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Crop wild relatives (CWRs) have provided breeders with several 'game-changing' traits or genes that have boosted crop resilience and global agricultural production. Advances in breeding and genomics have accelerated the identification of valuable CWRs for use in crop improvement. The enhanced genetic diversity of breeding pools carrying optimum combinations of favorable alleles for targeted crop-growing regions is crucial to sustain genetic gain. In parallel, growing sequence information on wild genomes in combination with precise gene-editing tools provide a fast-track route to transform CWRs into ideal future crops. Data-informed germplasm collection and management strategies together with adequate policy support will be equally important to improve access to CWRs and their sustainable use to meet food and nutrition security targets.

This research paper presents a step by step conceptual design and life prediction approach for the design, modeling and simulation of head shaft of a belt bucket elevator, to be used for conveying grains to a height of 33.5 m and at the rate of 200 tons/h. output. For this elevator system, the force and torque acting on the head shaft as well as the bending moment were calculated. Furthermore, the diameter of each cross section of the shaft was determined taking into consideration the geometric and fatigue stress concentration factors, due to shoulders which contribute significantly to most fatigue failures of shafts. The stress induced on the shaft by the force and the factor of safety for each cross section of the shaft was calculated using the DE-Goodman criterion. The model of the shaft was created from the calculated diameters and subjected to static and fatigue analysis using SolidWorks FEA. The results were validated by comparing the values from the FEA and the calculated values for stress and factor of safety of the critical section of the shaft, which showed an equivalent value. The FEA gave a fatigue load factor greater than one, which signifies that the shaft will not go into failure mode within the infinite life cycle of the shaft. The value of the fatigue strength obtained from FEA was higher than the value for the maximum von misses stress of the shaft, this result shows that the head shaft will sustain the loading stresses over a finite life prediction. This research is significant because the stress induced forces on the head shaft from each component of the elevator system were properly identified and analyzed so as to obtain precise results for life prediction.

Pyrolysis is becoming a prominent method for producing bio-oil from biomass. It has the potential to contribute to the development of a viable renewable fuel market while also ensuring environmental sustainability. In this study, bio-oil was produced from abundantly available pig hair in a fixed bed reactor. The influence of pyrolysis factors such as temperature and heating rate on the production of bio-oil, bio-char, and syngas was examined. The prepared materials were pyrolyzed at 50 °C intervals in the temperature range of 300 to 550 °C. The results showed that the pyrolysis temperature has a moderate impact on product yields and bio-oil properties. The maximum bio-oil yield of 51.8 wt% was obtained at a pyrolysis temperature of 450 °C while the other product yields were 39.5 wt.% of bio-char and 43.0 wt.% of non-condensable gasses. The viscosity, density, elemental analysis, API density, pH, moisture and ash contents, and other physicochemical parameters of bio-oil were measured, and the gross calorific value (HHV) and net calorific value (LHV) were determined to be 20.66 MJ/kg and 19.31 MJ/kg, respectively. The bio-oil had a low water content and pH value, as a result, the content of oxygenated compounds has decreased, favouring the presence of non-oxygenated chemical compounds as revealed by Fourier-transform infrared spectroscopy (FTIR) and Gas-chromatography and mass spectrometry (GC–MS). The bio-oil contained compounds such as 2,6-octadienal,3,7-dimethyl (38.86%), citral (24.9%),.beta.-myrcene (5.47%), linoelaidic acid (5.41%), trans-13-octadecanoic acid (4.32%), hydrocarbon, ester, alcohol, ketones, alkanes, fatty acid, toluene, aromatic etc. were identified in the bio-oil which can be used in the manufacturing of chemicals, pharmaceutical and dyes industries, paint and perfume industries, and flammable gasses. As technology progresses, bio-oil will become a more feasible alternative to diesel. This study demonstrated that pig hair is a viable feedstock for a wide range of prospective fossil fuel substitutes and has a wide range of uses in the chemical, pharmaceutical, and dye sectors, as well as the biodiesel industry.

