Protein Maize Research Articles

Protein phosphorylation regulates maize endosperm starch synthase IIa activity and protein-protein interactions.

Starch synthesis is an elaborate process employing several isoforms of starch synthases (SSs), starch branching enzymes (SBEs) and debranching enzymes (DBEs). In cereals, some starch biosynthetic enzymes can form heteromeric complexes whose assembly is controlled by protein phosphorylation. Previous studies suggested that SSIIa forms a trimeric complex with SBEIIb, SSI, in which SBEIIb is phosphorylated. This study investigates the post-translational modification of SSIIa, and its interactions with SSI and SBEIIb in maize amyloplast stroma. SSIIa, immunopurified and shown to be free from other soluble starch synthases, was shown to be readily phosphorylated, affecting Vmax but with minor effects on substrate Kd and Km values, resulting in a 12-fold increase in activity compared with the dephosphorylated enzyme. This ATP-dependent stimulation of activity was associated with interaction with SBEIIb, suggesting that the availability of glucan branching limits SSIIa and is enhanced by physical interaction of the two enzymes. Immunoblotting of maize amyloplast extracts following non-denaturing polyacrylamide gel electrophoresis identified multiple bands of SSIIa, the electrophoretic mobilities of which were markedly altered by conditions that affected protein phosphorylation, including protein kinase inhibitors. Separation of heteromeric enzyme complexes by GPC, following alteration of protein phosphorylation states, indicated that such complexes are stable and may partition into larger and smaller complexes. The results suggest a dual role for protein phosphorylation in promoting association and dissociation of SSIIa-containing heteromeric enzyme complexes in the maize amyloplast stroma, providing new insights into the regulation of starch biosynthesis in plants.

Spatial and temporal distribution of Bt proteins in Bt maize leaves

ABSTRACTTo learn the spatial and temporal distribution of Bt proteins in Bt maize leaves, Bt protein levels of Bt maize leaves and their corresponding non-transgenic lines were detected and analysed by the ELISA method. The results showed that Bt proteins were expressed in the leaves of Bt maize varieties during all periods of their growth, while no such Bt proteins were detected in the leaves of non-transgenic maize varieties. The range of leaf Bt proteins was 1.08∼5.81 µg.g−1 FW, which could effectively protect Bt maizes from the corn borer pest during their growth periods. Furthermore, the younger leaves of Bt maizes had significantly lower levels of Bt proteins than their older leaves. In most periods, Bt protein content of Bt maize leaves under drought stress was lower than that under normal growth conditions, but Bt protein content under nutrition stress was higher than that under normal growth conditions. The results provided a full pattern of the spatial and temporal distribution of Bt proteins in Bt maize leaves.

Identification of Salt Stress-Responsive Proteins in Maize (Zea may) Seedlings Using iTRAQ-Based Proteomic Technique.

Background: Soil salinity is a major abiotic stress that limits plant growth and yield worldwide. Objective: To better understand the mechanism of salt stress adaptation in maize (Zea may), proteomic analysis of maize responses to salt stress were analyzed in seedling.Materials and Methods: Taking maize seedlings untreated and treated with NaCl for 24 h as material, isobaric tags for relative and absolute quantitation (iTRAQ) were used to analyze the protein expression profile of maize seedlings after salt stress.Results: The result showed that 270 differentially expression proteins (DEPs) were identified in maize seedlings after salt stress. The majority proteins had functions related to translation, ribosomal structure and biogenesis (15%), posttranslational modification, protein turnover, chaperones (14%) and others metabolism. Quantitative real-time PCR analysis showed that the EF-Tu, peroxiredoxin, FoF1-type ATP synthase, glutamate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, Acetyl-CoA acetyltransferase and nucleoside diphosphate kinase genes were up-regulated in the adaptation of maize to salt stress.Conclusions: The coped with salt stress of maize seedlings might be included nitrogen and glutamate (Glu) metabolism and energy homeostasis, nucleotide transport and metabolism, soluble sugar, fatty acid and nucleoside triphosphates synthesis. Moreover, the enhancement of plant to scavenge ROS, such as peroxiredoxin, might play significant roles in the adaptation of maize to salt stress.Taken together, these proteins might have important roles in defense mechanisms against salt stress in maize.We hope that this study provides valuable information for the further utilization and study on the molecular mechanisms of defense mechanisms in maize.

