Different Levels Of Fertility Research Articles

Root and shoot studies of summer cowpea (Vigna unguiculata) and baby corn (Zea mays) under intercropping system with different levels of fertility and stress-mitigating chemicals

An experiment was conducted during summer seasons of 2019 and 2020 at College of Agriculture (Agriculture University, Kota), Ummedganj, Rajasthan, to study the root and shoot of summer cowpea [Vigna unguiculata (L.) Walp.] and baby corn (Zea mays L.) under intercropping system with different levels of fertility and stress-mitigating chemicals. The experiment was laid out in a split-split plot design with 4 replications having 30 treatment combinations with 5 intercropping systems [sole cowpea; sole baby corn; cowpea + baby corn (2:1); cowpea + baby corn (3:1); and cowpea + baby corn (4:1)] in the main plot and 3 fertility levels, viz. 100; 125; and 150% RDF (Recommended dose of fertilizer) in subplot and 2 stress mitigating chemicals (0.5% CaCl2 and 1% KNO3 at flowering and pod development stage of cowpea) in sub-sub plot. Results revealed significant increase in shoot weight, root weight, root-to-shoot ratio, cowpea equivalent yield (CEY) and number and dry weight of nodules in 2:1 row cowpea + baby corn intercropping system over other row ratios. The 2:1 row ratio significantly increased root:shoot ratio of cowpea by 20.9, 15.2, and 7.3% over sole cowpea, 4:1 and 3:1 row ratio, respectively, and resulted in the highest root-to-shoot ratio for baby corn, recording 18.3, 14.5, and 6.8% increase over sole baby corn, 4:1, and 3:1 row ratios of cowpea and baby corn, respectively. Further shoot weight, root weight, root:shoot ratio in cowpea and baby corn, CEY and the number and dry weight of nodules in cowpea exhibited a notable increase in 150% RDF as compared to lower fertility levels (100 and 125% RDF). Applying 150% RDF resulted in a significantly higher root:shoot ratio for both cowpea and baby corn, with increases of 11.3 and 4.5% over 100 and 125% RDF for cowpea, and 11.6 and 5.5% over 100 and 125% RDF for baby corn, respectively. Foliar application of 0.5% CaCl2 at the flowering and pod-developing stages significantly augmented all the aforementioned parameters for both cowpea and baby corn.

Effect of Fertility Levels and Boron on the Development and Production of Cauliflower

A field experiment consisting five levels of fertility and four levels of boron in RBD with three replications was conducted at Horticulture Farm, SKNAU, (Jaipur) during Rabi season. The findings showed that different levels of fertility used to have a significant impact on the growth, yield of cauliflower. Plant height at 30 and 60 DAT, the number of leaves per plant at 30 and 60 DAT and leaf area were all highest when 75% RDF through inorganic fertilizers and 25% RDF through vermicompost were applied. Also, it was found that the application of 50% RDF using inorganic fertilizers and 50% RDF through vermicompost treatment resulted in the highest curd yield per plot and curd yield per ha (190.89 q/ha).

Directions, methods and results of rye (Secale cereale L.) breeding in Belarus

At the present stage of science development, breeding of new varieties of plants using modern, including molecular methods, is one of the main links in the intensification of the agricultural industry. Rye is no exception in this respect. This is a traditional strategic crop for Belarus, that largely determines the country’s food security. In the paper, in a historical context, the main achievements in breeding of rye varieties for different uses are outlined. The main approaches are described, including: screening of the world diversity of winter rye in the conditions of Belarus; use of methods of experimental polyploidy, hybridization, stabilizing selection, molecular-genetic methods and techniques. Development and application of modern methods have allowed a number of genetic mechanisms and regularities to be discovered, which, in turn, has significantly increased the efficiency of rye breeding in different directions (population and heterosis). At present, RUE “Scientific and Practical Center of the NAS of Belarus for Arable Farming”, State Scientific Institution “Institute of Genetics and Cytology of the NAS of Belarus”, as well as jointly with other institutions have developed new breeding methods, including molecular-genetic ones, which is especially important for increasing the efficiency of obtaining competitive varieties. Significant results have been achieved on the use of the effect of heterosis based on cytoplasmic male sterility (CMS). To date, a system of highly productive competitive rye varieties has been created for soils of different levels of fertility: population tetraploid and diploid, as well as F1 hybrids – LoBel-103, Galinka, Plisa, and Belgi.

