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Crop diversity, particularly cover crops under no-tillage, increases agricultural efficiency in the use of nutrients and the soil carbon management. The objective of the present study was to evaluate the impact of single cover crops and intercropping (MIX) under long-term no-tillage on shoot dry mass (SDM) production, nutrient cycling, soil chemical attributes, and soybean yield in the Cerrado of Mato Grosso. The treatments consisted of MC: monocropped; CS1: Crotalaria spectabilis; CS2: Pennisetum glaucum (millet); CS3: Urochloa ruziziensis; CS4: Cajanus cajan (pigeon pea); and MIX: all four crops intercropped (C. spectabilis + P. glaucum + U. ruziziensis + C. cajan). The shoot dry mass of the cover crop was evaluated at 0, 90, 105, 120, 150, 180, and 210 days after cover crop management (CM) (desiccation) in the crop years from 2014/15 to 2020/21. The chemical properties of the soil were evaluated after the 2019/20 soybean crop harvest. SDM accumulation in MIX was approximately 22% higher than that in CS2 and CS3 and 60% higher than that in MC. Soybean yields were 20% higher in MIX, CS3, and CS4 than in MC, corresponding to an increase of approximately 14 bags of soybean. MIX and CS3 improved soil chemical attributes through nutrient cycling and SDM production under long-term no-tillage. MIX, CS3, and CS4 promoted increases in soybean yield after the stabilization phase of the system. The accumulation and release of nutrients by the shoots was an important indicator of nutrient cycling under no-tillage and consequent increases in the yield of soybean in succession.

Made available in DSpace on 2022-05-01T09:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Crop rotations under no-till (NT) have been a strategy to increase soil organic carbon (SOC) and mitigate greenhouse gas (GHG) emissions, enhancing the cropping system efficiency. However, there is still controversy on the role of grasses and legumes, and species diversity and their impacts. This study aimed to assess the GHG emissions, SOC, and Nitrogen (TN) in a soybean production system managed under NT in rotation with different species in the fall-winter and the spring seasons. Main plots during the fall-winter were (1) Triticale (x Triticosecale) and (2) Sunflower (Helianthus annuus). Subplots established in the spring were (a) Sunn hemp (Crotalaria juncea), (b) Sorghum (Sorghum bicolor), (c) Pearl millet (Pennisetum glaucum), plus a (d) Fallow treatment. Soybean was grown every year in the summer, in sub-subplots. The GHG emission was affected according to crop species. In the spring, Sunn hemp emitted more nitrous oxide (N2O) (0.82 kg ha-1) than fallow (0.58 kg ha-1); however, the high C and N inputs by the legume and also other cover crop residues reduced the relative emissions compared with fallow. Growing pearl millet or Sunn hemp as a spring cover crop increases SOC by 7% on average compared with fallow. The N2O emission of Sunn hemp accounted for only 0.28% of the total N accumulated in the legume residues, notably lower than IPCC estimates. In the fall-winter, Triticale increased SOC by 7%, decreased CO2 emission by 18%, and emitted 20% lower GHG to produce the same soybean yield compared with sunflower. Soybean rotation with triticale in fall-winter and Sunn hemp or pearl millet in spring decreases GHG emissions. Our results indicate that the right choice of species in rotation with soybean under NT increases SOC and may offset GHG emissions from tropical soils. It may be an important tool in mitigating potential global warming. São Paulo State University UNESP College of Agricultural Sciences Department of Crop Science, SP Federal University of Paraná UFPR Department of Agronomic Sciences, PR Goiano Federal Institute IF Goiano Department of Agriculture, GO São Paulo State University UNESP College of Agricultural Sciences Department of Crop Science, SP

Made available in DSpace on 2021-06-25T11:09:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Lime and phosphogypsum applications are well-established practices in weathered soils, and their surface application under no-till (NT) can affect soil physical attributes and C and N fractions. This study determined the long-term (10-yr) effects of lime and phosphogypsum applications to the soil surface on soil C and N fractions of a tropical NT field. The experimental design was a randomized block with four treatments and four replications. The following treatments were applied in October 2002, November 2004, and October 2010, respectively: limestone (2,000 kg ha−1), phosphogypsum (2,100 kg ha−1), and limestone (2,000 kg ha−1) plus phosphogypsum (2,100 kg ha−1). In general, after 10 yr of liming, both alone and when associated with phosphogypsum, the cumulative crop straw inputs were increased at least 20% across the years, and the C fractions increased remarkably at different soil depths. Both treatments improved the SOC stocks by 24% (12.5–15.6 Mg ha−1) at 0.1–0.2-m soil depths and by 10% (30.6–33.8 Mg ha−1) at 0–0.2-m soil depths, and in general the soil aggregation at 0–0.4-m soil depths. However, the particulate C and N fractions were reduced at 0–0.05-m soil depth, suggesting a slight response to the transitory trend of soil organic C (SOC) depletion. Liming, both alone and when associated with phosphogypsum, overcame the transitory C pool depletion and improved soil aggregation, soil C fractions, and SOC stocks and could be considered an important factor that drives the sustainability of cropping systems under NT. Federal Univ. of Goiás (UFG) Dep. of Natural Resources and Environmental Sciences Univ. of Illinois Dep. of Crop Science College of Agricultural Science São Paulo State Univ. (UNESP) Dep. of Crop Science College of Agricultural Science São Paulo State Univ. (UNESP) FAPESP: 2011/10493-9 FAPESP: 2013/03683-1 FAPESP: 2013/06733-0 FAPESP: 2013/26669-4 FAPESP: 2014/06175-0

