Maize Zea Mays Research Articles

Dietary habits of lesser bandicoot rat (Bandicota Bengalensis) in an agro-ecosystem, Pothwar Plateau, Pakistan.

Dietary habits of bandicoot rats (bandicota bengalensis) were investigated in the agricultural crops of the Pothwar Plateau, Pakistan by analysing stomach contents. The research activities were conducted in major field crops including wheat-groundnut and in the fallow lands during non-crop season at the field boundaries. The specimens were captured from the fields using kill/snap traps, and dissected to collect their stomach samples for laboratory analysis. Light microscopic slides of the plant material were recovered from stomach samples and the reference materials were collected from the field. Results revealed that the bandicoot rat predominantly fed upon cultivated crops during cropping season but consumed wild vegetation during non-cropping season. There was no significance difference between summer and winter diets. Most frequently consumed crop food items were wheat (Triticum aestivum; 28.57%), groundnut (Arachis hypogea; 11.26%), sorghum (Sorghum bicolor; 10.17%), chickpea (Cicer arietinum; 9.52%), maize (Zea mays; 6.49%), millet (Pennisetum glaucum; 5.84%), barley (Hordeum vulgare; 4.98%) and mustard (Brassica campestris; 4.98%). Among wild vegetation were consumed khbal gha (Cynodon dactylon; 7.79%), baron dhab (Demostachya bipinnata; 7.36%) and Prickly flower (Achyranthes aspera; 3.03%). The study concludes that, in addition to consuming wheat and groundnut crops, the Lesser bandicoot rat also subsists on grasses, weeds, and some fodder crops, as important component of its diet in agro-ecosystem of the Pothwar Plateau.

EVALUATION OF NITROGEN FERTILIZER AND ROW SPACING EFFECT ON YIELD AND PHYSIOLOGICAL CHARACTERISTICS OF MAIZE (Zea mays L.) UNDER IRRIGATED AND RAINFED CONDITIONS

This research aims to investigate the yield and physiological traits of Hybrid 704 Single Cross maize under rainfed (without any irrigation) and irrigation based on plant needs as a split-plot experiment in a randomized complete block design with three replications during 2017-2018. It was carried out in Langrud, Gilan province, Iran. The total amount of precipitation during the plant growth period was 580.4 and 463.4 mm in 2017 and 2018 respectively, which happened to improper distribution during the plant growth. In experimental treatments, the first factor includes irrigation and rainfed in the main plots and the second factor is the combination of urea fertilizer levels (control, applying 100, 200, and 300 kg per hectare) with row spacing (10, 20, and 30 cm distance) were in sub-plots. The results showed that the effect of nitrogen source and row spacing under rainfed and irrigation conditions was significant on all investigated traits in this experiment. In the conditions of rainfed, the maximum grain yield was 11394.6 kg.h-1 for applying 300 kg of nitrogen fertilizer per hectare and 20 cm row spacing. In irrigation conditions, the highest grain yield was assigned to 200 and 300 kg of nitrogen fertilizer per hectare and of 20 cm row spacing, with an average of 14050.5 and 14993 kg per hectare, respectively. In addition, an increase in physiological traits, including relative water content, proline, antioxidant activity, and improvement of electrolyte leakage under rainfed conditions was observed by applying nitrogen fertilizer and increasing the row spacing. As a result, in rainfed conditions, using 200 to 300 kg of nitrogen fertilizer and increasing the row spacing should be used to obtain the highest maize yield in the experimental area.

