Functional specialization of chloroplast vesiculation (CV) duplicated genes from soybean shows partial overlapping roles during stress-induced or natural senescence.

Soybean is a globally important legume crop which is highly sensitive to drought. The identification of genes of particular relevance for drought responses provides an important basis to improve tolerance to environmental stress. Chloroplast Vesiculation (CV) genes have been characterized in Arabidopsis and rice as proteins participating in a specific chloroplast-degradation vesicular pathway (CVV) during natural or stress-induced leaf senescence. Soybean genome contains two paralogous genes encoding highly similar CV proteins, CV1 and CV2. In this study, we found that expression of CV1 was differentially upregulated by drought stress in soybean contrasting genotypes exhibiting slow-wilting (tolerant) or fast-wilting (sensitive) phenotypes. CV1 reached higher induction levels in fast-wilting plants, suggesting a negative correlation between CV1 gene expression and drought tolerance. In contrast, autophagy (ATG8) and ATI-PS (ATI1) genes were induced to higher levels in slow-wilting plants, supporting a pro-survival role for these genes in soybean drought tolerance responses. The biological function of soybean CVs in chloroplast degradation was confirmed by analyzing the effect of conditional overexpression of CV2-FLAG fusions on the accumulation of specific chloroplast proteins. Functional specificity of CV1 and CV2 genes was assessed by analyzing their specific promoter activities in transgenic Arabidopsis expressing GUS reporter gene driven by CV1 or CV2 promoters. CV1 promoter responded primarily to abiotic stimuli (hyperosmolarity, salinity and oxidative stress), while the promoter of CV2 was predominantly active during natural senescence. Both promoters were highly responsive to auxin but only CV1 responded to other stress-related hormones, such as ABA, salicylic acid and methyl jasmonate. Moreover, the dark-induced expression of CV2, but not of CV1, was strongly inhibited by cytokinin, indicating similarities in the regulation of CV2 to the reported expression of Arabidopsis and rice CV genes. Finally, we report the expression of both CV1 and CV2 genes in roots of soybean and transgenic Arabidopsis, suggesting a role for the encoded proteins in root plastids. Together, the results indicate differential roles for CV1 and CV2 in development and in responses to environmental stress, and point to CV1 as a potential target for gene editing to improve crop performance under stress without compromising natural development.

RESPUESTAS TEMPRANAS EN SIMPLASTO DE TALLO ASOCIADAS A LA RUTA DEL ÁCIDO SALICÍLICO EN LA INTERACCIÓN CLAVEL (Dianthus caryophyllus, caryophyllaceae)- Fod (Fusarium oxysporum f. sp. dianthi) / Early responses at symplastic stem level associated with the salicylic acid pathway in the interaction carnation (Dianthus caryophyllus, caryophyllaceae)- Fod (Fusarium oxysporum f. Sp. dianthi)

RESUMEN El marchitamiento vascular causado por Fusarium oxysporum f. sp. dianthi (Fod) es la enfermedad que más afecta el cultivo de clavel. Comprender la naturaleza de la interacción entre la planta y el patógeno permitirá el futuro desarrollo de nuevas alternativas de control de la enfermedad. Es por ello que se busca tener evidencia experimental que permita entender el papel de la ruta de señalización del ácido salicílico (SA) y enzimas asociadas con la resistencia de la planta como son fenilalanina amonio liasa (PAL), polifenoloxidasa (PFO), guayacol peroxidasa (GPX) y fosfolipasa D (PLD), a nivel del simplasto del tallo durante la interacción con él patógeno. Se estableció un ensayo in vivo utilizando dos variedades de clavel con diferentes niveles de resistencia a la enfermedad y se determinaron en simplasto de tallo los niveles de SA, MeSA (salicilato de metilo) y las enzimas objeto de estudio. Se presentó inducción de las enzimas estudiadas, evidenciando en el caso de la enzima GPX un aumento a nivel transcripcional. Así mismo, se presentó un incremento de MeSA en los 1 y 14 dpi, mientras que SA se acumuló en tiempos tardíos. La correlación de Pearson determinó que a este nivel existe una acumulación de la hormona MeSA al 1 dpi con los niveles de las enzimas GPX y PLD. Se propone que la respuesta en este órgano de clavel puede estar activada por la ruta de señalización que involucra SA, afectando el metabolismo secundario y la regulación de especies reactivas de oxígeno.

