Zea Maize Research Articles

Identification of Yeast Strains Isolated from Agricultural Soils for Releasing Potassium-bearing Minerals

ABSTRACTThirty-five yeast strains were isolated from soil samples that were collected from different locations in Upper Egypt. The purified isolates were screened for the release potassium from mica on Aleksandrov agar medium. Two yeast isolates (KSY-29 and KSY-33) showed an ability to solubilize potassium by inducing clear zones around their colonies. They were identified as Pichia anomala and Rhodotorula glutinis, respectively, based on PCR analysis of the ITSI-26S region that was amplified by NL1/NL4 species-specific primers. The amount of K released from muscovite mica in the broth culture of the yeast isolates was measured after 5, 10, 15 and 20 days of the incubation at 25°C. Both yeast isolates were very effective in releasing K of muscovite in broth culture, recording 8.11–13.21 μg/ml that were released from muscovite mica after 20 days of incubation. The inoculation of maize (Zea maize) plants with these yeast isolates under different K levels (25, 50 and 100% of recommended dose of potassium, RDK) as potassium sulfate was tested on growth and K uptake by these plants in the greenhouse. Significant increases (p < 0.05) in plant height, root and shoot dry weights as well as K uptakes by shoots and roots maize plants occurred through the inoculation with KSY-29 or KSY-33 isolates.

Nitrous Oxide Emission and Soil Carbon Sequestration from Herbaceous Perennial Biofuel Feedstocks

Core Ideas Adding N fertilizer increases N2O emission from perennial grasses managed as feedstock. Interseeding clover with perennial grasses reduced N2O emission and yield. Soil organic C storage under grasses may be inadequate to offset fertilizer‐induced N2O flux. Nitrogen management to optimize yield‐scaled N2O flux from established grasses is needed. No soil organic C storage occurred under no‐till corn–soybean rotation to offset N2O flux. Switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman) are potential bioenergy feedstocks. Perennial grasses managed as bioenergy feedstock require nitrogenous inputs, which can cause N2O emission and, thereby, alter their effectiveness to mitigate greenhouse gas (GHG) emission. Few studies have measured N2O emission from perennial grasses managed as feedstock. The objectives of this study were to compare N2O flux and soil organic C (SOC) storage between (i) grasses with legume companion crops or with nitrogenous fertilizer, (ii) two grass harvest times (autumn and spring), and (iii) perennial systems and corn (Zea maize L.)–soybean [Glycine max (L.) Merr.] (C–S) rotation, all without tillage. Nitrous oxide flux was measured from May 2009 to May 2012, and SOC was measured in 2000, 2006, and 2011. Big bluestem–clover (Dalea) and switchgrass–clover treatments had dramatically reduced annual N2O emissions and yield‐scaled emissions compared with the respective grasses with urea fertilizer. Cumulative N2O emission was 14 to 40% greater in the big bluestem‐spring and switchgrass‐spring treatments compared with respective autumn‐harvested treatments. The average cumulative emission in fertilized big bluestem and switchgrass treatments (18.5 kg N2O‐N ha−1) exceeded that of the C–S rotation (12.7 kg N2O‐N ha−1). The emission factor (EF) for fertilized grasses averaged 2.5%, corn averaged 1.05%, and C–S rotation averaged 1.9%. The SOC storage by perennial grasses was limited to 0 to 5 cm and thus may not be adequate to offset N2O emission. Nitrogen management refinement is recommended for herbaceous perennials to optimize biomass production and minimize N2O emission.

