Levels Of Nutrient Availability Research Articles

Effects of food restriction on growth, energy allocation, and sexual size dimorphism in Yarrow’s Spiny Lizard, Sceloporus jarrovii

Evolutionary biologists often view sexual size dimorphism (SSD) as a fixed genetic consequence of sexually antagonistic selection, but the actual magnitude of SSD may often be strongly dependent upon proximate environmental factors. Sexual differences in growth rate lead to male-biased SSD in wild populations of Yarrow’s Spiny Lizard ( Sceloporus jarrovii Cope, 1875), yet both sexes grow at similar rates under controlled laboratory conditions. We hypothesized that male-biased SSD in S. jarrovii reflects an obligatory sexual difference in energy allocation to growth versus competing functions, but that an ad libitum diet provides an energy surplus which overwhelms this sex-specific energetic trade-off. To test this hypothesis, we reared juveniles under high (3 crickets/d) and low (1 cricket/d) food availabilities. Food restriction dramatically reduced growth in both sexes but did not differentially affect growth of females relative to males. Food consumption did not differ between sexes, but males grew slightly faster than females at both levels of food availability, indicating a greater fractional allocation of available energy to growth. By contrast, females had larger fat bodies than did males, particularly under food restriction. This sexual difference in energy allocation to storage could explain the slightly higher growth rate of males relative to females.

Selection of preadapted populations allowed Senecio inaequidens to invade Central Europe

ABSTRACTInvasive species often evolve rapidly in response to the novel biotic and abiotic conditions in their introduced range. Such adaptive evolutionary changes might play an important role in the success of some invasive species. Here, we investigated whether introduced European populations of the South African ragwort Senecio inaequidens (Asteraceae) have genetically diverged from native populations. We carried out a greenhouse experiment where 12 South African and 11 European populations were for several months grown at two levels of nutrient availability, as well as in the presence or absence of a generalist insect herbivore. We found that, in contrast to a current hypothesis, plants from introduced populations had a significantly lower reproductive output, but higher allocation to root biomass, and they were more tolerant to insect herbivory. Moreover, introduced populations were less genetically variable, but displayed greater plasticity in response to fertilization. Finally, introduced populations were phenotypically most similar to a subset of native populations from mountainous regions in southern Africa. Taking into account the species’ likely history of introduction, our data support the idea that the invasion success of Senecio inaequidens in Central Europe is based on selective introduction of specific preadapted and plastic genotypes rather than on adaptive evolution in the introduced range.

Do nutrients and invertebrate herbivory interact in an artificial plant community?

Abstract The addition of nutrients has been shown to decrease the species richness of plant communities. Herbivores feed on dominant plant species and should release subdominant species from competitive exclusion at high levels of nutrient availability with a severe competitive regime. Therefore, the effects of nutrients and invertebrate herbivory on the structure and diversity of plant communities should interact. To test this hypothesis, we used artificial plant communities in microcosms with different levels of productivity (applying fertilizer) and herbivory (adding different numbers of the snail, Cepaea hortensis , and the grasshopper, Chorthippus parallelus ). For analyses, we assigned species to three functional groups: grasses, legumes and (non-leguminous) herbs. With the addition of nutrients aboveground biomass increased and species richness of plants decreased. Along the nutrient gradient, species composition shifted from a legume-dominated community to a community dominated by fast-growing annuals. But only legumes showed a consistent negative response to nutrients, while species of grasses and herbs showed idiosyncratic patterns. Herbivory had only minor effects, and bottom–up control was more important than top–down control. With increasing herbivory the biomass of the dominant plant species decreased and evenness increased. We found no interaction between nutrient availability and invertebrate herbivory. Again, species within functional groups showed no consistent responses to herbivory. Overall, the use of the functional groups grasses, legumes and non-leguminous herbs was of limited value to interpret the effects of nutrients and herbivory during our experiments.

