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The aim of this study was to evaluate two maize genotypes with contrasting drought-resistant phenotypic traits and to characterize how the plastic phenotypic traits contribute to yield potential under drought. The maize genotypes DKB 390 and BRS 1010 present contrasting yield traits in relation to drought and were treated with two water regimes: well-watered plant (WW, ??2 kPa) and water deficit (WD, ??100 kPa). In WD conditions, DKB 390 had a greater capacity to accumulate biomass in shoots than BRS 1010, indicating that shoot traits are important in increasing yield gain in the DKB 390 drought tolerant genotype and therefore, an important phenotypic trait for breeding for high yield in drought conditions. However, neither the total root dry mass nor its ratio to the shoot was related to increased yield. A large reduction in gas exchange and increased water use efficiency was observed in BRS 1010 compared to DKB 390. These traits are likely related to yield loss mainly due to decreased transpiration rate and stomatal conductance, which led to low photosynthetic rates and reduced growth. The root angle between genotypes was a constitutive trait and can be primarily responsible for the differences in yield. However, this trait in the DKB 390 genotype was affected by WD, as indicated by narrowing of the root angle. Our work describes the relationship between the narrow root growth angle in DKB 390 and its association with an increased capacity for water uptake in deeper regions, which may result in higher yield under drought. Regarding leaf anatomy we hypothesized that both osmotic adjustment and cell wall properties can influence anisotropic cell expansion under WD conditions and result in leaf tissue with higher yield potential in DKB 390. The high plasticity of vascular tissues and wide vessels could indicate a greater propensity for embolism and a slower response to WD, leading to yield loss in BRS 1010. The results of the phenotypic plasticity of maize genotypes show a negative relationship between high plasticity and yield potential and suggest that high plasticity can result in higher yield potential only when are present in phenotypic traits responsible for higher water uptake and drought tolerance. Made available in DSpace on 2020-04-15T01:01:03Z (GMT). No. of bitstreams: 1 Yieldrelated.pdf: 3074636 bytes, checksum: 44fe753aca3295a7cc37e95742ed8b3b (MD5) Previous issue date: 2020

This paper aimed to analyze farmers’ perception of climate change and adaptation strategies in Minas Gerais State, Brazil. The general features of agricultural establishments, social-economics information of farmers and their perception to climate change are examined, as well as the adaptive measures adopted on a survey conducted during the 83rdFarmer Week (UFV) held in 2012. Our results indicate that mostly survey respondents have knowledge about the discussions on climate change. Moreover, the main climatic issue is the precipitation change. Farmers have adapted themselves through changes in sowing or harvesting dates, use of irrigation or no-till farming. On the other hand, it was observed a low adaptive measures adoption, since only 24% of survey respondents have changed their farming practices to cope with the impacts of climate change. Thus low access to credit, information and technical guidance, among other obstacles, which compromise the adaptive capacity of farmers could explain these features., Este artigo teve por objetivos investigar a percepção de produtores rurais de Minas Gerais relativamente a mudanças climáticas e a adoção de estratégias adaptativas. Para a análise foram recolhidos dados por meio de um questionário semiestruturado, aplicado durante a 83ª Semana do Fazendeiro (UFV), que ocorreu em 2012. O questionário continha questões sobre as características gerais das propriedades agrícolas, informações socioeconómicas dos produtores e a sua percepção face às mudanças do clima e medidas adaptativas adotadas. Os resultados indicam que a maior parte dos produtores entrevistados têm conhecimento das discussões sobre mudanças no clima e que a percepção é mais elevada quando se trata de alterações nos padrões de precipitação. Os agricultores têm respondido a tais mudanças por meio de alterações nas datas de plantação e colheita, uso de irrigação ou plantação direta na palha. Todavia, a adoção de estratégias adaptativas é muito baixa, visto que apenas 24% dos agricultores têm alterado as suas práticas agrícolas para lidar com o impactos das mudanças climáticas. Isso pode ser explicado pelo baixo acesso ao crédito, informações e assistência técnica, entre outras dificuldades, que comprometem a capacidade adaptativa dos agricultores.

