Yellow Maize Hybrids Research Articles

Resistance response of yellow maize inbreds and F1 crosses against Philippine downy mildew [Peronosclerospora philippinensis (Weston) C.G. Shaw]

Maize is one of the world's most important staple crops, yet various pests and diseases impede its optimal production. Philippine maize downy mildew disease (PDM) caused by Peronosclerospora philippinensis (Weston) Shaw is one of the most devastating diseases in corn-growing areas in Asia. Breeding for resistant varieties is the most cost-effective and environmentally safe alternative for controlling the disease. In this study, we evaluated the resistance responses of yellow maize inbreds and hybrids against PDM to select promising genotypes for genetic analysis and varietal improvement. Resistance trials under greenhouse conditions were conducted to investigate the PDM resistance response of 14 selected CIMMYT lines (CMLs) and IPB Var 6 (susceptible check) to select potential parents prior to hybridization. CML 431 and CML 452 were identified to have significantly low disease incidence among the test genotypes. Subsequently, disease evaluation of the two inbred lines with putative DM resistance, four experimental hybrids derived from these inbred lines, and checks was performed in the field. Across three validation trials, inbred CML 431, and hybrid CML 452 × CML 431 showed degrees of resistance to PDM. This study's findings enabled the identification of resistant lines to downy mildew for the generation of mapping populations for genetic association studies, as well as the establishment of experimental units for transcriptomics research.

Variabilidade do regime hídrico durante a fenofase de florescimento de híbridos de milho de grãos brancos e amarelos e sua relação com a produtividade de grãos

ABSTRACT The impact of low water availability on maize yield depends on the severity of the water deficit and the phenological stage of the crop. The objective of this study was to evaluate the variability of the water regime during flowering in white (GB) and yellow (GA) maize hybrids and its effects on grain yield. The study was conducted under field conditions in a pelic vertisol soil in Celaya, Guanajuato, Mexico. The drought condition of the crop was 75% of soil humidity with a soil water potential of -1.5 MPa. Hydraulic conductivity (Lp), water (Ψr) and osmotic (Ψs) potentials of the roots (during flowering phenophase), grain yield and water productivity were the evaluated variables. As results, significant variability of the water regime variables was obtained among the evaluated hybrids, resulting in variation of grain yield. The white-grain hybrids with the highest Lp were GB4 and GB5 and for yellow-grain GA2 and GA10, all exceeding 347.75 mg m-1 s-1 MPa-1. In some hybrids Ψr and Ψs, decreased to more than -1.85 and -2.80 MPa, respectively, showing positive responsiveness during flowering to the drought condition of the soil. There was positive and significant correlation between Lp x Yield, and highly significant negative correlation between Ψs x Yield. The highest yielding hybrids were GB4 (8000 kg ha-1) and GA2 (7800 kg ha-1). These hybrids will continue to be evaluated for other variables for validation and recommendation for drought conditions.

ESTIMATION OF MAIZE GENETIC COEFFICIENTS FOR THE CERES-MAIZE MODEL USING NON-DESTRUCTIVE METHODS

The Crop Environment Resource Synthesis-Maize (CERES-Maize) mechanistic model, included in the Decision Support System for Agrotechnology Transfer (DSSAT), is a useful and powerful tool that simulates the growth and yield of maize in different environments. The qualitative and quantitative information provided to the CERES-Maize model guarantees reliability in the simulations obtained. However, it requires a lot of information such as soil characteristics, daily climate, crop characteristics and management, as well as six genetic coefficients. This research assessed a non-destructive methodology for estimating the six required parameters (genetic coefficients): P1, P2, P5, G2, G3 and PHINT, based on the maize physiology, measured from the Growing Degree Days (GDD) base 10. An experiment was established at the experimental station of the International Maize and Wheat Improvement Center (CIMMYT) in Tlaltizapan, Morelos, Mexico, where 27 white maize hybrids and 14 yellow maize hybrids were manually sown in an irrigation conservation tillage system. Once the simulations of maize growth and yield were obtained with CERES-Maize model, the genetic coefficients were calibrated using the Generalized Likelihood Uncertainty Estimation (GLUE). After calibration of the six genetic coefficients for all hybrids, an average values of P1, G2 and G3 were within the typical range, while P2 and P5 were greater than the typical range, and PHINT was below typical range. However, the simulation model showed good performance after calibration, according to the average R2 of 0.9809 and 0.9730 between measured and simulated yields for white and yellow hybrids respectively. The coefficients estimated in this study can be used in the CERES-Maize model to simulate maize yields in different regions of the country for the hybrids used here.