ABSTRACT The vascular wilting caused by the Fusarium oxysporum f. sp. dianthi (Fod) is the most important disease affecting carnation crops. Understanding the nature of the interaction between the plant and the pathogen will allow the development of new alternatives for disease control. That is why on this study, we want to know the role of the salicylic acid's (SA) signaling pathway and of some enzymes associated to the plant's resistance such as phenylalanine amino lyase (PAL), polyphenol oxidase (PFO), guaiacol peroxidase (GPX) and phospholipase D (PLD), at the stem's symplastic level during the interaction with the pathogen. An in vivo assay was established using two carnation cultivars presenting contrasting levels of resistance to the disease, and the levels of SA, MeSA (Methyl salicylate) and the named enzymes were determined. Induction of the studied enzymes occurred, showing an increase at the transcriptional level in the case of the GPX enzyme. Likewise, an increase of MeSA was presented at 1 and 14 dpi, while SA was accumulated at later times. The Pearson correlation determined that on this level there is an accumulation of the MeSA hormone on 1 dpi with the levels of the enzymes GPX and PLD. We proposed that the response on the stem symplast can be activated by the signaling pathway that involves SA, affecting the secondary metabolism and the regulation of reactive species of oxygen.

Synergistic effect of oilseed cake and biocontrol agent in the suppression of Fusarium wilt in Solanum lycopersicum.

The antagonistic efficacy of a biocontrol agent in combination with oilseed cake against fungal phytopathogens has been sparsely explored. The present study aimed to evaluate the antifungal activity of a biocontrol agent (Trichoderma harzianum MTCC 3928) formulated with oilseed cake (OSC) against Fusarium oxysporum f. sp. lycopersici responsible for causing vascular wilt in Solanum lycopersicum. In in vitro studies, OSC of mustard (Brassica juncea) exhibited significant mycelial inhibition against the pathogen. The volatile plate assay showed mycelial inhibition of 70 and 40% with unautoclaved and autoclaved mustard cakes, respectively. The aqueous extract (10% v/v) of the mustard cake was the most effective with 47.3% mycelial inhibition of pathogen over control. In addition, volatiles and aqueous extract of mustard cake subjected to GC-MS analysis revealed a range of antifungal bioactive compounds with hexanedioic acid, dioctyl ester (16.57%), and oleic acid trimethylsilyl ester (12.41%) being predominant compounds. In in vitro studies, it was noticed that the T. harzianum strain was compatible with mustard cake, and hence used as a growth substrate for its mass multiplication. SEM analysis revealed no distortion in spores and mycelium of T. harzianum grown on the mustard cake. Further, seed germination assay suggested the optimum concentration of mustard cake (10%) supporting the germination rate and economics of formulation development. In in planta assay, the combination of biocontrol agent and mustard cake showed 48% disease reduction, and ~ 40% with T. harzianum alone in comparison to untreated control. Also, the combination of mustard cake and T. harzianum significantly enhanced the growth parameters of S. lycopersicum. The findings of the current study identified an environmentally friendly alternative for mitigation of Fusarium wilt, thereby providing a sustainable option for mitigation of wilt disease and enhancement of plant health.

Chemical composition, aerobic stability, and fermentation pattern of white oat silage wilted with glyphosate / Composição química, estabilidade aeróbia e padrão fermentativo de silagens de aveia branca dessecadas com glifosato

White oat has good nutritional quality but is not an easy forage to ensile due to its high buffer capacity and moisture content at ensiling moment. Therefore, wilting is necessary to offset such negative aspects. However, this process demands skilled workforce and adequate machinery. In this way, chemical desiccation is a promising technology to reduce the steps needed for wilting. Thus, we aimed to evaluate the effects of glyphosate as a chemical desiccant on the nutritional quality, fermentation pattern, losses, and aerobic stability of wilted white oat (Avena sativa) silages. White oat sowing occurred in the first fortnight of May 2013. Desiccant application took place when oat reached milky-dough grain stage (96 days after planting). Glyphosate doses evaluated were 0, 500, 750, 1000, and 1250 mL ha-1. Three days after desiccation, all treatments were ensiled, and the silos were stored for 150 days. A completely randomized design was used, and all statistical procedures were performed by means of Bayesian Inference. No differences were found for lactic acid, but treated-silage pH linearly decreased. The lowest concentration of butyric acid (3.40 mg kg-1) was observed at 900.80 mL ha-1. For ammonia, the highest point (50 g kg-1) occurred at 916.51 mL ha-1. Aerobic stability was not influenced by treatments. Maximum dry matter recovery index (934 g kg-1) was observed at 864.20mL ha-1 glyphosate. Wilted forage from treatments 500 mL ha-1, 750 mL ha-1, and 1000 mL ha-1 had greater dry matter content compared to control (320.1, 326, 301.3, and 270.7 g kg-1 respectively). Hemicellulose linearly decreased and crude protein linearly increased. The lowest concentrations of neutral detergent fiber (642.8 g kg-1) and neutral-detergent insoluble nitrogen (2.30 g kg-1) occurred at doses of 1141.32 mL ha-1 and 829.14 mL ha-1, respectively. In brief, for wilted white oat silage production, harvested at milky-dough grain stage, glyphosate application...(AU)