Assessment of genetically modified maize MON 87427 × MON 87460 × MON 89034 × 1507 × MON 87411 × 59122 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA-GMO-NL-2017-139).

Maize MON 87427 × MON 87460 × MON 89034 × 1507 × MON 87411 × 59122 (six‐event stack maize) was produced by conventional crossing to combine six single events: MON 87427, MON 87460, MON 89034, 1507, MON 87411 and 59122. The GMO Panel previously assessed the six single maize events and 17 of the subcombinations and did not identify safety concerns. No new data on the single maize events or the 17 subcombinations were identified that could lead to modification of the original conclusions on their safety. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins and dsRNA in the six‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the six‐event stack maize, as described in this application, is as safe as its non‐GM comparator and the selected non‐GM reference varieties. In the case of accidental release of viable grains of the six‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the 39 maize subcombinations not previously assessed and concludes that these are expected to be as safe as the single events, the previously assessed subcombinations and the six–event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the six‐event stack maize. Post‐market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the six‐event stack maize and its subcombinations are as safe as the non‐GM comparator and the selected non‐GM reference varieties with respect to potential effects on human and animal health and the environment.

Assessment of genetically modified maize 1507×MIR162 ×MON810×NK603 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA-GMO-NL-2015-127).

Maize 1507 × MIR162 × MON810 × NK603 (four‐event stack maize) was produced by conventional crossing to combine four single events: 1507, MIR162, MON810 and NK603. The GMO Panel previously assessed the four single events and six of the subcombinations and did not identify safety concerns. No new data on the single events or the six subcombinations that could lead to modification of the original conclusions on their safety were identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the four‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the four‐event stack maize, as described in this application, is as safe as its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of viable seeds of the four‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the four maize subcombinations not previously assessed and concludes that these are expected to be as safe as the single events, the previously assessed subcombinations and the four‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the four‐event stack maize. Post‐market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the four‐event stack maize and its subcombinations are as safe as the non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment.

Bioinoculation using indigenous Bacillus spp. improves growth and yield of Zea mays under the influence of nanozeolite.

The online version contains supplementary material available at 10.1007/s13205-020-02561-2.

Effect of nitrogen levels on growth parameters, yield parameters, yield, quality and economics of maize: A review

Nitrogen plays a prominent role in deciding the overall physiological process and biochemical reactions contributing to higher productivity and quality of maize which is a high nutrient exhaustive crop. Optimal dose of nitrogen application is necessary to obtain maximum yield and higher net returns from maize cultivation. The findings of different research scientists and eminent investigators with regard to growth parameters, yield parameters, yield and quality of maize will aid in understanding effect of nitrogen levels on growth parameters, yield parameters, yield, quality and economics of maize. Application of nitrogen at 150 to 200 kg ha-1 is found to be significant in improving the growth, yield (grain yield, Stover yield) and quality (protein content, crude protein and fibre) of maize with maximum net returns for maize cultivators.

Dry matter intake, nutrient digestibility and nitrogen balance of WAD sheep fed ensiled maize stover and concentrate supplement

A study on effect of ensiled maize stover (EMS) and protein concentrate supplement (CS) on nutrient digestibility and nitrogen balance of ensiled maize stover (EMS) and concentrate supplement (CS) by West African Dwarf ewe was carried out. were showed Fifteen West African dwarf ewe with body weight of 14-16 kg allotted to individual metabolic cage in completely randomized design after preliminary feeding trial. The treatments were: A (75% EMS + 25% CS), B (50% EMS + 50% CS), C (25% EMS + 75% CS), D (100%EMS) and E (100% CS). The digestibility study lasted for seven days to determine dry matter digestibility, nutrients digestibility and nitrogen retention of WAD ewe fed ensiled maize stover and concentrate supplement. Results that dry matter intake (DMI), digestible crude protein (DCP), digestible crude fibre (DCF), digestible nitrogen free extract (DNFE), and total digestible nutrients (TDN) ranged from 321.65- 694.41gDM/day, 3.99 - 12.30%, 7.32 - 17.23%, 33.35 – 38.85% and 63.65 – 70.92%, respectively. Dry matter intake of ewe fed sole ensiled maize stover (diet D) was lowest (321.65gDM/day) while animals on diet C (25% EMS+75%CS) had the highest (694.41gDM/d). Apparent digestibility of CP was lowest (3.99%) in ewe fed sole EMS and highest (12.20%) in ewe fed diet C (25% EMS + 75% CS). Positive N-balance was observed for all the five diets, but it was highest (P< 0.05) in diet B (50%+50%) and lowest in diet D (100% EMS). Similarly, N-retention was highest (67.15%) in diet B and lowest (27.61%) in diet D. Therefore, diet made up of 50% ensiled maize stover and 50% concentrate is recommended for sheep production.