Pathogens of the European corn borer, Ostrinia nubilalis, with special regard to the microsporidium Nosema pyrausta

The European corn borer, Ostrinia nubilalis, is the most important pest insect of corn (Zea maize) in Germany, other European countries and historically in North America. However, in Europe only a few reports on naturally occurring biotic mortality factors are available. In the present review, an overview on pathogens including nematodes attacking O. nubilalis is compiled. The primary data were originally derived from long-term diagnostic studies on pathogens of arthropods carried out by the Institute for Biological Control, Darmstadt, Germany. These are updated with findings from the literature and supplemented with data from other pest insects of the same lepidopterous Crambidae family. The most important and most frequently found pathogens are the microsporidium Nosema pyrausta, the fungi Beauveria bassiana and to some extent also Fusarium spp., and the bacteria Bacillus thuringiensis and Serratia marcescens. Thus far, viruses have not been detected. Data on practical use of B. thuringiensis, B. bassiana and other fungi, N. pyrausta, and some nematodes for biological control of O. nubilalis are presented. Because of the importance of N. pyrausta as a population regulator of O. nubilalis, causing a chronic disease in larvae and adults, the current knowledge on the occurrence, biology, transmission, effects on the host insect, interactions with beneficial insects and field experiments is presented. These data are complemented with former, unpublished studies on the occurrence and incidence of N. pyrausta in some German and French O. nubilalis populations (Hessen, Baden-Wurttemberg, Alsace). The review clearly indicates that pathogens may play an important role as naturally occurring mortality factors of O. nubilalis which may also be used as biocontrol agents or within conservation biological control strategies.

Impacts of Priming with Silicon on the Growth and Tolerance of Maize Plants to Alkaline Stress.

Silicon (Si) has been known to augment plant defense against biotic and abiotic pressures. Maize (Zea maize L.) is classified as a Si accumulator and is relatively susceptible to alkaline stress. In this study, seeds of maize were grown in pots and exposed to various concentrations of Na2CO3 (0, 25, 50, and 75 mM) with or without 1.5 mM Si in the form of sodium metasilicate Na2O3Si.5H2O for 25 days. Alkaline-stressed plants showed a decrease in growth parameters, leaf relative water content (LRWC), and the contents of photosynthetic pigments, soluble sugars, total phenols and potassium ion (K+), as well as potassium/sodium ion (K+/Na+) ratio. By contrast, alkaline stress increased the contents of soluble proteins, total free amino acids, proline, Na+ and malondialdehyde (MDA), as well as the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in stressed plants. On the other hand, application of Si by seed-priming improved growth of stressed plants, which was accompanied by the enhancement in LRWC, and levels of photosynthetic pigments, soluble sugars, soluble proteins, total free amino acids and K+, as well as activities of SOD, CAT, and POD enzymes. Furthermore, Si supplement resulted in a decrease in the contents of proline, MDA and Na+, which together with enhanced K+ level led to a favorable adjustment of K+/Na+ ratio, in stressed plants relative to plants treated with alkaline stress alone. Taken together, these results indicate that Si plays a pivotal role in alleviating the negative effects of alkaline stress on maize growth by improving water status, enhancing photosynthetic pigments, accumulating osmoprotectants rather than proline, activating the antioxidant machinery, and maintaining the balance of K+/Na+ ratio. Thus, our findings demonstrate that seed-priming with Si is an efficient strategy that can be used to boost tolerance of maize plants to alkaline stress.

Voluntary Intake and Digestibility of Nutrients in Heifers Fed Hydroponics Maize (Zea mays L.) Fodder

Voluntary intake and digestibility of nutrients in heifers fed hydroponics maize (Zea maize L.) fodder was studied. Hydroponics maize fodder (HMF) was produced in a hydroponics chamber (greenhouse) measuring about 25 ft × 10 ft × 10 ft with a daily production potential of 600 kg fresh HMF and equipped with automatic sprayer irrigation by tap water. Four heifers (avg. BW 305 kg) were fed individually 2 kg standard conventional concentrate mixture along with 3 kg jowar straw and ad lib. HMF daily to meet their nutrient requirements for a period of 45 days followed by a 6-d digestion trial. The HMF looked like a mat of 20–30 cm height consisting of germinated seeds, white roots and green leaves. The increase in weight of the HMF than the seed weight on fresh basis was 5–6 folds. The DM content of the HMF was 15.4% and the CP, EE, CF, NFE and TA content was 13.56, 2.46, 8.98, 73.45 and 1.56% on DM basis, respectively. The DM intake per 100 kg BW of the heifers was 2.25 and the R: C ratio was maintained at 73: 27. The digestibility of DM, OM, CP, EE, CF and NFE of the ration was 65.62, 68.06, 69.36, 80.95, 59.70 and 69.87%, respectively. The total ration had 12.73% CP, 8.81% DCP and 68.71% TDN. It can be concluded that hydroponics maize fodder could be fed to heifers in situations where conventional fodder is not available or can not be grown due to any adverse conditions.