A aveia branca (Avena sativa) apresenta boa qualidade nutricional, contudo, devido à sua alta capacidade tampão e elevado teor de umidade no momento do corte, acaba por dificultar o processo de conservação como silagem. Dessa forma, a pré-secagem é necessária para compensar os aspectos negativos relacionados à ensilagem da aveia. No entanto, a pré-secagem exige mão-de-obra qualificada bem como maquinário específico. Desta forma, a dessecação química é uma tecnologia promissora, reduzindo as etapas necessárias para a pré-secagem, facilitando o processo. Sendo assim, objetivou-se foi avaliar os efeitos do uso do glifosato na pré-secagem da avia branca sobre a qualidade nutricional, padrão de fermentativo e perdas bem como na estabilidade aeróbia das silagens resultantes. A semeadura de aveia branca ocorreu na primeira quinzena de maio de 2013. A aplicação do dessecante ocorreu quando a aveia atingiu o estágio de grãos leitoso/pastoso (96 dias após o plantio). As doses de glifosato avaliadas foram 0, 500, 750, 1000 e 1250 mL ha-1. Três dias após a dessecação, todos os tratamentos foram ensilados e os silos foram armazenados por 150 dias. O delineamento experimental foi o inteiramente casualizado e todos os procedimentos estatísticos foram realizados por meio da inferência bayesiana. Não foram encontradas diferenças para as concentrações de ácido láctico, no entanto, o pH diminuiu linearmente nas silagens tratadas. A menor concentração de ácido butírico (3,40 mg kg-1) foi observada para a dosem de 900,80 mL ha-1. A maior concentração de amônia (50 g kg-1) foi encontrada na dosem de 916,51 mL ha-1. A estabilidade aeróbica não foi influenciada pelos tratamentos neste estudo. O maior índice de recuperação de matéria seca (934 g kg-1) foi observado para a dosem de 864,20 mL ha-1 de glifosato. As silagens provenientes dos tratamentos 500 mL ha-1, 750 mL ha-1 e 1000 mL ha-1 apresentaram...(AU)

Chemical composition, aerobic stability, and fermentation pattern of white oat silage wilted with glyphosate / Composição química, estabilidade aeróbia e padrão fermentativo de silagens de aveia branca dessecadas com glifosato

White oat has good nutritional quality but is not an easy forage to ensile due to its high buffer capacity and moisture content at ensiling moment. Therefore, wilting is necessary to offset such negative aspects. However, this process demands skilled workforce and adequate machinery. In this way, chemical desiccation is a promising technology to reduce the steps needed for wilting. Thus, we aimed to evaluate the effects of glyphosate as a chemical desiccant on the nutritional quality, fermentation pattern, losses, and aerobic stability of wilted white oat (Avena sativa) silages. White oat sowing occurred in the first fortnight of May 2013. Desiccant application took place when oat reached milky-dough grain stage (96 days after planting). Glyphosate doses evaluated were 0, 500, 750, 1000, and 1250 mL ha-1. Three days after desiccation, all treatments were ensiled, and the silos were stored for 150 days. A completely randomized design was used, and all statistical procedures were performed by means of Bayesian Inference. No differences were found for lactic acid, but treated-silage pH linearly decreased. The lowest concentration of butyric acid (3.40 mg kg-1) was observed at 900.80 mL ha-1. For ammonia, the highest point (50 g kg-1) occurred at 916.51 mL ha-1. Aerobic stability was not influenced by treatments. Maximum dry matter recovery index (934 g kg-1) was observed at 864.20mL ha-1 glyphosate. Wilted forage from treatments 500 mL ha-1, 750 mL ha-1, and 1000 mL ha-1 had greater dry matter content compared to control (320.1, 326, 301.3, and 270.7 g kg-1 respectively). Hemicellulose linearly decreased and crude protein linearly increased. The lowest concentrations of neutral detergent fiber (642.8 g kg-1) and neutral-detergent insoluble nitrogen (2.30 g kg-1) occurred at doses of 1141.32 mL ha-1 and 829.14 mL ha-1, respectively. In brief, for wilted white oat silage production, harvested at milky-dough grain stage, glyphosate application...