Maximizing Maize Grain, Protein, Oil and Starch Yields by Using High Plant Density and Stress Tolerant Genotype

Maximizing Maize Grain, Protein, Oil and Starch Yields by Using High Plant Density and Stress Tolerant Genotype

Predicting functions of maize proteins using graph convolutional network

BackgroundMaize (Zea mays ssp. mays L.) is the most widely grown and yield crop in the world, as well as an important model organism for fundamental research of the function of genes. The functions of Maize proteins are annotated using the Gene Ontology (GO), which has more than 40000 terms and organizes GO terms in a direct acyclic graph (DAG). It is a huge challenge to accurately annotate relevant GO terms to a Maize protein from such a large number of candidate GO terms. Some deep learning models have been proposed to predict the protein function, but the effectiveness of these approaches is unsatisfactory. One major reason is that they inadequately utilize the GO hierarchy.ResultsTo use the knowledge encoded in the GO hierarchy, we propose a deep Graph Convolutional Network (GCN) based model (DeepGOA) to predict GO annotations of proteins. DeepGOA firstly quantifies the correlations (or edges) between GO terms and updates the edge weights of the DAG by leveraging GO annotations and hierarchy, then learns the semantic representation and latent inter-relations of GO terms in the way by applying GCN on the updated DAG. Meanwhile, Convolutional Neural Network (CNN) is used to learn the feature representation of amino acid sequences with respect to the semantic representations. After that, DeepGOA computes the dot product of the two representations, which enable to train the whole network end-to-end coherently. Extensive experiments show that DeepGOA can effectively integrate GO structural information and amino acid information, and then annotates proteins accurately.ConclusionsExperiments on Maize PH207 inbred line and Human protein sequence dataset show that DeepGOA outperforms the state-of-the-art deep learning based methods. The ablation study proves that GCN can employ the knowledge of GO and boost the performance. Codes and datasets are available at http://mlda.swu.edu.cn/codes.php?name=DeepGOA.

Transient expression of gene encoding ZmLEA14A protein in Nicotiana benthamiana plant

LEA protein family includes proteins accumulated in the late stage of embryogenesis and in vegetative tissues of stress-confronted plant. These proteins have been demontrated to play a major role in plant response to abiotic stresses, such as drought and salinity stress. The genes coding for LEA proteins in maize are divided into 9 groups including LEA 1, LEA 2, LEA 3, LEA 4, LEA 5, LEA 6, SMP, dehydrin, and AtM. The application of LEA genes to improve drought tolerance for plants by genetic engineering has also been studied extensively all over the world. In this study, pCAM/35S-ZmLEA14A-35S vector and pCAM/Ubi-ZmLEA14A-35S vector contained the ZmLEA14A gene isolated from Te vang 1, these vectors were used to transient express into Nicotiana benthamiana tobacco leaves by agro-infiltration method. The results of immunoassay between cmyc specific antibodies with proteins from infected leaves revealed the expression of recombinant ZmLEA14A protein in N. benthamiana leaves. Thereby, two constructs habouring the ZmLEA14A gene work at transcription and translation levels in the model plant that could harnessed for stable transformation in plants.