Food intake, growth, and reproduction as affected by day length and food availability in the pond snail Lymnaea stagnalis*

With the aim of integrating the physiology and evolutionary ecology of Lymnaea stagnalis (Linnaeus, 1758), we studied the effects of day length and food availability on the energy budget. Snails were assigned to two different photoperiods and three levels of food availability. The snails were kept individually, and food consumption, growth, and egg production were measured for about 2 months. Snails could nearly compensate for a one-day starvation period by increasing the rate of food-intake. However, food-intake rates did not increase further after a starvation period of 2 days. Growth was well described by the Von Bertalanffy growth equation. The ultimate size of snails kept under medium-day conditions (MD; light:dark = 12:12 h) was not affected by food availability. By contrast, the ultimate size of snails kept under long-day conditions (LD; light:dark = 16:8 h) depended on food availability; those fed the lowest quantities grow the least. Dry-weight densities (dry weight/wet weight) of MD snails were considerably above those of LD snails. In MD snails, food availability did not appreciably affect dry-weight density. By contrast, in LD snails, dry-weight density decreased with decreasing food availability. The reproductive output of LD snails declined with declining food availability, but was 2 to 4 times that of MD snails. The difference in reproductive output was largely accounted for by the difference in stored energy, i.e. dry-weight density. To gauge the extent to which the conclusions from our laboratory work applied to free-living snails, a field study was conducted. The wild-caught snails' dry-weight density was also lowest in long-day conditions when most eggs were laid. However, the dry-weight densities during medium and short days were lower than the dry-weight densities of laboratory animals under LD conditions. Thus, in the field, snails stored less energy than in the laboratory.

Variation in tolerance to herbivory is mediated by differences in biomass allocation in aspen

1 Herbivore damage can select for tolerance in plant populations where genetic variation for tolerance exists. The causes underlying variation in tolerance are not fully resolved. We assessed the importance of two potential mechanisms for tolerance by examining its relationship with leaf photosynthetic rate and relative biomass allocation across plant organs. 2 We monitored responses of 12 aspen (Populus tremuloides) genotypes, grown in a common garden under two levels of nutrient availability, to defoliation in two successive seasons. Tolerance of each genotype was calculated as the difference in growth between defoliated and undefoliated trees grown under the same nutrient conditions. 3 Although light-saturated leaf photosynthesis increased in response to nutrient addition and defoliation, it did not vary among genotypes and was not correlated with tolerance. 4 Tolerance was, however, correlated with patterns of biomass allocation. Under low-nutrient conditions it was positively correlated with the proportion of biomass in stems just prior to defoliation, while under high-nutrient conditions it was correlated with greater allocation to stems in response to damage. 5 Herbivores may select for specific patterns of biomass allocation in trees, and do so differently in different environments. The positive correlation between tolerance and relative allocation to stems, as opposed to roots, runs counter to reports from studies of herbaceous species and underscores the need for further exploration of mechanisms of tolerance in woody plants.

Multiple stressor effects of herbicide, pH, and food on wetland zooplankton and a larval amphibian

Interactions of herbicides and natural environmental stressors such as pH and food availability are poorly understood. We tested a chemical formulation of triclopyr (Release ®) at environmentally relevant test concentrations (0.25 and 0.50 mg L −1) in combination with two levels of pH (pH 5.5 and 7.5), and two levels of food availability (high and low). Population level effects of each stressor alone and in combination with the others were investigated using Simocephalus vetulus, a zooplankton species, and Rana pipiens tadpoles (Gosner stage 25), both common to forest ponds and wetlands. Herbicide treatments resulted in significant decreases in survival of both test species as well as reproduction and development time for S. vetulus at levels 5–10× below predicted worst case environmental concentrations (2.6 mg L −1). This laboratory study demonstrates a probable risk of toxic effects of Release ® herbicide which may be significantly increased by low food availability and by low pH at environmentally relevant concentrations.