A aveia branca (Avena sativa) apresenta boa qualidade nutricional, contudo, devido à sua alta capacidade tampão e elevado teor de umidade no momento do corte, acaba por dificultar o processo de conservação como silagem. Dessa forma, a pré-secagem é necessária para compensar os aspectos negativos relacionados à ensilagem da aveia. No entanto, a pré-secagem exige mão-de-obra qualificada bem como maquinário específico. Desta forma, a dessecação química é uma tecnologia promissora, reduzindo as etapas necessárias para a pré-secagem, facilitando o processo. Sendo assim, objetivou-se foi avaliar os efeitos do uso do glifosato na pré-secagem da avia branca sobre a qualidade nutricional, padrão de fermentativo e perdas bem como na estabilidade aeróbia das silagens resultantes. A semeadura de aveia branca ocorreu na primeira quinzena de maio de 2013. A aplicação do dessecante ocorreu quando a aveia atingiu o estágio de grãos leitoso/pastoso (96 dias após o plantio). As doses de glifosato avaliadas foram 0, 500, 750, 1000 e 1250 mL ha-1. Três dias após a dessecação, todos os tratamentos foram ensilados e os silos foram armazenados por 150 dias. O delineamento experimental foi o inteiramente casualizado e todos os procedimentos estatísticos foram realizados por meio da inferência bayesiana. Não foram encontradas diferenças para as concentrações de ácido láctico, no entanto, o pH diminuiu linearmente nas silagens tratadas. A menor concentração de ácido butírico (3,40 mg kg-1) foi observada para a dosem de 900,80 mL ha-1. A maior concentração de amônia (50 g kg-1) foi encontrada na dosem de 916,51 mL ha-1. A estabilidade aeróbica não foi influenciada pelos tratamentos neste estudo. O maior índice de recuperação de matéria seca (934 g kg-1) foi observado para a dosem de 864,20 mL ha-1 de glifosato. As silagens provenientes dos tratamentos 500 mL ha-1, 750 mL ha-1 e 1000 mL ha-1 apresentaram...

Permanent wilt point from two methods for different combinations of citrus rootstock / Ponto de murcha permanete a partir de dois métodos para diferentes combinações copa porta-enxerto de citros

Considering that water is extremely important in agricultural production, but with restricted availability in some Brazilian regions, this research sought to identify the water limit for the rootstocks: Cleóptra tangerine (Citrus reshni hort. Ex Tan), Volkamer lime (Citrus Volkameriano Pasquale), Citrandarin ‘indio (TSK X TRENG 256), Santa Cruz Rangpur lime (Citrus × limonia) and Sunki Tropical tangerine (Citrus sunki HORT. EX TAN) grafted orange ‘Pera (Citrus sinensis), obtained by two methods: the traditional method of determining the permanent wilting point described by SHANTZ & BRIGGS (1912) recovery of plants with saturated environment and by irrigating recovery method. The experimental design used was in a completely randomized design with four replications totaling 20 experimental plots. It was verified that the rootstocks Cravo Santa Cruz lemon and Volkamerian lemon were the most resistant in initial conditions of water restriction, evaluated by the method of BRIGGS & SHANTZ (1912), with recording of humidity of 0.0488 and 0.0489 respectively. Under more severe conditions of water restriction, determined by the irrigation method, Volkamerian lemon presented the highest resistance, with a humidity of 0.0371.(AU)

Considerando que a água é extremamente importante na produção agrícola, mas com restrita disponibilidade em algumas regiões brasileiras, é que esse trabalho buscou identificar o limite hídrico inferior para os porta-enxertos: tangerina Cleóptra (Citrus reshni hort. Ex Tan), limão Volkameriano (Citrus Volkameriano Pasquale), citrandarin ‘Indio -TSK X TRENG 256, limão Cravo Santa Cruz (Citrus × limonia) e tangerina Sunki Tropical (Citrus sunki HORT. EX TAN) enxertadas em laranja ‘Pêra (Citrus sinensis), obtidos por dois métodos: o método tradicional de determinação do ponto de murchamento permanente descrito por BRIGGS & SHANTZ (1912) com recuperação das plantas em ambiente saturado e o método de recuperação por rega. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições, totalizando 20 parcelas experimentais. Verificou-se que os porta-enxertos limão Cravo Santa Cruz e o limão Volkameriano foram os mais resistentes em condições iniciais de restrição hídrica, avaliado pelo método de BRIGGS & SHANTZ (1912), com registro das umidades de 0,0488 e 0,0489, respectivamente. Em condições mais severas de restrição hídrica, determinado pelo método de rega, o limão Volkameriano foi o que apresentou maior resistência, com a umidade de 0,0371.(AU)

Permanent wilt point from two methods for different combinations of citrus rootstock / Ponto de murcha permanete a partir de dois métodos para diferentes combinações copa porta-enxerto de citros

ABSTRACT: Considering that water is extremely important in agricultural production, but with restricted availability in some Brazilian regions, this research sought to identify the water limit for the rootstocks: Cleóptra tangerine (Citrus reshni hort. Ex Tan), Volkamer lime (Citrus Volkameriano Pasquale), Citrandarin 'indio' (TSK X TRENG 256), Santa Cruz Rangpur lime (Citrus × limonia) and Sunki Tropical tangerine (Citrus sunki HORT. EX TAN) grafted orange 'Pera' (Citrus sinensis), obtained by two methods: the traditional method of determining the permanent wilting point described by SHANTZ & BRIGGS (1912) recovery of plants with saturated environment and by irrigating recovery method. The experimental design used was in a completely randomized design with four replications totaling 20 experimental plots. It was verified that the rootstocks Cravo Santa Cruz lemon and Volkamerian lemon were the most resistant in initial conditions of water restriction, evaluated by the method of BRIGGS & SHANTZ (1912), with recording of humidity of 0.0488 and 0.0489 respectively. Under more severe conditions of water restriction, determined by the irrigation method, Volkamerian lemon presented the highest resistance, with a humidity of 0.0371.