Effect of irrigation levels and agrochemicals on dry matter partitioning in summer maize (&lt;italic&gt;Zea maize&lt;/italic&gt; L.)

Application of eight irrigations (seedling, 6 leaf, knee-high, before tasseling, 50% tasseling, 50% silking, grain formation and grain filling stages) where no stress was occurred significantly increased dry matter distribution. Data related to dry matter partitioning in stem, leaves and cobs at 25, 50, 75 and at harvest stage of crop. In general, irrespective of the treatments, crop attained maximum leaf dry weight at flowering stage. This decreased progressively up to harvest stage. While, stem dry weight showed increasing trend up to tasseling and silking stage and than declined slightly towards harvest stage of the crop. Obviously, cobs dry weight increased linearly from flowering up to harvest stage.

Populerization of maize among the small farmers of Ernakulam district of Kerala through front line demonstration

To popularise maize crop (&lt;italic&gt;Zea maize&lt;/italic&gt;) among small farmers of Ernakulam district of Kerala, Krishi Vigyan Kendra, ICAR-Central Marine Fisheries Research Institute organised 25 demonstrations during 2012-13 to 2014-15 on traditional farmer’s field. Maize cultivars Pratap-4 and Pratap-5 were used for demonstration during January to May and September to December season. Farmers were motivated and trained for maize seed multiplication and cultivation aspects. Results of demonstration revealed that Pratap-4, Pratap-5 and local variety produced 33.70, 30.7 and 23.4 q/ha, respectively. Average income generated by the crop range from Rs. 40440/- to Rs. 36840/- and local variety Rs. 30240/-. Cost benefit ratio was 2.18, 1.99 and 1.77. for Pratap-4 , Pratp-5 and local variety, respectively. Technology index was reduced in the 2nd and 3rd year showed the feasibility of maize crop in the area. Thereafter, 500 farmers initiated the small scale farming of maize in the district with the technical guidance provided from KVK.

MANAGING NITROGEN REQUIREMENTS FOR MAIZE CROP GROWN ON SANDY SOIL USING FOLIAR APPLICATION OF NITROGEN AND ZINC WITH BIO-FERTILIZATION.

The integration among nitrogen mineral fertilization, foliar application of micronutrients and inoculation with bio-fertilizers become necessary to save mineral nitrogen fertilizers and increase the productivity of maize yield and its quality. As for, a field experiment was carried out during the two successive summer growing seasons 2013 and 2014 in sandy soil at El-Sharawy village in EL-Bostan area – Noubaria Region, Elbeheira governorate (Latitude 30° 43' 22.01 N, Longitude 30° 16' 44.50 E), to study the response of maize (Zea maize L.) yield and its components to mineral nitrogen fertilization rates as soil and foliar application and zinc-EDTA foliar application with bio-fertilizer. Treatments were carried out as split split plot design with three replicates; the main plots were bio-fertilizer without (Bio0) and with (Bio1); the split plots were two levels of Zn-EDTA foliar application, Zn0 (without foliar) and Zn1 ( with foliar 0.06 % Zn-EDTA), and the sub split plots were five rates of nitrogen fertilizer (N1: 100 % of recommended N (RN) fertilizer as soil application; N2:75 % RN + 1% N foliar at two times, N3: 75 % RN + 1% N foliar at three times, N4: 50 % RN + 1% N foliar at two times and N5: 50 % RN + 1% N foliar at three times). The most important results could be summarized as follows: Application of N-fertilization rates, foliar Zn-EDTA and inoculation with bio-fertilizer have a significant effects on all studied parameters such as plant height, ear weight/plant, grain and stalks yields, 100-grain weight, percentage of carbohydrate, oil and protein, concentrations and uptake of N, P, K and Zn by maize grain. Where, grain yield increased by 12.81% with bio-fertilizer inoculation and by 7.13% with Foliar Zn-EDTA. The interaction between zinc and bio-fertilizer significantly increased plant height, ear weight/plant, 100-grain weight, concentrations and uptake of phosphorus and zinc, also the interactions between N-rates and bio-fertilizer have significant effects on 100-grain weight, grain yield, concentrations and uptake of phosphorus and zinc. Moreover, the interaction between N-rates and foliar Zn-EDTA has significant effect on maize grain yield. Also, the interaction among N-rates, Zn and bio-fertilizer have significant effect on ear weight/plant, stalks yield, 100-grain weight, oil %, concentrations and uptake of N, K and Zn by grain. Whereas, the superiority was for interaction N3*Zn1*Bio1 that achieve the highest relative increase % for ear weight, grain and stalks yields, carbohydrate %, oil % and protein % (13.03, 27.82, 18.53, 4.14, 16.10 and 11.16 %, respectively).