Antioxidant properties and transcriptome of cauda epididymis with different levels of fertility in Hu lambs

Oxidative stress damages the structure of sperm and affects its fertility. Further maturation and storage of spermatozoa occur in the epididymis. Thus, a balanced environment between free-radical production and the antioxidant–enzyme system is important. This study aimed to investigate differences in antioxidative activity in epididymis between high and low fertility levels of Hu sheep. A total of 179 Hu ram lambs aged 56 days were fed up to 6 months in the same environment. After feeding trial, all rams were slaughtered. According to the epididymis weight, cauda sperm concentration, and histo-morphological observation, 18 individuals were selected and divided into low fertility (n = 9) and high fertility (n = 9) groups. The RNA sequencing results showed 1404 differentially expressed genes (DEGs), with 735 genes upregulated and 669 genes downregulated in the high fertility group compared with the low fertility group. Sixteen DEGs related to lipid metabolism and oxidative stress, including GPX3, GPX5, LRP1, PLCB1, CRISP2, BSPH1, and ACSBG1, were screened by qPCR, and results were correlated well with the sequencing data. Antioxidative indices such as total antioxidant capacity (21.29 ± 5.97 vs. 30.23 ± 4.56 μM/gprot) and glutathione peroxidase (39.75 ± 7.61 vs. 68.84 ± 12.51 U/mgprot) increased in the high fertility group. However, the relative expression of mtDNA and malondialdehyde concentration (0.75 ± 0.15 vs. 0.54 ± 0.10 nmol/mgprot) and the reactive oxygen species (ROS) content significantly decreased (P < 0.05). Therefore, epididymis from high-fertility group had strong antioxidative activity and protected spermatozoa from ROS.

Stud-breeding work in sheep breeding based on cytogenetic monitoring

The article presents the results of the cytogenetic monitoring in the breeding, selection and reproduction of sheep in the ecological conditions of Ukraine. A cytogenetic analysis of sheep with low and high vigor and different levels of fertility was carried out. In the ecological conditions of Ukraine, the individual level of chromosomal abnormalities in all the studied animals of the Tsigai breed and prekos is within the natural background. No translocations were found. Among the violations, such as single and paired fragments, hypo- and hyperploidy (mainly hypoploidy), polyploidy were encountered. The maximum average level of chromosomal abnormalities was found in local lambs (5.5 ±1.73%). The minimum average level of chromosomal abnormalities (2.0 ±1.41%) was recorded in lambs with high growth intensity. Among the structural changes, mutations of the chromosomal type prevailed in the 3-year-old group of rams - 0.46%, in the 8-year-old group - 0.59%. Chromatid disturbances were 0.37% and 0.34%, respectively. The average level of chromosomal abnormalities in rams by groups was 0.84 ±0.14 and 0.93 ±0.13, respectively. In the group of ewes with low fertility (n = 4), the level of chromosomal abnormalities was 3.5%, which is lower than ewes (n = 7) with high fertility by 0.79%.

Potential N mineralization and availability to maize in black soils in response to soil fertility improvement in Northeast China

