that the maize yield increase in line with the increase in plant population. The plant’s spacing of 70 x 20 cm with 100,000 plants/ha was produced 10.61 t/ha, significantly higher than other treatments.