Root biomass and distribution of a Picea—Abies stand and a Larix—Betula stand in pumiceous Entisols in Japan

Root biomass and root distribution were studied in Entisols derived from the thick deposition of volcanic pumice on Hokkaido Island, Japan, to examine the effect of soil conditions on tree root development. The soil had a thin (<10 cm) A horizon and thick coarse pumiceous gravel layers with low levels of available nutrients and water. Two stands were studied: a Picea glehnii–Abies sachalinensis stand (PA stand) and a Larix kaempferi–Betula platyphylla var. japonica stand (LB stand). The allometric relationships between diameter at breast height (DBH) and aboveground and belowground biomass of these species were obtained to estimate stand biomass. The belowground biomass was small: 30.6 Mg ha−1 for the PA stand and 24.3 Mg ha−1 for the LB stand. The trunk/root ratios of study stands were 4.8 for the PA stand and 4.3 for the LB stand, which were higher than those from previous studies in boreal and temperate forests. All species developed shallow root systems, and fine roots were spread densely in the shallow A horizon, suggesting that physical obstruction by the pumiceous layers and their low levels of available water and nutrients restricted downward root elongation. The high trunk/root ratios of the trees may also have resulted from the limited available rooting space in the study sites.

MAXIMUM SPECIES RICHNESS AT INTERMEDIATE FREQUENCIES OF DISTURBANCE: CONSISTENCY AMONG LEVELS OF PRODUCTIVITY

Development of a mechanistic understanding and predictions of patterns of biodiversity is a central theme in ecology. One of the most influential theories, the intermediate disturbance hypothesis (IDH), predicts maximum diversity at intermediate levels of disturbance frequency. The dynamic equilibrium model (DEM), an extension of the IDH, predicts that the level of productivity determines at what frequency of disturbance maximum diversity occurs. To test, and contrast, the predictions of these two models, a field experiment on marine hard-substratum assemblages was conducted with seven levels of disturbance frequency and three levels of nutrient availability. Consistent with the IDH, maximum diversity, measured as species richness, was observed at an intermediate frequency of disturbance. Despite documented effects on productivity, the relationship between disturbance and diversity was not altered by the nutrient treatments. Thus, in this system the DEM did not improve the understanding of patterns of diversity compared to the IDH. Furthermore, it is suggested that careful consideration of measurements and practical definitions of productivity in natural assemblages is necessary for a rigorous test of the DEM.

Complex interplay between intrinsic and extrinsic drivers of long-term survival trends in southern elephant seals

BackgroundDetermining the relative contribution of intrinsic and extrinsic factors to fluctuations in population size, trends and demographic composition is analytically complex. It is often only possible to examine the combined effects of these factors through measurements made over long periods, spanning an array of population densities or levels of food availability. Using age-structured mark-recapture models and datasets spanning five decades (1950–1999), and two periods of differing relative population density, we estimated age-specific probabilities of survival and examined the combined effects of population density and environmental conditions on juvenile survival of southern elephant seals at Macquarie Island.ResultsFirst-year survival decreased with density during the period of highest population size, and survival increased during years when the Southern Oscillation Index (SOI) anomaly (deviation from a 50-year mean) during the mother's previous foraging trip to sea was positive (i.e., El Niño). However, when environmental stochasticity and density were considered together, the effect of density on first-year survival effectively disappeared. Ignoring density effects also leads to models placing too much emphasis on the environmental conditions prevailing during the naïve pup's first year at sea.ConclusionOur analyses revealed that both the state of the environment and population density combine to modify juvenile survival, but that the degree to which these processes contributed to the variation observed was interactive and complex. This underlines the importance of evaluating the relative contribution of both the intrinsic and extrinsic factors that regulate animal populations because false conclusions regarding the importance of population regulation may be reached if they are examined in isolation.