The durability of a machine structure is based on its mechanical performance through its entire service life. To avoid structural failures in machines, it is a standard design practice that machines be analyzed based on the types of loading (static and fatigue) associated with it in order to design safe and dependable machine structures. These types of analyses are performed with the purpose of estimating the behavior of the mechanical parts under specific operational conditions. The aim of this research is to investigate the effect of different loading to the maximum load on the redesigned shafts of an existing cassava peeling machine capable of peeling at least one (10) tons of cassava tubers with different weight, size or shape per day to ascertain the effects on the bending moment, shear force, deflection angle, shear stress and bending stress, and evaluate if there is need to reduce or increase the thickness of the shafts to a standard considered to be safe and economical. The three shafts of the cassava peeling machine have been carefully analyzed to check for their fatigue life under different loading conditions. From the analysis, with stress values of 48.640MPa, 49.1289MPa, 3.06089MPa and shaft diameter values of 34.6799mm, 34.7955mm, 13.7941mm evaluated from the reduced stress diagrams and ideal diameter diagrams for abrasive cylinder shaft, peeling cylinder shaft, and retainer shaft respectively, gave positive results because none of stress values were greater than reduced stresses (calculated stress value from Tresca’s theory) on the respective shafts. Therefore, a standard steel shaft of 35mm diameter is appropriate for manufacturing of the machine and also safe and economical.

Societal Impact Statement Biodiversity is essential to food security and nutrition locally and globally. By reviewing the global state of edible plants and highlighting key neglected and underutilized species (NUS), we attempt to unlock plant food resources and explore the role of fungi, which along with the wealth of traditional knowledge about their uses and practices, could help support sustainable agriculture while ensuring better protection of the environment and the continued delivery of its ecosystem services. This work will inform a wide range of user communities, including scientists, conservation and development organizations, policymakers, and the public of the importance of biodiversity beyond mainstream crops. Summary As the world's population is increasing, humanity is facing both shortages (hunger) and excesses (obesity) of calorie and nutrient intakes. Biodiversity is fundamental to addressing this double challenge, which involves a far better understanding of the global state of food resources. Current estimates suggest that there are at least 7,039 edible plant species, in a broad taxonomic sense, which includes 7,014 vascular plants. This is in striking contrast to the small handful of food crops that provide the majority of humanity's calorie and nutrient intake. Most of these 7,039 edible species have additional uses, the most common being medicines (70%), materials (59%), and environmental uses (40%). Species of major food crops display centers of diversity, as previously proposed, while the rest of edible plants follow latitudinal distribution patterns similarly to the total plant diversity, with higher species richness at lower latitudes. The International Union for Conservation of Nature Red List includes global conservation assessments for at least 30% of edible plants, with ca. 86% of them conserved ex situ. However, at least 11% of those species recorded are threatened. We highlight multipurpose NUS of plants from different regions of the world, which could be key for a more resilient, sustainable, biodiverse, and community participation‐driven new “green revolution.” Furthermore, we explore how fungi could diversify and increase the nutritional value of our diets. NUS, along with the wealth of traditional knowledge about their uses and practices, offer a largely untapped resource to support food security and sustainable agriculture. However, for these natural resources to be unlocked, enhanced collaboration among stakeholders is vital.

This study evaluated the nutritional, morphometric and biochemical profiles of six (6) formulated instant weaning foods in comparison with a commercial weaning food (Nutrend) as positive control and the vital growers mesh as negative control. The six instant weaning foods were formulated from selected staple foods and protein supplements. Diets (A-C) were formulated from rice-lentil based and diets (D-F) from sweet potato- soybean based at respective ratios of 70:10, 60:20 and 50:30, and blended with groundnut, crayfish and smoked fish in varying quantity to make up 100 g. These were compared with Nutrend (G) and vital growers mash (H) serving as positive and negative controls, respectively. From the study, saponin contents for all formulated diets were within safe limit at levels

The impact of climate change is causing challenges for the agricultural production and food systems. More nutritious and climate resilient crop varieties are required, but lack of available and accessible trait diversity is limiting crop improvement. Crop wild relatives (CWR) are the wild cousins of cultivated crops and a vast resource of genetic diversity for breeding new, higher yielding, climate change tolerant crop varieties, but they are under-conserved (particularly in situ), largely unavailable and therefore underutilized. Here we apply species distribution modelling, climate change projections and geographic analyses to 1261 CWR species from 167 major crop genepools to explore key geographical areas for CWR in situ conservation worldwide. We identify 150 sites where 65.7% of the CWR species identified can be conserved for future use., Holly Vincent et al. use species distribution modeling, climate change projections, and geographical analyses of more than 1200 crop wild relatives, identifying 150 key conservation areas most effective in preserving genetic diversity of crop wild relatives.