Understanding the soil nitrogen (N) mineralization potential (N0) and crop N availability during the growing season is essential for improving nitrogen use efficiency (NUE) and preventing over-fertilization, which lead to negative environmental impacts. Five black soils with different levels of fertility were selected in Northeast China. The N0 and kinetics of these soils were estimated through laboratory experiments at different incubation temperatures (15, 25, and 35 °C). N mineralization dynamics were simulated using field soil temperature according to the incubation results. Moreover, the N uptake dynamics of maize were simulated according to the literature. Compared with the very low-fertility soils, the cumulative mineralized nitrogen increased under all incubation temperatures (15, 25, and 35 °C), by 48–136%, 8–61%, and 24–59%, respectively, in the medium- and high-fertility soils. The highest N0 values (96.90, 115.31, and 121.33 mg/kg at the three different temperatures) were recorded in the very high-fertility soils. The soil N mineralization dynamics and N uptake of maize in the growing season were highly consistent over time, although the soil N supply could not meet the maize growth requirements. The higher the soil fertility, the lower the N fertilizer requirement. Different fertilizer strategies were developed based on the cumulative mineralized N, N uptake by maize, and NUE in soils with different fertility levels. We suggested a reduction of 50–65 kg N/ha in N fertilizer in the two highest fertility soils. This study provided basic data to reduce chemical N fertilizer to improve NUE and reduce negative environmental impacts.

Sole-Source LED Lighting and Fertility Impact Shoot and Root Tissue Mineral Elements in Chinese Kale (Brassica oleracea var. alboglabra)

The current study investigated the impacts of light quality and different levels of fertility on mineral nutrient concentrations in the shoot and root tissues of Chinese kale (Brassica oleracea var. alboglabra). “Green Lance” Chinese kale was grown under: (1) fluorescent/incandescent light; (2) 10% blue (447 ± 5 nm)/90% red (627 ± 5 nm) light emitting diode (LED) light; (3) 20% blue/80% red LED light; and (4) 40% blue/60% red LED light as sole-source lighting at two different levels of fertility. All plants were harvested 30 days after seeding and shoot and root tissues were analyzed for mineral nutrients. Lighting and fertility interacted to influence kale shoot and root mineral nutrient concentrations. The results indicate that sole-source LED lighting used in production can impact the mineral nutritional values of baby leafy greens now popular for the packaged market. This is evident in the current and previous studies in which lighting affects biomass and indirectly affects mineral nutrient concentrations.

Agen Based Modeling for Corn Supply Chain Risks Identification and Sales Negotiation in PTPN VIII

PTPN VIII is a state-owned company in West Java cultivating several kinds of commodities, and still have three marginal farmlands with a total size of 3000 hectares open for investment for corn. The type of corn that would be produced is corn feed for poultry needs. Three agents are involved in this agent-based model: the farmers (or cooperatives), PTPN VIII, and the buyers of the corn yields. All agents face risks in doing their businesses which hamper or reduce their probability of achieving their business goals. The potential risks are identified using fuzzy reasoning method. The three blocks of farmland have different levels of fertility. Farmers are expected to compete for the hunt of farmland to rent for cultivating corns, until their funds run out. They must prepare the land, procure their best corn seeds, plant and maintain the crops, and eventually harvest, dry and sell their corn yield. The dryness of the corn grains dictates the selling price. The buyers will buy the corns until their demands are fulfilled for the particular season. There will be a negotiation process between agents to reach an agreement. Each agent seeks to achieve its goal. This is why agent-based modelling is employed. Netlogo software is used to develop the model. Based on fuzzy reasoning method the obtained result shows that the most potential risk is quality risk. The negotiation results show that when both buyer and seller experience heightened degree of risk appetite, the shortest negotiations are achieved.

Phosphorus uptake and phosphorus use efficiency of high zinc rice genotypes of clay soil under different levels of fertility

Phosphorus (P) is necessary by crop plants for many physiological and biochemical functions. Consciousness of phosphorus uptake and its use by crop plants is essential for management of this essential nutrient. A field experiment was conducted during Kharif season, 2013 at the Research cum Instructional Farm, Indira Gandhi Krishi Vishwavidhyalaya, Raipur (C.G), to determine P uptake and use efficiency of high zinc containing rice genotypes in lowland clay soil order belongs to the Vertisols. Plant samples were collected at maturity stage. Rice (Oryza sativa L.) is one of the most important staple food crops for approximately half of the global world. The experiment was carried out in split-plot design with three replications having four fertility levels in main plots and twelve varieties in sub plots. The highest total phosphorus uptake was recorded by R-1033-968-1(ABL) (G2), followed by the genotype R-RF-31(ABL) (G1) that was statistically at par with Chandrahasini (G12) and significantly the lowest phosphorus uptake was obtained by SWARNA×MOROBRAKEN-23 (G3). Phosphorus uptake increased with increasing fertilizer application from low to high fertility level. Application of high fertility level produced higher phosphorus uptake (18.645kg ha-1) followed by medium fertility level (17.249kg ha-1) low in lower fertility level (15.110kg ha-1) and lowest (11.081 ha-1) in control. Phosphorus use efficiency ranged from 17.80 to 36.70 90 per cent with overall mean value of 27.00 per cent. The genotype R-1033-968-1(ABL) was recorded maximum PUE and the lowest by Improve Chitimutalya. The doses of phosphorus application affected P use efficiency. It was higher in case of low fertility level than that of medium and high fertility level.