Soil Chemical Properties and Microbial Behavior under Short-Term Organic and Mineral Fertilization within Different Crops

Agronomic practices can have a negative impact on soil health and quality and ecosystem resilience. The objectives of the study were (1) to evaluate the soil chemical properties and microbial abundance under short-term application of organic and mineral fertilizers and different cultivated crops and (2) to observe the antifungal efficacy of microorganisms isolated from the studied soil. A field trial was conducted in the 2021–2022 period on a preluvosoil-type soil in four randomized blocks with eight fertilizer treatments based on manure compost (MC) and MC + mineral fertilizer (V1—control-soil; V2—NPK only; V3—15 t/ha MC; V4—15 t/ha MC + NPK; V5—30 t/ha MC; V6—30 t/ha MC + NPK; V7—60 t/ha MC; and V8—60 t/ha MC +NPK) and four crops (winter wheat—Triticum aestivum L., maize—Zea mays L., soybean—Glycine max L., and a mixture of perennial grasses and legumes). In almost all treatments, the soil pH decreased during the summer–autumn period. The organic carbon (Corg) and humus contents increased compared to the initial state of the soil after the application of different doses of MC and MC + NPK fertilization in almost all treatments. The microbial load of the soil was influenced by the fertilization regime and crop species, but there were no significant differences between the variants. The highest bacterial load was recorded in soil cultivated with a mixture of perennial grasses and grain legumes, i.e., in the variant with 15 t/ha MC, followed by soil cultivated with maize and fertilized with 30 t/ha and 60 t/ha MC. A higher number of fungi was observed in the mixture of perennial grasses and legumes, and Rhizobium population was higher, especially in the winter wheat plots, despite the fertilization regime. The antifungal efficacy of the microorganisms isolated from the samples was medium to low, except in the winter wheat experiment, where the efficacy against Fusarium culmorum was medium to high and against other pathogens was medium. In the other crops within the experiment, the antagonistic activity of the soil microorganisms was medium to low.

Evaluation of economic loss caused by Indian crested porcupine (Hystrix indica) in agricultural land of district Muzaffarabad, Azad Jammu and Kashmir, Pakistan.

The Indian crested porcupine (Hystrix indica) is a vertebrate pest of agricultural lands and forest. The study was aimed to report the damage to local crops by the Indian crested porcupine (Hystrix indica) in the Muzaffarabad District. A survey was conducted to identify the porcupine-affected areas and assess the crop damage to the local farmers in district Muzaffarabad Azad Jammu and Kashmir (AJK) from May 2017 to October 2017. Around 19 villages were surveyed, and a sum of 191 semi-structured questionnaires was distributed among farmers. Crop damage was found highest in village Dhanni where a porcupine destroyed 175 Kg/Kanal of the crops. Regarding the total magnitude of crop loss, village Danna and Koomi kot were the most affected areas. More than half (51.8%) of the respondents in the study area suffered the economic loss within the range of 101-200$, and (29.8%) of the people suffered losses in the range of 201-300$ annually. Among all crops, maize (Zea mays) was found to be the most damaged crop ranging between 1-300 Kg annually. In the study area, porcupine also inflicted a lot of damages to some important vegetables, including spinach (Spinacia oleracea), potato (Solanum tuberosum) and onion (Allium cepa). It was estimated that, on average, 511Kg of vegetables are destroyed by porcupine every year in the agricultural land of Muzaffarabad. It was concluded that the Indian crested porcupine has a devastating effect on agriculture which is an important source of income and food for the local community. Developing an effective pest control strategy with the help of the local government and the Wildlife department could help the farmers to overcome this problem.

Foliar Fertilization by the Sol-Gel Particles Containing Cu and Zn

Silica particles with the size of 150-200 nm containing Ca, P, Cu or Zn ions were synthesized with the sol-gel method and tested as a foliar fertilizer on three plant species: maize Zea mays, wheat Triticum sativum and rape Brassica napus L. var napus growing on two types of soils: neutral and acidic. The aqueous suspensions of the studied particles were sprayed on the chosen leaves and also on the whole tested plants. At a specific stage of plant development determined according to the BBCH (Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie) scale, the leaves and the whole plants were harvested and dried, and the content of Cu and Zn was determined with the AAS (atomic absorption spectroscopy) method. The engineered particles were compared with a water solution of CuSO4 and ZnSO4 (0.1%) used as a conventional fertilizer. In many cases, the copper-containing particles improved the metal supply to plants more effectively than the CuSO4. The zinc-containing particles had less effect on both the growth of plants and the metal concentration in the plants. All the tested particles were not toxic to the examined plants, although some of them caused a slight reduction in plants growth.