RESUMO: Considerando que a água é extremamente importante na produção agrícola, mas com restrita disponibilidade em algumas regiões brasileiras, é que esse trabalho buscou identificar o limite hídrico inferior para os porta-enxertos: tangerina Cleóptra (Citrus reshni hort. Ex Tan), limão Volkameriano (Citrus Volkameriano Pasquale), citrandarin 'Indio' -TSK X TRENG 256, limão Cravo Santa Cruz (Citrus × limonia) e tangerina Sunki Tropical (Citrus sunki HORT. EX TAN) enxertadas em laranja 'Pêra' (Citrus sinensis), obtidos por dois métodos: o método tradicional de determinação do ponto de murchamento permanente descrito por BRIGGS & SHANTZ (1912) com recuperação das plantas em ambiente saturado e o método de recuperação por rega. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições, totalizando 20 parcelas experimentais. Verificou-se que os porta-enxertos limão Cravo Santa Cruz e o limão Volkameriano foram os mais resistentes em condições iniciais de restrição hídrica, avaliado pelo método de BRIGGS & SHANTZ (1912), com registro das umidades de 0,0488 e 0,0489, respectivamente. Em condições mais severas de restrição hídrica, determinado pelo método de rega, o limão Volkameriano foi o que apresentou maior resistência, com a umidade de 0,0371.

Nutritional composition of ‘Ponta Negra forage sorghum silage enriched with dried Leucaena leucocephala forage / Composição nutricional da silagem de sorgo forrageiro Ponta Negra aditivada com forragem de leucena (Leucaena leucocephala) desidratada

The aim of this study was to evaluate fermentation and chemical characteristics and the in situ degradability of sorghum silages enriched with dried Leucaena. The experiment was conducted as completely randomized design with four treatments (0 - control silage, silage without leucaena; 10.0, 20.0, or 30.0% inclusion of Leucaena) and five replicates, totaling 20 experimental units. The inclusion levels of leucaena influenced (P <0.05) the pH values, and for each 1% inclusion there was a reduction of 0.0023 points in the pH value, and in all silages presented values. Dry matter recovery did not show effect (P > 0.05), with all silages having values above 90%. Gas loss decreased (P < 0.05) as the level of leucine increased in sorghum silage. A linear increase was observed for dry matter (P ≤ 0.0001) and crude protein (P = 0.0008) contents in response to Leucaena inclusion. There was a linear (P < 0.05) linear effect on neutral detergent fiber, hemicellulose and acid detergent fiber. As leucaena inclusion levels increased, for each 1% inclusion a reduction of 0.179 was observed; 0.059 and 0.119% for the values of neutral detergent fiber, hemicellulose and acid detergent fiber respectively. The inclusion of leucaena influenced (P < 0.05) the increase of silage lignin levels, probably due to the higher lignin content of the legume. The soluble fraction (a) of the silages increased along with the Leucaena inclusion levels, with highest values observed at the inclusion of 20 and 30% of the legume, respectively. Potential degradation (A) increased linearly with the levels of Leucaena added to the silage; the highest value for this variable was observed at 30% inclusion. Effective degradability (ED) increased up to the inclusion level of 20% (46.77%). Degradation rate (c) decreased markedly with the use of 30% Leucaena...(AU)