We assess the impact of corruption on firm growth using the World Bank Enterprise Survey (WBES) data on Nigerian firms for the periods 2006 and 2008. We measure corruption as firms’ informal payments to get things done faster and bypass due process. Firm growth is measured as sales growth of firms. To address endogeneity issues and the possibility of measurement error, we use industry averages of firms’ informal payments as an instrument in a Two-Stage Least Squares (2SLS) estimation. The results we obtain for both 2006 and 2008 confirm that informal payments substantially hinder firm growth in Nigeria. The results are robust and still hold after controlling for city variation and omitting outliers. The findings suggest that in the quest to improve firm growth, measures that focus on implementing frameworks that shorten the duration required for documentation and other firm-related services provided by the government would discourage informal payments and thus, improve firms’ sales growth.

In 2019, nearly 690 million people were hungry, indicating that the achievement of Zero Hunger by 2030 is not on-track. The enhanced conservation and use of crop diversity, which demonstrably improves farm productivity and hence food security and nutrition, could be one of the solutions to this problem. The broadening of the inter- and intra-specific diversity of crops contributes to dietary diversification and nutrition and improves the resilience of production systems to shocks, especially the biotic and abiotic stresses attributed to climate change. Examples of successful interventions that resulted in enhanced on-farm crop diversity are provided. Relevant tools and guidelines to strengthen national capacities for the enhanced on-farm management of plant genetic resources for food and agriculture are also highlighted. Guidance, based primarily on the Second Global Plan of Action for Plant Genetic Resources for Food and Agriculture, is presented to enable the conservation of farmers’ varieties/landraces, their genetic improvement and seed delivery systems; promote their cultivation, consumption and marketing; develop and implement policies; foster partnerships and strengthen requisite institutional and human capacities. Finally, the case is made for research and development, including using modern techniques, to achieve these aims.

Property concepts refer to properties, qualities or characteristics of referents (Thompson 1988). In many languages, there seems to be a correspondence between the expression of property concepts and the adjective category. There are however languages that express property concepts via means other than the adjective category. This paper examines the means by which property concepts are expressed in Etulo. It is observed that property concepts in Etulo are expressed by qualificatives. Etulo qualificatives subsume a small class of adjectives, a subset of verbs and nouns, and a class of ideophones. We adopt Dixon’s (2004) typological framework in establishing a distinct category of adjectives in Etulo.

This paper examines the negation typology of two Benue Congo languages, Igbo and Etulo. It discusses the similarities and differences evident in the negation marking strategies of both languages. From our findings, it is observed that despite the differences, Etulo and Igbo unanimously make a distinction between the standard negation marker and other types of negation markers such as the prohibitive negation marker as in Igbo and the interrogative negation marker as in Etulo. The distinction made in both languages lends support to the assumption in negation studies that the negative morpheme associated with standard negation often differs from the negative marker used in the negation of other construction types such as the prohibitive, and polar questions. This work adopts a descriptive approach in the analysis of the Igbo and Etulo language data. The Igbo language data presented and analyzed were obtained from the existing grammatical description of negation in Igbo while the Etulo language data were obtained from Etulo language consultants using the elicitation method.

Etulo is an Idomoid language spoken in two Nigerian states: Taraba and Benue. This work gives an overview of the core linguistic features of Etulo as spoken in Benue state. At the phonological level, we highlight the Etulo sound system, its tonal features, syllable structure and the most common phonological processes attested. At the morphological level, we focus on its derivational morphology which involves morphological processes such as affixation, reduplication and compounding. We give a list of the identified word classes with emphasis on the noun and verbal system. Also discussed, are grammatical features which are considered areal such as its rich class of ideophones and verb serialization. Our findings show that Etulo shares some core structural features with other Idomoid languages such as Idoma. The data used for this study are obtained from Etulo language consultants who are native speakers. We adopt a descriptive approach in the analysis of the Etulo language data.

The relationship between moral reasoning and leadership style has received considerable attention for decades, however this has been not fully explicated as different leadership styles elist different ethical values. What constitutes moral behaviour is conflicting and subjective. This study examines public leaders’ degree of moral judgment associated with leadership styles in a public sector organization. To test the hypothesized relationship, data were collected using questionnaire survey distributed to 550 workers out which 300 were found worthy to be used. The Defining Issues Test (DIT2) and the Multifactor leadership questionnaire (MLQ X5) were completed by leaders and subordinates respectively. The PLS path analysis of the structural model indicates significant statistical relationship between cognitive moral development (CMD) and transactional leadership style (TSL) ( β= -0.214, P< 0.012). However, we argue that cognitive moral development is amiable to the individual qualities of the leader that might necessitate the application of particular leadership style and behaviour. We also found collaboration evidence that leaders high in cognitive moral development are perceived more as transformational leaders by their subordinates. Finally, we suggest that the dichotomies between moral reasoning and leadership style are hinged more on individual leadership values and motivational beliefs.

