Spatial and seasonal responses of diazotrophs and ammonium-oxidizing bacteria to legume-based silvopastoral systems

ABSTRACT: Find shade-tolerant species is essential to the success of silvopastoral systems, increasingly frequent in recent years. In legumes, which have potential of biological nitrogen fixation, there is a great lack of knowledge when in shaded environments.The cultivation of four tropical forage (Neonotonia wightii, Pueraria phaseoloides, Macrotyloma axilare and Arachis pintoi) was evaluated when submitted to artificial shade levels (30, 50 and 70% shade) and in full sun during water and drought seasons. The design used was in randomized complete blocks in a sub-divided plot scheme with four replications. In the Water-season the Forage Peanuts had higher forage production in full sun (11 ton ha-1 DM), and under shade did not differ from Perennial Soybean, higher than the others in all levels of shade. In Drought-season the forage production was 61% lower than in Water-season. The highest crude protein levels were reported in Forage Peanuts, Tropical Kudzu and Perennial Soybean, 19.0; 18.3 and 18.2% respectively in the Water-season. Forage Peanuts is a good option for use in silvopastoral systems although there is a small reduction in forage production (average of 23.7%). In general, species of fabaceae showed a greater reduction in forage production in the period of water deficit; however, shading at levels of 30% to 50% contribute to mitigation of water shortage. Although, there is a small reduction in forage production, withexception of perennial soybeans in dry season, it is advisable to use tropical forage legumes in silvopastoral systems, since forage quality is not affected by shade.

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Artificial light at night alters the seasonal responses of biting mosquitoes

Journal of Insect Physiology ◽

10.1016/j.jinsphys.2021.104194 ◽

2021 ◽

Vol 129 ◽

pp. 104194

Author(s):

Lydia R. Fyie ◽

Mary M. Gardiner ◽

Megan E. Meuti

Keyword(s):

Artificial Light ◽

Light At Night ◽

Seasonal Responses

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Control of torpor and body weight patterns by a seasonal timer in Siberian hamsters

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1989.257.1.r142 ◽

1989 ◽

Vol 257 (1) ◽

pp. R142-R149 ◽

Cited By ~ 8

Author(s):

T. J. Bartness ◽

J. A. Elliott ◽

B. D. Goldman

Keyword(s):

Body Weight ◽

Food Intake ◽

Implant Removal ◽

Daily Torpor ◽

Short Day ◽

Siberian Hamsters ◽

Long Day ◽

Preparatory Phase ◽

Pelage Color ◽

Seasonal Responses

Two experiments were designed to assess whether the short-day-induced patterns of shallow daily torpor, body weight, and other seasonal responses (food intake and pelage pigmentation) exhibited by Siberian hamsters (Phodopus sungorus sungorus) are under the control of a "seasonal timekeeping mechanism" that is independent of reproductive status [testosterone, (T)]. We examined whether the patterning and expression of these seasonal responses were altered by decreases in serum T that accompany gonadal regression during the first 8 wk of short-day exposure (i.e., the "preparatory phase" of the torpor season) or by experimental increases in serum T after this phase. Short-day-housed, castrated hamsters bearing T implants had long-day levels of the hormone and did not exhibit torpor. Appropriate seasonal patterns and levels of torpor, body weight, pelage color stage, and food intake were exhibited after T implant removal although serum T was clamped to long-day levels during the preparatory phase. In animals that were gonad intact during the preparatory phase and were subsequently castrated and given T implants, torpor did not occur as long as the implants were in place. However, the patterns and levels of daily torpor, food intake, and body weight rapidly returned to appropriate seasonal values compared with the castrated, blank-implanted controls on T implant removal; these effects occurred whether the T implants were removed when torpor frequency was increasing, at its peak, or decreasing across the torpor season. T did not affect pelage color stage under any condition.(ABSTRACT TRUNCATED AT 250 WORDS)

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Disentangling the Role of Management Practices on Ecosystem Services Delivery in Mediterranean Silvopastoral Systems: Synergies and Trade-Offs Through Expert-Based Assessment

SSRN Electronic Journal ◽

10.2139/ssrn.3978427 ◽

2021 ◽

Author(s):

Antonio Lecegui ◽

Ana María Olaizola ◽

Elsa Varela

Keyword(s):

Ecosystem Services ◽

Management Practices ◽

Silvopastoral Systems ◽

Services Delivery ◽

Trade Offs

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GROWTH OF DIFFERENT FRUIT TREE SPECIES IN SILVOPASTORAL SYSTEMS DURING THE ESTABLISHMENT PHASE