Comparative reproductive biology of Yezo scallop, Patinopecten yessoensis, under two different culture systems on the east coast of Korea

The annual gametogenesis of Yezo scallop, Patinopecten yessoensis, raised in suspended-hanging (SHCS) and bottom-sowing culture systems (BSCS) on the east coast of Korea was investigated over 2 years. Gametogenesis was initiated in October, when the surface water temperature reached 18 °C. The gametes matured fully and were ready for spawning in March and early April. Spawning occurred from late March to late May, when the water temperature rose from 7 °C to 11 °C. The gonado-somatic index (GSI), a ratio of gonad weight to total tissue weight, ranged from 3.05 (September) to 23.11 (April) for SHCS scallops and from 3.02 (August) to 20.30 (April) for BSCS scallops. The GSI of SHCS scallops was significantly higher ( P < 0.05) than that of BSCS scallops during the first reproductive season, but not the next spawning season. SHCS scallops also maintained a significantly higher condition factor (CF) than that of BSCS scallops ( P > 0.05) throughout most of the period, indicating that the SHCS may provide better growth and reproductive conditions. The higher GSI of SHCS scallops in the first spawning season may have resulted from different levels of food availability and the stocking size of the spats.

Interpopulation variation in life‐history traits of Poeciliopsis prolifica: implications for the study of placental evolution

Placental reproduction is widespread across vertebrate taxa, but little is known about its life-history correlates and putative adaptive value. We studied variation in life-history traits in two populations of the placental poeciliid fish Poeciliopsis prolifica to determine whether differences in post-fertilization maternal provisioning to embryos have a genetic basis and how food availability affects reproduction. Life histories were characterized for wild-caught females and for second-generation lab-born females raised under two levels of food availability. We found that the two populations did not differ significantly in the wild for any life-history traits except for the lipid dry weight in females and in embryos at an advanced stage of development. When environmental effects were experimentally controlled, however, populations exhibited significant differences in several traits, including the degree of maternal provisioning to embryos. Food availability significantly affected female size at first parturition, brood size and offspring dry weight at birth. Altogether, these results demonstrate that population differences in maternal provisioning and other life-history traits have a genetic basis and show a plastic response to food availability. We infer that phenotypic plasticity may mask population differences in the field. In addition, when comparing life-history patterns in these two populations with known patterns in placental and non-placental poeciliids, our results support the hypotheses that placentation is an adaptive reproductive strategy under high-resource conditions but that it may represent a cost under low-food conditions. Finally, our results highlight that age at maturity and reproductive allotment may be key life-history traits accompanying placental evolution.

Managing insect pests in Eucalyptus globulus (Labill.) plantations in Victoria using insecticide tablets at establishment

Summary We studied the effects of fertiliser and insecticide delivered by tablets on defoliation and growth of Eucalyptus globulus in plantations near Meredith in west-central Victoria to determine whether improved foliage retention and growth were conferred by the insecticide and/or fertiliser components of the tablet. Trees at the study site were variably defoliated by three species of insect from March 2004 to September 2005. In the first year of the study, treatments containing imidacloprid insecticide had significantly less defoliation in both the upper and lower crowns than did treatments containing no insecticide. Treatments containing both insecticide and fertiliser showed increased height growth, most likely as a result of a combination of increased levels of available nutrients and protection from defoliating insects provided by the tablets leading to increased overall vigour. The tablets appear to provide adequate protection to trees for about 1 y after planting, although some protection seems to have remained until the 1.7 y assessment. Further observation is required to determine how long this protection lasts. The implications of the study are significant for eucalypt plantation managers. The application of insecticide and fertiliser in tablets at the time of planting potentially provides a more effective and environmentally safer method of insect control than traditional broadscale insecticide applications during the establishment phase. This could potentially lead to improved growth, yield and general health in the longer term.

Geological controls on natural ecosystem recovery on mine waste in southern New Zealand