Made available in DSpace on 2021-06-25T10:24:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Aims: Cover crop species selection for soybean (Glycine max) production under no-tillage (NT) management may affect soil organic C sequestration by altering the quantity and quality of C inputs, thereby affecting cropping system sustainability. If so, the underlying mechanisms for such regulation are still unclear. Methods: We assessed changes in soil C and N fractions at 0-0.1 m depth and soil C stock at 0-0.6 m depth during the last three years of dry-season cover cropping in a soybean production system managed with NT for 9 years on a Rhodic Hapludox in Sao Paulo, Brazil. Dry-season management treatments were repeated yearly in a split-plot scheme. Main plots during the fall-winter were (1) ruzigrass (Urochloa ruziziensis), (2) grain sorghum (Sorghum bicolor), and (3) the intercropping of ruzigrass and sorghum. Subplots during spring prior to planting soybean were (a) pearl millet (Pennisetum glaucum), (b) sunn hemp (Crotalaria juncea), and (c) forage sorghum (Sorghum bicolor). Results: Soil C and N fractions were affected according to crop residue characteristics of the rotations. Higher soil C stocks in 2012 and 2015 (7 % an average) were observed at 0.2–0.4 m depth by ruzigrass compared to sorghum. High crop residue input with ruzigrass in the fall-winter sequestered 0.61 Mg C ha− 1 yr− 1 at 0-0.1 m soil depth compared with lower C sequestration using grain sorghum (0.29 Mg C ha− 1 yr− 1). Conclusions: The quantity and quality of crop residues impact its retention on soil surface controlling the dynamics of soil C and N fractions and can be considered relevant for soil C sequestration. These aspects could contribute to the mitigation of atmospheric CO2 in crop production systems. Department of Crop Science College of Agricultural Sciences Sao Paulo State University UNESP, 3780, Avenida Universitaria Department of Soil Science College of Agricultural Sciences Sao Paulo State University UNESP, 3780, Avenida Universitaria Department of Crop and Soil Sciences at North Carolina State University USDA Agricultural Research Service Department of Crop Science College of Agricultural Sciences Sao Paulo State University UNESP, 3780, Avenida Universitaria Department of Soil Science College of Agricultural Sciences Sao Paulo State University UNESP, 3780, Avenida Universitaria

Made available in DSpace on 2020-12-10T20:12:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Sustainability of agriculture with no-tillage (NT) production requires appropriate cover cropping and not a simple and random approach of any cover crop species. However, relatively little is known of the long-term soil surface impacts of different cover crops in rotation with soybean (Glydne max) under NT in the tropics. We evaluated the impacts of different cover crops on soil aggregation, soil organic carbon (C) and nitrogen (N) fractions, and soil microbial activity of a Typic Rhodudalf at the end of 12 years under NT in Sao Paulo state of Brazil. Treatments included main plots during the winter dry season (triticale [x Triticosecale] and sunflower [Helianthus annuus]) and subplots during the spring cover crop season (pearl millet [Pennisetum glaucum], sunn hemp [Crotolaria juncea], forage sorghum [Sorghum bicolor], and fallow with occasional chiseling).All eight of these treatments followed soybean in summer. Winter crop treatments had no effect on soil aggregation, but total organic C and N concentrations were greater (p < 0.05) with triticale than with sunflower. Across depths, soil aggregation and soil C and N fractions were generally enhanced when sunn hemp was cover crop than with fallow in the spring.Triticale followed by sunn hemp provided soil cover and fresh mineralizable residue for improving soil quality in this unfertilized (N) soybean-based cropping system. Our results suggest that maintaining soil cover is important to improve soil aggregation and soil C and N fractions, but also the quality of organic inputs determined by cover crop species is an important factor controlling the dynamics of these soil responses. Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Botucatu, SP, Brazil USDA ARS, Raleigh, NC 27695 USA Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Sao Paulo, Brazil Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Botucatu, SP, Brazil Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Sao Paulo, Brazil FAPESP: 15/23389-6 FAPESP: 13/23359-4

Made available in DSpace on 2021-06-25T11:09:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) No-tillage (NT) management has been one of the significant advances in Brazilian agriculture to enhance sustainability. However, weathered soils are acidic and may require amelioration to become more productive. Our objective was to determine the influence of surface application of different sources of soil acidity amendment under NT with different cover crops on soil carbon (C) and nitrogen (N) fractions, soil organic C stock, and soil physical attributes in a clayey Typic Hapludox in Botucatu, São Paulo State, Brazil. A randomized block design was repeated from 2007 to 2013 with main plots of cropping system with different treatments in off-season (forage crop, second crop, cover crop, and fallow) and split plots of soil acidity amendment (no amendment, limestone, and silicate) applied in 2006 and 2011. In 2013, soil was collected at 0–0.05, 0.05–0.1 and 0.1–0.2 m depths. Several soil C and N fractions and micro-porosity were greater (p < 0.05) with Urochloa forage than with other crops, but mainly only at 0–0.05 m depth. Mineralizable C and soil microbial biomass C were greater with application of limestone than without amendment. Application of soil acidity amendments had small, but positive effects on soil C and N fractions and physical properties. Our results suggest that greater crop biomass production in cropping systems under NT are beneficial to enhance soil C and N fractions and soil biological activity, particularly at 0–0.05 m soil depth. Therefore, cover cropping during the dry season in tropical Brazil is recommended to enhance soil condition, but improvements will depend on biomass production potential. Dom Bosco Catholic University, Tamandare Avenue, 6000 USDA-Agricultural Research Service, 3218 Williams Hall, NCSU Campus Box 7620 Sao Paulo State University (UNESP) College of Agricultural Sciences Department of Crop Science, Jose Barbosa de Barros Road, 1780, P.O.Box 237 Sao Paulo State University (UNESP) College of Agricultural Sciences Department of Crop Science, Jose Barbosa de Barros Road, 1780, P.O.Box 237