Made available in DSpace on 2018-11-28T04:46:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This experiment evaluated the effects of temperament on physiological, productive, and reproductive responses in Bos indicus beef cows. A total of 953 lactating, multiparous, non-pregnant Nelore cows (age = 99 +/- 2 mo; days post-partum = 51.4 +/- 0.3 d; BCS = 5.34 +/- 0.04; BW = 430 +/- 2 kg) were allocated into 8 groups of approximately 120 cows each. Groups were assigned to an estrus synchronization + timed-AI protocol at the beginning of the breeding season. Concurrently with AI, blood samples were collected, hair samples were clipped from the tail switch, and cow temperament was evaluated via chute score and exit velocity. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning cows with a score from 1 to 5 (1 = slowest; 5 = fastest cow). Temperament scores were calculated by averaging cow chute score and exit score, and used to define cow temperament ( 3 = excitable, n = 227; EXC). Cows not pregnant to AI were assigned to a second timed-AI protocol (n = 184 ADQ and 72 EXC) or exposed (n = 269 ADQ and 90 EXC) to bulls for 60 d. Pregnancy status was verified 30 d after each AI and 45 d after the breeding season via transrectal ultrasound. Cow age, BW, BCS, and d post-partum at the beginning of the breeding season were similar (P >= 0.27) between ADQ and EXC cows. At first timed-AI, EXC had greater (P < 0.01) serum cortisol but similar (P >= 0.87) serum haptoglobin and hair cortisol concentrations compared with ADQ cows (49.1 vs. 39.1 ng/mL of serum cortisol, SEM = 1.0). Pregnancy rate to first timed-AI tended (P = 0.09) to be less in EXC vs. ADQ cows (41.0 vs. 47.3%; SEM = 3.6), whereas no treatment differences were detected (P >= 0.23) for subsequent pregnancy outcomes. Calving rate was less (P = 0.04) in EXC vs. ADQ cows (68.3 vs. 74.8%; SEM = 2.2), which can be attributed to the greater (P = 0.05) pregnancy loss detected in EXC cows (9.9 vs. 5.9%; SEM = 1.4). Weaning rate tended (P = 0.09) to be less, whereas calf weaning BW and age were less (P = 0.05) in EXC vs. ADQ cows (63.9 vs. 69.4%, SEM = 2.4; 209 vs. 212 d, SEM = 1; 204 vs. 210 kg, SEM = 2). Hence, kg of calf weaned/cow exposed to breeding was reduced (P = 0.04) in EXC vs. ADQ cows (130 vs. 146 kg, SEM = 5). In summary, B. indicus cows with excitable temperament had reduced reproductive performance and overall productivity compared to cohorts with adequate temperament when exposed to timed-AI + natural breeding. Oregon State Univ, Eastern Oregon Agr Res Ctr, Burns, OR 97720 USA Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil Unisalesiano Auxilium, BR-16016500 Aracatuba, SP, Brazil Univ Sao Paulo, ESALQ, Dept Zootecnia, BR-13418900 Piracicaba, SP, Brazil UNESP Univ Estadual Paulista, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil UNESP Univ Estadual Paulista, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil FAPESP: 2014/14136-4 FAPESP: 2014/19485-7