Predicting grain yield and protein content using canopy reflectance in maize grown under different water and nitrogen levels

Predicting grain yield and protein content of maize using spectral reflectance data is very important for improved agricultural production. In this study, we predicted the grain yield and protein content of maize grown under different irrigation and nitrogen levels in 2018 and 2019 based on canopy spectral reflectance measurements at the V6 (sixth leaf), VT (tassel), and R2 (blister) stages. We developed a predictive approach, namely, spectral reflectance–physiological parameters–productivity, to predict grain yield and protein content on maize crop. First, the quantitative relationships between grain yield and protein content and physiological parameters (canopy chlorophyll content [CCC], leaf carbon accumulation [LCA], leaf nitrogen content [LNC], and leaf nitrogen accumulation [LNA]) were analysed. Then, vegetation indices (VIs) and wavelet features based on spectral reflectance were used to establish estimation models for physiological parameters. The physiological parameters were used as a bridge to connect the spectral reflectance data with grain yield and protein content. The purpose was to establish spectral inversion models to indirectly estimate grain yield and protein content. Results showed that grain yield had a significant linear relationship with CCC and LCA. In addition a grain protein content and LNC and LNA were also significantly related under different water, and nitrogen availability. The physiological parameter models with ratio vegetation indices (RVI), biorthogonal 3.3 (bior3.3), and reverse biorthogonal 1.5 (rbio1.5) were reliable in terms of predictability and applicability. Independent data verification suggested that grain yield was predicted using RVI769,758 (R2 = 0.773, RMSE = 2.509) in water availability, rbio1.5781,29 (R2 = 0.744, RMSE = 2.850) in nitrogen availability, and rbio1.5772,11 (R2 = 0.506, RMSE = 2.297) in water–nitrogen availability. In addition, the grain protein content was predicted using RVI793,757 (R2 = 0.704, RMSE = 0.744) in water availability, bior3.3743,19 (R2 = 0.717, RMSE = 0.957) in nitrogen availability, and RVI492,418 (R2 = 0.715, RMSE = 1.224) in water–nitrogen availability. Therefore, maize grain yield and protein content can be accurately predicted using our modelling approach.

In-silico characterization of cadmium stress response-associated Abc1-like protein and its homologues in maize (Zea mays)

Cadmium is a pollutant of concern and accumulates in soil from unchecked industrial activities like smelting, incinerations and combustion. Plants interact via different mechanisms with heavy metal pollutants in soil. Understanding of the plant-soil-metal interactions and the biomolecules involved in this interaction is important to make informed choices for setting breeding goals. In Arabidopsis thaliana, AtOSA1 (A. thaliana oxidative stress-related Abc1-like protein) is involved in response to cadmium stress. The homologous sequences have been deciphered in maize (Zea mays L.). The structures of the maize proteins have been determined. It is observed that multiple proteins sense cadmium and can respond to its presence. Concerted action of all the proteins may be essential to realize full response against cadmium presence in soil and mitigation of plant growth inhibition. Better understanding of the response to cadmium stress would pave way for designing effective breeding strategies for pyramiding beneficial alleles in elite germplasm.

Genetic enhancement of essential amino acids for nutritional enrichment of maize protein quality through marker assisted selection.

Maize grain protein is deficient in two essential amino acids, lysine and tryptophan, defining it as of low nutritive value. The discovery of opaque2 (o2) gene has led to the development of quality protein maize (QPM) that has enhanced levels of essential amino acids over normal maize. However, the adoption of QPM is still very limited. The present study aims at improving the quality of normal four maize inbred lines (LM11, LM12, LM13 and LM14) of single cross hybrids; Buland (LM11 × LM12) and PMH1 (LM13 × LM14) released in India for different agro-climatic zones by introgressing o2 allele along-with modifiers using marker assisted backcross breeding. Both foreground and background selection coupled with phenotypic selection were employed for selection of o2 specific allele and maximum recovery of the recurrent parent genome (87-90%) with minimum linkage drag across the crosses. The converted QPM lines had <25% opaqueness which isclose to the respective recurrent parents. The QPM versions showed high level of tryptophan content ranging from 0.72 to 1.03 across the four crosses. The newly developed best QPM lines were crossed in original combinations to generate QPM hybrids. The grain yield of improved QPM hybrids was at par and there was significant increase in tryptophan content over the original hybrids.The integrated marker assisted, and phenotypic selection approach holds promise to tackle complex genetics of QPM. The dissemination and adoption of improved QPM versions may help to counteract protein-energy malnutrition in developing countries.

Temporal Regulation of the Metabolome and Proteome in Photosynthetic and Photorespiratory Pathways Contributes to Maize Heterosis.