Background A field study with the same crop rotations was conducted to test the hypothesis that the soil Carbon fluxes and balances could vary according to the crop species and also mitigate carbon dioxide (CO2) emission. This study aimed to assess the CO2 emission from crop rotations according to C and N inputs from crop residue, the influences on soil organic carbon (SOC) and total soil nitrogen (TN) stocks, identifying the soybean production systems with positive C balance. Triticale (x Triticosecale) or sunflower (Helianthus annuus) are grown in the fall/winter; sunn hemp (Crotalaria juncea), forage sorghum (Sorghum bicolor), pearl millet (Pennisetum glaucum), or fallow are the spring treatments, and soybean as a main crop in summer. Results We found that high C inputs from crop residues modify the C dynamics in crop rotations by reducing the C output (CO2) and increasing C sequestration in the soil. In general, the higher SOC, C stocks, and TN in soil surface were due to higher C and N inputs from sunn hemp or forage sorghum crop residues in spring. These crops also produced lower accumulated CO2 emissions and, when rotating with triticale in the fall-winter season resulted in a positive C balance, making these soybean crop rotations more efficient. Conclusion Our study suggests the ideal crop species choice in a rotation can mitigate the CO2 emissions by increasing C and N input from crop residues and consequently SOC and C stocks. In particular, crop rotation comprises an important tool to achieve a positive C balance, mitigate CO2 emissions and provide an additional ecosystem service to soybean cultivation option.

Some crop species could be used inside a cropping system as part of a strategy to increase soil P availability due to their capacity to recycle P and shift the equilibrium between soil P fractions to benefit the main crop. The release of P by crop residue decomposition, and mobilization and uptake of otherwise recalcitrant P are important mechanisms capable of increasing P availability and crop yields.

Made available in DSpace on 2018-12-11T17:35:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-09-08 There is evidence that glyphosate application in soybean tolerant to herbicides could interfere in the manganese (Mn) nutrition of the crop, but there is no information on this effect in cotton plants. This study aimed at assessing manganese accumulation and distribution in cotton as affected by glyphosate application. The experiment was conducted in nutrient solution with four Mn concentrations and two cotton cultivars: conventional NuOpal and NuOpal tolerant to glyphosate (RR). Glyphosate was applied or not to the tolerant cultivar. The inclusion of the glyphosate resistance gene in cotton and herbicide, application increased shikimic acid (ShA) concentration in the plants. Glyphosate application decreased cotton leaf area and the dry matter production of the plant structures. The adverse effects of glyphosate were not overcome with higher Mn rates in the solution. Department of Crop Science College of Agricultural Sciences São Paulo State University (UNESP) Department of Crop Science College of Agricultural Sciences São Paulo State University (UNESP)

Made available in DSpace on 2018-12-11T17:34:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-08-06 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) It is convenient to store gas samples containing e.g. carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), in polypropylene syringes before chromatographic analysis. However, there is no study of the integrity of these samples or of what storage condition may be critical. To investigate we filled polypropylene syringes with two standard mixtures of CO2, CH4, and N2O, and stored them at ~2 °C and ~25 °C, and analyzed the contents using gas chromatography. Our results suggest that the storage of gases on the syringe at room temperature is not viable due the CO2 storage integrity when in low concentration. However, the quantitative integrity of samples is maintained when the syringe is kept refrigerated up to 19 h, period limited by CO2 and CH4, taking into account the three gases CO2, CH4, and N2O. College of Agricultural Sciences São Paulo State University (UNESP) College of Agricultural Sciences São Paulo State University (UNESP) FAPESP: 11/15361-3

Made available in DSpace on 2018-12-11T17:01:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-12-01 The development of smartphones, specifically their cameras, and imaging technologies has enabled their use as sensors/measurement tools. Here we aimed to evaluate the applicability of a fast and noninvasive method for the estimation of total chlorophyll (Chl), Chl a, Chl b, and carotenoids (Car) content of soybean plants using a smartphone camera. Single leaf disc images were obtained using a smartphone camera. Subsequently, for the same leaf discs, a Chl meter was used to obtain the relative index of Chl and the photosynthetic pigments were then determined using a classic method. The RGB, HSB and CIELab color models were extracted from the smartphone images and correlated to Chl values obtained using a Chl meter and by a standard laboratory protocol. The smartphone camera was sensitive enough to capture successfully a broad range of Chl and Car contents seen in soybean leaves. Although there was a variation between color models, some of the proposed regressions (e.g., the S and b index from HSB and Lab color models and NRI [RGB model]) were very close to the Chl meter values. Based on our findings, smartphones can be used for rapid and accurate estimation of soybean and Car contents in soybean leaves. Department of Crop Science Lageado Experimental Farm Sao Paulo State University (UNESP) College of Agricultural Science, José Barbosa de Barros Road 1780 Department of Soil and Environmental Resources Lageado Experimental Farm Sao Paulo State University (UNESP) College of Agricultural Science, José Barbosa de Barros Road 1780 Department of Crop Science Lageado Experimental Farm Sao Paulo State University (UNESP) College of Agricultural Science, José Barbosa de Barros Road 1780 Department of Soil and Environmental Resources Lageado Experimental Farm Sao Paulo State University (UNESP) College of Agricultural Science, José Barbosa de Barros Road 1780

