Zea mays

Inoculation of maize silage with Lactobacillus buchneri (5 x 10(5) c.f.u. g(-1) of maize silage) prior to ensiling results in the formation of aerobically stable silage. After 9 months, lactic acid bacterium counts are approximately 10(10) c.f.u. g(-1) in these treated silages. An important subpopulation (5.9 x 10(7) c.f.u. g(-1)) is able to degrade 1,2-propanediol, a fermentation product of L. buchneri, under anoxic conditions to 1-propanol and propionic acid. From this group of 1,2-propanediol-fermenting, facultatively anaerobic, heterofermentative lactobacilli, two rod-shaped isolates were purified and characterized. Comparative 16S rDNA sequence analysis revealed that the newly isolated bacteria have identical 16S rDNA sequences and belong phylogenetically to the L. buchneri group. DNA-DNA hybridizations, whole-cell protein fingerprinting and examination of phenotypic properties indicated that these two isolates represent a novel species, for which the name Lactobacillus diolivo...

Cellulose nanofibers with a size range of 5–100 nm have the potential to be a low cost renewable material that has application in a range of products. However, current chemical methods to produce crystalline nanofibers suffer from low yields and high chemical costs, while mechanical methods require high energy costs. Methods to lower the energy costs of the mechanical methods have not been well documented in the literature. A bleached softwood kraft pulp was processed using a mechanical dispersion mill and a homogenizer to produce cellulose nanofibers. Two different commercial enzymes were used to pretreat the wood fibers before the mechanical treatments. The resulting nanofibers were characterized by light microscopy, atomic force microscopy, and inverse gas chromatography. Results indicate that the dispersion mill does not affect the overall pulp fiber fibrillation, but does help prepare the sample for the homogenizer. Most fibrillation occurs after three passes through the homogenizer. The enzyme pretreatment has little effect on the size of the fibers, but does allow for higher solids to pass through the homogenizer without clogging. The dispersion component of surface energy of the resulting nanofibrils is impacted by the type of enzyme used. The measurement of acid–base properties proved to be challenging using current IGC experimental protocols.

Twenty seven mixed-breed growing rabbits (1.2-1.3 kg body weight) aged 10-12 weeks were used to study the effects of the dietary replacement of maize with sun-dried cocoa pod husks on the performance of growing rabbits in a 6-week trial. Three treatment diets were compounded whereby sun-dried cocoa pod husks replaced maize at 0, 50, and 100 %, respectively. The animals were divided among the three treatment diets so that each diet had 3 replicates of 3 animals each. Feed intake and weight gain were recorded; faeces were also collected for digestibility trials, and cost analysis was also carried out. Results showed a significant difference (P < 0.05) in daily feed intake between the dietary treatments. However, there was no significant difference (P > 0.05) in the final metabolic weights, total metabolic weight gain, daily growth rate, and feed conversion ratio between the treatments. The digestibility study showed a decrease in the digestibility of dry matter and metabolisable...

Maize is a major crop and a model plant for studying C4 photosynthesis and leaf development. However, a genomewide regulatory network of leaf development is not yet available. This knowledge is useful for developing C3 crops to perform C4 photosynthesis for enhanced yields. Here, using 22 transcriptomes of developing maize leaves from dry seeds to 192 h post imbibition, we studied gene up- and down-regulation and functional transition during leaf development and inferred sets of strongly coexpressed genes. More significantly, we developed a method to predict transcription factor binding sites (TFBSs) and their cognate transcription factors (TFs) using genomic sequence and transcriptomic data. The method requires not only evolutionary conservation of candidate TFBSs and sets of strongly coexpressed genes but also that the genes in a gene set share the same Gene Ontology term so that they are involved in the same biological function. In addition, we developed another method to predict...

Increasing evidences have indicated that humic substances can induce plant growth and productivity by functioning as an environmental source of auxinic activity. Here we comparatively evaluate the effects of indole-3-acetic acid (IAA) and humic acids (HA) isolated from two different soils (Inseptsol and Ultisol) and two different organic residues (vermicompost and sewage sludge) on root development and on activities of plasmalemma and tonoplast H+ pumps from maize roots. The data show that HA isolated from these different sources as well as low IAA concentrations (10−10 and 10−15 M) improve root growth through a markedly proliferation of lateral roots along with a differential activation not only of the plasmalemma but also of vacuolar H+-ATPases and H+-pyrophosphatase. Further, the vacuolar H+-ATPase had a peak of stimulation in a range from 10−8 to 10−10 M IAA, whereas the H+-pyrophosphatase was sensitive to a much broader range of IAA concentrations from 10−3 to 10−15 M. It is proposed a complementary view of the acid growth mechanism in which a concerted activation of the plasmalemma and tonoplast H+ pumps plays a key role in the root cell expansion process driven by environment-derived molecules endowed with auxinic activity, such as that of humic substances.