Heterosis or hybrid vigor is widespread in plants and animals. Although the molecular basis for heterosis has been extensively studied, metabolic and proteomic contributions to heterosis remain elusive. Here we report an integrative analysis of time-series metabolome and proteome data in maize (Zea mays) hybrids and their inbred parents. Many maize metabolites and proteins are diurnally regulated, and many of these show nonadditive abundance in the hybrids, including key enzymes and metabolites involved in carbon assimilation. Compared with robust trait heterosis, metabolic heterosis is relatively mild. Interestingly, most amino acids display negative mid-parent heterosis (MPH), i.e., having lower values than the average of the parents, while sugars, alcohols, and nucleoside metabolites show positive MPH. From the network perspective, metabolites in the photosynthetic pathway show positive MPH, whereas metabolites in the photorespiratory pathway show negative MPH, which corresponds to nonadditive protein abundance and enzyme activities of key enzymes in the respective pathways in the hybrids. Moreover, diurnally expressed proteins that are upregulated in the hybrids are enriched in photosynthesis-related gene-ontology terms. Hybrids may more effectively remove toxic metabolites generated during photorespiration, and thus maintain higher photosynthetic efficiency. These metabolic and proteomic resources provide unique insight into heterosis and its utilization for high yielding maize and other crop plants.

The Role of Agrotechnical Factors in Shaping the Protein Yield of Maize (Zea mays L.)

The subject of the work was the evaluation of maize protein yield conditioned by various agrotechnical factors. The test results are derived from two different field experiments covering a total of seven years of observation. Protein yield was significantly dependent on changing weather conditions in the growing seasons. Protein yield was significantly lower in the dry and hot years. The sum of precipitation for the month of May was positively correlated with maize protein yield. However, there was no correlation between the average air temperature and the amount of protein yield. The sum of atmospheric precipitation for the entire growing season (IV–X) shaped maize protein yield in over 96%. A non-linear relationship of the 2nd degree was determined between these traits. Sowing maize into the soil cultivated traditionally (autumn tillage), “stay-green” type cultivars and row fertilization positively influenced maize protein yield. Initial fertilization (regardless of depth) with two-component NP fertilizer, in relation to broadcast fertilization, significantly increased maize protein yield from 11.4% to 18%, respectively. The type of nitrogen fertilizer did not differentiate the value of this trait. Pre-sowing nitrogen application was more effective compared to the top dressing, and significantly increased protein yield. Row fertilization with two-component NP fertilizer clearly affected the content protein in grain. The interdependence of genetic and agronomic progress is an important factor shaping the potential of maize protein yield and cannot be attributed to either breeding (cultivar) or agronomy.

Urban to the bone: Isotopic and faunal dietary data from Formative-period Cerro Jazmín, Mixteca Alta, Oaxaca, México

We investigate the dietary impact of urbanism on the population of Cerro Jazmín, a Late and Terminal Formative urban center in the Mixteca Alta region of Mexico (300 B.C.-A.D. 300). We reconstruct the urban diet from faunal analysis and isotopic results from 24 individuals recovered from formal burials. Bone collagen and bone and enamel apatite isotopic data provide C, N, and O values describing diet and breastfeeding patterns. Carbon values suggest a narrow diet heavily based on maize and little animal protein. Individuals 0–3 years of age had significantly higher nitrogen and oxygen values than adults, suggesting that these infants may have still been breastfeeding at the time of death. Weaning likely occurred between 3 and 5 years of age when C3 foods, perhaps squash, supplemented maize atole in the weaning diet. Isotopic and faunal evidence suggest that the Cerro Jazmín population did not supplement their diet by hunting or trapping wild animals. Instead, animal protein came from domesticated animals, mainly dogs that were fed a C4 rich diet. The data suggest that urban dwellers had little dietary autonomy and may have fully relied on the urban food production and distribution system for the bulk of their diet.

A SnRK1-ZmRFWD3-Opaque2 Signaling Axis Regulates Diurnal Nitrogen Accumulation in Maize Seeds.