O caminho da saúde sexual e reprodutiva na América Latina: uma análise temporal de indicadores para cinco países da Região

Apresenta-se a evolução do padrão reprodutivo de diferentes países da América Latina com níveis de fecundidade distintos, procurando entender se a Região está tornando-se mais homogênea em termos de comportamento reprodutivo. Utilizam-se como indicadores desse padrão: proporção de mulheres sem filhos, idade mediana à primeira união e ao ter o primeiro filho e presença de filho ao usar contracepção pela primeira vez. Os dados provêm de pesquisas sobre saúde reprodutiva de Brasil, Colômbia, El Salvador, Peru, e República Dominicana em três pontos no tempo: décadas de 80 e 90 e início dos anos 2000 segundo idade e escolaridade. Os resultados mostram que as diferenças estão diminuindo entre os países com a proximidade dos níveis de fecundidade, mas ainda permanecem brechas por escolaridade que sugerem ampliar-se dentro dos países. Os resultados oferecem importantes insumos para entender os trajetos delineados por diferentes gerações nos países da Região no que se refere ao padrão reprodutivo.

Evaluation of the effect of laboratory methods on semen analysis and breeding soundness examination (BSE) classification in stallions

The stallion Breeding Soundness Examination (BSE), as proposed by the Society for Theriogenology, recommends that a stallion produce a minimum of one billion progressively motile, morphologically normal sperm (PMMNS) in the second of two ejaculates collected 1 h apart to be classified as a Satisfactory Prospective Breeder. With this in mind, the first objective of this study was to determine if the classification outcome of the traditional BSE differs depending on the methods used to evaluate sperm motility, morphology and concentration. We hypothesized that application of Computer Assisted Sperm Motion Analysis (CASA) and Differential Interference Contrast (DIC) microscopy to stallion semen evaluation would yield a more conservative estimate of the number of PMMNS. If this hypothesis is correct, then the use of CASA and DIC microscopy for semen evaluation would result in significantly fewer stallions meeting the historical standards for classification as a Satisfactory Prospective Breeder. Additionally, we determined whether the use of these modern technologies resulted in more accurate prediction of the actual fertility of a stallion compared to the use of more traditional technologies. Our results support the hypothesis that modern semen analysis techniques (including CASA and DIC microscopy) result in more conservative estimates of the number of PMMNS when compared to standard semen analysis techniques. As a result, the choice of methods used for semen analysis may impact the outcome of the traditional BSE. However, none of the methodologies used in this study reliably predicted different levels of fertility among this group of moderately to highly fertile stallions within the context of the traditional BSE. Additionally, the only individual semen measure that was significantly correlated with fertility was the percentage of morphologically normal sperm as determined using DIC microscopy. These results caution against strict use of the traditional ‘cutoff’ of 1 billion PMMNS for classification of breeding potential, particularly when attempting to differentiate between moderately and highly fertile stallions and regardless of the laboratory methods employed for semen analysis.