Made available in DSpace on 2018-11-28T03:37:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The objective of this experiment was to compare hormonal, uterine, and conceptus factors associated with pregnancy establishment in Bos indicus beef cows supplemented or not with Ca salts of soybean oil (CSSO) for 21 d beginning after timed AI. One hundred lactating multiparous Nelore cows were allocated to 20 groups of 5 cows/group and timed inseminated on d 0 of the experiment. After AI, groups were randomly assigned to receive (as-fed basis) 100 g of protein-mineral mix + 100 g of ground corn per cow per day, in addition to 1) 100 g/cow daily of CSSO (n = 10) or 2) 100 g/cow daily of kaolin (CON; rumen-inert indigestible substance; n = 10). Groups were maintained in 4 Panicum maximum pastures (5 groups from the same treatment within each pasture) with ad libitum access to forage. Groups were segregated daily and individually offered treatments from d 0 to 21. Blood samples were collected and transrectal ultrasonography was performed to verify ovulation and corpus luteum (CL) volume immediately before AI (d 0) and on d 7 and 15. After ultrasonography on d 15, 60 cows (30 cows/treatment and 3 cows/group) diagnosed without the presence of a CL on d 0 but with a CL greater than 0.38 cm3 in volume on d 7 and 15 were assigned to conceptus collection via transcervical flushing with PBS followed by endometrial biopsy in the uterine horn ipsilateral to the CL. Additional blood samples were collected for wholeblood RNA extraction (d 20), and pregnancy status was verified by transrectal ultrasonography (d 30) in cows not assigned to conceptus collection. Cows receiving CSSO had greater (P = 0.30) for endometrial mRNA expression of prostaglandin E synthase and cyclooxygenase-2. In summary, post-AI CSSO supplementation to B. indicus beef cows increased plasma concentration of linoleic acid and enhanced pregnancy establishment factors, which included CL development and plasma P4 concentration, conceptus growth, and mRNA expression of interferon-tau as well as blood mRNA expression of interferon-stimulated genes. Unisalesiano Auxilium, BR-16016500 Aracatuba, SP, Brazil Oregon State Univ, Eastern Oregon Agr Res Ctr, Burns, OR 97720 USA Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil Univ Sao Paulo, ESALQ, Dept Zootecnia, BR-13418900 Piracicaba, SP, Brazil Univ British Columbia, Fac Land & Food Syst, Vancouver, BC V6T 1Z4, Canada Univ Estadual Paulista, UNESP, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil Univ Estadual Paulista, UNESP, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil FAPESP: 2014/14136-4

During dark‐induced senescence isovaleryl‐CoA dehydrogenase (IVDH) and D‐2‐hydroxyglutarate dehydrogenase (D‐2HGDH) act as alternate electron donors to the ubiquinol pool via the electron‐transfer flavoprotein/electron‐transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) pathway. However, the role of this pathway in response to other stresses still remains unclear. Here, we demonstrated that this alternative pathway is associated with tolerance to drought in Arabidopsis. In comparison with wild type (WT) and lines overexpressing D‐2GHDH, loss‐of‐function etfqo‐1, d2hgdh‐2 and ivdh‐1 mutants displayed compromised respiration rates and were more sensitive to drought. Our results demonstrated that an operational ETF/ETFQO pathway is associated with plants' ability to withstand drought and to recover growth once water becomes replete. Drought‐induced metabolic reprogramming resulted in an increase in tricarboxylic acid (TCA) cycle intermediates and total amino acid levels, as well as decreases in protein, starch and nitrate contents. The enhanced levels of the branched‐chain amino acids in loss‐of‐function mutants appear to be related to their increased utilization as substrates for the TCA cycle under water stress. Our results thus show that mitochondrial metabolism is highly active during drought stress responses and provide support for a role of alternative respiratory pathways within this response.