Novel Combination of the Biophysical, Nutritional, and Nutraceutical Properties in Subtropical Pigmented Maize Hybrids.

Maize (Zea mays L.) represents the main caloric source for much of the world's population. Pigmented maize varieties are an excellent source of nutraceutical compounds: blue and yellow maize are rich in anthocyanins as well as carotenoids and phenolic acids, respectively. However, blue maize is usually grown in small quantities as a specialty crop because it lacks the qualities and adaptations of commercial white and yellow varieties. Here, a new high-yield variety of blue maize called Vitamaiz was developed from inbred lines of subtropical blue, white, and yellow maize. The aim of this study was to characterize the nutraceutical and physical properties of 30 Vitamaiz hybrids in two subtropical locations. Kernel physical traits, nutrient composition, and nutraceutical components (free phenolic acids, FPA; cell wall-bound phenolic acids, BPA; total monomeric anthocyanin content, TAC; antioxidant capacity, AOX by oxygen radical absorbance capacity assay, and total carotenoid content, TCC) were evaluated. The biophysical traits of the hybrids were suitable for nixtamalized and flour maize industries. High levels of FPA (228 mg GAE/100 g), BPA (635 mg GAE/100 g), and AOX (2.0 and 8.1 mM Trolox equivalent/100 g for FPA and BPA, respectively) were also detected with elevated TAC levels (274 mg C3G/kg dw) and AOX activity (3.1 mM Trolox equivalent/100 g). This is the first study to characterize Blue × Yellow maize hybrids that adapt to subtropical environments.

Hydration kinetics of commercial white maize (Zea mays L.) hybrids, and associations with grain intrinsic and wet-milling properties

The hydration kinetics of 26 commercial white maize hybrids/varieties were investigated, satisfactorily (r > 0.9; P < 0.01) described by the Peleg model and related to the physical, chemical and wet-milling properties of the maize hybrids. The Peleg constants K1 [0.142–0.294 h(g/100 g solids)−1], K2 [0.030–0.037 (g/100 g solids)−1] and equilibrium moisture content, ME, [41.76–47.83 g/100 g solids] showed genotypic differences. The distributions, associations and groupings of the maize hydration, physical, chemical and wet-milling properties were evaluated with Principal Component Analysis (PCA), Pearson's correlation coefficients and clustering analysis using Agglomerative Hierarchical Clustering (AHC). The Peleg K2 was influenced by the grain protein content and kernel density, and concomitantly impacted the starch yield. The ME also related to the starch yield, in addition to the starch recovery. The AHC analysis was extended to include 16 commercial yellow maize hybrids from our previous study. The groupings of the resulting 42 of the most widely grown maize hybrids/varieties in México confirmed the close association between maize water absorption, physical, chemical and wet-milling properties. The findings on the hydration kinetics, and the starch yield and recovery from wet-milling are of specific interests to the maize industry.

Response of Two Yellow Maize Hybrids to Amino Acids, Mineral Npk and Nano-Fertilizers under Toshka District Conditions