Allelopathic Effects of Schima khasiana and Michelia champaca on Germination and Growth of Some Legume and Cereal Crops of North Eastern Himalayan Region

Allelopathic influences of Michelia champaca and Schima khasiana were tested in bioassay on two cereal crops (maize-Zea mays and paddy-Oryza sativa), and two legume food crops (rice bean- Vigna umbellata and soybean- Glycine max). The aqueous leaf extracts of fresh dried leaves of above tree species suppressed the growth of test crops. The study revealed that Michelia champaca and Schima khasiana are least toxic to germination, growth and yield of various test crops. Although, germination and growth of paddy and soybean was adversely affected by aqueous extracts of tree species, however, magnitude of toxicity was very less which is evident from the dry matter production of various test crops. Rice bean and maize have been found resistant to phytotoxicity. It is therefore; well evident from the data that maize, paddy, rice bean and soybean can be grown successfully in the proximity of Michelia champaca and Schima khasiana.

Entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae play roles of maize (Zea mays) growth promoter

Beauveria bassiana and Metarhizium anisopliae are two of the most important and widely used entomopathogenic fungi (EPFs) to control insect pests. Recent studies have revealed their function in promoting plant growth after artificial inoculation. To better assess fungal colonization and growth-promoting effects of B. bassiana and M. anisopliae on crops, maize Zea mays seedlings were treated separately with 13 B. bassiana and 73 M. anisopliae as rhizosphere fungi in a hydroponic cultural system. Plant growth indexes, including plant height, root length, fresh weight, etc., were traced recorded for 35 days to prove the growth promoting efficiency of the EPFs inoculation. Fungal recovery rate (FRR) verified that both B. bassiana and M. anisopliae could endophytically colonize in maize tissues. The recovery rates of B. bassiana in stems and leaves were 100% on the 7th day, but dropped to 11.1% in the stems and 22.2% in the leaves on the 28th day. Meanwhile, B. bassiana was not detected in the roots until the 28th day, reaching a recovery rate of 33.3%. M. anisopliae strains were isolated from the plant roots, stems and leaves throughout the tracing period with high recovery rates. The systematical colonization of B. bassiana and M. anisopliae in different tissues were further corroborated by PCR amplification of fungus-specified DNA band, which showed a higher detection sensitivity of 100% positive reaction. Fungal density comparing to the initial value in the hydroponic solution, dropped to be well below 1% on the 21st day. Thus, the two selected entomopathogenic fungal strains successfully established endophytic colonization rather than rhizospheric colonization in maize, and significantly promoted its growth in a hydroponic cultural system. Entomopathogenic fungi have great application potential in eco-agricultural fields including biopesticides and biofertilizers.

Genetic diversity of eight maize (Zea mays) cultivars from East Nusa Tenggara (Indonesia) based on inter simple sequence repeat markers

Abstract. Yani A, Chasani AR, Daryono BS. 2022. Genetic diversity of eight maize Zea mays L. cultivars from East Nusa Tenggara based on inter simple sequence repeat markers. Biodiversitas 23: 4124-4130. East Nusa Tenggara (NTT) is one of Indonesia's island that has many local maize cultivars. However, the existence of this local corn is threatened by the presence of high-yielding maize seeds. Therefore, characterization of local maize cultivars using molecular marker is needed to conserve the germplasm. This study aims to determine the genetic diversity of local maize cultivars (Zea maysL.) from East Nusa Tenggara based on ISSR markers. This research used eight local maize cultivars (Watar Ohaq, Watar Puluq, Wata Bura, Wata Kuma, Wata Bunga, Pena Muti, Boti Pulut, and Latun Wara). Young leaves of maize were used for DNA isolation. Total genomic DNA was isolated using Genomic DNA Mini Kit for Plant (Geneaid). DNA was then amplified using 5 ISSR molecular markers (ISSR-807, ISSR-808, UBC-809, UBC-811, UBC-834). DNA band profiles were scored based on the presence or absence of bands. Genetic variability was analyzed based on the UPGMA method using the MVSP ver application. 3.1. Local maize from NTT has high genetic diversity (similarity index between 0.29-0.65). Local maize cultivars were separated into two main clusters at a similarity index of 0.43 and the grouping pattern was not influenced by the geographic location of local maize origin.