Slopes of an abandoned waste rock at Wangaloa coal mine, south-east New Zealand, have naturally developed variable vegetation cover over the last 40–60 years. Three distinct areas of revegetation can clearly be identified: dense cover, patchy cover, and largely unvegetated, and the differences in revegetation success are directly related to the physical properties of different rock types making up the waste rock substrate. The colonizing plants have become established in largely unweathered rock with essentially no soil development. Quartz gravel and siltstone waste rock are the two principal rock types forming substrates for revegetation. The quartz gravel has clasts up to 3 cm, and was derived from the coal-bearing sequence. Siltstone was largely derived from a Quaternary loess cap on the coal mine area. These two substrates have similar mineral contents, and this mineral material provides the low level of available nutrients. However, there is little difference in nutrient status or trace element load of the different substrates, and differences in cohesion, moisture content, and proportion of quartz pebbles control revegetation success. Finer grained matrix has been flushed from quartz gravel waste rock by rain water, leaving a dry surface armour layer of quartz pebbles. This surface layer inhibits plant establishment, so quartz gravel waste rock remains largely unvegetated. Erosion creates deep rills, and steep surfaces creep downslope. In contrast, full vegetation cover was established on the siltstone waste rock that was cohesive and did not erode. Patchy revegetation was localized by siltstone in mixed quartz gravel and siltstone substrate. Invertebrate diversity and distribution were closely linked to the spatial patterns of revegetation. The rate of revegetation and ecosystem recovery was primarily dependent on the proportion of siltstone waste rock in the last dumped truck load. A quartz pebble content <15% is optimal for plant establishment.

Germination and seedling survival in fens undergoing succession

We studied mechanisms of vegetation change in fens subject to succession from open water to floating mats and finally herbaceous rich-fens. Earlier research showed that these systems are characterized by transient seed banks. Our main question was whether seedlings of later successional fen stages are already present in earlier stages, remaining subordinate in the vegetation until conditions become suitable for them. If, however, conditions during succession change in a way that only a limited set of species can survive as seedlings during each of the successional stages, no seedling bank will exist. The transient character of the seeds would then imply that seeds will not germinate and will subsequently die and that seeds that have germinated in the “wrong” stage will not become established. We hypothesized that: (1) germination and seedling survival of fen species are significantly better in the successional fen stage for which these species are characteristic, (2) as a consequence no seedling banks occur in these fens. In a field experiment, seeds of five characteristic fen species in the standing vegetation of three successional fen stages i.e. raft fen, quaking fen and rich fen were sown in each of these stages in a turf pond in the Tienhoven area, The Netherlands. Germination and seedling survival were measured over two growing seasons together with environmental variables. Germination was higher in the “own” stage for all species groups as was survival for quaking fen species and rich fen species. For both these stages, percentage of germination and survival of four out of five characteristic species were significantly higher in the “own” stage. Germination and survival can be considered stage-dependent and it was concluded that seedling banks do not exist in these fens. Site-specific environmental variables act as a sieve and differentiate on species presence already during early life history stages. We found clues that the environmental sieve acts at the level of nutrient availability, tolerance for high sulphide concentration and light climate. Because of the transient seed bank and absence of a seedling bank in these fen wetlands, successful establishment of species necessitates a continuous dispersal of characteristic species until the environmental conditions permit establishment. This also implies that species of the whole successional sere should be present within dispersal distance.

Nutrients and the Germ Line

In Drosophila , growth in the germ line and its surrounding somatic follicle cells responds to the level of available nutrients. Insulin-like peptides produced in the brain are involved in this ovarian response to nutrition, but the mechanism of action is unknown. Using methods for the induction of insulin receptor mutant clones and analyzing mosaic ovarioles, LaFever and Drummond-Barbosa show that these insulin-like peptides directly affect the germline stem cells by regulating their rate of division and the rate of cyst growth. In contrast, follicle cells do not respond directly to insulin signals but instead receive a signal from the germ cells for coordinated growth. L. LaFever, D. Drummond-Barbosa, Direct control of germline stem cell division and cyst growth by neural insulin in Drosophila . Science 309 , 1071-1073 (2005). [Abstract] [Full Text]

Potential for Using Plant Xylem Sap to Evaluate Inorganic Nutrient Availability in Soil