This study was carried out during 2018 and 2019 seasons at the Experimental Farm of the Water Studies and Research Complex (WSRC) Station, National Water Research Center, Toshka Region, Egypt (22°32′16″N, 31°30′40″E), to study the effect of two amino cat fertilizer concentrations (AA1: 100 cm3 fed-1 and AA2: 200 cm3 fed-1), six different combinations of mineral NPK and nano-fertilizers (F1= 0.0 fertilizers-control treatment, F2= 100% mineral NPK (120:30:24 kg fed-1), F3= 100% Nano NPK )10 kg fed-1), F4=75% mineral NPK +25% Nano NPK, F5=75% Nano NPK +25% mineral and F6= 50% mineral NPK +50% Nano NPK( on grain production and its attributes as well as net economic return on two yellow maize hybrids (M1: T.W.C. 353 and M2: T.W.C. 360). The experiment was laid out in a strip split-plot design with three replications, where amino cat fertilizer allocated in vertical-plots, fertilization treatments were arranged in horizontal-plots and maize hybrids were occupied the sub-plots. Studied traits were number of days to 50% tasseling, number of green leaves plant-1, ear leaf area, plant height, ear length, number of ears plant-1 and grain yield fed-1. Obtained results showed that maize hybrids, amino cat fertilizer, fertilization treatments, and their interactions significantly influenced most studied traits in both seasons. TWC 353 hybrid gave the maximum mean values of all studied traits in both seasons. Foliar spraying with 200 cm3 amino cat fertilizer was significantly associated with corresponding increases in all studied traits especially grain yield (3.02 and 3.06 ton fed-1) in the 1st and 2nd seasons, respectively.Maximum average values of studied traits were obtained using 50% mineral fertilization + 50% nano- NPK fertilization in both growing seasons. Foliar appliction of TWC 353 hybrid with 200 cm3 amino-fertilizer, beside fertilization by 50% mineral NPK+50% NPK nano-fertilizers (M1AA2F6), recorded the highest values for net farm incom (12926 L.E fed-1), net farm return (6360 L.E fed-1), BCR (1.97) and economic efficiency (net return/total costs=0.97). This result is due to the highest grain yield prodictivity under this treatment (3.77 ton fed-1) as an average of the two seasons compared with other treatments. Generally, it could be concluded that foliar spraying of maize hybrid TWC 353 with 200 cm3 fed-1 amino cat fertilizer plus 50% mineral fertilization + 50% nano-NPK fertilization resulted in highest growth, production and net farm return under the environmental conditions of Toshka region.

GENETIC DIVERSITY OF EXTRA-EARLY YELLOW MAIZE HYBRIDS UNDER STRIGA ENVIRONMENTS

The success of any breeding program depends on the ability to determine germplasm diversity and genetic relationships among breeding materials. Genetic diversity is an invaluable aid in crop improvement. This study was carried out to determine the genetic diversity among 70 extra-early yellow maize hybrids under Striga environments. Cluster and principal component (PC) analyses were used to determine the genetic diversity of the hybrids. Data on morphological and agronomical data were collected. The experiment was set up in two locations (Abuja and Mokwa) in a randomized incomplete block design experiment with two replications. A significant difference was observed among the hybrids in all the traits studied and a significant genotype × environment interaction was observed for all traits except for plant height, anthesis silking interval and Striga count at 8 and 10 WAP. The principal component reveals that the first three components account for 86% variability. PC1 gave maximum variability (43%) and was loaded with PC1 and the first four PCs can be utilized in hybridization programs. The principal component biplot reveals the relationship among traits and the distance of each variable in determining variability among hybrids. The cluster diagram reveals five distinct groups. Group IV consisted of Striga tolerant hybrids and group I consisted of susceptible hybrids. Both principal component and cluster analysis revealed the genetic diversity among the hybrids and identified genotypes that were Striga tolerant and could be selected as choice of parental materials to develop Striga resistant materials

Field Performance of Three-way Cross Yellow and White Maize Hybrids in Nepal

Maize hybrids can increase production, bridge the yield gap, and boost up domestic production in Nepal. Three-way cross hybrid introduces an alternative to produce low cost hybrid seed for resource poor farmers. A study was performed to identify promising yellow and white maize hybrids developed by International Centre for Maize and Wheat Improvement (CIMMYT), Mexico in Rampur, Nepal. Nineteen three-way cross white maize hybrids with two checks and seventeen yellow maize hybrids with one check were tested in field experiments on 2017 and 2018. Treatments were replicated twice in α-lattice design with each experimental plot of 9.6-m2 (4-m × 2.4-m). AF17A-426-13/14, AF17A-426-1/2, AF17A-426-28/39, and AF17A-426-15/16 were the three-way cross white hybrids produced grain yield of more than 9000 kg ha-1. Similarly, AF17A-473-20/29 and AF17A-473-18/27 yielded about 9000 kg ha-1 among the three-way cross yellow maize hybrids. These hybrids have commercial potentials to increase maize yield in Nepal if the provided parents are successful in the seed production.