Oviposition preference and development of the parasitoid Chelonus insularis on host fed on Zea mays and the teosinte Z. luxurians from Oaxaca, Mexico

ABSTRACT This study evaluated the oviposition preference and development of the parasitoid Chelonus insularis (Hymenoptera: Braconidae) on Spodoptera frugiperda (Lepidoptera: Noctuidae) fed on maize Zea mays and the teosinte Z. luxurians from Oaxaca, Mexico. For the oviposition preference test, an unmated and naïve C. insularis female, and egg masses of S. frugiperda that in the larval stage were fed on maize or teosinte were used. The experiment was repeated 52 times in paired treatments. For the development of C. insularis, 178 larvae of S. frugiperda were fed on maize and 159 larvae on teosinte. Chelonus insularis did not distinguish between eggs from hosts fed on maize or teosinte. The development of parasitoid on maize and teosinte was similar, except for the period of time from oviposition to adult emergence, with 24.24 and 26.51 d, respectively. Parasitism of S. frugiperda eggs was greater than 77%. Larval survival rate was greater than 93% and pupal rate greater than 74%. The emergence of healthy adults varied between 76 and 91% and the sex ratio was biased to males.

Linkage mapping combined with GWAS revealed the genetic structural relationship and candidate genes of maize flowering time-related traits

BackgroundFlowering time is an important agronomic trait of crops and significantly affects plant adaptation and seed production. Flowering time varies greatly among maize (Zea mays) inbred lines, but the genetic basis of this variation is not well understood. Here, we report the comprehensive genetic architecture of six flowering time-related traits using a recombinant inbred line (RIL) population obtained from a cross between two maize genotypes, B73 and Abe2, and combined with genome-wide association studies to identify candidate genes that affect flowering time.ResultsOur results indicate that these six traits showed extensive phenotypic variation and high heritability in the RIL population. The flowering time of this RIL population showed little correlation with the leaf number under different environmental conditions. A genetic linkage map was constructed by 10,114 polymorphic markers covering the whole maize genome, which was applied to QTL mapping for these traits, and identified a total of 82 QTLs that contain 13 flowering genes. Furthermore, a combined genome-wide association study and linkage mapping analysis revealed 17 new candidate genes associated with flowering time.ConclusionsIn the present study, by using genetic mapping and GWAS approaches with the RIL population, we revealed a list of genomic regions and candidate genes that were significantly associated with flowering time. This work provides an important resource for the breeding of flowering time traits in maize.

Toxicometabolomic profiling of resistant and susceptible western corn rootworm larvae feeding on Bt maize seedlings

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is the most serious pest of maize (Zea mays L.) in the U.S. Corn Belt and parts of Europe. Transgenic maize hybrids expressing at least one of the four currently available insecticidal toxins from Bacillus thuringiensis (Bt) Berliner, currently the most widely adopted control method in continuous maize, have faltered due to the emergence of resistance. The resistance mechanisms of WCR to Bt toxins are not fully understood. We identified metabolic profiles of susceptible and resistant WCR larvae fed on maize hybrids expressing each of three available Cry3 proteins (eCry3Ab1, mCry3A, and Cry3Bb1) targeting corn rootworms and a control non-Bt maize via an untargeted metabolomics approach. Over 580 unique metabolites found in WCR larvae were classified into different pathways (amino acids, carbohydrates, cofactors and vitamins, energy, lipid, nucleotide, peptide, and xenobiotics). By exploring shifts in WCR larval metabolome exclusively by Bt toxins, several candidate metabolites and metabolic pathways were identified in susceptible and resistant larvae that may be involved in defense against or recovery from Bt ingestion by these larvae. These findings would provide mechanistic insights into altered metabolic pathways associated with the resistance mechanisms of WCR to Bt toxins.