To examine the availability of nutrients in soil, chemical extraction methods are commonly used. However, such methods require different extractant solutions depending on the types of soil and nutrients being assayed, making it difficult to assay multiple components simultaneously and compare analytical values. We proposed an alternative method, consisting of the collection of xylem sap exuded from plant stems by employing plant roots as a tool for evaluating the levels of available nutrients in soil. We designated this method as the “xylem sap method.” We tested the effectiveness of this method by growing Luffa cylindrica Roem. seedlings for pre-determined periods of time in pots containing culture medium, removing the aerial parts, and collecting the xylem sap from the cut ends. In a sand culture medium, in which all the nutrients provided were considered to be present in an instantly available form, the concentrations of the nutrients in the xylem sap were found to be proportional to those of the nutrients in the culture solution supplied to the medium, confirming that this technique gives a good index of nutrient availability in the rhizosphere. Furthermore, the contents of the nutrients in the xylem sap were proportional to those of the nutrients accumulated in shoots during the growth period. This shows that, at the seedling stage, nutrient uptake by the aerial parts of L. cylindrica during the growth period exactly mirrors the contents in the xylem sap. It was further confirmed that the nutrient contents in the xylem sap were similarly representative of the nutritional status of the plant. However, in a soilbased culture medium, the increase in the total amount of phosphorus and micronutrients in the medium was not reflected in the xylem sap. This was in agreement with existing findings that concentrations of certain specific nutrients are maintained at a fairly steady level in the plant, irrespective of their availability in soluble form in soil. Thus, we concluded that changes in most nutrient concentrations in the xylem sap corresponded to changes in the behavior and availability of nutrients in soil and that the xylem sap method could be used as an accurate indicator of the availability of most nutrients in soil.

Biomass allocation and leaf chemical defence in defoliated seedlings of Quercus serrata with respect to carbon-nitrogen balance.

Both nutrient availability and defoliation affect the carbon-nutrient balance in plants, which in turn influences biomass allocation (e.g. shoot-to-root ratio) and leaf chemical composition (concentration of nitrogen and secondary compounds). In this study it is questioned whether defoliation alters biomass allocation and chemical defence in a similar fashion to the response to nutrient deficiency. Current-year seedlings of Quercus serrata were grown with or without removal of all leaves at three levels of nutrient availability. Plant nitrogen concentration (PNC), a measure of the carbon-nutrient balance in the plant, significantly decreased immediately after defoliation because leaves had higher nitrogen concentrations than stems and roots. However, PNC recovered to levels similar to or higher than that of control plants in 3 or 6 weeks after the defoliation. Nitrogen concentration of leaves produced after defoliation was significantly higher than leaf nitrogen concentration of control leaves. Leaf mass per plant mass (leaf mass ratio, LMR) was positively correlated with PNC but the relationship was significantly different between defoliated and control plants. When compared at the same PNC, defoliated plants had a lower LMR. However, the ratio of the leaf to root tissues that were newly produced after defoliation as a function of PNC did not differ between defoliated and control plants. Defoliated plants had a significantly lower concentration of total phenolics and condensed tannins. Across defoliated and control plants, the leaf tannin concentration was negatively correlated with the leaf nitrogen concentration, suggesting that the amount of carbon-based defensive compounds was controlled by the carbon-nutrient balance at the leaf level. Defoliation alters biomass allocation and chemical defence through the carbon-nutrient balance at the plant and at the leaf level, respectively.

Responses of Garlic (Allium Sativum L.) to Varying Fertilization Levels and Nutrient Ratios

Garlic can be considered a typical vegetable crop in Hungary, mostly produced on relatively small family farms. Farmers often find it difficult to develop profitable production, and there are still several important questions to be solved, including effective plant protection and nutrient management. A pot experiment was carried out under greenhouse conditions to study the responses of garlic to varying fertilizer sources and nutrient ratios in 15 treatment combinations. Three increasing levels of N‐P2O5‐K2O having a ratio of 1∶0.5∶1.2 with additions of Ca, Mg, S, or CaCO3 were studied in four replicates. Three garlic cloves were planted in pots containing 2 kg of a meadow soil from southeastern Hungary (Fluvaquentic Endoaquoll) having low levels of available nutrients. Plants were grown for 191 days DAP (up to the growth stage of five to seven leaves per plant). At harvest, average plant height, fresh and dry matter (DM) production, shoot to root ratios of plants, as well as nutrient concentrations (macro‐ and microelements) were determined. From the results of the experiment, it was evident that favorable effects of plants to increasing nutrient levels could be observed. Responses of garlic showed relatively high nutrient requirements of plants at the early vegetative period. Highest DM of shoots and roots were obtained with the N3P3K3S3 treatment (226.1 and 204.6% of the control). On the other hand, higher rates of chloride had an unfavorable effect both on fresh and DM weight of plants. Nutrient concentrations also responded to variable fertilizer rates and ratios. Nitrogen concentrations showed similarities to sufficiency ranges found in literature. These values may be used for diagnostic purposes.

