Quality Of Maize Grains Research Articles

Identifying key drivers for geospatial variation of grain micronutrient concentrations in major maize production regions of China

Micronutrient deficiencies are prevalent health problems worldwide. The maintenance of adequate concentrations of micronutrients in maize grain is crucial for human health. We investigated the overall status and geospatial variation of micronutrients in Chinese maize grains and identified their key drivers. A field survey was conducted in four major maize production areas of China in 2017 with 980 pairs of soil and grain samples collected from famers’ fields. At a national scale, grain zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) concentrations varied substantially, with average values of 17.4, 17.3, 4.9, and 1.5 mg kg−1, respectively, suggesting a solid gap between grain Zn and Fe concentrations and the biofortification target values. Significant regional difference in the concentrations of Zn, Mn and Cu, but not Fe, were observed in grain, with much higher levels in Southwest China. The nutritional yields of Zn, Fe and Cu were lower than the energy and Mn yields, indicating an unbalanced output between energy and micronutrients in current maize production system. Grain Zn, Fe, Mn and Cu correlated negatively with maize yield in most test regions. Increased nitrogen (N) rate positively affected grain Zn and Cu, while increased phosphorus (P) rate negatively affects grain Zn and Fe. Apart from Fe, available Zn, Mn and Cu in soil exerted significant positive effects on grain Zn, Mn and Cu concentrations, respectively. Decrease in soil pH and increase in the organic matter content may increase the accumulation of Fe and Mn in grain. Grain Zn and Cu concentrations increased as available soil P decreased. Of the factors considered in this study, grain yield, N and P rates, soil pH and organic matter were the main factors that affect grain micronutrient status and should be more extensively considered in the production and nutritional quality of maize grain.

Assessment of heavy metal(loid)s contamination risk and grain nutritional quality in organic waste-amended soil

Studies that evaluate the human health risk of heavy metal(loid)s pollution have not been widely performed for organic waste-amended soils on the Loess Plateau of China. With this respect, we conducted a 3-year field trial to estimate the heavy metal(loid)s contamination of soil and maize, the resultant nutritional quality of maize grains and the health risk under treatments of conventional fertilizer (CF), traditional Chinese medicine residue (TCMR) and sheep manure (SM). We found that protein, amino acids and lysine in maize grains were increased by 12.3, 11.3 and 5.88 % under TCMR treatments relative to SM application, respectively. Meanwhile, this treatment reduced the levels of Cr, Pb, Cd, As and Hg in soil and maize grains. All fertilization regimens resulted in greater health risks for children, with HI values ranging from 1.06 to 1.52 and CR levels for Cr and As being ﹥1.0 × 10−4, especially higher in SM treatments. This presented the beneficial effect of TCMR than SM. The further investigated of toxic metal(loid)s level in SM and its application risks, based on meta-analysis and Monte Carlo simulation, indicated Cd, Hg and Pb were the most cautionary heavy metal(loid)s and contamination risk were greater on the southwest regions of China.

Combined Application of Potassium and Zinc Improves Water Relations, Stay Green, Irrigation Water Use Efficiency, and Grain Quality of Maize under Drought Stress

Maize (Zea mays L.) plays an important role in the global food security, but its production is threatened by climate change, especially drought stress. Potassium (K) and zinc (Zn) are considered useful to mitigate the negative consequences of drought stress in plants. Therefore, the objective of this two-year study was to identify the best combination of K and Zn application to improve the water relations, photosynthetic pigments, yield, irrigation water use efficiency (IWUE) and grain quality of maize sown under mild and severe drought stress conditions. The consisted of three drought stress levels viz. 1) well-watered as control (WW), 2) mild drought (MD) with 25 mm of potential soil moisture deficit (PSMD), 3) severe drought (SD) with 50 mm of PSMD and six K-Zn treatments: i.e. 125, 100 and 150 kg ha−1 K with 0 and 12 kg ha−1 Zn. The results indicated that K-Zn application improved the water relations and chlorophyll contents, biological yield and grain quality, irrespective of water stress treatment. The combined application of K-Zn under mild drought stress produced statistically same biological yield and grain quality as under well-irrigated without K-Zn fertilization and also produced compratively higher IWUE, biological yield and grain quality under sverer drought stress. Hence, the application of K at 150 kg ha−1 in combination with Zn at 12 kg ha−1 might be useful to improve the maize production and grain quality under drought stress. As IWUE was low in WW conditions, therefore, irrigation scheduling must be re-evaluated for optimum water use efficiency.