In the stage of in vitro of this research which was arranged in vitro and in vivo media, the effect on callus induction and plant regeneration in 6 different varieties of 2,4-D doses (0, 2, 4, 6, 8 and 10 mg/l) through callus culture was investigated. In the stage of in vivo, samples from the root tips composed of the callus of all maize varieties were taken, and the changes observed in the chromosomal numbers in maize lines were evaluated. As a result of the microscopic analyses of the root tips obtained through the application of 2,4-D auxin in different corn varieties in different doses, changes were observed in the chromosomal numbers of Pioneer 31N27 (2n=18), Pioneer 3223 (2n=19) and Pioneer 34N24 (2n=19) maize varieties. Mitotic anomaly observed through the application of 2,4-D was established as aneuploidy (the change of the chromosomal number in genome) and it was found to form as the decrease of the chromosomal number (hipoploidy). According to the data found, the dose of 2,4-D to be used in the transgenic maize producing studies to be utilized in Turkey was determined to be 2 mg/l providing the highest callus formation ratio but causing no chromosomal deviations.

Insecticidal protein genes from the bacterium Bacillus thuringiensis (Bt) are expressed by transgenic (Bt) crops for effective and environmentally safe pest control. The development of resistance to these insecticidal proteins is considered the most serious threat to the sustainability of Bt crops. Resistance in fall armyworm (Spodoptera frugiperda) populations from Puerto Rico to transgenic corn producing the Cry1Fa insecticidal protein resulted, for the first time in the USA, in practical resistance and Bt corn was withdrawn from the local market. In this study, we used a field-collected Cry1Fa corn-resistant strain (456) of S. frugiperda to identify the mechanism responsible for field-evolved resistance. Binding assays detected reduced Cry1Fa, Cry1Ab, and Cry1Ac but not Cry1Ca toxin binding to midgut brush border membrane vesicles (BBMV) from larvae of 456 compared to a susceptible (Ben) strain. This binding phenotype is descriptive of Mode 1 type resistance to Bt toxins. Compari...

The effects of plantain starch obtained from the unripe fruit of the plantMusa paradisiaca L. (Musaceae) on the mechanical and disintegration properties of paracetamol tablets have been investigated in comparison with the effects of corn starch BP using a 23 factorial experimental design. The individual and combined effects of nature of starch binder (N), concentration of starch binder (C), and the relative density of tablet (RD) on the tensile strength (TS), brittle fracture index (BFI), and disintegration time (DT) of the tablets were investigated. The ranking of the individual effects on TS was RD>C≫N, on BFI was C≫RD>N and on DT was N>C>RD. The ranking for the interaction effects on TS and DT was N-C≫N-RD>C-RD, while that on BFI was N-C≫C-RD>N-RD. Changing nature of starch from a “low” (plantain starch) to a “high” (corn starch) level, increasing the concentration of starch binding agent from 2.5% to 10.0% wt/wt, and increasing relative density of the tablet from 0.80 to 0.90, led to increase in the values of TS and DT, but a decrease in BFI. Thus, tablets containing plantain starch had lower tensile strength and disintegration time values than those containing corn starch, but showed better ability to reduce the lamination and capping tendency in paracetamol tablet formulation. The interaction between N and C was significantly (P<.001) higher than those between N and RD and between C and RD. There is therefore the need to carefully choose the nature (N) and concentration (C) of starch used as binding agent in tablet formulations to obtain tablets of desired bond strength and disintegration properties. Furthermore, plantain starch could be useful as an alternative binding agent to cornstarch, especially where faster disintegration is required and the problems of lamination and capping are of particular concern.

Bu çalışmada humik asidin (50, 100, 200, 400 ve 600 ppm) mısır (Zea mays L. cv. 3167) bitkisinde tohum çimlenmesi ve erken fide evresindeki etkileri araştırılmıştır. 50 ve 100 ppm'lik humik asit uygulamaları mısır tohumlarının çimlenmesi üzerinde inhibitör etki yapmazken, 200 ve 400 ppm'lik humik asit çimlenmeyi % 2, 600 ppm'lik humik asit ise % 4 oranında inhibe etmiştir. Uygulanan humik asit konsantrasyonları mısır fidelerinde kök ve gövde büyümesi üzerinde istatistiksel olarak önemli bir değişime neden olmamıştır (P>0.05). Buna rağmen, mısır fidelerinin taze ve kuru ağırlıklarının sadece 200, 400 ve 600 ppm'lik humik asit uygulamaları sonucu kontrole göre önemli derecede arttığı belirlenmiştir (P<0.05). Yapraklardaki fotosentetik pigment miktarı humik asit uygulamaları sonucu önemli derecede azalırken, çözünür protein miktarı artmıştır. 400 ve 600 ppm'lik humik asit mısır yapraklarındaki süperoksid dismutaz (SOD) aktivitesinin önemli derecede azalmasına neden olmuştur. Bu sonuçlara göre potasyum humat etkileriyle bitki gelişimi arasında yakın bir etkileşim olduğu, özellikle de fotosentetik pigment ve protein metabolizmasının etkilendiği söylenebilir. Ancak bu değişimlerin potasyum humatın besleyici özelliğinden mi yoksa bitkilerdeki biyokimyasal ve moleküler yollar üzerindeki direkt etkisinden mi kaynaklandığını açıklamak için farklı çalışmalara ihtiyaç vardır.
ABSTRACT
In this study, the effect of potassium humate (50, 100, 200, 400 ve 600 mg L-1) on seed germination and seedling growth of maize (Zea mays L. cv. 3167) was investigated. Seed germination of maize was not affected by 50 ve 100 mg L-1