Zeins are the predominant storage proteins in maize (Zea mays) seeds, while Opaque2 (O2) is a master transcription factor for zein-encoding genes. How the activity of O2 is regulated and responds to external signals is yet largely unknown. Here, we show that the E3 ubiquitin ligase ZmRFWD3 interacts with O2 and positively regulates its activity by enhancing its nuclear localization. Ubiquitination of O2 enhances its interaction with maize importin1, the α-subunit of Importin-1 in maize, thus enhancing its nuclear localization ability. We further show that ZmRFWD3 can be phosphorylated by a Suc-responsive protein kinase, ZmSnRK1, which leads to its degradation. We demonstrated that the activity of O2 responds to Suc levels through the ZmSnRK1-ZmRFWD3-O2 signaling axis. Intriguingly, we found that Suc levels, as well as ZmRFWD3 levels and the cytonuclear distribution of O2, exhibit diurnal patterns in developing endosperm, leading to the diurnal transcription of O2-regulated zein genes. Loss of function in ZmRFWD3 disrupts the diurnal patterns of O2 cytonuclear distribution and zein biosynthesis, and consequently changes the C/N ratio in mature seeds. We therefore identify a SnRK1-ZmRFWD3-O2 signaling axis that transduces source-to-sink signals and coordinates C and N assimilation in developing maize seeds.

Determining the 4th limiting amino acid in low crude protein diets for male and female Cobb MV × 500 broilers

ABSTRACT 1. Four experiments were conducted to determine the 4th limiting amino acid (AA) in maize–soybean meal-based diets. 2. Deletion assay methodology was used to quantify performance and carcase trait responses to potential deficiencies in essential and conditionally essential AA caused by reductions in dietary crude protein of maize–soybean meal-based diets from 202.9 to 186.5 g/kg. 3. The deletion of Val, Phe and Gly + Pro resulted in negative effects on live performance and carcase traits for male broilers, whereas AA deletion only affected wing weights for females with no response on live performance. 4. Further experimentation could not duplicate a response to Phe or Pro in male broilers. 5. Valine was identified as the potential 4th limiting AA in maize–soybean meal-based diets and was not found to be co-limiting with Ile.

Exogenous α-amylase supplementation reduces the variability of ileal digestible energy in broiler chickens fed complete diets with maize batches of variable protein solubility

This study evaluated the relationship between salt-soluble protein (SSP) of maize and the apparent ileal digestibility (AID) of complete diets in response to exogenous α-amylase supplementation in broiler chickens. Samples of 12 maize batches originating from the mid-north and northeast of China were analyzed for SSP. Six of the 12 sources of maize with a wide variation of SSP (from 21.1 % to >50 %) were selected. Six maize-soybean meal basal diets were formulated, including each source of maize with or without the addition of α-amylase (Ronozyme® HiStarch; DSM Nutritional Products). A total of 960 day-old male Arbor Acres Plus broiler chickens were randomly allocated to 12 treatments with 8 replicates per treatment in wired cages and fed experimental diets in 2 phases (d 1−14; d 15−28). At d 28, 4 birds selected from each cage were euthanized for evaluation of apparent ileal digestibility (AID) of starch and energy. The addition of α-amylase reduced the feed conversion ratio (FCR) of chickens from 1 to 28 d (1.407 vs. 1.426) compared to the basal diets across maize batches, particularly from 1 to 7 d (1.049 vs. 1.078). An interaction between maize batch and α-amylase supplementation on FCR was detected only at 7 d, when the batch with the lowest SSP exhibited the greatest response to α-amylase. Neither a main effect of α-amylase nor an interaction with maize batch on AID of starch were detected (P > 0.05). Nonetheless, α-amylase supplementation increased ileal digestible energy (IDE) from 12.21 to 12.50 MJ/kg dry matter across maize batches. These increments were mainly driven by the maize batch with the lowest SSP. α-amylase supplementation reduced the variability of IDE from a coefficient variance (CV)=5.2 % to a CV=0.7 % across maize batches. Interestingly, there was a strong negative correlation (r<-0.95; P < 0.001) between the initial IDE of maize and the IDE response to α-amylase, and a less strong correlation between SSP and the IDE response to α-amylase (r=-0.78, P = 0.07). SSP was not a predictor of starch digestibility at this age. Dietary α-amylase supplementation has the potential to significantly reduce the variability in the energy value of maize-based diets in commercial poultry production by improving the nutritional value of poorly digestible maize.