Transcriptome analysis of maize seedling roots in response to nitrogen-, phosphorus-, and potassium deficiency

Soil deficiencies with respect to the availability of macronutrients such as nitrogen, phosphorus, and potassium seriously affect the growth, yield, and grain quality of maize (Zea mays L.). To improve the utilization efficiency of mineral elements in maize, we wanted to find the key genes that regulate the growth of maize roots under nutrient-deficient conditions. Maize plants were subjected to nitrogen, phosphorus, and potassium deficiency stress and their roots were collected and analyzed using transcriptome sequencing. GO and KEGG analyses of the differentially expressed genes (DEGs) were performed, and qPCR was used to verify the reliability of the transcriptome data. When maize was subjected to any of the three nutrient-deficiencies mentioned in Methods, the growth and root vitality of its roots were inhibited. 1255, 1082, and 324 genes specifically expressed when the maize was subjected to N, P, and K deficiencies, respectively, and all three treatments shared 575 DEGs. Genes that are associated with nutrient utilization, hormones, and transcription factors differentially expressed under different types of nutrient-deficiency stress. We speculated that MRP2, bZIP77, and bZIP53 play a positive regulatory role in maize root growth in an environment suffering from nutrient deficiencies. The molecular mechanism by which maize root growth responds to nutrient stress is complicated. NPF7.3, GlpT4, HAK24, and HAK5, MRP2, bZIP77, and bZIP53 can be used as candidates’ genes that regulate maize root growth under nitrogen, phosphorus, and potassium deficiency stress.

Tillage systems and nitrogen timings effect on growth, stay green and grain quality in maize (Zea mays L.)

Nitrogen (N), being mobile in soil is exposed to various losses owing to unwise use of nitrogen fertilizer, and conventional soil and crop management practices which can be minimized by temporal nitrogen application and different tillage practices. This study was conducted to elucidate the effect of different tillage systems and nitrogen timings on growth, stay green and grain quality in maize. Three tillage systems viz. T1: tillage with cultivator, T2: mouldboard plough + 2-cultivations, T3: chisel plough + 2-cultivations; and five nitrogen timings viz. N1: whole at sowing, N2: ½ at sowing+½ at V5 (5-leaf stage), N3: ½ at sowing+½ at tasseling, N4: ½ at V5+½ at tasseling, N5: 1/3 at sowing+1/3 at V5+1/3 at tasseling). Tillage systems and nitrogen application had significant effect on leaf area per plant, specific leaf area and leaf area ratio. Tillage systems had non-significant effect on stay green and grain quality parameters except for oil contents. However, nitrogen timings had significant effect on chlorophyll a, b and total contents as well as grain quality parameters. The higher a, b and total chlorophyll contents were noted with three splits i.e. 1/3 at sowing+1/3 at V5+1/3 at tasseling compared with other treatments. The results suggest to grow maize by preparing the field through chisel plough and applying N in three splits to improve its growth, chlorophyll contents and grain quality.