Yield gains larger in GM maize for human consumption than livestock feed in South Africa.

The majority of genetically modified (GM) crops are produced for livestock consumption, whereas minimal attention has been given to GM crops for direct human consumption. In South Africa, GM white maize has been grown for direct human consumption alongside GM yellow maize and conventional hybrid (CH) maize for livestock feed since 1999. Here we investigate yield differences between GM white, GM yellow and CH maize across 106 locations, 28 years, 491 cultivars, and 49,335 dryland and 9,617 irrigated observations in South Africa. GM maize increased mean yields over CH by 0.42 metric tons (Mt) ha-1 and reduced yield risk. We show that GM white maize increased yields by 0.60 Mt ha-1 and GM yellow maize by 0.27 Mt ha-1 compared with CH maize. GM yield gains were similar for dry and irrigated production. Our study highlights the potential impacts of growing GM grain crops for human consumption in African countries.

Mogućnosti primene suve destilerijske džibre u smešama za ishranu životinja

The possibility of utilization of dried distillers' grains with solubles (DDGS) in animal feed was investigated. Samples of maize hybrids ZP 548 and ZP 655b, and DDGS obtained from hybrids ZP 548 and ZP 548c were used as components of the feed. The total protein content ranged from 12.42% to 31.18%, moisture from 5.49% to 9.55, and ash content from 1.85% to 4.37%. The contents of NDF, ADF, ADL, hemicellulose and cellulose fibers ranged from: 13.90% to 48.13%; 2.9% to 20.69%; 0.27% to 2.44%; 10.69% to 30.17%, 2.62% to 18.32%, respectively. In vitro, dry matter digestibility ranged from 55.20% to 89.76%. It was concluded that the samples of DDG obtained from red and yellow maize hybrids kernel are very suitable as components for the preparation of animal feed.

Intercropping Cowpea with Some Yellow Maize Hybrids Under Different Nitrogen Fertilizer Rates

Intercropping Cowpea with Some Yellow Maize Hybrids Under Different Nitrogen Fertilizer Rates

Effect of Mineral and Nano Nitrogen Fertilizers on Yield and Yield Components of Some Yellow Maize Hybrids

Two field experiments were conducted at the Experiment and Research Center, Fac. Agric., Moshtohor, Benha Univ., during 2018 and 2019 summer seasons. The aim of this was to study response of three yellow maize hybrids (SC 2055, SC 176 and SC P3737) to three N fertilizer rates (60, 90 and 120 kg N fed-1) and two Nano-N foliar applications (Without and Nano foliar applications). The experimental design was randomized complete block design (RCBD) using split split-plots arrangement with three replications. The yellow maize hybrids, N fertilizer levels and Nano-N foliar applications were arranged at random in the main plots, sub- plots and sub sub-plots, respectively. Single Cross P3737 was significantly earlier than the other hybrids regarding 50% tasseling and silking. Also, SC P3737 was superior to the other two hybrids in most of the studied traits. The highest values of plant height, ear length, ear diameter, No. grains row-1, ear weight, ear grains weight, 100-grain weight, Forge yield fed-1 and grain yield fed-1 were obtained with fertilizer level of 120 N fed-1. On the other hand, the earliest tasseling and silking were recorded with 60 kg N fed-1. Nano foliar application gave the greatest of all grain yield and attributes of yellow maize hybrids as compared with untreated. It could be concluded that under the conditions of the experiment, planting SC P3737 under 90 or 120 N fed-1 and nano foliar application is recommended.

Potentials of organic manure and potassium forms on maize (Zea mays L.) growth and production