RESUMOObjetivou-se com este trabalho comparar o padrão de crescimento, mediante ajustes das respectivas curvas de crescimento por modelos não lineares, bem como estudar o desenvolvimento de cortes de carcaça em relação ao peso da carcaça em diferentes genótipos de frangos tipo caipira. Foram utilizados 840 pintos de um dia, machos, distribuídos em delineamento inteiramente ao acaso, dos seguintes genótipos da linhagem Redbro: Caboclo, Carijó, Colorpak, Gigante Negro, Pesadão Vermelho, Pescoço Pelado e Tricolor. As aves foram alojadas em 28 boxes, sendo 30 aves/boxe, em galpão de alvenaria com acesso a um piquete de 45m², com quatro repetições. O peso corporal individual dos frangos foi medido ao nascer, aos 14, 28, 42, 56, 70 e 84 dias de idade. Para a determinação das curvas de crescimento do peso corporal das aves, os dados coletados foram avaliados por meio dos modelos não lineares: Brody, Gompertz, Logístico, Richards e von Bertalanffy. Foi empregado o PROC NLIN do SAS, utilizando-se o método interativo de Gauss-Newton. Os critérios usados para escolha do modelo de melhor ajuste da curva de crescimento foram o coeficiente de determinação, o desvio padrão assintótico, o desvio médio absoluto dos resíduos e o índice assintótico. As análises para obtenção dos coeficientes alométricos foram realizadas por meio do PROC GLM do SAS para os genótipos Carijó, Colorpak, Pesadão Vermelho, Pescoço Pelado e Tricolor. Foram avaliados os pesos da carcaça, do peito, das coxas, das sobrecoxas, das pernas e das asas das aves abatidas aos 85 dias de idade. Apenas as equações propostas por Gompertz, von Bertalanffy e Logístico atingiram a convergência, e o modelo proposto por von Bertalanffy foi o mais adequado para descrever o crescimento dos genótipos de frangos caipiras. Todos os cortes avaliados apresentaram crescimento tardio em relação ao peso da carcaça em genótipos de frangos tipo caipira. ABSTRACTThe aim of this work was to compare the growth pattern, adjusting the growth curves by nonlinear models and studying the development of housing sections in relation to the weight of the chicken carcass in different genotypes of an alternative strain of broiler chickens. We used 840 one day old male chicks distributed in a completely randomized design, with the following genotype strains: Redbro: Caboclo, Carijó, Colorpak, Gigante Negro, Pesadão Vermelho, Pescoço Pelado and Tricolor. The birds were housed in 28 boxes, 30 birds / box in a masonry shed with access to a 45 square meter paddock, with four replications. Body weight was measured in chickens up to 84 days of age. To determine the growth curves of the body weight of birds, collected data were evaluated from the nonlinear models: Brody, Gompertz, Logistic, Richards and von Bertalanffy. Was used "proc nlin" of SAS, using the iterative method of Gauss-Newton. The criteria used to choose the best model for the growth curve were the coefficient of determination, the asymptotic standard deviation, the mean absolute deviation of the waste and the asymptotic index. The analysis to obtain the allometric coefficients were performed using the "proc glm" SAS for genotypes Carijó, Colorpak, Pesadão Vermelho, Pescoço Pelado and Tricolor. We assessed the weights of carcass, breast, thighs, drumsticks, legs and wings. Only the equations proposed by Gompertz, Logistic and von Bertalanfy reached convergence, and the model proposed by von Bertalanffy was the most appropriate. All sections were evaluated in relation to the late growth of carcass weight in alternative lines of broiler chickens.

Phosphorus is an important mineral for optimum growth and bone mineralization and is considered the third most expensive nutrient in diets for nonruminants. An experiment was conducted to evaluate the available phosphorus requirements (AP) for meat-type quail in the starter phase (1 to 21 days old). One-day-old, unsexed European quail (375) from the LF1 lineage were used for the study and were housed in pens. The experiment had a completely randomized design, with five treatments (0.13, 0.23, 0.33, 0.43 and 0.53% of AP), each of which included five replicates in 15 birds. Feed intake, weight gain, feed conversion ratio, and the tibial deposition of phosphorus, calcium, and ash were assessed. The AP levels influenced all studied variables. We calculated that levels of 0.381% AP or 0.12% AP megacalorie of metabolizable energy (% AP/Mcal ME) were best for bone quality related to high tibial ash deposition. El fósforo es un mineral importante por ser necesario para la óptima tasa de crecimiento y para la mineralización ósea, siendo considerado como el tercer nutriente más caro en los concentrados para no rumiantes. Fue conducido un experimento para evaluar las exigencias de fósforo disponible (Pd) para codornices de engorde en la fase inicial de cría (1 a 21 días de edad). Se utilizaron 375 codornices europeas, linaje LF1, no sexadas, instaladas en compartimientos. El delineamiento experimental utilizado fue enteramente al azar, siendo los tratamientos constituidos por cinco niveles de Pd (0,13; 0,23; 0,33; 0,43 y 0,53%) cada tratamiento contó con cinco repeticiones de 15 aves por repetición. Se evaluó el consumo de concentrado, la ganancia de peso, la conversión alimenticia y la deposición de fósforo, calcio y cenizas en las tibias. Se observó que los niveles de Pd estudiados influenciaron todas las variables analizadas. Fue calculado el nivel de 0,381% de Pd o 0,12% de Pd/Megacaloría de Energía Metabolizable para obtener la mejor calidad ósea, porque permite maximizar la deposición de cenizas en la tibia de las codornices de engorde.

Here, we provide an analysis to understand the evolution of cereal production and consumption of nitrogen (N) fertilizers in Brazil and to correlate N use efficiency (NUE), greenhouse gas (GHG) emissions and economic and environmental losses. Our results showed that the increased consumption of N fertilizers is associated with a large decrease in NUE in recent years. CO2eq emissions from N fertilization for cereal production were approximately 12 times higher in 2011 compared to 1970. The projected N fertilizer forecasts are 2.09 and 2.37 million ton for 2015 and 2023, respectively. An increase of 0.02% per year in the projected NUE was predicted for the same time period. In a hypothetical scenario, a 2.39% increase in cereal NUE would lead to USD 21 million savings in N fertilizer costs. Thus, increases in NUE rates would lead not only to agronomic and environmental benefits but also to economic improvement.