SCREENING OF MAIZE (Zea mays L.) FOR PHYTOREMEDIATION ON CRUDE OIL CONTAMINATED SOIL

This study aimed at determining the phytoremediation latent of maize (Zea mays) on crude oil-contaminated soil. It involved the collection of maize seeds and growing it on a simulated oil spill contaminated soil with treatments at 25%, 50% and 75% w/w crude oil, alongside a control group. The experimental design was randomized; having three replicates, and was observed for fourteen days. Germination and growth parameters such as number of leaves, height of plant and stem girth was observed, and recorded. The result confirmed that crude oil had effects on the increase limit. The highest height recorded for the control with mean height of 57.85cm. The control group had mean value of 7.41 as the utmost quantity of leaves. The 25g treatment group recorded 8.62cm2, which was the highest recorded stem girth, followed by the control with mean value of 8.18cm2. From the soil analysis the metal status examined in the control group varied significantly from the crude oil contaminated soil. However, the study proves that the plant has phytoremediation capacity and hence can be utilized in phytoremediation of crude oil polluted soil

Effects of Stand Density and N Fertilization on the Performance of Maize (Zea mays L.) Intercropped with Climbing Beans (Phaseolus vulgaris L.)

Maize is Germany’s most important fodder and energy crop. However, pure maize cultivation has ecological disadvantages. Moreover, its yield is low in crude protein, an important feed quality parameter. Maize–bean intercropping can potentially address both issues. A bean variety specially developed for intercropping was first introduced in 2016. Using this variety, a network of institutions conducted 13 field trials from 2017 to 2020 on four sites in Germany. We sought to determine the effects of stand density and nitrogen (N) fertilization on dry matter yield, crude protein yield, and soil mineral N content (Nmin) at harvest of intercropped vs. pure maize. The three intercropping bean densities we tested (7.5, 5.5, and 4 plants/m2) produced non-significantly different yields of dry matter or crude protein, given a maize density of 7.5–8 plants/m2. Intercropping was inferior to pure maize in dry matter yield, but non-significantly different in crude protein yield. Under neither cropping strategy were significant losses in dry matter or crude protein yield recorded with reduced compared to full N fertilization. At full fertilization, however, both pure maize systems and the 8/4 maize–bean intercrop system left significantly higher Nmin at harvest than the other variants of the corresponding system or N fertilization level and thus an increased risk of nitrate leaching. We encourage further optimization of yield performance in maize–bean intercropping, e.g., through breeding or promotion of biological N fixation via rhizobia inoculation. Furthermore, we recommend reducing N fertilization levels in maize cultivation.

Mathematics of the Relationship between Plant Population and Individual Production of Maize (Zea mays L.)

Predominantly, field experiments aim to determine the optimal plant density for a unit area. High spatial variation results in lower attained yield than the genetic potential. To find the highest value of the product of mean individual production and crop density, their mathematical relationship is needed to be known. In this study, the relationship between the population and the weight of the individual fresh, dehusked ear of grain maize (Zea mays L.) was investigated, and a relevant mathematical simulation model was developed. Linear regression was disproved to describe this relationship properly based on the analysis of different mosaic sizes within a plot. The distribution of plant-to-plant distance was found to be binomial. The distribution of the ear weight was found to be lognormal. For the description of the population homogeneity, neither the standard deviation nor the variation coefficient was found to be applicable apart from the scale-independent relative variance. The simulation model, based on the above statistical functions, was validated with a real dataset, and it is recommended for the optimization of the plant population at farm scale.