Worldwide, maize (Zea mays L.) is considered an important food and fodder crop. Compost as a soil amendment and potassium (K) could enhance the maize yield. Therefore, two field experiments were carried out in the two seasons 2017 and 2018 to study the effects of compost at three levels and four forms of potassium fertilization on the yellow maize hybrid ‘Pioneer SC 30N11’ yield components. To conduct the field trials, a split plot system in three replications was established. Three compost levels (0, 5 and 10 ton/ha) were in the main plots, and four potassium forms (untreated, nano-potassium fertilizer, humic acid and potassium sulfate) were in the subplots. Plot size was 10.50 m2, with 5 ridges with 3 m length and 0.7 m width. The results indicated that the application of compost (as organic manure) and the potassium forms significantly affected the plant height, ear length, grains number/rows, grains number/ear, 100- grain weight, straw and biological yields, grain protein and K contents in both seasons. Increasing the compost from 5 to 10 ton/ha increased the yield, its components, protein and K contents. The foliar application of nano-potassium followed by humic acid increased all the studied characteristics. The interaction between compost manure (10 ton/ha) and nano-potassium (500 cm3/ha) or humic acid (10 ton/ha) recorded the highest mean values for all parameters during both harvest seasons.

Kinetics of water absorption and relation with physical, chemical, and wet‐milling properties of commercial yellow maize ( Zea mays L.) hybrids

The kinetics of water absorption of 16 commercial yellow maize hybrids were investigated, and their relationships with the physical, chemical, and wet-milling properties of the grains were examined. The Peleg equation adequately (r > 0.9, p < .001) described the water absorption characteristics. The Peleg constants K1 [0.185–0.278 hr (g/100 g solids)−1] and K2 [0.030–0.038 (g/100 g solids)−1] significantly (p ≤ .05) depended on the hybrids, so also was the equilibrium moisture content, ME, (40.30–49.17 g/100 g solids). Pearson's correlation analysis showed the Peleg constants were highly dependent on the physical and chemical properties of the grains. The Peleg constant K2 significantly (p ≤ .05) related to the starch yield (K2, r = −0.641), which is a very important wet-milling property. Hence, to screen the maize hybrids for their wet-milling properties, their water absorption kinetic parameters or the resulting Peleg constants can be used. Practical applications During wet-milling of maize, steeping or soaking is the first and most important stage that induces several physical and chemical changes that aid separations of kernel components and affect the product quality. Investigating the kinetics of water absorption in several yellow maize hybrids, our results revealed that the hydration parameters depend on the hybrids and correlated with their physicochemical and wet-milling properties. Starch yield and recovery can be predicted from grain hydration parameters, offering a screening option for the wet-milling industry. The information is also useful for breeders, farmers, and marketers in selecting maize hybrids for wet-milling.

EFFECT OF PLANT DENSITY AND N-FYM COMBINATION FERTILIZER LEVELS ON TWO YELLOW MAIZE CULTIVARS PRODUCITIVY

Two field experiments were conducted during two consecutive summer seasons of 2014 and 2015 in an administrative field at Diarb Negm District, Sharkia Governorate, under Agronomy Department supervision, Faculty of Agriculture, Zagazig University, Egypt. The aim of this study was to investigate the response of two yellow maize hybrids (Single Cross 176 and Three-way Cross 352) to three plant densities (20000, 24000 and 30000 plants/fad.), and nitrogen-farmyard combination fertilizer levels (60, 80 and100 kg N/fad., without addition of farmyard manure (FYM) and 60 kg N/fad.+20 m3 FYM/fad., 80 kg N/fad.+ 20 m3 FYM/fad., and 100 kg N/fad.+20 m3 FYM/ fad.) under clay soils conditions. The obtained results could be summarized as follows: The tried three maize plant densities had different effects on plant height (cm), ear diameter and length (cm), number of rows/ear, number of kernels/row, 100-kernel weight, kernel weight/ear, and biological yield (ton/fad.) during both seasons and their combined analysis, but the differences among the tried three maize plant densities on aforementioned traits did not reach the level of significance. Results of the first season and the combined analysis detected significant differences among the tried plant densities on ear yield/fad. Where, ear yield/fad., and grain yield/fad., in the first season and combined analysis, harvest index and grain: stover ratio in the two seasons and their combined analysis were significantly increased due to increasing maize density from 20000 or 24000 and up to 30000 plants/fad. Maize SC 173 cultivar appeared to produced taller plants, longer ears and larger number of kernels/row than TWC 352 cultivar. The later produced larger ear diameter, number of rows/ear, 100-kernel weight, kernel weight/ear, ear yield/fad., grain and biological yields/fad., than SC 173 one. No significant differences between two maize cultivars regarding harvest index and grain: stover ratio was observed. The first and the second increments in nitrogen levels up to 100 kg N/fad., with or without addition of farmyard manure was accompanied by a significant increase in ear diameter (cm), ear length (cm), number of rows/ear, number of kernels/row, 100-kernel weight (g), kernel weight/ear (g), ear yield/fad., grain and biological yields (ton/fad.) but harvest index and grain: stover ratio were reduced during both seasons and their combined analysis. These results finally recommend sowing maize cultivar TWC 352 with dense planting of 30000 plants/fad., and raising nitrogen level up to 80 kg N/fad., with addition of farmyard manure to maximize grain yield/fad., under the experimental site and other likely environmental condition.