Physical quality of maize grain harvested and stored by smallholder farmers in the Northern highlands of Tanzania: Effects of harvesting and pre-storage handling practices in two marginally contrasting agro-locations

On-farm trials were conducted to investigate the effects of maize harvesting and handling practices of smallholder farmers on the quality of the produce before, and during storage in two contrasting agro-locations. Farmers harvested and prepared the crop according to local practices, and stored it in ordinary woven polypropylene bags for 30 weeks. Grain moisture, insect populations, insect-damage, moldy/diseased/discolored grain, rodent-damage, shriveled grain, broken grains, non-consumable grains, impurities, and overall losses were monitored. Moisture of the pre-stored grain ranged between 11.0 and 23.7% while the overall physical damage was 16.9 ± 6.2%. Late harvesting increased moldy/diseased/discolored grain two-fold while de-husking and drying practices increased the levels in early-harvested grain by factor of 2–3. Insect populations were >10 times higher in the cooler agro-location, and handling practices increased them by factor of 2–10. The interaction of agro-location, harvesting time and drying influenced the amount of grain that was unfit for human consumption. Pre-storage losses of 3.6–11.2% were determined, mainly as grade-outs. With storage, the quality of early-and late-harvested maize did not differ. However, the majority of examined parameters were distinct by agro-location. Moreover, secondary pests and the levels of shriveled and broken grain levels were also distinct by drying method, while moldy/diseased/discolored grain, non-consumable grain, and overall losses were distinct depending on whether the harvested cobs were de-husked or not de-husked before drying. The high levels of grade-outs at the pre-storage stage suggest that sorting should be emphasized for quality improvement at the farm gate not only for the market but also household nutrition. Cultivation of varieties with superior maturing and post-harvest traits would lower the sorting losses. Agro-location and farmer practices influenced grain quality and magnitude of losses during storage. These findings should inform choice of intervention steps right from the pre-storage stage.

Evaluating the Quality of Maize Grains Stored in a Modified Metallic Silo

Maize is known to be an important crop for food security in developing countries; and farmers have continued to experience post-harvest losses which lead to reduction in the quality or quantity of maize grains. The main causes of post-harvest losses are the storage insect, pests, improper drying and poor storage systems. Poor storage accounts for 5-10% loss and 5% loss is attributed to insect attacks. This research modified a one tonne metallic silo with the aim of studying the effects on moisture content and hectolitre weight of the maize grains. The moisture content was determined using moisture meter while the hectolitre weight was determined using extruded brass material. The study lasted for six months and analyses were carried out on the data collected using Duncan multiple range tests at 95% level of confidence. The moisture content was observed to reduce from 13.5% to 11.4% w.b while hectoliter weight which is the main determinant of the market value of the grain was observed to increase from 276 kg/ml to 288 kg/ml, this implies that there was increase in the cost value of the grain after six month of storage. The results showed that variations in moisture content along storage period were significant at (p ≤ 0.05).

Research on Quality of Maize Grain as a Result of the Application of an Innnovative System for Storing Grain Under Operating Conditions

Abstract This study analyses the results of research on the improvement of grain quality using a filling core in a grain silo. The research is a part of the research project aimed at developing an innovative system for drying and storing maize grain that, among other benefits, reduces grain damage. Two series were carried out: a control series, in which a chute was applied as the main element, and an operation series, in which a cascade chute was used for testing. The analysis conducted on the simulated operating conditions showed a 4-5-fold reduction in the amount of grain damaged following the application of the filling core compared with the control series. It has also been shown that a 6-meter cascade chute considerably decreases the velocity of the falling grain when loading the silo.

The DOF-Domain Transcription Factor ZmDOF36 Positively Regulates Starch Synthesis in Transgenic Maize.