Genetic variation is a source of phenotypic diversity and is a major driver of evolutionary diversification. Heritable variation was observed and used thousands of years ago in the domestication of plants and animals. The mechanisms that govern the inheritance of traits were later described by Mendel. In the early decades of the twentieth century, scientists showed that the relatively slow rate of natural mutation could be increased by several orders of magnitude by treating Drosophila and cereals with X-rays. What is striking about these achievements is that they came in advance of experimental evidence that DNA is the heritable material. This highlights one major advantage of induced mutations for crop breeding: prior knowledge of genes or gene function is not required to successfully create plants with improved traits and to release new varieties. Indeed, mutation induction has been an important tool for crop breeding since the release of the first mutant variety of tobacco in the 1930s. In addition to plant mutation breeding, induced mutations have been used extensively for functional genomics in model organisms and crops. Novel reverse-genetic strategies, such as Targeting Induced Local Lesions IN Genomes (TILLING), are being used for the production of stable genetic stocks of mutant plant populations such as Arabidopsis, barley, soybean, tomato and wheat. These can be kept for many years and screened repeatedly for different traits. Robust and efficient methods are required for the seamless integration of induced mutations in breeding and functional genomics studies. This chapter provides an overview of the principles and methodologies that underpin the set of protocols and guidelines for the use of induced mutations to improve crops.

In languages, different criteria are often adopted in the classification of the verb category many of which are language specific or universal. Etulo makes a distinction between simple and complex predicates. This work discusses serial verb construction (SVC) as a type of complex predicate using the typological criteria proposed in Aikhenvald (2006). Etulo SVCs have diverse semantic and grammatical functions. They express benefactive, instrumental, comparative meaning, as well as prepositional and adverbial notions indicating direction using motion verbs. Different types of serial verb constructions (SVCs) are established: the symmetric vs asymmetric type, contiguous vs non-contiguous, and the optional vs obligatory type. The SVC is further distinguished from a similar multi-verb construction known as the consecutive construction.

The options for increasing food production by at least 70% over the next four decades so as to keep pace with a rapidly increasing human population are bedeviled by erratic climatic conditions, depleted arable lands, dwindling water resources and by the significant environmental and health costs for increasing the use of agrochemicals. Enhanced productivities through “smart” crop varieties that yield more with fewer inputs is a viable option. However, the genetic similarities amongst crop varieties—which render entire cropping systems vulnerable to the same stresses—coupled with unvarying parental materials limit the possibilities for uncovering novel alleles of genes and, hence, assembling new gene combinations to break yield plateaux and enhance resilience. Induced mutation unmasks novel alleles that are harnessed to breed superior crop varieties. The historical antecedents, theoretical and practical considerations, and the successes of induced mutations in crop improvement are reviewed along with how induced mutagenesis underpins plant functional genomics. The roles of cell and molecular biology techniques in enhancing the efficiencies for the induction, detection and deployment of mutation events are also reviewed. Also, the integration of phenomics into induced mutagenesis and the use of pre-breeding for facilitating the incorporation of mutants into crop improvement are advocated.

This paper examines strategies for promoting parent/teacher partnerships in assessment of children with emotional and behavioral disorder in schools. Descriptive survey design was used. The study was carried out in Ezeagu Local Government Area, Enugu State. Three research questions were formulated for the study. Questionnaire instrument of 30 items was used to illicit information from secondary school teachers. Mean statistics was used to analyze the data. It was found out that teachers' competence in communication skills, their knowledge of students cultural and home backgrounds and school support programme promote parent/teacher partnerships in assessment of children with behavioral and emotional disorder.