Made available in DSpace on 2018-12-11T17:15:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01. Added 1 bitstream(s) on 2021-07-15T15:03:27Z : No. of bitstreams: 1 S0103-90162018000100018.pdf: 1590909 bytes, checksum: 4961ea23e5ee762b81c5445883bd8a10 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) In addition to improving sustainability in cropping systems, the use of a spring and winter crop rotation system may be a viable option for mitigating soil CO2 emissions (ECO2). This study aimed to determine short-term ECO2 as affected by crop rotations and soil management over one soybean cycle in two no-till experiments, and to assess the soybean yields with the lowest ECO2. Two experiments were carried out in fall-winter as follows: i) triticale and sunflower were grown in Typic Rhodudalf (TR), and ii) ruzigrass, grain sorghum, and ruzigrass + grain sorghum were grown in Rhodic Hapludox (RH). In the spring, pearl millet, sunn hemp, and forage sorghum were grown in both experiments. In addition, in TR a fallow treatment was also applied in the spring. Soybean was grown every year in the summer, and ECO2 were recorded during the growing period. The average ECO2 was 0.58 and 0.84 g m2 h−1 with accumulated ECO2 of 5,268 and 7,813 kg ha–1 C-CO2 in TR and RH, respectively. Sunn hemp, when compared to pearl millet, resulted in lower ECO2 by up to 12 % and an increase in soybean yield of 9% in TR. In RH, under the winter crop Ruzigrazz+Sorghum, ECO2 were lower by 17%, although with the same soybean yield. Soil moisture and N content of crop residues are the main drivers of ECO2 and soil clay content seems to play an important role in ECO2 that is worthy of further studies. In conclusion, sunn hemp in crop rotation may be utilized to mitigate ECO2 and improve soybean yield. São Paulo State University (UNESP) College of Agricultural Sciences Dept. Crop Science, R. José Barbosa de Barros, 1780 São Paulo State University FCAV – Exact Science Dept, Via de Acesso Prof. Paulo Donato Castellane, s/n São Paulo State University (UNESP) College of Agricultural Sciences Dept. Crop Science, R. José Barbosa de Barros, 1780 São Paulo State University FCAV – Exact Science Dept, Via de Acesso Prof. Paulo Donato Castellane, s/n FAPESP: 2009/16060-7 FAPESP: 2011/15361-3

Made available in DSpace on 2018-12-11T17:26:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The addition of urban and industrial waste products to agriculture not only provides them with an adequate environmental destination but also increases the nutrient content and negative charges in the soil, especially in naturally acidic tropical soils with high phosphorus-fixing capacity, just as liming does in relation to the dependent charges of pH. Both cases make it possible to favor the availability of phosphate fertilization. The aim of this study was to assess the interactions between application of composted sewage sludge (SSS) and soluble phosphorus (P) in combination with different rates of limestone (LS) and steel slag (SS) on the characteristics of dwarf castor bean and soil chemical properties. The experiment was conducted in a greenhouse in Botucatu, SP, Brazil. The Oxisol soil used was incubated with the combinations— based on chemical analyses of the soil, the waste product and slag, considering the needs of castor bean—in the 45 days prior to sowing, undertaking analysis of castor bean growth and dry-matter weight after physiological maturity, the time at which soil analysis was performed. SSS as an amendment of soil acidity provided better results in the properties of soil acidity, sum of bases (SB), cation exchange capacity (CEC), and base saturation (BS%). The combinations of the amendments were similar in regard to the increase of P availability in the soil. Although SSS alone resulted in an increase in organic matter (OM), nitrogen (N), magnesium (Mg), potassium (K), boron (B), cupper (Cu), zinc (Zn), and iron (Fe) contents in the soil, the low P content in the waste product extended the castor bean cycle, requiring P supplementation in combination. College of Agricultural Sciences São Paulo State University (UNESP) College of Agricultural Sciences São Paulo State University (UNESP) FAPESP: 11/16330-4

Liming is indispensable in acid soils for amending acidity; however, the technique may alter the cation balance in soil and, consequently, may limit the availability and uptake of nutrients. We aimed to evaluate different molar ratios between calcium (Ca) and magnesium (Mg) on the availability of soil nutrients and their influence on the productive properties of sunflower and seed quality. The experiment was carried out in a greenhouse under two types of contrasting soils and six molar combinations of CaCO3and MgCO3 in amendment of soil acidity to raise base saturation to 70%. After incubation, soil analysis was undertaken to verify the ratios obtained and nutrient availability. Morphological and production variables were analyzed at the end of the experiment, as well as accumulation of nutrients in the achenes and their physiological quality. In spite of equal base saturation between the types of soil, there were differences in the available contents of these cations. The increase in the Ca contents limi...

Treated and reused industrial residues and urban waste are depicted as potential alternative sources for agricultural use. In this context, the objective of this study was to determine the chemical element concentrations in organic residues from the Medium-High Uruguay Region of the Rio Grande do Sul, using energy dispersive x-ray fluorescence spectrometry (EDXRF). The organic compounds analyzed were meat agroindustry sludge, organic composites from agribusiness meat, and organic compounds from urban waste (particle sizes: >4.75 mm, 2.00 mm, and

Made available in DSpace on 2018-11-26T17:24:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-04-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The introduction of cover crops in agricultural systems under no-till is important in soil structuring and remediation. However, there is a lack of studies exploring the effects of cover crops compared with other soil compaction control tools, such as chiseling, in the long term, mainly under tropical climates. This study aimed to evaluate soil physical properties by cover crops and chiseling in a compacted soil, as well as its effects on soybean yields. The experiment was conducted in Botucatu, Brazil, under no-till. Three crops were grown per year. Soybean [Glycine max (L.) Merrill] was cropped as summer crop in rotation with triticale (X Triticosecale Wittmack) or sunflower [Helianthus annuus (L.)] as fall/winter crop. In spring, three different cover crops were grown, pearl millet [Pennisetum glaucum (L.) R. Brown], forage sorghum [Sorghum bicolor (L.) Moench] and sunn hemp [Crotalaria juncea (L.)], compared to a fallow treatment, which was chiseled in 2003, 2009 and 2013 only, always in October and down to 0.60 m depth. The first chiseling increased soil macroporosity and soybean yields in the immediate cropping season (2003/2004). However, these benefits were short-lived and in two years the use of cover crops resulted in higher yields. In the long-term, cover crops improve soil structure, with equal or better results than those obtained by occasional chiseling, as an increase in soil macroporosity by sunn hemp up to 0.20 m depth and a decrease in soil bulk density by sunn hemp and pearl millet in the 0.40-0.60 m layer. Among the cover crops, sunn hemp is particularly interesting, because it increases macroporosity in clay soils otherwise with limited aeration and increases the soybean yield. (C) 2017 Published by Elsevier B.V. Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Jose Barbosa Barros St 1780, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Coll Agr Sci, Dept Crop Sci, Jose Barbosa Barros St 1780, BR-18610307 Botucatu, SP, Brazil