Este artigo teve por objetivos investigar a percepção de produtores rurais de Minas Gerais relativamente a mudanças climáticas e a adoção de estratégias adaptativas. Para a análise foram recolhidos dados por meio de um questionário semiestruturado, aplicado durante a 83ª Semana do Fazendeiro (UFV), que ocorreu em 2012. O questionário continha questões sobre as características gerais das propriedades agrícolas, informações socioeconómicas dos produtores e a sua percepção face às mudanças do clima e medidas adaptativas adotadas. Os resultados indicam que a maior parte dos produtores entrevistados têm conhecimento das discussões sobre mudanças no clima e que a percepção é mais elevada quando se trata de alterações nos padrões de precipitação. Os agricultores têm respondido a tais mudanças por meio de alterações nas datas de plantação e colheita, uso de irrigação ou plantação direta na palha. Todavia, a adoção de estratégias adaptativas é muito baixa, visto que apenas 24% dos agricultores têm alterado as suas práticas agrícolas para lidar com o impactos das mudanças climáticas. Isso pode ser explicado pelo baixo acesso ao crédito, informações e assistência técnica, entre outras dificuldades, que comprometem a capacidade adaptativa dos agricultores., Revista de Ciências Agrárias, vol. 37 n.º 4 (2014)

Resumo: O objetivo deste trabalho foi estimar herdabilidades, correlações genéticas e fenotípicas e tendências genéticas das características morfológicas e de tipo de caprinos da raça Saanen nascidos no Brasil de 1979 a 2009. Dados de 1243 caprinos, 197 machos e 1046 fêmeas, foram utilizados para estimar parâmetros genéticos e tendência das características: perímetro torácico, comprimento corporal, altura na cernelha, altura, largura e comprimento da garupa, bem como as principais características que definem o padrão racial e a aptidão do animal (paleta e linha superior, membros e pés, tipo leiteiro, capacidade de corpo, úbere, ligamento traseiro e dianteiro, textura do úbere, tetos e nota). Os componentes de variância foram estimados pelo método da máxima verossimilhança restrita em análise multicaracterística. A tendência genética foi obtida por meio da regressão dos valores genéticos médios por ano de nascimento. As estimativas de herdabilidade das características morfofuncionais variaram de 0,08 a 0,45, as correlações genéticas de -0,58 a 0,89 e fenotípicas de -0,11 a 0,87. A tendência foi de um leve declínio ao longo dos anos para a maior parte das características avaliadas, o que evidencia a existência de variabilidade genética aditiva entre os animais, mas demonstra que a seleção praticada tem sido pouco efetiva. [Genetic evaluation of Saanen goats born in Brazil from 1979 to 2009]. Abstract: The aim of this study was to estimate heritability, genetic and phenotypic correlations and genetic trends of morphological characteristics and type of Saanen goats born in Brazil from 1979 to 2009. Data from 1243 goats, 197 males and 1046 females were used to estimate genetic parameters and trends for the following traits: girth, body length, wither height, height, width and rump length, and the main traits that define the breed standard and ability of the animal (shoulder and topline, limbs and feet, dairy type, body capacity, mammary gland, linking front and rear, texture of the udder, teats and note). Variance components were estimated by Restricted Maximum Likelihood multi-trait analysis. Genetic trends were obtained by regression of mean breeding values by year of birth. The heritability estimates of morphological and functional traits ranged from 0.08 to 0.45, the genetic correlations from -0.58 to 0.89 and phenotypes from -0.11 to 0.87. The trend was a slight decline over the years for most traits, which shows the existence of additive genetic variability among animals, but it demonstrates that the selection practiced has been ineffective. Made available in DSpace on 2014-11-14T08:08:39Z (GMT). No. of bitstreams: 1 apAvaliacao.pdf: 355212 bytes, checksum: 08cffdb57442521a4c11b40e3c7275b7 (MD5) Previous issue date: 2014-11-13