Revista Caatinga ◽

10.1590/1983-21252017v30n425rc ◽

2017 ◽

Vol 30 (4) ◽

pp. 1040-1049 ◽

Cited By ~ 1

Author(s):

CAROLINA DELLA GIUSTINA ◽

ROBERTA APARECIDA CARNEVALLI ◽

MARCELO RIBEIRO ROMANO ◽

DIEGO BARBOSA ALVES ANTONIO ◽

CAMILA ECKSTEIN

Keyword(s):

Tree Species ◽

Block Design ◽

Control Plant ◽

Fruit Trees ◽

Fruit Tree ◽

Silvopastoral Systems ◽

Area Index ◽

Mato Grosso ◽

Plant Accumulation ◽

Establishment Phase

ABSTRACT The benefits of integrating agricultural components into silvopastoral systems are widely known, but the limited knowledge about ecological processes in the establishment phase impedes the use of this technology. The objective of this study was to evaluate interactions between fruit tree species and the sward layer under canopies of trees in the establishment phase of silvopastoral systems in Mato Grosso, Brazil. The experiment was implemented in October 2013, with an evaluation period from January to July 2015. The systems were composed of eight fruit trees intercropped with Tifton 85 grass. A completely randomized block design was adopted, with two replications per area per treatment. We evaluated the agronomic performance of the fruit trees, the categories of the light environment, and the plant accumulation under the canopies. The acerola fruit trees of the variety Roxinha had higher Leaf area index (LAI) and Light interception (LI) values, showing a denser canopy with small porosity and the lowest light quality available to the plants beneath the canopy (lower red/far-red ratio), thereby decreasing plant accumulation under trees. The guava fruit trees showed higher growth rates than the other fruit trees, but lower LAI and LI values and a higher red/far-red ratio, allowing higher plant growth under the canopy. Cajá trees showed a similar behavior; however, this species is deciduous, which limits its potential use in integrated systems. Banana and coconut trees were highly dependent on irrigation during the dry season. The remaining species showed an adequate growth and potential to control plant species growth under their canopies.

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Comparing silvopastoral systems and prospects in eight regions of the world

Agroforestry Systems ◽

10.1007/s10457-012-9482-z ◽

2012 ◽

Vol 86 (3) ◽

pp. 303-314 ◽

Cited By ~ 43

Author(s):

Frederick Cubbage ◽

Gustavo Balmelli ◽

Adriana Bussoni ◽

Elke Noellemeyer ◽

Anibal N. Pachas ◽

...

Keyword(s):

Silvopastoral Systems ◽

The World

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Dawn and photoperiod sensing by phytochrome A

10.1101/253989 ◽

2018 ◽

Author(s):

Daniel D Seaton ◽

Gabriela Toledo-Ortiz ◽

Akane Kubota ◽

Ashwin Ganpudi ◽

Takato Imaizumi ◽

...

Keyword(s):

Meta Analysis ◽

Transcriptional Regulator ◽

Functional Genomic ◽

Sensitive Detector ◽

Phytochrome A ◽

Direct Control ◽

Complex Regulation ◽

Subsequent Activation ◽

Seasonal Responses

AbstractIn plants, light receptors play a pivotal role in photoperiod sensing, enabling them to track seasonal progression. Photoperiod sensing arises from an interaction between the plant’s endogenous circadian oscillator and external light cues. Here, we characterise the role of phytochrome A (phyA) in photoperiod sensing. Our meta-analysis of functional genomic datasets identified phyA as a principal transcriptional regulator of morning-activated genes, specifically in short photoperiods. We demonstrate that PHYA expression is under the direct control of the PHYTOCHROME INTERACTING FACTOR transcription factors, PIF4 and PIF5. As a result, phyA protein accumulates during the night, especially in short photoperiods. At dawn phyA activation by light results in a burst of gene expression, with consequences for anthocyanin accumulation. The combination of complex regulation of PHYA transcript and the unique molecular properties of phyA protein make this pathway a sensitive detector of both dawn and photoperiod.Significance statementThe changing seasons subject plants to a variety of challenging environments. In order to deal with this, many plants have mechanisms for inferring the season by measuring the duration of daylight in a day. A number of well-known seasonal responses such as flowering are responsive to daylength or photoperiod. Here, we describe how the photoreceptor protein phytochrome A senses short photoperiods. This arises from its accumulation during long nights, as happens during winter, and subsequent activation by light at dawn. As a result of this response, the abundance of red anthocyanin pigments is increased in short photoperiods. Thus, we describe a mechanism underlying a novel seasonal phenotype in an important model plant species.

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