Применение модели Хассела для прогнозирования плотности популяции золотистой картофельной нематоды после выращивания глободероустойчивого сорта картофеля

The purpose of the research is evaluation the possibility of application the Hassell model for prediction the dynamics of population density of golden nematode of potato in the ground after growing Globodera resistant variety of potato in the single-crop. Materials and methods . For the research database of population density of golden nematode of potato (amount of ootids and larvae) was used on the three plots where amenable varieties of potato were grown and one plot where Globodera resistant variety of potato Kardinal was grown in the Kaluga Region within 14 years (1979–1993). Non-linear least-squares method which is the version of least-squares method for non-linear systems was used as the method for evaluation the model parameters. Toolset of search for solution in the program Excel was used for analysis. Results and discussion . Hassell model for prediction the dynamics of population density of golden nematode of potato in the ground after growing Globodera resistant variety of potato in the single-crop demonstrated high confidence. (R 2 = 0.94). Based on the Hassell model for development golden nematode of potato population in plot soil with growing nematode resistant variety modeling of introduction of Globodera resistant variety was conducted for different initial amount of golden nematode of potato and different levels of fertility of soil: low, average, high. Hassell model has confirmed that it is the most multifunctional in the category of discrete one-period models for prediction dynamics of population density of golden nematode of potato in the ground and permits to predict the amount of golden nematode of potato for agrobiocenosis with single-crop of potato of amenable and Globodera resistant varieties.

Effect of education on age at first birth in Semnan, Hormozgan, Kohkiloye and Booir Ahmad provinces, Iran

Introduction: Iran experienced a dramatic fertility decline during recent decades. There was also an indication of a shift towards later childbearing from 2000. Past research on fertility has shown that the education variable is the most important determinant of fertility behaviors. However, the impact of education on fertility timing in Iran has been less considered. Methods: In a cross sectional study 1149 ever-married women aged 35-44 in three provinces with different levels of fertility, Semnan, Hormozgan, Kohkiluye and Booir Ahmad, were selected by the multi-stage cluster sampling method. A structured questionnaire instrument was used for data collection. Kaplan-Meier estimates and Cox Regression were used to analyze data. Results: Kaplan-Meier estimates in three province show significantly different between age at first birth and womenrs educational level (P<0.05). Mean of age at first birth among university educated women in Semnan, Hormozgan, and Kohkiloye and Booir Ahmad provinces was 23.5, 24.6 and 24.29 respectively. Results of the multivariate analysis using the Cox Proportional Hazard model show also that university education is a significant factor in reducing the risk a first birth in three provinces. However the decreasing impact on the risk of first birth in Semnan is lower than other provinces.n Conclusion: Womenrs access to education in Iran is a substantial contributornof postponement of childbearing and higher educated women are pioneers in delaying childbearing and reducing fertility in Iran.

Spatial variability of soil potassium in sugarcane areas subjected to the application of vinasse.

When deposited on land the vinasse can promote improvement in fertility, however, often fertilizer application occurs in areas considered homogeneous, without taking into account the variability of the soil. The objective of this study was to evaluate the effect of vinasse application on potassium content in two classes of soils cultivated with sugarcane, and characterize the spatial variability of soil using geostatistical techniques. In the 2010 and 2011 crop year, soil samples were collected from an experimental grid at 0-0.2 and 0.2-0.4 m depth in three soils cultivated with sugarcane, totaling 90 samplings in each grid, for the determination of pH, calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), aluminum (Al) and potential acidity (H + Al). The data have been submitted to analysis of descriptive statistics and the K attribute was subjected to geostatistical analysis. The coefficient of variation indicated medium and high variability of K for the three soils. The results showed that the spatial dependence of K increased in depth to FRce and decreased to PHlv, indicating that the attribute could have followed the pattern of distribution of clay in depth. The investigation of the spatial variability of K on the surface and subsurface soils provided the definition of management zones with different levels of fertility, which can be organized into sub-areas for a more efficient management of the resources and the environment.