Soil that has a high degree of weathering, with more inorganic P bound to Fe and Al oxides, has less P availability to plants. Thus, the critical element of a plant refers to the level below which the growth rate and plant production decreases, demonstrating the need for supplementary fertilization. Accordingly, an experiment was conducted in a greenhouse at Embrapa Algodão with the objective of evaluating the response of castor plants to five doses of P in four types of soil with different adsorption characteristics and critical levels of foliar P. The experimental design was completely randomized in a 4 x 5 factorial design, four types of soil and 5 levels of P with four replications. For TCo, there was an increase in height growth, with dose of 229.6 mg dm-3 responsible for maximum plant height (74.3 cm). The largest diameter stem (17.58 mm) was observed in CXve with an application of 229.6 mg dm-3 of P; a decrease was seen when using higher doses. The increase in leaf area was smaller in RY (4724.8 cm2), where it was obtained with a dose of 280.2 mg dm-3. In general, critical levels of P in the plant shoots did not vary much between the soils. The critical level of P in castor bean shoot dry mass was higher (4.61 g kg-1) in TCo, this result being directly related to the low clay content of the soil.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:28:37Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:48:13Z : No. of bitstreams: 1 2-s2.0-84878343123.pdf: 787794 bytes, checksum: 431ea18f8ac32fecd036c0f442d041b8 (MD5) Made available in DSpace on 2014-05-27T11:28:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-01 The aim of this work was to generate mathematical models capable of identifying photosynthetic pigments and soluble proteins from the leaves of Jatropha curcas using the relationship between classical readings performed by spectrophotometry and the chlorophyll meter, ClorofiLOG ® 1030. The work was conducted at Embrapa Cotton, in the city of Campina Grande, state of Paraíba, Brazil. For indirect analysis, portable equipment was used to read leaf discs at different stages of development. The chlorophyll in these discs was then determined using a classical method, while the Bradford method was used to determine soluble proteins. The data were subjected to analysis of variance and regression analyses, in which the readings obtained using the portable chlorophyll meter were the dependent variables and the photosynthetic pigments and soluble protein determined by the classical method the independents variables. The results indicated that with the exception of chlorophyll b and soluble protein, the mathematical models obtained with the portable chlorophyll ClorofiLOG ® 1030 can be used to estimate the concentration of photosynthetic pigments with high precision, thus saving time and the chemical reagents required for conventional procedures. Programa de Pós Graduação em Agricultura Faculdade de Ciências Agronômicas FCA/UNESP, Botucatu SP Empresa Brasileira de Pesquisa Agropecuária EMBRAPA Centro Nacional de Pesquisa de Algodão, Centenário, Campina Grande, PB Programa de Pós Graduação em Agricultura Faculdade de Ciências Agronômicas FCA/UNESP, Botucatu SP

O objetivo do presente trabalho foi gerar modelos matemáticos capazes de reportar os pigmentos fotossintéticos e proteína solúvel nas folhas de Jatropha curcas por meio da relação entre leituras realizadas por espectrofotometria clássica e por clorofilômetro, ClorofiLOG® 1030. O trabalho foi realizado na Embrapa Algodão, na cidade de Campina Grande (PB). Para a análise indireta, foi usado o equipamento portátil para leituras em discos foliares com diferentes estádios de desenvolvimento. A clorofila nestes discos foi então determinada usando o método clássico, enquanto que para a determinação da proteína solúvel utilizou-se a metodologia de Bradford. Os dados foram submetidos a análise de variância e de regressão em que as leituras obtidas com o medidor portátil de clorofila foram as variáveis dependentes e os pigmentos fotossintéticos e de proteínas solúveis, determinadas pelo método clássico foram as variáveis independentes. Os resultados indicaram que, com exceção da clorofila b, e proteína solúvel, os modelos matemáticos obtidos por meio do clorofilômetro portátil ClorofiLOG® 1030 podem ser utilizados para estimar a concentração dos pigmentos fotossintéticos com alta precisão, poupando tempo e reagentes químicos normalmente utilizados em procedimentos convencionais.O objetivo do presente trabalho foi gerar modelos matemáticos capazes de reportar os pigmentos fotossintéticos e proteína solúvel nas folhas de Jatropha curcas por meio da relação entre leituras realizadas por espectrofotometria clássica e por clorofilômetro, ClorofiLOG® 1030. O trabalho foi realizado na Embrapa Algodão, na cidade de Campina Grande (PB). Para a análise indireta, foi usado o equipamento portátil para leituras em discos foliares com diferentes estádios de desenvolvimento. A clorofila nestes discos foi então determinada usando o método clássico, enquanto que para a determinação da proteína solúvel utilizou-se a metodologia de Bradford. Os dados foram submetidos a análise de variância e de regressão em que as leituras obtidas com o medidor portátil de clorofila foram as variáveis dependentes e os pigmentos fotossintéticos e de proteínas solúveis, determinadas pelo método clássico foram as variáveis independentes. Os resultados indicaram que, com exceção da clorofila b, e proteína solúvel, os modelos matemáticos obtidos por meio do clorofilômetro portátil ClorofiLOG® 1030 podem ser utilizados para estimar a concentração dos pigmentos fotossintéticos com alta precisão, poupando tempo e reagentes químicos normalmente utilizados em procedimentos convencionais.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:26:23Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:31:34Z : No. of bitstreams: 1 2-s2.0-84865652567.pdf: 113359 bytes, checksum: fa1e389e55c9fbd182c1d2124cff318f (MD5) Made available in DSpace on 2014-05-27T11:26:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-01 In addition to the evaluations among genotypes, the use of multivariate techniques enables to restrict errors, mainly concerning genetic diversity, and therefore to predict combinations with greater heterotic effect, and the greater possibility of recovery of superior genotypes. The objective of this study was to evaluate the genetic divergence between 18 soybean cultivars based on six morphological characteristics. Path analysis was performed to verify the contribution of direct and indirect characters on grain yield. The Mahalanobis distance has founded techniques of both Tocher Method and dendrogram by Single Linkage. Five different groups were formed: with nine genotypes considered similar among them; while the cultivars CEP 59, Netuno and Urano formed groups isolated by the two grouping methods. The path analysis showed that the indirect characters had little influence on grain yield, with significant direct relationship with mass of 100 grain, and cultivars Tertulha and CEP 53 standing out with grain yields above 3.7 t.ha-1. Faculdade de Ciências Agronômicas Universidade Estadual Paulista (UNESP) Campus Botucatu, Fazenda Experimental Lageado, Caixa Postal 237, Rua José Barbosa de Barros, 1780, 18610-307, Botucatu, São Paulo Centro Nacional de Pesquisa do Algodão, Rua Oswaldo Cruz, 1143, Caixa Postal 174-Bairro Centenario, 58428-095, Campina Grande, Paraíba Departamento de Agronomia da Universidade Federal de Santa Maria Campus de Frederico Westphalen UFSM/CESNORS, Linha 7 de Setembro, s/n, Br 386, Km 80, 98400-000, Frederico Westphalen, Rio Grande do Sul Agronomia. Universidade Federal de Santa Maria Campus de Frederico Westphalen UFSM/CESNORS, Linha 7 de Setembro, s/n, Br 386, Km 80, 98400-000, Frederico Westphalen, Rio Grande do Sul Faculdade de Ciências Agronômicas Universidade Estadual Paulista (UNESP) Campus Botucatu, Fazenda Experimental Lageado, Caixa Postal 237, Rua José Barbosa de Barros, 1780, 18610-307, Botucatu, São Paulo