Starch synthesis is a complex process that influences crop yield and grain quality in maize. Many key enzymes have been identified in starch biosynthesis; however, the regulatory mechanisms have not been fully elucidated. In this study, we identified a DOF family gene, ZmDOF36, through transcriptome sequencing analysis. Real-time PCR indicated that ZmDOF36 was highly expressed in maize endosperm, with lower expression in leaves and tassels. ZmDOF36 is a typical DOF transcription factor (TF) that is localized to the nucleus and possesses transcriptional activation activity, and its transactivation domain is located in the C-terminus (amino acids 227–351). Overexpression of ZmDOF36 can increase starch content and decrease the contents of soluble sugars and reducing sugars. In addition, abnormal starch structure in transgenic maize was also observed by scanning electron microscopy (SEM). Furthermore, the expression levels of starch synthesis-related genes were up-regulated in ZmDOF36-expressing transgenic maize. ZmDOF36 was also shown to bind directly to the promoters of six starch biosynthesis genes, ZmAGPS1a, ZmAGPL1, ZmGBSSI, ZmSSIIa, ZmISA1, and ZmISA3 in yeast one-hybrid assays. Transient expression assays showed that ZmDOF36 can activate the expression of ZmGBSSI and ZmISA1 in tobacco leaves. Collectively, the results presented here suggest that ZmDOF36 acts as an important regulatory factor in starch synthesis, and could be helpful in devising strategies for modulating starch production in maize endosperm.

Implementing the ‘dry chain’ during storage reduces losses and maintains quality of maize grain

Maize grain quality is dependent on seed moisture content as high seed moisture leads to attack of stored grain by pests and to contamination by aflatoxin. Dry Chain is an economically viable and environmentally friendly option to overcome these problems. Dry Chain implies an initial drying of a commodity to low moisture and maintaining the low moisture throughout the supply chain. The quality of maize grain was experimentally evaluated after 4 months storage at 8, 10, 12 and 14% seed moisture content (SMC) in traditional packaging materials (paper, woven polypropylene, jute and cloth) and in hermetic bags (Super Bags) at Faisalabad, Pakistan. Results revealed significant changes in moisture content of grain stored in traditional packaging materials with varying environmental relative humidity, but moisture contents remained stable and low in the hermetically-sealed bags. Grain stored in Super Bags with 8% and 10% moisture content maintained high germination (93% and 88% after 2 and 4 months storage, respectively) and high starch and crude protein content. Higher concentrations of malondialdehyde (a measure of oxidative damage) and aflatoxins were observed in seeds stored at 14% SMC in both the sealed Super Bags and traditional packaging materials. The main benefit of the hermetically-sealed bags was reduction in incidence of the lesser grain borer (Rhyzopertha dominica). Damage and storage losses caused by the borer over a period of 4 months were 10% higher in conventional storage bags. In conclusion, insect populations and associated storage losses, and deterioration of maize seed quality with respect to loss of germination, food reserves and increased aflatoxin contamination can be controlled by maintaining the Dry Chain through hermetic storage of maize grain at 8% and 10% SMCs.

How leguminous biomass can increase yield and quality of maize grain in tropical agrosystems

The aim of this study was to evaluate the effect of soil cover with a combination of tree leguminous on increasing grain yield, grain protein content, and maize protein yield. The experiment was conducted with 10 treatments: Leucaena leucocephala + Clitoria fairchildiana + urea (L+C+U); L. leucocephala + Acacia mangium + urea (L+A+U); Gliricidia sepium + C. fairchildiana + urea (G+C+U); G. sepium + A. mangium + urea (G+A+U); L. leucocephala + C. fairchildiana (L+C); L. leucocephala + A. mangium (L+A); G. sepium + C. fairchildiana (G+C); G. sepium + A. mangium (G+A); bare soil with urea (B+U); and a control with bare soil without mineral fertiliser. Differences between G+C+U and B+U, in the agronomic efficiencies, increase in N contents, increase in grain yield. To increase the protein yields in humid regions, leguminous are used to provide nutrients and improve the root environment rather than interacting antagonistically with the crops.