O objetivo deste trabalho foi avaliar as características fermentativas e químicas e a degradabilidade in situ de silagens de sorgo enriquecidas com Leucaena desidratada. O experimento foi conduzido em delineamento inteiramente casualizado, com quatro tratamentos (0 - silagem controle, silagem sem leucena; 10,0, 20,0 ou 30,0% de inclusão de leucena) e cinco repetições, totalizando 20 unidades experimentais. Os níveis de inclusão da leucena influenciaram (P < 0,05) os valores de pH, sendo que para cada 1% de inclusão houve redução de 0,0023 pontos no valor do pH, sendo que em todas as silagens apresentaram valores ideias. A recuperação de matéria seca não apresentou efeito (P > 0,05), sendo que todas as silagens apresentaram valores acima de 90%. A perda de gases reduziu (P < 0,05), à medida que aumentou o nível de leucina na silagem de sorgo. A linear increase was observed for dry matter (P ≤ 0, 0001) and crude protein (P = 0.0008) contents in response to Leucaena inclusion. Observou-se efeito (P < 0,05) linear decrescente a fibra em detergente neutro, hemicelulose e fibra em detergente ácido. À medida que se elevou os níveis de inclusão da leucena, para cada 1% de inclusão foi observada redução de 0,179; 0,059 e 0,119% para os valores de fibra em detergente neutro, hemicelulose e fibra em detergente ácido, respectivamente. A inclusão de leucena influenciou (P < 0.05) o aumento dos níveis de lignina da silagem, provavelmente pelo maior teor de lignina da leguminosa. A fração solúvel (a) das silagens aumentou juntamente com os níveis de inclusão de leucena, com maiores valores observados na inclusão de 20 e 30% da leguminosa, respectivamente. A degradação potencial (A) aumentou linearmente com os níveis de Leucaena adicionados à silagem; o maior valor para essa variável foi observado em 30% de inclusão. A degradabilidade efetiva (DE) aumentou até o nível de inclusão de 20% (46,77%). Taxa de degradação (c) diminuiu acentuadamente com o uso de 30% de Leucena...(AU)

Nutritional composition of ‘Ponta Negra’ forage sorghum silage enriched with dried Leucaena leucocephala forage / Composição nutricional da silagem de sorgo forrageiro Ponta Negra aditivada com forragem de leucena (Leucaena leucocephala) desidratada

The aim of this study was to evaluate fermentation and chemical characteristics and the in situ degradability of sorghum silages enriched with dried Leucaena. The experiment was conducted as completely randomized design with four treatments (0 - control silage, silage without leucaena; 10.0, 20.0, or 30.0% inclusion of Leucaena) and five replicates, totaling 20 experimental units. The inclusion levels of leucaena influenced (P 0.05), with all silages having values above 90%. Gas loss decreased (P < 0.05) as the level of leucine increased in sorghum silage. A linear increase was observed for dry matter (P ≤ 0.0001) and crude protein (P = 0.0008) contents in response to Leucaena inclusion. There was a linear (P < 0.05) linear effect on neutral detergent fiber, hemicellulose and acid detergent fiber. As leucaena inclusion levels increased, for each 1% inclusion a reduction of 0.179 was observed; 0.059 and 0.119% for the values of neutral detergent fiber, hemicellulose and acid detergent fiber respectively. The inclusion of leucaena influenced (P < 0.05) the increase of silage lignin levels, probably due to the higher lignin content of the legume. The soluble fraction (a) of the silages increased along with the Leucaena inclusion levels, with highest values observed at the inclusion of 20 and 30% of the legume, respectively. Potential degradation (A) increased linearly with the levels of Leucaena added to the silage; the highest value for this variable was observed at 30% inclusion. Effective degradability (ED) increased up to the inclusion level of 20% (46.77%). Degradation rate (c) decreased markedly with the use of 30% Leucaena...

O objetivo deste trabalho foi avaliar as características fermentativas e químicas e a degradabilidade in situ de silagens de sorgo enriquecidas com Leucaena desidratada. O experimento foi conduzido em delineamento inteiramente casualizado, com quatro tratamentos (0 - silagem controle, silagem sem leucena; 10,0, 20,0 ou 30,0% de inclusão de leucena) e cinco repetições, totalizando 20 unidades experimentais. Os níveis de inclusão da leucena influenciaram (P 0,05), sendo que todas as silagens apresentaram valores acima de 90%. A perda de gases reduziu (P < 0,05), à medida que aumentou o nível de leucina na silagem de sorgo. A linear increase was observed for dry matter (P ≤ 0, 0001) and crude protein (P = 0.0008) contents in response to Leucaena inclusion. Observou-se efeito (P < 0,05) linear decrescente a fibra em detergente neutro, hemicelulose e fibra em detergente ácido. À medida que se elevou os níveis de inclusão da leucena, para cada 1% de inclusão foi observada redução de 0,179; 0,059 e 0,119% para os valores de fibra em detergente neutro, hemicelulose e fibra em detergente ácido, respectivamente. A inclusão de leucena influenciou (P < 0.05) o aumento dos níveis de lignina da silagem, provavelmente pelo maior teor de lignina da leguminosa. A fração solúvel (a) das silagens aumentou juntamente com os níveis de inclusão de leucena, com maiores valores observados na inclusão de 20 e 30% da leguminosa, respectivamente. A degradação potencial (A) aumentou linearmente com os níveis de Leucaena adicionados à silagem; o maior valor para essa variável foi observado em 30% de inclusão. A degradabilidade efetiva (DE) aumentou até o nível de inclusão de 20% (46,77%). Taxa de degradação (c) diminuiu acentuadamente com o uso de 30% de Leucena...