To test if stabilizing Ampicillin trihydrate (AT) with Aluminium-Magnesium Silicate (AMS) can enhance its antibacterial activities, different concentrations of AT solution and of a formulation of AT in the AMS, were made and used for sensitivity test on Salmonella gallinarum cultures. Also, S. gallinarum-infected chicks were treated with; 10 mg/Kg (AT), 10 mg/Kg (AT in AMS), 7.5 mg/Kg (AT), 7.5 mg/Kg (AT in AMS). Mean diameter of inhibition zone, 28.39 ± 2.07 mm produced by AT did not vary significantly (P > 0.05) from 26.36 ± 2.05 mm produced by AT in AMS. However, mean Salmonella gallinarum culture forming units per ml of bile, 17.6 ± 11 × 105of the untreated chicks and 3.4 ± 0.81 × 105(80.58% reduction), 2.4 ± 0.67 × 105(85.70% reduction), 5.4 ± 1.93 × 105(69.20% reduction ) and 0.38 ± 0.13 × 105(97.80% reduction ) of the respective treated groups, showed AMS significantly (P S. gallinarum infection, in vivo.

Global food security could be imperilled by the combined pressures from the effects of continually evolving climatic conditions, demographics and other socio-economic factors, the demands of the livestock, bioenergy and fibre industries for food-based substrates, the static or decreasing availability of natural resources for agriculture and the impracticality of increased use of economically and environmentally costly agricultural inputs. The optimal harnessing of plant genetic resources for food and agriculture (PGRFA) in manners that translate their repertoire of hidden potentials into significantly enhanced crop productivities has been severally identified as crucial to achieving the required considerably significant increases in food production. The scope of the problems and the plausible means for addressing them compel the devising of novel and more efficient ways for deploying PGRFA in need-based crop improvement programmes. We posit a continuum approach to the management of PGRFA which links seamlessly the effective conservation and access to PGRFA through their use in developing superior and resilient crop varieties to the provision of their high-quality seeds and planting materials to the growers. To achieve the mainstreaming of this paradigm, we propose the institutionalization of overarching national PGRFA strategies that prescribe result-oriented action plans spanning above three components of the management of PGRFA for a country's priority crops. We also describe the strategy as a means for identifying and assigning responsibilities to critical stakeholders and providing for the governance of all aspects of PGRFA activities over specific time frames. Steps to developing and adopting a national PGRFA strategy are also suggested.

Cassava (Manihot esculenta) is a major food staple for nearly 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. Additional losses also occur from deterioration during the post-harvest storage of roots. To help cassava breeders overcome these obstacles, the scientific community has turned to modern genomics approaches to identify key genetic characteristics associated with resistance to these yield-limiting factors. One approach for developing a genomics program requires the development of ESTs (expressed sequence tags). To date, nearly 23,000 ESTs have been developed from various cassava tissues, and genotypes. Preliminary analysis indicates existing EST resources contain at least 6000-7000 unigenes. Data presented in this report indicate that the cassava ESTs will be a valuable resource for the study of genetic diversity, stress resistance, and growth and development, not only in cassava, but also other members of the Euphorbiaceae family.

To test effect of a synthetic Aluminium-Magnesium Silicate (AMS) on anthelmintic efficacy of piperazine citrate (PC), 35 mice were infected by dosing each, 0.15 ml Helignosomoides bakeri sample which contained 200 infective larvae, per os. Following comfirmation of establishment of infection by faecal floatation, they were assigned into seven groups of 5 each, and were treated with piperazine citrate, per os, at rates of 110 mg/kg (PC), 110 mg/kg (PC in AMS), 82.5 mg/kg (PC), 82.5 mg/kg (PC in AMS), 55 mg/kg (PC) and 55 mg/kg (PC in AMS) respectively. The seventh group served as untreated control. Mean Eggs Per Gramm of faeces (EPG) were 375 ± 32.27, 175 ± 14.43, 830 ± 1.04, 70 ± 12.25, 850 ± 293.06, 370 ± 58.54 and 2,200 ± 2.55 respectively. This showed EPG reduction rates of 83%, 92%, 62%, 97%, 61% and 83% among the respective treated groups.

Contour tones are typically predominant in tone languages operating a contour system in contrast with tone languages operating the register system. This paper examines the underlying and surface characterization of contour tones (rising and falling tones) at the lexical level in Igbo. Adopting the Autosegmental approach originally proposed by Goldsmith (1976), it reinforces the composite nature of both contours in Igbo. From the data, evidence is given that contour tones in Igbo are mere surface features which are motivated by some underlying rules that arise from the merging of tone at morpheme boundaries, historical loss of segments and the association of a floating tone. The two rules are identified are the deletion and docking rule. The manifestation of the latter is premised on the application of the former. The application of both rules is equally dependent on the fulfilment of some tone contour conditions such as presence of morpheme boundary, occurrence of contrasting tones at the morpheme boundary, similarity of vowels. The data used for this study are mostly individual words (place names and general nouns). These nouns are however morphologically derived complex words. The analysis shows that contour tones are usually induced at morpheme boundaries. Again, there is always a collapse of the contrasting tones realised on the tone bearing units (vowels) at the morpheme boundary. The morpheme boundary as used in this context and as applicable to Igbo is restricted to free morphemes. The first morpheme whose vowel is always affected by the deletion rule could start losing its original meaning overtime.