Soil physical properties, nitrogen uptake and grain quality of maize (Zea mays L.) as affected by tillage systems and nitrogen application

Soil compaction is a global issue pertaining to agricultural lands. The frequent use of farm machinery and field operations at the same depth are the major causes of soil compaction. The gradual increase in soil compaction deteriorates maize grain quality due to reduced nitrogen (N) uptake. Quality food production by reducing soil compaction is the need of time, which can be achieved through deep tillage and N management. In this study, three tillage systems viz. conventional tillage (using cultivator), tillage with mould board plough +2-cultivations (MBP), and tillage with chisel plough +2-cultivations (CP); and three nitrogen levels viz. 100, 150 and 200 kg ha–1 were used to evaluate their effect on soil properties, N uptake and grain quality in maize. Lower bulk density (1.41 Mg m–3), higher total porosity (0.47 m3 m–3) and higher nitrogen uptake (96.01 kg ha–1) was recorded under chisel plough (CP) compared with other tillage systems. Different N levels had significant effect on grain and total N uptake and grain quality, while soil properties remains unaffected. Higher N uptake was recorded with 200 kg ha–1 N application than other treatments. Similarly, 8.51% and 8.57% more grain protein contents were recorded with 200 kg ha–1 N during first and second year respectively. Unlike grain protein, starch and oil contents were negatively affected by N application being higher starch (71.7%) and oil contents (3.41%) with less N supply (100 kg ha–1). However, interaction effect of tillage and nitrogen levels was found non-significant for all studied parameters except for oil contents. Higher oil contents were recorded with MBP along with 100 kg ha–1 N application. Overall study indicated that deep ploughing with CP is important for maize to explore more soil area for nutrient uptake and N is also important for improving grain quality especially protein contents an important food constituent.

Effect of Growth Promoter Supplement on Yield and Grain Quality of Maize (Zea mays L.)

GROWTH promoters or biostimulants have been called for the supplements that contain nutrients, amino acids and plant extracts. One of them would be taken into consideration to increase the production of plants is the growth promoter VIUSID agro. To study the effect of VIUSID agro on the maize grain yield (ton ha-1) as well as grain quality, two field experiments were carried out in the experimental field of Agric. Res. Stat., Fac. Agric., Cairo Univ., Giza, Egypt in 2015 and 2016 seasons.With this aim, five maize cultivars (Namely, the single cross hybrids SC-30k9, SC-110, SC-30k8, the three way cross hybrid TWC-310 and the open-pollinated composite Cairo-1) were evaluated under four dosages, i.e., 0.0, 0.96, 1.44 and 2.0L ha-1 of foliar spraying of theVIUSID agro. Means under the dosage of 0.96L ha-1 of theVIUSID agro significantly exceeded the control by 26.19% for grain yield ha-1 (GYH), 8.89% for grain protein percentage (GP%), 45.39% for protein yield/ha, 3.14% for grain oil percentage (GO%), 40.44% for oil yield ha-1 (OYH) and 33.29% for carbohydrate yield/ha. It was concluded that increasing maize yield ha-1and grain quality in the present investigation could be achieved by applying the low dosage (0.96L ha-1) of VIUSID agro.

ORGANIC MAIZE: CHANGES IN AMINO ACID COMPOSITION

The aim of this study was to assess the bromatological quality and the content of essential amino acids in maize grains produced using two different cropping systems: organic and conventional. The experimental area was 4 hectares, divided into 2 hectares per system. In the conventional management, agrochemicals from conventional maize production were used. In the organic management, inputs permitted by the current Brazilian legislation on organic production were used. For each system, 10 plots of 9 m² each were established, from which experimental samples were harvested. The method described by Silva & Queiroz (2002) was used to determine bromatological quality. Near-infrared reflectance spectroscopy (NIRS) was used to quantify essential amino acids. A significant difference was found in the bromatological quality of maize grains. The conventional management provided greater crude protein content. Significant changes were also found in the following amino acids: methionine, threonine, arginine, isoleucine, leucine, valine, histidine, and phenylalanine, which showed lower levels in the organic management. The results confirm the need to determine food composition before diet formulation, since using preestablished food compositions probably leads to differences between what was formulated and what was actually given to poultry. The type of management influenced the quality of maize grains. The management of plant nutrition in the organic system should be refined to adequately supply nitrogen, thus improving bromatological and amino acid quality of the grains.

Effects of legume green manure on the physicochemical quality of maize grains (Zea mays L.)