Genomic variation in recently collected maize landraces from Mexico.

The present dataset comprises 36,931 SNPs genotyped in 46 maize landraces native to Mexico as well as the teosinte subspecies Zea maiz ssp. parviglumis and ssp. mexicana. These landraces were collected directly from farmers mostly between 2006 and 2010. We accompany these data with a short description of the variation within each landrace, as well as maps, principal component analyses and neighbor joining trees showing the distribution of the genetic diversity relative to landrace, geographical features and maize biogeography. High levels of genetic variation were detected for the maize landraces (HE = 0.234 to 0.318 (mean 0.311), while slightly lower levels were detected in Zea m. mexicana and Zea m. parviglumis (HE = 0.262 and 0.234, respectively). The distribution of genetic variation was better explained by environmental variables given by the interaction of altitude and latitude than by landrace identity. This dataset is a follow up product of the Global Native Maize Project, an initiative to update the data on Mexican maize landraces and their wild relatives, and to generate information that is necessary for implementing the Mexican Biosafety Law.

How land allocation and technology innovation affect the sustainability of agriculture in Argentina Pampas: An expanded life cycle analysis

Pampas region grows more than 80% of Argentina's main crops, with maize (Zea maiz L.), soybean (Glycine max L. Merr.) and wheat (Triticum aestivum L.) producing crop and landscape homogeneity that reduces biodiversity, agricultural system resilience and current and future regional welfare. With growing population and markets, there is a call for new agricultural patterns to meet increased food demand, together with concern for reducing environmental impact and improving social welfare. These challenges need rigorous approaches to measuring technological change costs and benefits as well as evaluating environmental impact of farmers' management practices. The objectives of this study are: [1] to evaluate resource use and environmental impact of current agricultural patterns in the northern part of Pampas region, [2] to contrast this with agricultural systems of previous decades, and [3] to analyze the incidence on space and time scales of the different proportions of land allocated to these three crops. Life cycle evaluations of cropping systems enlarge the scope of the analysis and help identify how problems might be solved. We utilize the SUMMA (SUstainability Multimethod Multiscale Assessment) framework for assessing the performance of integrated crop production in the northern Pampas in the years 1986–87, 1995–96, and 2009–10 based on actual land use data, compared to current systems with similar proportions of land distribution for the three crops, and to a wheat/soybean annual system. We also simulate other potential alternative land distribution scenarios. Results indicate a worsening of 9 to 12 out of 15 environmental indicators per unit of area (density of impacts), while there is an improvement per unit of product or income. The grain yield accounted in energy per hectare increased three times in relation to the year of reference (1986), while the energy demand decreased by 32%, blue water demand increased 50%. Acidification increased more than twice (7.99kgSO2eq./ha), while carbon emissions (982kgCO2eq./ha in 2009) decreased. These results provide a benchmark for further studies where new alternatives of crop distribution may prove environmentally and economically desirable choices for farmers in the Pampas.