Fermentation pattern of tropical grass haylage and digestibility compared to hay in equine diet / Padrão de fermentação da silagem de gramínea tropical e digestibilidade comparada ao feno na dieta de equinos

Hay production is the most common form of forage conservation methods for horse feeding. However, haylage can be an alternative to hay. The present research assessed the nutritional value of Tifton-85 haylage by fermentation pattern, bromatological composition, and apparent digestibility compared to hay in the diet of Quarter Horse mares. Haylage was prepared with 700.0 g of dry matter (DM) kg-¹ added with a biological inoculum and was assessed at 1, 3, 7, 14, 28, and 56 days of production. At 14 days, the protein content had decreased from 192.0 to 173.2 g kg-¹ DM. The opposite was found for ammoniacal nitrogen, which rose from 0.61 to 1.14 g kg-¹ DM of total nitrogen. No differences were found for the variables NDF, ADF, hemicellulose, pH, acetic acid, propionic acid and butyric acid, whose values were 734.3, 316.5 and 416.9 g kg-¹ DM, pH 5.47 and 0.06, 0.003, 0.03 g kg-¹ DM, respectively. Lactic acid contents were higher after 28 days of haylage production, reaching 2.39 g kg-¹ DM at the last assessment. The contents of aflatoxins, fumonisin, and zearalenone in the plant were similar to those in the haylage at 0.95 µg kg-¹, 0.60 mg kg-¹, and 0.71 µg kg-¹, respectively. The digestibility assay showed an increase in protein digestibility in the diet with haylage (675.1 g kg-¹ DM) compared to hay (579.1 g kg-¹ DM) of the same grass. Haylage can potentially be used to feed horses and its use is recommended starting at 28 days of production.(AU)

A produção de feno é a forma mais comum entre os métodos de conservação de forragem para alimentação de cavalos. Entretanto, a silagem pode ser alternativa ao uso do feno. A presente pesquisa avaliou o valor nutricional da silagem de Tifton-85 através do padrão de fermentação, composição bromatológica e digestibilidade aparente, em comparação com feno na dieta de éguas da raça Quarto de Milha. Foram confeccionadas silagens com 700,0 g matéria seca (MS) kg-¹ e aditivada com inoculante biológico, as quais foram avaliadas 1, 3, 7, 14, 28 e 56 dias de produção. Aos 14 dias foi verificado redução na concentração proteica de 192,0 para 173,2 g kg-¹ MS. O inverso foi encontrado para o nitrogênio amoniacal que aumentou de 0,61 para 1,14 do nitrogênio total. Não foram verificadas diferenças para as variáveis FDN, FDA, hemicelulose, pH, ácido acético, propiônico e butírico que apresentaram 734,3; 316,5; 416,9 g kg-¹ MS, pH 5,47 e 0,06; 0,003; 0,03 g kg-¹ MS, respectivamente. As concentrações de ácido láctico foram superiores a partir dos 28 dias de produção, atingindo 2,39 g kg-¹ MS no último tempo avaliado. As concentrações de aflatoxinas, fumonisina e zearalenona foram semelhantes entre planta e silagem, que foram 0,95 µg kg-¹; 0,60 mg kg-¹ e 0,71 µg kg-¹, respectivamente. No ensaio de digestibilidade, foi verificado aumento na digestibilidade da proteína na dieta com silagem (675,1 g kg-¹) quando comparada ao feno (579,1 g kg-¹) da mesma gramínea. A silagem apresenta potencial para utilização na alimentação de equinos sendo recomendada sua utilização a partir de 28 dias de ensilada.(AU)

A comprehensive evaluation of pedotransfer functions for predicting soil water content in environmental modeling and ecosystem management.

Many pedotransfer functions (PTFs) have been developed for predicting the soil water content at different matric potentials. The use of these functions has been encouraged because of the time and work typically required for measuring it, while the PTFs require commonly measured soil properties such as sand, silt, clay, organic matter content, or bulk density for predicting water retention. In addition, several environmental and ecosystem management simulation models such as DRAINMOD, HYDRUS, EPIC, SPAW, and WEPP use PTFs for computing soil hydraulic properties. Because of the increasing use of the PTFs and their effect in many soil water simulation and transport models, this study revised and tested 13 different PTFs for predicting soil water content at -33 and -1500 kPa, values usually known as field capacity and wilting point. Three of these PTFs were derived from tropical soils while the rest were developed with soil samples collected across the United States. These PTFs were evaluated in Chilean soils as an independent dataset and their improvement after calibration was assessed with this new data. The results demonstrate that the PTFs performance depends on the soils used for their development as the estimates showed a significant improvement after calibration. When predicting water content, Rawls et al. (2004) was the best function before calibration (RMSE = 0.08 for -33 and -1500 kPa), while Gupta and Larson (1979) was the best after calibration (RMSE of 0.06 and 0.05, and r2 values of 0.69 and 0.66 at -33 and -1500 kPa, respectively). Nonlinear PTFs performed better than linear PTFs when predicting water content at field capacity. Finally, bulk density proved to be the key variable and can be used as footprint for soils changes through time. Organic matter content was also a significant input but improved the estimates for some specific matric potentials and PTFs.