Characterization of fertility restoration in alloplasmic lines derived from hybridization of self-fertilized offspring of barley-wheat (Hordeum vulgare L. × Triticum aestivum L.) amphiploid with common wheat varieties Saratovskaya 29 and Pyrotrix 28

The problems of fertility restoration in the progeny of barley-wheat hybrids (H. vulgare × T. aestivum) are explained by incompatibility between the cytoplasm of cultivated barley and the nuclear genome of common wheat. Appropriate models for studying these problems are alloplasmic lines that combine the cytoplasm of barley and the nuclear genome of wheat. In this work, the differences of fertility restoration in alloplasmic common wheat lines (H. vulgare)-T. aestivum were studied depending on the influence of wheat varieties Saratovskaya 29 (Sar29) and Pyrotrix 28 (Pyr28) used to produce these lines. The alloplasmic lines were created using hybrids between the 48-chromosome offspring (Amph1) of the barley-wheat amphiploid H. vulgare (ya-319) × T. aestivum (Sar29) and these wheat varieties. Backcrossing of the Amph1 (2n = 48) × Sar29 hybrid with the wheat variety Sar29 resulted in the complete sterility in the (H. vulgare)-Sar29 line, which suggests the incompatibility of the nuclear genome of the common wheat variety Sar29 with the cytoplasm of H. vulgare. Crossing of Amph1 (2n = 48) with Pyr28 resulted in the restoration of self-fertility in the hybrid with 2n = 44. In the alloplasmic lines (2n = 42) formed based on plants of the self-fertilized generations of this hybrid, the barley chromosomes were eliminated, and recombination between the nuclear genomes of the parental wheat varieties Sar29 and Pyr28 took place. Alloplasmic recombinant lines (H. vulgare)-T. aestivum with different levels of fertility were isolated. As was shown by the SSR analysis, differences in the fertility between these lines are determined by differences in the content of the genetic material from the wheat varieties Sar29 and Pyr28. The complete restoration of fertility in these alloplasmic recombinant lines is accompanied by the formation of a nuclear genome in which the genetic material of Pyr28 significantly prevails. The conclusion is made that the common wheat variety Pyrotrix 28 is a carrier of a gene (or genes), which determines the restoration of common wheat fertility on the cytoplasm of cultivated barley.

Generation and Characterization of Interspecific Hybrids of Lotus uliginosus × Lotus corniculatus

ABSTRACTA method is described for obtaining interspecific hybrids between commercial lines of Lotus uliginosus Schkuhr and Lotus corniculatus L. Hybridization was possible between these species using embryo rescue. Two strategies were used to confirm 40 F1 hybrids, that is, flow cytometry and microsatellite simple sequence repeats (SSRs). The L. uliginosus and L. corniculatus parents have significantly different genome size (2.5 ± 0.02 and 2.22 ± 0.02 pg, respectively) and the offspring from the cross had intermediate values. Two SSR primers were polymorphic between the genotypes tested, TM1150 and EH380069. Maternal effect was detected in L. uliginosus genotypes, as determined by greater frequency of F1 hybrids. Recombinant traits were observed in the F1 hybrid progeny. Ninety F1 hybrids resulting from L. uliginosus × L. corniculatus crosses showed different levels of fertility in the polycross; &lt;3% F1 plants produced more than 1000 seeds without embryo rescue while 10% of plants did not flower the first year. The F1 hybrid plants grown under greenhouse conditions exhibited shoot phenotypes similar to L. uliginosus (maternal) whereas F2 phenotypes were similar to L. corniculatus (paternal) in field trials. Rhizome presence was observed in 60% of F2 hybrid plants. The diameters of the root crowns of these plants, however, were similar to that of L. corniculatus.

The CC-allele of the PvuII polymorphic variant in intron 1 of the α-estrogen receptor gene is significantly more prevalent among infertile women at risk of premature ovarian aging

To study the distribution of a set of polymorphic alleles of genes encoding key regulators of the menstrual cycle in cohorts of women with different levels of fertility. Prospective cohort study. University hospital. Two hundred fertile women, who reported to have conceived within 3 months, 348 women with ongoing menstrual cycles suffering of infertility, and 48 infertile women diagnosed with infertility and premature ovarian failure (POF). Eleven polymorphisms of genes with known associations with surrogate parameters of female ovarian function were analyzed. The prevalence of polymorphic alleles in the three distinct cohorts after adjustment for age. The distributions of the allelic variants were compared with the fertility status of the recruited women. Using age-adjusted logistic regression analysis and the Bonferroni correction for multiple corrections, the CC-allele of the PvuII polymorphic variant in intron 1 of the ESR1 gene was twice as prevalent among women suffering from infertility. None of the other polymorphisms were distributed differently among the three cohorts. The ESR1-PvuII polymorphism emerges as a potential candidate for the early prediction of infertility due to premature ovarian aging.