Overyielding is accounted for partly by plasticity and dissimilarity of crop root traits in maize/legume intercropping systems

Abstract Positive biodiversity–productivity relationships have been found in biodiversity field experiments of grasslands, forests and natural terrestrial ecosystems, where diversity effects were separated by complementarity (CE) and selection effects (SE). However, we know little about how CE and SE are related to root traits and root dissimilarity. A 4‐year field experiment was carried out with a split‐plot design, where main plot was four nitrogen (N) applications (N0, N1, N2 and N3) and five cropping systems (maize Zea mays L./soybean Glycine max L. Merrill., maize/peanut Arachis hypogaea L. intercropped and the corresponding monocultures) with three replicates. Roots were sampled in the N0 and N2 treatments in 2 years. Intercropping effects were analysed based on grain yield for 4 years and roots were sampled down to 60 cm depth, and analysed with morphological parameters at different crop growth stages in 2 years. Intercropping significantly increased grain yield and above‐ground biomass in both intercropping systems under all N treatments. The partitioning of the net intercropping effects showed that yield advantage in intercropping was due to a positive CE under the N0 treatment, and to a positive SE with N application. Maize showed greater root morphological plasticity than the legumes did, with greater changes in root length density (RLD), root weight density (RWD) and total root surface (TS) in intercropping than in monoculture. Intercropped maize occupied a larger soil space, while lateral RLD distribution of legumes was decreased by maize. The RLD, RWD and TS of intercropped maize were constant or increased in later growth stages. SE showed a significantly positive relationship with root dissimilarity. Principal component analysis showed mean root depth and specific root length of legumes drove the positive CE in the absence of N fertilization. Root dissimilarity determined by maize explained the selection effects in overyielding. Complementarity effects under N0 were closely associated with specific root traits such as mean root depth and specific root length. Linking changes of root traits with intercropping effects above‐ground helps understand yield advantages in diverse agroecosystem. In general, a cereal species with strong phenotypic plasticity intercropped with a legume species with strong physiological plasticity can maximize the yield advantage of intercropping. Read the free Plain Language Summary for this article on the Journal blog.

Aflatoxin and molecular characterization of isolates from stored food in some selected Local Government in Ekiti State

Aflatoxins are secondary metabolites produced by fungi species from the genus Aspergillus, notably A. flavus, A. parasiticus and A. nomius, which develop naturally in food products and tend to cause wide array of toxic effects in several animal species, including humans. Aflatoxins are typically reported in dry food commodities such as cereals, spices, and dry fruits. This research was conducted in Ido-Osi, Efon, and Emure Local Government Areas in Ekiti State, Nigeria. Three samples; Local rice (Oryza sativa L), Maize (Zea mays) and Groundnut (Arachis hypogaea L) were obtained from three popular markets from each local government. About 10 grains of each sample were selected at random into separate petri plates and surface sterilized in 1% hypochlorite for 3 minutes. The grains were rinsed several times with distilled water. The organisms associated with the samples were isolated using Direct plating method while the aflatoxin content was determined using ELIZA. The result showed the occurrence of five (5) different fungal species distributed among the stored foods. These include: Aspergillus spp., Rhizopus spp. Penicillium spp. Mucor spp. and Botrytis spp. The species determination was confirmed by PCR with the primers specific for the ITS-rDNA region sequencing. The organisms were confirmed to the species level to be; Aspergillus flavus and Trichoderma viridie. Aflatoxin B1 was present in all the samples in which sample 6 has the highest values of 240ppb while aflatoxin B2 was relatively low. The prevalence of Aspergillus flavus in the stored foods is above 50%, which is very high and indicate the possible highlevel production of aflatoxin in food samples under study.