Genomic affinities revealed by GISH suggests intergenomic restructuring between parental genomes of the paleopolyploid genus Zea.

The present work compares the molecular affinities, revealed by GISH, with the analysis of meiotic pairing in intra- and interspecific hybrids between species of Zea obtained in previous works. The joint analysis of these data provided evidence about the evolutionary relationships among the species from the paleopolyploid genus Zea (maize and teosintes). GISH and meiotic pairing of intraspecific hybrids revealed high genomic affinity between maize (Zea mays subsp. mays) and both Zea mays subsp. parviglumis and Zea mays subsp. mexicana. On the other hand, when Zea mays subsp. huehuetenanguensis DNA was probed on maize chromosomes, a lower affinity was detected, and the pattern of hybridization suggested intergenomical restructuring between the parental genomes of maize. When DNA from Zea luxurians was used as probe, homogeneous hybridization signals were observed through all maize chromosomes. Lower genomic affinity was observed when DNA from Zea diploperennis was probed on maize chromosomes, especially at knob regions. Maize chromosomes hybridized with Zea perennis DNA showed hybridization signals on four chromosome pairs: two chromosome pairs presented hybridization signal in only one chromosomal arm, whereas four chromosome pairs did not show any hybridization. These results are in agreement with previous GISH studies, which have identified the genomic source of the chromosomes involved in the meiotic configurations of Z. perennis × maize hybrids. These findings allow postulating that maize has a parental genome not shared with Z. perennis, and the existence of intergenomic restructuring between the parental genomes of maize. Moreover, the absence of hybridization signals in all maize knobs indicate that these heterochromatic regions were lost during the Z. perennis genome evolution.

Warmer and Wetter Soil Stimulates Assimilation More than Respiration in Rainfed Agricultural Ecosystem on the China Loess Plateau: The Role of Partial Plastic Film Mulching Tillage.

Effects of agricultural practices on ecosystem carbon storage have acquired widespread concern due to its alleviation of rising atmospheric CO2 concentrations. Recently, combining of furrow-ridge with plastic film mulching in spring maize ecosystem was widely applied to boost crop water productivity in the semiarid regions of China. However, there is still limited information about the potentials for increased ecosystem carbon storage of this tillage method. The objective of this study was to quantify and contrast net carbon dioxide exchange, biomass accumulation and carbon budgets of maize (Zea maize L.) fields under the traditional non-mulching with flat tillage (CK) and partial plastic film mulching with furrow-ridge tillage (MFR) on the China Loess Plateau. Half-hourly net ecosystem CO2 exchange (NEE) of both treatments were synchronously measured with two eddy covariance systems during the growing seasons of 2011 through 2013. At same time green leaf area index (GLAI) and biomass were also measured biweekly. Compared with CK, the warmer and wetter (+1.3°C and +4.3%) top soil at MFR accelerated the rates of biomass accumulation, promoted greater green leaf area and thus shortened the growing seasons by an average value of 10.4 days for three years. MFR stimulated assimilation more than respiration during whole growing season, resulting in a higher carbon sequestration in terms of NEE of -79 gC/m2 than CK. However, after considering carbon in harvested grain (or aboveground biomass), there is a slight higher carbon sink (or a stronger carbon source) in MFR due to its greater difference of aboveground biomass than that of grain between both treatments. These results demonstrate that partial plastic film mulched furrow-ridge tillage with aboveground biomass exclusive of grain returned to the soil is an effective way to enhance simultaneously carbon sequestration and grain yield of maize in the semiarid regions.