Crescimento inicial de Dimorphandra wilsonii (Fabaceae - Caesalpinioideae) em diferentes condições de fertilidade em solo de cerrado

Dimorphandra wilsonii Rizz. é uma espécie arbórea criticamente ameaçada de extinção. Foi descrita para áreas de maior fertilidade no Domínio do cerrado; entretanto, atualmente ocorre em áreas isoladas e de baixa fertilidade natural. Com o objetivo de avaliar a adaptação desta espécie a condições de oligotrofia, plantas foram cultivadas em casa de vegetação em solo destas áreas oligotróficas, mas com diferentes níveis de fertilidade. A partir da análise de fertilidade do solo foram definidas as doses de macronutrientes (NPK) e a dose de calcário a serem utilizadas nos tratamentos que se constituíram de dois níveis de calagem e três níveis de adubação. Após 220 dias do plantio, os tratamentos que aumentaram significativamente o crescimento foram aqueles que receberam adubação com a dose indicada de NPK em solo não corrigido pela calagem e aquele que teve o solo calado e adubado com duas vezes a dose indicada de NPK. A calagem por si só não promoveu maior crescimento, mas propiciou respostas crescentes de crescimento a níveis crescentes de disponibilidade de nutrientes. Foram encontrados nódulos radiculares em todos os tratamentos, e os resultados permitiram concluir que a espécie apresenta requerimento nutricional coerente com sua área de origem no Domínio do Cerrado. Também foi possível ressaltar a fixação biológica de nitrogênio, incomum em Caesalpinioideae, como estratégia adaptativa para crescimento em áreas com baixa oferta de nutrientes.

The impact of social policy on fertility: evidence from Switzerland

Variation in fertility rates, across both countries and time, is sometimes explained with reference to specific types of social policies. In particular, the recent increase in fertility rates seen in some Nordic countries and in France has been ascribed to these countries' efficient child care systems. One major limitation of these studies is represented by the small number of cases (usually some 22 OECD countries) and the large number of potential determinants of fertility rates, which makes powerful multivariate analysis impossible. This article, while not solving the small-N-many-variables problem, provides additional independent evidence on which to test the hypotheses generated by international comparisons, by looking at variation in fertility rates within Switzerland. Switzerland is a federal country where subnational units (the cantons) enjoy almost total autonomy in matters of family policy and are experiencing very different levels of fertility. The analysis basically confirms the findings of previous studies, highlighting the importance of child care but also of the level of family benefits as determinants of fertility rates.

Distribuição e abundância de espécies arbóreas em cerradões no Pantanal, Estado do Mato Grosso do Sul, Brasil

The woodland savannas occupy non-flooding areas in the Pantanal wetlands and are an important resource for regional economy. Even though, wood from woodland savannas are cut and used for fences, pens, and sheds in the farm, there are not much information from woodland savannas regarding sustainable uses and conservation. This study investigated the abundance, the distribution of species and correlations with soil fertility in six areas of woodland savanna (cerradao) in Southern Pantanal wetlands. The survey was accomplished by means of 30 point-centred quarters in each area, totalling 120 trees sampled with the circumference at breast height (CBH) > 15 cm. The association between floristic composition, abundance of species and soil fertility were determined by the principal components analysis (PCA). Savanna forests are very heterogeneous, presenting different levels of soil fertility as well as vegetation structure and composition. Two of them were clustered according to soil fertility and vegetation structure, they both presented large stands of the tree Qualea grandiflora Mart., species that seems to prefer soil with larger phosphorous quantity. Two other areas of savanna forests showed similar floristic composition, despite being in areas where the soil presented different levels of fertility, pointing out the human disturbance.