A significant number of studies reported linkages between ethical moral reasoning and transformational leadership (TFL) style, but questioned its moral foundation based on shared values and ethics. Thus, the issue of public leaders’ and subordinates’ degree of moral judgment and TFL behavior as perceived by followers is explored. The Defining Issues Test (DIT-2) and the Multifactor Leadership Questionnaire (MLQ X5) were completed by leaders and subordinates severely (Avolio & Bass, 2004; Rest, Narvaez, Bebeau, & Thoma, 1999). Path analysis of the structural model indicates positive significant statistical relationship between cognitive moral development (CMD) and TFL style (β = 0.120, t = 1.286, p < .10). Nevertheless, we indicate that the capacity to experience, discover, and anticipate ethical threats encourages the use of post-conventional stage in decision making, and this result adds to our understanding of the relationship between ethical reasoning and leadership style.

A 70% increase in food production is required over the next four decades to feed an ever-increasing population. The inherent difficulties in achieving this unprecedented increase are exacerbated by the yield-depressing consequences of climate change and variations and by the pressures on food supply by other competing demographic and socioeconomic demands. With the dwindling or stagnant agricultural land and water resources, the sought-after increases will therefore be attained mainly through the enhancement of crop productivity under eco-efficient crop production systems. ‘Smart’ crop varieties that yield more with fewer inputs will be pivotal to success. Plant breeding must be re-oriented in order to generate these ‘smart’ crop varieties. This paper highlights some of the scientific and technological tools that ought to be the staple of all breeding programs. We also make the case that plant breeding must be enabled by adequate policies, including those that spur innovation and investments. To arrest and reverse the worrisome trend of declining capacities for crop improvement, a new generation of plant breeders must also be trained. Equally important, winning partnerships, including public-private sector synergies, are needed for 21st century plant breeding to bear fruits. We also urge the adoption of the continuum approach to the management of plant genetic resources for food and agriculture as means to improved cohesion of the components of its value chain. Compellingly also, the National Agricultural Research and Extension System of developing countries require comprehensive overhauling and strengthening as crop improvement and other interventions require a sustained platform to be effective. The development of a suite of actionable policy interventions to be packaged for assisting countries in developing result-oriented breeding programs is also called for.

Solutions of different concentrations, of Ampicillin trihydrate (AT) and of a formulation of AT in Aluminium Magnesium Silicate (AMS), were used for sensitivity test on Salmonella gallinarum cultures. Also, S. gallinarum-infected chicks were treated with; 10 mg / Kg (AT), 10 mg / Kg (AT in AMS), 7.5 mg / Kg ( AT), 7.5 mg /Kg (AT in AMS). Mean inhibition area, 28.39 mm produced by AT did not vary significantly (P ) from 26.36 mm produced by AT in AMS. However, 17.5 105 Salmonella gallinarum culture forming units per ml of bile of the untreated chicks and 3.4 105 (80.58 % reduction), 2.5 105 (85.7 % reduction) , 5.4 105 (69.2 % reduction ) and 0.38 105 (97.8 % reduction ) of the respective treated groups, showed AMS significantly (P 0.01) improved AT`s ability to clear the infection, in vivo.

Solutions of different concentrations, of Ampicillin trihydrate (AT) and of a formulation of AT in Aluminium Magnesium Silicate (AMS), were used for sensitivity test on Salmonella gallinarum cultures. Also, S. gallinarum-infected chicks were treated with; 10 mg / Kg (AT), 10 mg / Kg (AT in AMS), 7.5 mg / Kg ( AT), 7.5 mg /Kg (AT in AMS). Mean inhibition area, 28.39 mm produced by AT did not vary significantly (P ) from 26.36 mm produced by AT in AMS. However, 17.5 105 Salmonella gallinarum culture forming units per ml of bile of the untreated chicks and 3.4 105 (80.58 % reduction), 2.5 105 (85.7 % reduction) , 5.4 105 (69.2 % reduction ) and 0.38 105 (97.8 % reduction ) of the respective treated groups, showed AMS significantly (P 0.01) improved AT`s ability to clear the infection, in vivo.