Contrasting effects of biochar versus manure on soil microbial communities and enzyme activities in an Aridisol

Biochar can increase microbial activity, alter microbial community structure, and increase soil fertility in arid and semi-arid soils, but at relatively high rates that may be impractical for large-scale field studies. This contrasts with organic amendments such as manure, which can be abundant and inexpensive if locally available, and thus can be applied to fields at greater rates than biochar. In a field study comparing biochar and manure, a fast pyrolysis hardwood biochar (22.4Mgha−1), dairy manure (42Mgha−1 dry wt), a combination of biochar and manure at the aforementioned rates, or no amendment (control) was applied to an Aridisol (n=3) in fall 2008. Plots were annually cropped to corn (Zea maize L.). Surface soils (0–30cm) were sampled directly under corn plants in late June 2009 and early August 2012, and assayed for microbial community fatty acid methyl ester (FAME) profiles and six extracellular enzyme activities involved in soil C, N, and P cycling. Arbuscular mycorrhizal (AM) fungal colonization was assayed in corn roots in 2012. Biochar had no effect on microbial biomass, community structure, extracellular enzyme activities, or AM fungi root colonization of corn. In the short-term, manure amendment increased microbial biomass, altered microbial community structure, and significantly reduced the relative concentration of the AM fungal biomass in soil. Manure also reduced the percent root colonization of corn by AM fungi in the longer-term. Thus, biochar and manure had contrasting short-term effects on soil microbial communities, perhaps because of the relatively low application rate of biochar.

Single and double crop systems in the Argentine Pampas: Environmental determinants of annual grain yield

New avenues are being explored to increase food production in the extensive agriculture of highly productive temperate regions. Intensifying the use of land by sequencing two crops in a season (double cropping) may enhance annual land productivity in relation to single annual crops. Single soybean (Glycine max L. Merr.) and maize (Zea maize L.) are widespread in the Argentine Pampas while wheat (Triticum aestivum L.)–soybean double crop system is the most common land-intensive cropping system. The possibility for expanding the double cropping system is large although it has received insufficient attention. The objectives of the present study were to (i) describe the association between major environmental variables and grain yield of wheat–soybean double crop, maize and soybean single crops and (ii) compare their annual grain yield over a wide range of environments as a basis to evaluate the possible contribution to productivity expected from wheat–soybean double crop compared with maize and soybean single crops. Yield data from farms widely distributed across the Argentine Pampas and meteorological information from 30 stations distributed in the region were recorded and analyzed. A five-year period of on-farm yields were obtained from 132 groups of farmers nested in 11 zones. Variables analyzed were crop grain yields, glucose equivalents grain yields, rainfall, temperature, radiation, and frost-free period. The ratio between radiation and temperature (photo-thermal quotient; PTQ) was also considered as a grain yield determinant for wheat. Mean daily temperature during crop reproductive stages was an important determinant of maximum yields for all crops as described by a boundary-function fit. The highest grain yields of maize and soybean were obtained at moderate summer temperatures (21.8–23.5°C and 21.8–23.8°C, respectively). Wheat maximum yields increased with low spring temperatures (<18.3°C), following high photo-thermal quotients during reproductive stages. In contrast, the highest yields of double crop soybean were obtained at high summer temperatures (>21.2°C), which were associated with extended frost free periods. High yields of the wheat–soybean double crop system were obtained with cool temperatures during spring combined with a relatively extended frost free period and substantial summer rainfall. On-farm yields below the boundary-function appeared associated to low rainfall scenarios, especially in double cropped soybean fields. The geographical patterns of yield for wheat–soybean double crop system tended to be similar to that of maize and soybean single crops. The most highly productive area for the three cropping systems evaluated was located in the center of the Argentine Pampas. However, wheat–soybean double crops were more productive than soybean at any site, but their yields were slightly lower than those of maize. In addition, the work helped to identify possible areas where wheat–soybean double crop system may give relative higher advantages; particularly, in some of the currently least productive areas. Since nowadays, almost 60% of the studied area is sown with single soybean, the results suggest that there is an effective possibility to have a substantial increase in on-farm productivity, while still producing soybean, simply by expanding the double crop system.