EFFECT of digestates derived from the fermentation of maize-legume intercropped culture and maize monoculture application on soil properties and plant biomass production

BackgroundThe use of maize-legume mixed culture to produce renewable energy and fertilizers by anaerobic fermentation (AD), while respecting soil quality is a favourable approach in sustainable farming. This paper investigates how the substrate (silage) composition affects the quality of digestate and thus its effect on selected soil parameters (respiration, content of carbon and nitrogen). The high content of remaining nutrients (mainly N) in the AD residual biomass of digestate may increase the biomass of amended plants. One objective of this study was to determine the composition of different digestates produced by anaerobic fermentation of the biomass of intercropped (mixed) cultures. Other objectives focused the digestate impact on soil properties and yield of tested plant (lettuce) in a pot experiment, carried out under controlled conditions in the growth chamber for 6 weeks. Variants tested in the pot experiment included negative control, maize (Zea mays L.) digestate, broad bean (Vicia faba L.) digestate, white lupine (Lupinus albus L.) digestate, maize + broad bean digestate, maize + white lupine digestate.ResultsAs compared to maize, silage from the mixed culture (or legumes) positively affected the properties of digestate (content of N, P, K, Acid Detergent Fibre (ADF), Neutral Detergent Fibre (NDF), Acid Detergent Lignin (ADL). The effect of digestate application on soil parameters depended on the digestate composition: the highest basal respiration was induced by digestates with the increased content of dry matter and ADF – maize + broad bean and white lupine. The broad bean variant showed glucose-induced respiration 0.75 (μg CO2·g-1 h-1), while the lowest value was in the maize variant (0.45 μg CO2·g-1 h-1). The application of digestate derived from the mixed culture increased the plant biomass more than that of single maize silage digestate (+ 14% in the maize + broad bean variant and + 33% in the maize + white lupine variant).ConclusionsA potential was found of silage made of leguminous plants to increase the digestate N content. Nevertheless, it is desirable to increase the C/N ratio by raising the amount of C containing substances. Fertilization with digestate showed a potential to increase the plant biomass (compared to the unfertilized control); however, differences among the individual digestates were not observed. The benefit of legume added to the maize-based silage was proven, especially the contribution of nutrients to arable soil.Graphical abstract

Evaluation of root lodging resistance during whole growth stage at the plant level in maize

Root lodging due to strong storm wind is a common problem in maize (Zea mays) production, leading to reduced crop yield and quality and harvest efficiency. Little information is available on quantifying effects of vertical leaf area distribution on root lodging in crops such as maize. Anti-lodging index of root was computed by the formula: ALroot = Mroot / Mwind, where AL denotes anti-lodging index, and M moment of force. Mroot, root failure moment of force equals to moment arm times max root side-pulling force measured in situ by means of the digital pole dynamometer, and Mwind, wind resultant moment of force is estimated with vertical leaf area distribution and wind speed. Two maize cultivars were examined at 5 different growth stages from V8 to physiological maturity in 2019 and 2020, in Qingdao, China. Root anti-lodging index in tested cultivars fluctuated to a small extent within any year during whole growth period excluding at V8, while there was an inter-annual shift in index means (1.23 vs 0.84). Both root failure moment and wind resultant moment increased first and then decreased with the growth stage, and their influences on root anti-lodging index varied with the year. At wind grade 6, effect sizes, as contribution to root anti-lodging index, of root moment and wind moment were respectively 0.88 and 0.98. The difference in anti-lodging index between cultivars seemed to be disappearing as wind grade goes up. Root failure moment of force positively related to single root tensile resistance, root-soil ball volume, root number and total root length, whose correlation coefficient was the maximum of 0.94. Root anti-lodging index of maize proved stable from V8 on during whole growth period, and vertical leaf area distribution played a substantial role in maize root lodging in terms of wind resultant moment. Our findings provide the insights into root lodging events in crops such as maize, and would serve an approach to assessing crop root lodging resistance in breeding and cultivation programs.