Solid-liquid equilibrium (SLE) for binary mixture of Propafenone Hydrocloride (PP) with Metoprolol Tartrate (MT) was investigated using differential scanning calorimetry (DSC) and corresponding activity coefficients were calculated. Simple eutectic behavior for this system was observed. The excess thermodynamic functions: G(E) and S(E) for the pre-, post-, and eutectic composition have been obtained using the computed activity coefficients data of the eutectic phase with their excess chemical potentials μi(E) (i=1, 2). The experimental solid-liquid phase temperatures were compared with predictions obtained from available eutectic equilibrium models. The results indicate non-ideality in this mixture. Also, the compatibility of each component and their eutectic mixture with usual excipients was investigated, and the DSC experiments indicate possible weak interactions with α-lactose monohydrate and compatibility with corn starch. The results obtained were confirmed by FT-IR measurements.

The importance of breakfast cereal flakes (BCF) in Western diets deserves an understanding of changes in their mechanical properties and microstructure that occur during soaking in a liquid (that is, milk or water) prior to consumption. The maximum rupture force (RF) of 2 types of breakfast flaked products (BFP)--corn flakes (CF) and quinoa flakes (QF)--were measured directly while immersed in milk with 2% of fat content (milk 2%) or distilled water for different periods of time between 5 and 300 s. Under similar soaking conditions, QF presented higher RF values than CF. Soaked flakes were freeze-dried and their cross section and surface examined by scanning electron microscopy. Three consecutive periods (fast, gradual, and slow reduction of RF) were associated with changes in the microstructure of flakes. These changes were more pronounced in distilled water than in milk 2%, probably because the fat and other solids in milk become deposited on the flakes&#39; surface hindering liqu...

We have mapped the quantitative trait loci (QTLs) conferring resistance to sorghum downy mildew (Peronosclerospora sorghi; SDM) and Rajasthan downy mildew (P. heteropogoni; RDM), two species of DM prevalent throughout India. QTL mapping was carried out on a backcross population of 151 individuals derived from a cross between CM139 (susceptible parent) and NAI116 (highly resistant to both SDM and RDM). Heritability estimates were 0.74 for SDM and 0.67 for RDM. Composite interval mapping combined with a linkage map constructed with 80 simple sequence repeat (SSR) markers resulted in the identification of three QTLs (one each on chromosomes 2, 3 and 6) for SDM resistance and two QTLs (one each on chromosomes 3 and 6) for RDM resistance, all of which were contributed by NAI116. The significance of the major QTL on chromosome 6 (bin 6.05) that confers resistance to diverse DMs in tropical Asia, including SDM and RDM in India, was also verified. The results confirmed that some common QTLs contribute to both SDM and RDM resistance, while additional loci might specifically govern resistance to SDM. The QTL information generated in this study provide information that will aid in undertaking an integrated breeding strategy for the transfer of resistance to SDM and RDM in maize lines using marker-assisted selection.

Pathogenesis-related (PR) proteins are plant proteins that are induced in response to pathogen attack. PR proteins are grouped into independent families based on their sequences and properties. The PR-4 family comprises class I and class II chitinases. We have isolated a full-length cDNA encoding a chitinase from maize which shares a high degree of nucleotide and amino acid sequence homology with the class II chitinases of the PR-4 family of PR proteins. Our results indicate that fungal infection, and treatment either with fungal elicitors or with moniliformin, a mycotoxin produced by the fungus Fusarium moniliforme, increase the level of ZmPR4 mRNA. In situ mRNA hybridization analysis in sections obtained from fungus-infected germinating embryos revealed that ZmPR4 mRNA accumulation occurs in those cell types that first establish contact with the pathogen. ZmPR4 mRNA accumulation is also stimulated by treatment with silver nitrate whereas the application of the hormones gibberellic acid or acetylsalicylic acid has no effect. Wounding, or treatment with abscisic acid or methyl jasmonate, results in accumulation of ZmPR4 mRNA in maize leaves. Furthermore, the ZmPR4 protein was expressed in Escherichia coli, purified and used to obtain polyclonal antibodies that specifically recognized ZmPR4 in protein extracts from fungus-infected embryos. Accumulation of ZmPR4 mRNA in fungus-infected maize tissues was accompanied by a significant accumulation of the corresponding protein. The possible implications of these findings as part of the general defence response of maize plants against pathogens are discussed.