Trace Elements in Developing Countries Using South Africa as a Case Study

In industrial countries, micronutrients and trace elements have been well researched. In developing countries, however, human nutrient deficiencies are immense due to poor people having insufficient quantity and variety of high‐quality nutrient‐rich food. The situation is further aggravated by low levels of available nutrients in the soils of some rural areas. Toxicity problems are also poorly studied and often go unnoticed. Some examples of the extent of the need in developing countries are presented by using South Africa as a case study. Soil and plant analysis plays an important role in finding solutions to the problem in developing countries. Better cooperation between different disciplines is urgently required to find more sustainable solutions. Furthermore, attention needs to be given to information access in developing countries.

Food Safety Problems in the World and in Turkey: Solutions Offered from the Perspective of Social Responsibility

At the beginning of the new millennium, looking through national / international perspectives and analysing different projections and conclusions, investigation of future, interrogation of systems and ourselves will be useful. It is necessary to talk about the past and the future in a global perspective when the world population is more than 6 billion and expected to increase around another 2 billion in the next 25 years. Natural resources are limited instead of increased population in the world around. However the growth of technology and communication level, there are so many hazard factors in the life for many developing countries. Simply maintaining current levels of food availability will require rapid production increases without destroying natural resources. Having a good nutritional status for all human societies, everybody must have to think “us” as instead of “myself”. The world has expanded beyond the global village to include the global market where there is ever‐increasing mobility of capital, labour and goods, in the recent years. Globalisation is not only a question of size, but also of kind: it is inextricably linked to privatisation. It stimulated major economic restructuring in both developed and developing countries, and has greatly changed the balance of public and private sectors. Mostly agricultural production for export is seen as one of the driving forces of development. Harmonisation through the setting of international regulations and standards still needs considerable efforts. So that potential benefits and defects, the outcomes of globalisations are mixed and also demographic and production relationship correlations are changed dramatically. In the world natural food and water sources have been reduced, when population increased speedily and environments pollution has become dramatic. In spite of urbanisation the majorities are in rural areas. The information revolutions and scientific / technological challenges also created a major difference between developed and developing countries. Genetically modified organisms and foods are the most important question at this time in the world. Again the differences about sharing chance of the sources between rich and poor countries are another important inequity. “Food insecurity” means that “lacking access to sufficient amounts of safe and nutritious food and are therefore not consuming enough for an active and healthy life”. There are so many reasons for the unavailability of food, inadequate purchasing power or inappropriate utilisation at household level. The linkages between demographic motivations, poverty and environmental degradation, their relationships and implications according to the development programs and planning will try to be discussed in this article. Nutritional and energy requirements, some nutritional deficiencies, reflections on the commercial life, food security programs, and better information systems on “Food Insecurity and Vulnerability (FIVIMS)”, “National Nutrition Country Profiles (NFC)”, farseeing of UN's, Codex Alimentarius Commission (CAC) and World Trade Organisation (WTO) will be summarised. Also it is planned to make small statistical tour on the national and international past, status, and near future on problems and expected reflections, some of the solution offers are improving strategies and increasing consciousness to consumers, developments of health ‐ agriculture — education politics will be summarised. Governmental responsibilities and financial supports will try to be discussed. Finding food, improving life, preparing a better world must be a primer responsibility for all countries, governments, sectors and for everybody in this millennium.