Gene expression variation explains maize seed germination heterosis

BackgroundHeterosis has been extensively utilized in plant breeding, however, the underlying molecular mechanism remains largely elusive. Maize (Zea mays), which exhibits strong heterosis, is an ideal material for studying heterosis.ResultsIn this study, there is faster imbibition and development in reciprocal crossing Zhengdan958 hybrids than in their parent lines during seed germination. To investigate the mechanism of heterosis of maize germination, comparative transcriptomic analyses were conducted. The gene expression patterns showed that 1324 (47.27%) and 1592 (66.44%) of the differential expression genes between hybrids and either parental line display parental dominance up or higher levels in the reciprocal cross of Zhengdan958, respectively. Notably, these genes were mainly enriched in metabolic pathways, including carbon metabolism, glycolysis/gluconeogenesis, protein processing in endoplasmic reticulum, etc.ConclusionOur results provide evidence for the higher expression level genes in hybrid involved in metabolic pathways acting as main contributors to maize seed germinating heterosis. These findings provide new insights into the gene expression variation of maize embryos and improve the understanding of maize seed germination heterosis.

Nutritional quality, functional property and acceptability of maize (Zea mays) based complementary foods enriched with defatted groundnut (Arachis hypogea L.) and ginger (Zinger officinale Roscoe) powder in Wistar rats

Traditional complementary foods in Africa are cereal-based, low in nutrient-density; hence, causing severe-acute-malnutrition. This study was aimed to formulate and evaluate nutritional quality of complementary foods (CF) using locally available food materials. Yellow maize (raw, germinated & fermented), defatted groundnut (DGF) and ginger flour (GGF) were blended to obtain RDG (76.7% raw yellow maize, 20.8% DGF and 2.5% GGF), GDG (74.4% germinated yellow maize, 23.1% DGF, 2.5% GGF), and FDG (72.6% fermented yellow maize, 24.9% DGF, 2.5% GGF). Food samples were evaluated for nutritional qualities and sensory attributes using standard methods. Protein (g/100 g), energy value (kCal/100 g), total amino acids and essential amino acids (g/100 g protein) of formulated CF ranged from 19.38 to 28.58, 373.49 to 394.53, 87.33 to 91.89 and 36.17 to 37.63, respectively, and were comparable to control (17.07, 401.22, 94.47 & 35.35). Minerals were present in appreciable amount in the foods, while phytate/mineral (Ca, Fe, Zn) and oxalate/calcium molar ratios were lower than critical levels. Bulk density (1.4 - 1.6 g/mL), least gelation (4 - 6%), water absorption capacity (10.5 - 15.8%) and swelling capacity (0.5 - 1.2%) were significantly (p < 0.05) lower in formulated CF than in control, except for bulk density. Biological value (78.44%) of FDG was significantly (P < 0.05) higher than GDG (78.4%) and RDG (75.87%), respectively, but lower than control (93.48%). Pack cell volume (22.50%), haemoglobin concentration (7.5 g/dL), red blood cell (3 × 103 mm− 3), albumin (3.72 g/dL), total blood protein (5.62 g/dL) and globulin (1.9 g/dL) of rats fed on FDG were significantly (p < 0.05) higher than other diets, but comparable to that of control. Kidney (urea, 10.16 mg/dL; creatinine, 4.8 mg/dL) and liver function index (AST/ALT ratio, 0.38) of rats fed on FDG were lower than in those rats fed on RDG, GDG and control. For sensorial attributes, RDG was ranked best next by FDG in appearance, aroma, texture, taste and overall acceptability, but were significantly (p < 0.05) rated lower than control. Finally, the study established that FDG (72.6% fermented yellow maize, 24.9% defatted groundnut and 2.5% ginger) was the best in nutritional quality and growth performance in rats; hence, this CF may be suitable to mitigate expensive commercial infant formula in alleviating severe-acute-malnutrition in children.Graphical abstract