Mutation, the heritable change to the genetic make up of an individual, occurs naturally and has been the single most important factor in evolution as the changes that are passed on to offspring lead to the development of new individuals, species and genera. The first reported cases of artificial induction of mutations, that is, the creation of genomic lesions above the threshold observable in wild types, were in the 1920s with work on Drosophila, maize and barley. Since these pioneering activities, induced mutagenesis has become widespread in the biological sciences, primarily for broadening the genetic base of germplasm for plant breeding and, more recently, as a tool for functional genomics. Mutations are induced in plants by exposure of their propagules, such as seeds and meristematic cells, tissues and organs, to both physical and chemical agents with mutagenic properties [1]. In some instances, whole plants are also exposed. Physical mutagens are mostly electromagnetic radiation such as gamma rays, X-rays, UV light and particle radiation, including fast and thermal neutrons, beta and alpha particles. Chemical mutagens include alkylating agents (such as the commonly used ethyl methane sulfonate – EMS), intercalating agents (such as ethidium bromide)

A growing world population, changing climate and limiting fossil fuels will provide new pressures on human production of food, medicine, fuels and feed stock in the twenty-first century. Enhanced crop production promises to ameliorate these pressures. Crops can be bred for increased yields of calories, starch, nutrients, natural medicinal compounds, and other important products. Enhanced resistance to biotic and abiotic stresses can be introduced, toxins removed, and industrial qualities such as fibre strength and biofuel per mass can be increased. Induced and natural mutations provide a powerful method for the generation of heritable enhanced traits. While mainly exploited in forward, phenotype driven, approaches, the rapid accumulation of plant genomic sequence information and hypotheses regarding gene function allows the use of mutations in reverse genetic approaches to identify lesions in specific target genes. Such gene-driven approaches promise to speed up the process of creating novel phenotypes, and can enable the generation of phenotypes unobtainable by traditional forward methods. TILLING (Targeting Induced Local Lesions IN Genome) is a high-throughput and low cost reverse genetic method for the discovery of induced mutations. The method has been modified for the identification of natural nucleotide polymorphisms, a process called Ecotilling. The methods are general and have been applied to many species, including a variety of different crops. In this chapter the current status of the TILLING and Ecotilling methods and provide an overview of progress in applying these methods to different plant species, with a focus on work related to food production for developing nations.

Background The TILLING and Ecotilling techniques for the discovery of nucleotide polymorphisms were applied to three potato (Solanum tuberosum) cultivars treated with gamma irradiation. The three mutant cultivars tested were previously shown to exhibit salinity tolerance, an important trait in countries like Syria where increasing soil salinity is affecting agricultural production. Findings Three gene-specific primer pairs were designed from BAC sequence to amplify ~1 to 1.5 kb of gene target. One of the three primer pairs amplified a single gene target. We used this primer pair to optimize enzymatic mismatch cleavage and fluorescence DNA detection for polymorphism discovery. We identified 15 putative nucleotide polymorphisms per kilobase. Nine discovered polymorphisms were unique to one of the three tetraploid cultivars tested. Conclusion This work shows the utility of enzymatic mismatch cleavage for TILLING and Ecotilling in different varieties of potato. The method allows for rapid germplasm characterization without the cost and high informatics load of DNA sequencing. It is also suitable for mutation discovery in high-throughput reverse genetic screens.