Immobilization of soil copper using organic and inorganic amendments

AbstractThis experiment aimed to immobilize Cu in polluted agricultural soils via the application of agrochemicals to reduce its bioavailability to plants. A greenhouse pot experiment was established using a Cu contaminated vineyard topsoil collected from a farm in Greece. The soil was mixed with inorganic [i.e., zeolite (Z), Al‐oxide (AX), Mn‐oxide (MX), and phosphate rock (PR)] as well as organic amendments [i.e., activated charcoal (AC), commercial peat soil material (CP), and compost from olive oil processing wastes (COW)] with an application rate of 2.5% and cultivated by corn (Zea maize). After plant harvesting, Cu was measured separately in the aboveground biomass and roots, respectively, whereas the soil samples were analyzed for DTPA‐extractable and geochemical fractions of Cu (soluble + exchangeable fraction, sorbed and carbonate fraction, Fe‐/Mn‐oxides fraction, and organic fraction). The immobilizing agents, except MX, reduced the soluble plus exchangeable Cu in the treated soil. The lowest concentrations of the soluble plus exchangeable Cu occurred in the soil amended with AC followed by CP, AX, COW, PR, and Z, respectively. The amendments decreased the uptake of Cu by corn. Concentrations of Cu were between 11 and 38% lower in the above ground biomass and 19 and 48% lower in the roots than the control. The organic amendments were more effective than the inorganic additives. The AC was the most effective organic additive and AX was the most effective inorganic amendment.

Tissues Accumulation of Heavy Metals by Maize (Zea maize L.) Cultivated on Soil Collected from Selected Dumpsites in Ekiti State, Nigeria

Aims: The study examined the levels of heavy metals in tissues of maize (Zea mays L.), cultivated on four selected dumpsites in Ekiti State, Nigeria; with a view to discouraging constant cultivation of abandoned dumpsites. Study Design: It is an analytical study. Place and Duration of Study: The study was carried out in 2012 on selected dumpsites located in Ekiti State, Nigeria. Methodology: Representative soil samples collected from four dumpsites located in Ekiti State were analyzed for pH, organic matter and heavy metals, prior to plant cultivation. After maturity, heavy metals concentrations were determined in various sections of plant, using flame absorption spectrophotometer. All determinations were carried out in triplicates using standard analytical procedures. The results obtained were subjected to statistical analyses. Results: The results showed that these dumpsites were grossly polluted with heavy metals when Original Research Article Awokunmi et al.; ACSj, 5(2): 156-162, 2015; Article no.ACSj.2015.015 157 compared with control sites in the range: Cd (21.9-138.0), Co (11.1-60.8), Cr (9.0-29.8), Cu (7.018.0), Fe (125.0-752.0), Pb (35.0-60.0), Mn (11.0-47.1), Ni (15.0-29.8), Sn (3.5-9.6) and Zn (63.080.2), all in mg/kg. Moderate values of soil pH and organic matter content revealed that maize could thrive well on mentioned dumpsites. However, the plant accumulated elevated concentrations of heavy metals in their shoot, when compared with the root, with Cr and Pb having higher concentration range of 101-104 mg/kg and 109.9-158.2 mg/kg respectively in its shoot at all dumpsites investigated. Conclusion: Therefore, cultivation of arable crops on dumpsites should be discouraged as constant environmental monitoring is imperative.

Heavy Metals in Some Fruits and Cereals in Minna Markets, Nigeria

Food production and safety can be used as a measure of a nation’s economic growth and stability as well as the responsiveness of government to the need of its people. In Nigeria, fruits and cereals are grown and distributed to all parts of the country through retails. They are a source of energy and minerals to humans in particular. Trace elements do not provide calorie but play an important role in the metabolic regulations of the human body systems if present in required amounts. They are co-enzymes and co-factors in human system which play different roles in growth, metabolism and immune system development. They can however bio-accumulate over a period of time in vital human organs-lungs, kidney, heart, liver and the brain causing serious damages and death. Worldwide food quality is monitored through metal analysis. This study was carried out in Minna, Nigeria, located 9°36’ 50N; 6°33’25E with nearly 300,000 inhabitants. The trace metals Fe, Pb, Cr, Mn, Cu and Zn were analysed from Rice (Oryza sativa), Maize (Zea maize), Guinea corn (Sorghum bicolor) and Millet (Panicum miliaceum) and edible parts of Banana (Musa spp), Orange (Citrus auratium), Pineapple (Ananas comossus), Watermelon (Citrullus lanatus) and Apple (Malus domestica). Fe was 18.400-252.160 and 1.120-20.800 mg/kg in fruits. In cereals, Cr was not detectable while Pb (1.154 mg/kg) was found only in maize. Fe content was considerably low in cereals compare to fruits. Compare to research elsewhere, similarities and dis-similarities in metals concentration were observed.