Effects of legume green manure on the physicochemical quality of maize grains (Zea mays L.)

Biogas digestate – benefits and risks for soil fertility and crop quality – an evaluation of grain maize response

Abstract The agricultural usability of biogas digestate solids (BDS) as a soil amendment depends upon its impact on soil fertility and the content of minerals in the edible part of the grown crop. This hypothesis was verified in a series of field experiments with maize conducted between 2014 and 2016 at Brody, Poland. The two-factorial experiment consisted of the DBS application method (broadcast and row) and its rate: 0, 0.8, 1.6, 3.2 t ha–1. The post-harvest analysis of soil fertility showed that BDS can, at least partly, replace mineral fertilizers. The supply of N-NO3 to maize as a growth driving factor was significantly limited by a shortage of iron, potassium and, to some extent, magnesium. As recorded in 2016, the shortage of available Fe resulted in a low/pool of N-NO3, thus significantly decreasing the yield of grain. The shortage of K supply to grain created a pathway for the accumulation of other elements, including heavy metals. The disadvantage of the N-NO3 pool increase, due to the DBS application, was concomitant with the enhanced intake of cadmium and lead, which consequently exceeded their permissible concentration limits in grain. These unfavorable results of biogas digestate impact on the quality of maize grain can be ameliorated by incorporating zinc into the biogas type of soil amendment and keeping a sufficiently high level of available potassium and iron. The shortage of K can be partly overcome by a better sodium supply, however, its accumulation in grain results in an enhanced accumulation of cadmium and lead.

RESPONSE OF MAIZE PLANTS TO DIFFERENT N-SOURCES AND FOLIAR APPLICATION OF POTASSIUM HUMATE

Two field experiments were conducted at El-Kassasin Farm, Ismailia Governorate, Egypt, (30o 33 ״ 31 ׳ N-30°56 ״ 7 ׳ E, elev. 15.8 m) during the summer seasons of 2014 and 2015 on maize plants (c.v. single hybrid 30K8) grown on a sandy loam soil to study the effect of applying different sources of N-fertilization alone and in combination with foliar application of humate potassium on yield and its components and quality of maize grains. Different sources of N-fertilization caused significant increases in yield and its components and mineral uptake. Meanwhile, application of 50% N- mineral as ammonium sulphate (75kg N fed.-1) +50% organic N (75 kg N fed.-1) (5.3 t compost fed-1) achieved the highest values of all aforementioned parameters followed by the application of 100% of the recommended mineral N (150 kg N/fed.) then 100 % organic N (150 kg N fed.-1) (10.6 t compost fed-1), in a descending order. Spraying maize plants with potassium humate significantly enhanced plant growth, yield and its components as well as N, P and K uptake, total protein and oil in grains. In this respect, spraying plants with 4 L/fed potassium humate attained the superiority impacts comparing the other treatments. Hence, it can be concluded that fertilizing maize plants with 50% N- mineral (75 kg N fed.-1) +50% organic N (75 kg N fed.-1) (5.3 t compost fed-1) in combined with spraying plants at rate 4 L/fed potassium humate gave the highest values of yield and its components and NPK uptake as well as protein and oil content in grains as compared to other interaction treatments.

Effect of incorporation of crop residue and inorganic fertilizer on yield and grain quality of maize

A field experiment was conducted during 2014 at Universiti Putra Malaysia, Serdang, Malaysia, to evaluate the effect of incorporation of crop residues with supplemental inorganic fertilizers on yield and quality of maize crop. Treatments included an unfertilized control, incorporation of maize residue, soybean residue and a mixture of maize and soybean residue with and without phosphorus and potassium fertilizer and the use of a complete inorganic nitrogen, phosphorus and potassium fertilizer. Results showed that soybean and maize + soybean residue applied without inorganic fertilizers or with inorganic fertilizer (phosphorus and potassium) increased maize yield and enhanced grain quality of maize. However, incorporation of maize residue without supplemental inorganic fertilizer was ineffective in increasing grain cob yield (11,237 kg/ha) and grain quality ( 11.1% protein content, 10.9 o brix sugar content and 4.77% oil content) of the maize crop above that of control (10,323 kg/ha green cob yield, 8.30 % protein content, 9.00 o brix sugar content and 4.77% oil content). The application of soybean residue with supplemental phosphorus and potassium fertilizer gave maize yield (37,290 kg/ha) similar to that of the complete inorganic fertilizer treatment (36,500 kg/ha). Therefore, inorganic nitrogen fertilizer can be replaced with soybean residues without any reduction in maize yield and grain quality.