Testcross performance and combining ability of early maturing maize inbreds under multiple-stress environments

Availability of multiple-stress tolerant maize is critical for improvement in maize production in West and Central Africa (WCA). A study was carried out to (i) assess a set of inbred lines for combining ability under stressed and optimal conditions, (ii) determine the performance of the testcrosses under different conditions, and (iii) identify outstanding hybrids across the conditions. Two hundred and five testcrosses were planted with five hybrid checks under Striga-infested, low soil nitrogen, drought and optimal conditions between 2015 and 2016 in Nigeria. The grain yield inheritance under optimal condition was largely regulated by additive gene effect whereas non-additive gene effects largely regulated grain yield under the three stresses. Four of the inbreds had significant positive general combining ability effects each under low N and drought, and three under Striga infestation for grain yield. The inbreds could be vital sources of beneficial alleles for development and improvement of tropical yellow maize hybrids and populations. Hybrids TZEI 443 x ENT 13 and TZEI 462 x TZEI 10 were high yielding and stable; they out-performed the three early maturing released hybrids in WCA. The new hybrids should be extensively assessed and released in the sub-region to improve food security.

Evaluation of wet-milling performance of commercial yellow maize hybrids grown in México and relations with grain physicochemical properties

The use of commercial maize hybrids is a common practice worldwide because of improved yield potential and agronomic characteristics. However, there is very little information regarding their quality characteristics and industrial potential. In this study, 16 commercial yellow maize hybrids, cultivated in the same location, were evaluated for compositional, physical and wet-milling properties. Grain contents of protein (8.5–12.3%, db), crude fat (3.9–5.7%, db) and starch (69.0–72.8%, db) showed varietal differences that were also reflected in, amongst others, thousand-kernel weight (350–430 g), pericarp (4.5–7.7%, db), thickness (3.9–4.9 mm), flour Hunter b color value (28.0–44.6), and 48-h moisture saturation point (0.33–0.46 (g water absorbed/g sample)). The starch yield from the wet-milling varied from 45.0 to 69.5% (db), with a concomitant recovery (%, db) of 64.2–96.2. These properties were correlated and modeled to predict the starch yield that was highly significantly dependent (r2 > 0.7; P < 0.001) on the protein content and kernel density, with the latter accounting for most of the variations. The results suggest that kernel density would be a good indicator of starch yield, and its evaluation could be useful in screening suitable maize hybrids for wet-milling.

Stability of Maize Hybrids across Environments Using Gge Biplot and Ammi Analysis

Twenty six yellow maize hybrids on the basis of stability analysis were evaluated in National Uniform Maize Hybrid Yield Trials conducted across eight diversified environments of Pakistan. Combined analysis of variance based AMMI analysis shown highly significant differences for environments, genotypes and their interactions. The environments explained about 78 percent of the total yield variation followed by genotype by environment interaction. Environment was the main aspect that influences the performance of maize yield in study area. The first two interaction principal component axes (IPCA1 and IPCA2) explained about 63 percent of the grain yield variation due to genotype and genotype by environment interaction (GGE). The GGE biplot analysis shown that entry-2 (Mex-YLHY2) was the most stable hybrid and can be considered as adaptable to all the environments.

Evaluation of Some Yellow Maize Hybrids for Grain and Forage Yields Productivity

Evaluation of Some Yellow Maize Hybrids for Grain and Forage Yields Productivity

Estimates of combining ability for grain yield and other agronmic traits in yellow maize hybrids

Estimates of combining ability for grain yield and other agronmic traits in yellow maize hybrids