In vivo and in vitro inhibition of Spodoptera littoralis gut-serine protease by protease inhibitors isolated from maize and sorghum seeds

Seeds of cereals (Gramineae) are a rich source of serine proteinase inhibitors of most of the several inhibitor families. In the present study, trypsin and chymotrypsin inhibitory activities was detected in the seed flour extracts of three varieties of maize (Zea maize) and six varieties of sorghum (Sorghum bicolor). The maize variety, Hi Teck 2031 and the sorghum variety, Giza 10 were found to have higher trypsin and chymotrypsin inhibitory potentials compared to other tested varieties for which they have been selected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Maize and sorghum purified proteins showed a single band on SDS-PAGE corresponding to molecular mass of 20.0 and 15.2 kDa for maize and sorghum PIs respectively. The purified inhibitors were stable at temperature below 60 °C and were active at wide range of pH from 2 to 12 pH. The kinetic analysis revealed non-competitive type of inhibition for both inhibitors against both enzymes. The inhibitor constant (Ki) values suggested high affinity between inhibitors and enzymes. Purified inhibitors were found to have deep and negative effects on the mean larval weight, larval mortality, pupation and mean pupal weight of S.littoralis where maize PI was more effective than sorghum PI. It may be concluded that maize and sorghum protease inhibitor gene(s) could be potential targets for future studies in developing insect resistant transgenic plants.

Impact of land-use change towards perennial energy crops on earthworm population

The aim of the study was to investigate the impact of the cultivation of newly introduced perennial bioenergy crops on earthworm species composition, number and biomass at an experimental site in Western Germany. The included crops were Szarvazi (Agropyron elongatum), Switchgras (Panicum virgatum), Sida (Sida hermaphrodita), Silphie (Silphium perfolatum), Igniscum (Fallopia sachalinensis), and a wild flower mix (WFM) relative to silage (Zea maize). In sum, earthworm population at that site consisted of 8 species, Lumbricus rubellus and Allolobophora cupulifera being dominant species. Species number varied in a range of WPM (8)>Szarvazi (7)>Sida (6)>Silphie, Igniscum (5)>Switchgras, Maize (4). Earthworm number and biomass significantly increased in all newly introduced energy crops. On comparison within the perennial crops, it was found that earthworm number was significantly highest in Sida and lowest in Switchgras plots. The differences within the remaining crops were small and not significant. From an agro-ecological point of view and deduction from earthworm population data, it might be concluded that Szarvasi, Sida and wild flower mix can be seen as important energy crops in future bioenergy production in Western Germany.

REMOTE SENSING FOR DETECTING AND DISTINGUISHING MOISTURE AND NITROGEN STRESS IN MAIZE

Remote sensing has been known as a robust technique in precision farming over the last quarter of the 20th century. It has been successfully used to asses many biophysical and biochemical properties of various crops. Detecting stress in crops at an early growth stage is important to limit crop reductions and therefore increasing productivity. Thus, remote sensing may be a valuable tool for precision farming in cereal production. The present study was conducted to investigate the effectiveness of broad band and hyperspectral remotely sensed data to quantify maize (Zea maize L.) grain yield under moisture and nitrogen deficiency stresses. The results demonstrated strong significant correlations between various crop properties and some vegetation indices. RVI, SAVI, OSAVI and R750/R550 were found to be sensitive to maize grain yield (r > 0.80). The correlations with grain yield were found to be strongest at the grain filling stage. Penalized Linear Discrimnant Analysis (PLDA) and Principle Component Analysis (PCA) demonstrated the possibility to distinguish between moisture and nitrogen deficiency stress.