Objetivou-se, com o presente trabalho, relacionar pigmentos fotossintéticos extraídos de modo clássico em laboratório com leituras obtidas pelo clorofilômetro portátil ClorofiLOG 1030, em folhas de gergelim, por meio de modelos matemáticos. O trabalho foi realizado em dezembro de 2010, na Embrapa Algodão, de onde foram retirados discos foliares de gergelim para serem mensurados os índices de clorofila por meio do clorofilômetro portátil. Os discos foliares foram submetidos à extração dos pigmentos fotossintéticos, utilizando-se 5 mL de dimetilsulfóxido (DMSO) e mantidos em banho-maria a 70 ºC, durante 30 min; depois foram retirados 3 mL de alíquota para a leitura em espectrofotômetro nos comprimentos de onda de 470, 646 e 663 nm. Com base nos resultados analíticos modelos matemáticos foram ajustados utilizando-se o índice de clorofila na predição dos teores de clorofila a, b e total e dos carotenóides e suas relações. Concluiu-se que o medidor portátil de clorofila ClorofiLOG 1030 pode ser utilizado na estimativa da concentração dos pigmentos fotossintéticos em folhas de gergelim com alta precisão, além de proporcionar economia de recursos e tempo. The study aimed to relate the photosynthetic pigments, which were extracted in a laboratory and the readings were obtained by the portable chlorophyll meter ClorofiLOG 1030, by using mathematical models in sesame leaves. This work was conducted in December 2010, at Embrapa Cotton, where feaf discs were removed to measure chlorophyll indexes through the portable chlorophyll meter. The same leaf discs were subjected to extraction of photosynthetic pigments, by using 5 mL dimethyl sulfoxide (DMSO), and were kept in a water bath at 70 ºC for 30 min. Afterwards, an aliquot of 3 mL was removed to be read in a spectrophotometer at wavelengths of 470, 646 and 663 nm. Based on analytical results, mathematical models were adjusted by using the chlorophyll index to predict the levels of chlorophyll a, b, and total, and of carotenoids and their relationships. The study concluded that the portable chlorophyll meter ClorofiLOG 1030 can be used to estimate the concentration of photosynthetic pigments in sesame leaves with high precision, besides saving resources and time.

Made available in DSpace on 2015-08-26T19:22:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-06-01. Added 1 bitstream(s) on 2015-08-31T13:04:10Z : No. of bitstreams: 1 S0006-87052015000200156.pdf: 1188334 bytes, checksum: 7fe1b9a901bbae55a968abe236c8c829 (MD5) Two experiments with 25 maize commercial hybrids were carried out in a direct sowing system in Southern Brazil in the harvests of 2009/2010 and 2010/2011. Quantitative descriptors were used with the objective of determining the genetic divergence and the relative contributions of traits among hybrids for extraction of inbred lines. This study was carried out in Oxisol soil using a randomized block design with four replicates. Data were subjected to combined analysis of variance, and based on the multivariate analyses, Tocher and average linkage (UPGMA) cluster analyses, based on generalized distance of Mahalanobis, to quantify divergence in addition to Singh criterion to validate trait with the most contribution. The multivariate methods were consistent with each other, and the weight of 100 grains was the trait that contributed most to the divergence and had similar behavior in grain yield between hybrids in both years. Furthermore, this descriptor representing significant genetic variability for crossings and lines extraction to hybridization between BM 3061, ATL 200 and P 30B39 Y. Universidade Estadual Paulista Faculdade de Ciências Agronômicas Departamento de Fitotecnia UNESP FCA Departamento de Ciência do Solo Universidade Federal de Santa Maria Universidade Estadual Paulista Faculdade de Ciências Agronômicas Departamento de Fitotecnia UNESP FCA Departamento de Ciência do Solo

O flamboyant ( Delonix regia ) e reconhecido por sua exuberância na floracao. Apresenta sementes com grande variacao na viabilidade, em funcao da impermeabilidade tegumentar, necessitando de processos para superacao da dormencia. Neste sentido, objetivou-se com este trabalho, avaliar metodos para quebra da dormencia das sementes em casa de vegetacao. As sementes foram submetidas a diferentes tratamentos para superar a restricao tegumentar: escarificacao mecânica na parte ventral; choque termico com imersao das sementes em agua a 80 oC por 10 min e imersao das sementes em acido sulfurico, tendo como controle a semeadura sem intervencao. Observou-se que a escarificacao mecânica proporcionou os melhores resultados para quebra de dormencia das sementes.