Salt accumulation in soil surfaces, known as soil salinity, could lead to the impairment of plant growth and development and is manifested mostly under irrigated and dryland agriculture. Excess salts in the soil affects plants through osmotic stress; accumulation to toxic levels within the cells; and through the interference with the uptake of mineral nutrients. Rice productivity in several parts of the world is therefore severely limited by salinity on account of the prevalence of irrigation in rice farming. Tolerance to salt toxicity in plants is a genetic and physiologically complex trait. Halophytes (salt tolerant plants) are different from the salt-sensitive glycophytes in terms of peculiarities in their anatomy, ability to sequester otherwise toxic ions, and other physiologic processes. It is logical therefore to infer complexity also at the genetic level on account of the several pathways involved in these mechanisms. These complexities have confounded genetic improvement strategies for salinity tolerance in plants resulting in a paucity of saline tolerant plants, with only about 30 officially released saline tolerant crop varieties world-wide. Only one saline tolerant rice variety, Bicol, has been officially released to farmers. We review strategies being currently employed in the development of saline tolerant rice varieties. These include conventional plant breeding which is hampered by the lack of suitable genetic variation for this trait; the modest progress made through doubled haploidy; and the reliance on somaclonal variation, an unsustainably unpredictable strategy. This review also posits that while genetic transformation has led to the modification of certain physiological indices implicated in salinity tolerance in rice, in isolation, these modifications have not been translated to improved yield under salt stress. A more recently adopted strategy, induced mutagenesis, has led to some promising results. We argue that the production of induced rice mutants holds the greatest promise of these strategies for mitigating the scourge of soil salinity considering the relative ease with which other traits in this crop have been modified using this methodology. The underlying principles of induced mutagenesis; the modes of action of different mutagenic agents; and procedures for the rapid production and detection of mutants are also summarised. In order to enhance efficiency in the production, detection and incorporation of induced mutants into crop improvement programmes, we suggest the coupling of in vitro (such as doubled haploidy and cell suspension cultures) and molecular genetic techniques to this methodology. It is posited also that the efficiency of this process can be greatly enhanced by marker-aided selection while high throughput reverse genetics strategies could lead to the rapid detection of mutation events in target genes. It is concluded that with the plethora of genomics resources available for rice, the use of induced mutations for improving salinity tolerance (and other traits) would rely significantly on the concerted application of efficiency enhancing in vitro techniques and functional genomics strategies (including reverse genetics)

The collection of the available range of genetic variation in a gene pool, usually made of the cultivated species and their undomesticated relatives, is referred to as a germplasm collection. Increasingly, discriminator data generated using molecular genetic markers are either complementing or completely replacing those from morphological characters (known as descriptors) in surveys of genetic diversity. In addition to highlighting the state of knowledge on the specific applications of amplified fragment length polymorphisms (AFLPs) in surveys of plant genetic diversity, an attempt at a brief description and comparison of the different marker systems in use has also been made in this chapter. We have also attempted a description of the AFLP marker technology, its strengths and weaknesses, methodologies for generating reliable AFLP data, available resources (hardware, software, consumables); the kinds of questions for which AFLP data provide valid answers; and data management options. This chapter also highlights salient considerations that would guide decisions on the adoption of molecular marker assays.

The collection of the available range of genetic variation in a gene pool, usually made of the cultivated species and their undomesticated relatives, is referred to as a germplasm collection. Increasingly, discriminator data generated using molecular genetic markers are either complementing or completely replacing those from morphological characters (known as descriptors) in surveys of genetic diversity. In addition to highlighting the state of knowledge on the specific applications of amplified fragment length polymorphisms (AFLPs) in surveys of plant genetic diversity, an attempt at a brief description and comparison of the different marker systems in use has also been made in this chapter. We have also attempted a description of the AFLP marker technology, its strengths and weaknesses, methodologies for generating reliable AFLP data, available resources (hardware, software, consumables); the kinds of questions for which AFLP data provide valid answers; and data management options. This chapter also highlights salient considerations that would guide decisions on the adoption of molecular marker assays.

Musa (banana and plantain) is an important genus for the global export market and in local markets where it provides staple food for approximately 400 million people. Hybridization and polyploidization of several (sub)species, combined with vegetative propagation and human selection have produced a complex genetic history. We describe the application of the Ecotilling method for the discovery and characterization of nucleotide polymorphisms in diploid and polyploid accessions of Musa. We discovered over 800 novel alleles in 80 accessions. Sequencing and band evaluation shows Ecotilling to be a robust and accurate platform for the discovery of polymorphisms in homologous and homeologous gene targets. In the process of validating the method, we identified two single nucleotide polymorphisms that may be deleterious for the function of a gene putatively important for phototropism. Evaluation of heterozygous polymorphism and haplotype blocks revealed a high level of nucleotide diversity in Musa accessions. We further applied a strategy for the simultaneous discovery of heterozygous and homozygous polymorphisms in diploid accessions to rapidly evaluate nucleotide diversity in accessions of the same genome type. This strategy can be used to develop hypotheses for inheritance patterns of nucleotide polymorphisms within and between genome types. We conclude that Ecotilling is suitable for diversity studies in Musa, that it can be considered for functional genomics studies and as tool in selecting germplasm for traditional and mutation breeding approaches. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1395-5) contains supplementary material, which is available to authorized users.