The Reaction of some Maize Hybrids, Created at ARDS TURDA, to Fusarium spp. Infection

The most important disease of maize in Romania are stalk and ear rot, which caused yield losses in average of 20%. The resistant hibrids represent one of the most efficient solution for reducing the field loses caused by Fusarium spp. on the maize (Nagy et al., 2006). Diseases caused by Fusarium spp. can affect the yield and grain quality of maize because of contamination with numerous mycotoxins produced by these fungi (Czembor et al., 2015). The purpose of this paper was to know more about the reaction of different maize hybrids to Fusarium and the evaluating the effect of ear rot on the yield ability and mycotoxins accumulation. The experiments carried out at ARDS Turda, during four years (2012-2015). The biological material was represented by 8 hybrids, from different maturity groups, tested in two infection conditions with Fusarium spp. (natural and artificial infections). The temperature and rainfalls of the four years of experiments corresponding to the vegetation of maize (april-september) are influenced favourably the pathogenesis of stalk and ear rot caused by Fusarium spp. and a good discrimination of the resistance reaction of genotypes. Fusarium ear rot has significantly affected production capacity and chemical composition of corn hybrids tested. In conditions of artificial infection with Fusarium spp. was a decrease in the content of starch, fat and increased protein content compared with artificially inoculated variants. The quantity of fumonizin B1+B2 has reached to 5630 μg/kg in conditions of artificial infection. There are negative correlations between production capacity and degree of attack of fusarium ear rot; depending on the reacting genotypes tested increasing disease causes production decrease. The response of maize hybrids to Fusarium infection is influenced by infection and climatic conditions. These factors affect production both in terms of quantity and quality and accumulation of mycotoxins.

Fungal contamination of maize grain samples with a special focus on toxigenic genera

In this study, the total fungal count and contamination with toxigenic fungi from Aspergillus, Fusarium and Penicillium genera of 127 maize grain samples collected from animal farms in subrbs of Belgrade area during 2012-2015, were determined. The total fungal count was determined using a dilution method, and standard mycological procedures were used to identify potential toxigenic fungi genera. In the tested samples of maize grains, the total fungal count was from 1 x 101 to 3 x 106 cfu g-1. No statistically significant differences between investigated years in regard to the mean total fungal count were determined. According to the Regulation on the quality of animal feed of the Republic of Serbia, the total fungal count above permitted limit (2 x 105 cfu g-1) was established in 9.52, 7.89, 20.69 and 55.56% tested samples in 2012, 2013, 2014 and 2015, respectively. Potentially toxigenic fungi from Aspergillus, Fusarium and Penicillim genera have been identified as the most common in all the samples. In most of the samples, based on the average value for the four-year period (2012-2015), Fusarium species (92.22%) have been identified, followed by the species of the genera Aspergillus (80.83%) and Penicillium (48.68%). A weak positive correlation was established between the moisture content of the samples and the total fungal count in 2012 (r=0.41), in 2013 (r=0.27) and in 2014 (r=0.36) and the medium positive correlation (r=0.61) in 2015. Based on the results of mycological analysis of grain maize it can be concluded that the test samples in a relatively large number did not meet the criteria of hygienic quality. Therefore, regular and continuous control of the mycological quality of maize grain as the most important nutrient in animal nutrition is necessary as a preventive measure to reduce and control contamination of grain with mycotoxigenic fungi.