Made available in DSpace on 2021-07-14T10:25:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-11. Added 1 bitstream(s) on 2021-07-14T11:29:41Z : No. of bitstreams: 1 S0103-84782012001100008.pdf: 93370 bytes, checksum: d3efd7b13045d50a482a528e72d73d73 (MD5) Objetivou-se com este estudo avaliar, por meio de caracteres quantitativos, a dissimilaridade genética entre cultivares de girassol em diferentes localidades, além da concordância entre os métodos, visando à extração de linhagens para possíveis cruzamentos. Foram cultivados oito híbridos de girassol em duas localidades no noroeste do Rio Grande do Sul, com solo predominantemente do tipo Latossolo Vermelho distrófico. Foram utilizados métodos multivariados para determinar a divergência genética, utilizando a distância generalizada de Mahalanobis. Apesar dos rendimentos distintos entre locais e cultivares, os métodos de agrupamento tiveram concordância entre si. Para obtenção de populações segregantes, a cultivar 'Olisun 5', independente da localidade, demonstrou-se com maior potencial de hibridação, tendo as maiores contribuições por meio do número de aquênios por capítulo e altura de inserção do capítulo. The aim of this study to evaluate by means of quantitative traits, the genetic dissimilarity among sunflower cultivars in different locations, in addition to the agreement between the methods in order to extract lines for future crosses. There were eight sunflower hybrids grown in two locations in northwestern Rio Grande do Sul, mainly with soil type Oxisol. Multivariate methods were used to determine the genetic diversity, using the Mahalanobis distance. Although the different yield between locations and cultivars, methods of grouping agreed among them selves. To obtain segregating populations, regardless of location, the cultivate 'Olisun 5', demonstrated greater potential for hybridization, with major contributions through number of achenes per chapter and height of the insertion section. Universidade Estadual Paulista, Departamento de Produção Vegetal Universidade Federal de Santa Maria, Centro de Educação Superior Norte do Rio Grande do Sul (CESNORS) Universidade Estadual Paulista, Departamento de Produção Vegetal

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:44:12Z No. of bitstreams: 1 S1807-86212012000300013.pdf: 628010 bytes, checksum: 76c5ac47d1d5c9bc725d6c26055f6e41 (MD5) Made available in DSpace on 2013-08-22T18:44:12Z (GMT). No. of bitstreams: 1 S1807-86212012000300013.pdf: 628010 bytes, checksum: 76c5ac47d1d5c9bc725d6c26055f6e41 (MD5) Previous issue date: 2012-09-01 Made available in DSpace on 2013-09-30T17:48:15Z (GMT). No. of bitstreams: 2 S1807-86212012000300013.pdf: 628010 bytes, checksum: 76c5ac47d1d5c9bc725d6c26055f6e41 (MD5) S1807-86212012000300013.pdf.txt: 24541 bytes, checksum: c40d85e8079cbb01cdd4874346575b4e (MD5) Previous issue date: 2012-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:21:21Z No. of bitstreams: 2 S1807-86212012000300013.pdf: 628010 bytes, checksum: 76c5ac47d1d5c9bc725d6c26055f6e41 (MD5) S1807-86212012000300013.pdf.txt: 24541 bytes, checksum: c40d85e8079cbb01cdd4874346575b4e (MD5) Made available in DSpace on 2014-05-20T13:21:21Z (GMT). No. of bitstreams: 2 S1807-86212012000300013.pdf: 628010 bytes, checksum: 76c5ac47d1d5c9bc725d6c26055f6e41 (MD5) S1807-86212012000300013.pdf.txt: 24541 bytes, checksum: c40d85e8079cbb01cdd4874346575b4e (MD5) Previous issue date: 2012-09-01 Objetivou-se com o presente trabalho, estabelecer a relação entre os pigmentos fotossintéticos extraídos em DMSO e as leituras obtidas no clorofilômetro portátil ClorofiLOG® 1030, gerando modelos matemáticos capazes de predizer os teores de clorofila e de carotenóides em folhas de mamoneira. O trabalho foi conduzido na Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Algodão, situada em Campina Grande, Estado da Paraíba, em outubro de 2010. Para a análise indireta, foi utilizado um equipamento portátil, sendo realizada a leitura em discos foliares com diferentes tonalidades de verde, sendo feita, nesses mesmos discos, a determinação da clorofila pelo método clássico. Para a extração da clorofila, utilizaram-se 5 mL de dimetilsulfóxido (DMSO), a qual foi mantida em banho-maria a 70ºC, por 30 minutos, e retirou-se 3 mL da alíquota para leitura em espectrofotômetro nos comprimentos de onda de 470, 646 e 663 nm. Os dados foram submetidos à análise da variância e regressão polinomial. A leitura obtida no clorofilômetro portátil foi a variável dependente, e os pigmentos fotossintéticos determinados pelo método clássico foi a variável independente. Os resultados indicaram que o clorofilômetro portátil ClorofiLOG® 1030, associado a modelos matemáticos, permitiu estimar a concentração dos pigmentos fotossintéticos, exceto a clorofila b, com alta precisão, com economia de tempo e com reagentes normalmente utilizados nos procedimentos convencionais. The aim of the present work was to determine the relationship between photosynthetic pigments extracted in dimethyl sulfoxide (DMSO) and readings obtained by the portable chlorophyll meter, ClorofiLOG® 1030, to generate mathematical models that are able to report the contents of chlorophyll and carotenoids in the leaves of the castor oil plant. This work was conducted at Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Cotton, located in the city of Campina Grande, state of Paraíba, Brazil, in October 2010. For the indirect analysis, portable equipment was used to read leaf discs of different shades of green. The chlorophyll in these discs was then determined using a classical method: 5 mL of DMSO was added, the samples were incubated in a water bath at 70ºC for 30 minutes, and a 3 mL aliquot was removed for spectrophotometric measurements at 470, 646 and 663 nm. The data were subjected to analysis of variance and regression analyses in which the readings obtained using the portable chlorophyll meter were the dependent variable and the photosynthetic pigments that were determined by the classical method were the independent variable. The results indicated that, with the exception of chlorophyll b, the ClorofiLOG® 1030 portable chlorophyll meter estimated the concentration of photosynthetic pigments with high precision, thus saving time and the chemical reagents that are typically used in conventional procedures. Universidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências Agronômicas Departamento de Fitotecnia Empresa Brasileira de Pesquisa Agropecuária Centro Nacional de Pesquisa de Algodão Universidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências Agronômicas Departamento de Fitotecnia