Fermentation pattern of tropical grass haylage and digestibility compared to hay in equine diet / Padrão de fermentação da silagem de gramínea tropical e digestibilidade comparada ao feno na dieta de equinos

Hay production is the most common form of forage conservation methods for horse feeding. However, haylage can be an alternative to hay. The present research assessed the nutritional value of Tifton-85 haylage by fermentation pattern, bromatological composition, and apparent digestibility compared to hay in the diet of Quarter Horse mares. Haylage was prepared with 700.0 g of dry matter (DM) kg-¹ added with a biological inoculum and was assessed at 1, 3, 7, 14, 28, and 56 days of production. At 14 days, the protein content had decreased from 192.0 to 173.2 g kg-¹ DM. The opposite was found for ammoniacal nitrogen, which rose from 0.61 to 1.14 g kg-¹ DM of total nitrogen. No differences were found for the variables NDF, ADF, hemicellulose, pH, acetic acid, propionic acid and butyric acid, whose values were 734.3, 316.5 and 416.9 g kg-¹ DM, pH 5.47 and 0.06, 0.003, 0.03 g kg-¹ DM, respectively. Lactic acid contents were higher after 28 days of haylage production, reaching 2.39 g kg-¹ DM at the last assessment. The contents of aflatoxins, fumonisin, and zearalenone in the plant were similar to those in the haylage at 0.95 µg kg-¹, 0.60 mg kg-¹, and 0.71 µg kg-¹, respectively. The digestibility assay showed an increase in protein digestibility in the diet with haylage (675.1 g kg-¹ DM) compared to hay (579.1 g kg-¹ DM) of the same grass. Haylage can potentially be used to feed horses and its use is recommended starting at 28 days of production.

A produção de feno é a forma mais comum entre os métodos de conservação de forragem para alimentação de cavalos. Entretanto, a silagem pode ser alternativa ao uso do feno. A presente pesquisa avaliou o valor nutricional da silagem de Tifton-85 através do padrão de fermentação, composição bromatológica e digestibilidade aparente, em comparação com feno na dieta de éguas da raça Quarto de Milha. Foram confeccionadas silagens com 700,0 g matéria seca (MS) kg-¹ e aditivada com inoculante biológico, as quais foram avaliadas 1, 3, 7, 14, 28 e 56 dias de produção. Aos 14 dias foi verificado redução na concentração proteica de 192,0 para 173,2 g kg-¹ MS. O inverso foi encontrado para o nitrogênio amoniacal que aumentou de 0,61 para 1,14 do nitrogênio total. Não foram verificadas diferenças para as variáveis FDN, FDA, hemicelulose, pH, ácido acético, propiônico e butírico que apresentaram 734,3; 316,5; 416,9 g kg-¹ MS, pH 5,47 e 0,06; 0,003; 0,03 g kg-¹ MS, respectivamente. As concentrações de ácido láctico foram superiores a partir dos 28 dias de produção, atingindo 2,39 g kg-¹ MS no último tempo avaliado. As concentrações de aflatoxinas, fumonisina e zearalenona foram semelhantes entre planta e silagem, que foram 0,95 µg kg-¹; 0,60 mg kg-¹ e 0,71 µg kg-¹, respectivamente. No ensaio de digestibilidade, foi verificado aumento na digestibilidade da proteína na dieta com silagem (675,1 g kg-¹) quando comparada ao feno (579,1 g kg-¹) da mesma gramínea. A silagem apresenta potencial para utilização na alimentação de equinos sendo recomendada sua utilização a partir de 28 dias de ensilada.

Stronger seasonal adjustment in leaf turgor loss point in lianas than trees in an Amazonian forest.

Pan-tropically, liana density increases with decreasing rainfall and increasing seasonality. This pattern has led to the hypothesis that lianas display a growth advantage over trees under dry conditions. However, the physiological mechanisms underpinning this hypothesis remain elusive. A key trait influencing leaf and plant drought tolerance is the leaf water potential at turgor loss point (πtlp). πtlp adjusts under drier conditions and this contributes to improved leaf drought tolerance. For co-occurring Amazonian tree (n = 247) and liana (n = 57) individuals measured during the dry and the wet seasons, lianas showed a stronger osmotic adjustment than trees. Liana leaves were less drought-tolerant than trees in the wet season, but reached similar drought tolerances during the dry season. Stronger osmotic adjustment in lianas would contribute to turgor maintenance, a critical prerequisite for carbon uptake and growth, and to the success of lianas relative to trees in growth under drier conditions.