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:26:52Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:47:43Z : No. of bitstreams: 1 2-s2.0-84871599133.pdf: 369191 bytes, checksum: 0e850018d7fb71d0a7ba36902091caeb (MD5) Made available in DSpace on 2014-05-27T11:26:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-01 Secondary compounds produced by plants are considered an alternative method of weed suppression but can cause negative effects on crops in succession, especially in a no-tillage system, due to the degradation of crop residues with allelopathic potential. The objective of this work was to analyze the influence of foliar aqueous extracts of Brassica napus on the germination and initial development of seedlings of Phaseolus vulgaris. The extract was prepared as a stock 10 % weight/volume solution, and diluted into treatments of relative concentrations of 100 % (i.e. 10 % w/v stock), 75 %, 50 %, 25 % and 0 % (untreated control consisting of distilled water), in a completely randomized design. The seeds of Phaseolus vulgaris were moistened with the differing concentrated extracts and kept in a germination chamber at 25 °C, with a photoperiod of 12 h for nine days. The variables evaluated were: percentage germinating, first count of germination and germination velocity index, as well the root and hypocotyl length, and fresh and dry mass of the seedlings. The aqueous leaf extracts of Brassica napus did not influence the germination of Phaseolus vulgaris seeds, but did induce the growth of abnormal seedlings by inhibition of secondary roots and reduced prominence of the primary root. Universidade Estadual Paulista Júlio de Mesquista FIlho, Rua José Barbosa de Barros, Lageado, CEP 18610-307, Botucatu-SP Universidade Federal de Santa Maria Centro de Educação Superior Norte Do Estado Do Rio Grande Do sul Campus de Frederico Westphalen, BR 386, Km 40, Linha Sete de Setembro, CEP 98400-000, Frederico Westphalen-RS Universidade Estadual Paulista Júlio de Mesquista FIlho, Rua José Barbosa de Barros, Lageado, CEP 18610-307, Botucatu-SP

Made available in DSpace on 2015-08-26T19:21:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-01. Added 1 bitstream(s) on 2015-08-31T13:04:13Z : No. of bitstreams: 1 S0103-84782015000300485.pdf: 463277 bytes, checksum: 427a12a8422d36cc869f030d7257ca8c (MD5) O presente trabalho objetivou estimar a divergência genética entre ecótipos de Urochloa brizantha com base na análise de descritores quantitativos, qualitativos e sua análise conjunta a fim de selecionar os promissores para liberação como cultivares desta espécie. Oito ecótipos (B1, B2, B3, B4, B5, B6, B8) e a cultivar 'Marandu' de U. brizantha foram implantados em piquetes, com 1000m2 cada, em duas repetições. Foram avaliados cinco descritores quantitativos e dez qualitativos no período seco e das águas. Os descritores quantitativos foram: área foliar, comprimento e largura das lâminas foliares, massa seca (MS) e proporção de lâmina foliar na MS. Os descritores qualitativos mensurados foram: resistência ao cisalhamento, volume de gás acumulado na fração rápida e lenta, proteína bruta, fibra em detergente neutro, fibra em detergente ácido, celulose, lignina em ácido sulfúrico, sílica e digestibilidade in vitro da matéria orgânica. Houve divergência genética entre os ecótipos de U. brizantha, especialmente em relação aos descritores quantitativos. Com base nos agrupamentos dos descritores quantitativos, qualitativos e sua análise conjunta, o agrupamento contendo de B1, B3 e B5 com 'Marandu' podem resultar em ecótipos promissores de U. brizantha This study aimed to estimate the genetic divergence between Urochloa brizantha ecotypes based on quantitative, qualitative descriptors and their joint analysis to select the promising to release as cultivars of this species. Eight ecotypes (B1, B2, B3, B4, B5, B6, B8) and cultivar 'Marandu' of U. brizantha were implanted into pickets with 1000m2 each, with two repetitions. Five quantitative descriptors were evaluated [leaf area (ALF), length and width of leaf blades (CLF and LLF, respectively), dry mass (MS), mass of dry matter (MMS) and proportion of leaf blade in MS (PLF)] in two forage samples, being a representative of rainfall, in February 2000, and another in the dry period, in August 2000. It was measured the qualitative descriptors: shear strength (RC), volume of accumulated gas in fast and slow fraction (A and B, respectively), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF ), cellulose (CEL), lignin in sulfuric acid (LIG), silica (SIL) and in vitro digestibility of organic matter (IVOMD). There was considerable genetic divergence in U. brizantha ecotypes, especially regarding to quantitative descriptors. Based on the groupings of quantitative, qualitative descriptors and their joint analysis, the grouping containing of B1, B3 and B5 with 'Marandu' can result in promising U. brizantha ecotypes Universidade Estadual de Mato Grosso do Sul Departamento de Fitotecnia Faculdade de Agronomia Embrapa Gado de Corte Universidade Federal da Grande Dourados Departamento de Produção e Melhoramento Vegetal Faculdade de Ciências Agrárias Universidade Estadual Paulista Júlio de Mesquita Filho Departamento de Produção e Melhoramento Vegetal Faculdade de Ciências Agronômicas