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1.
Zootaxa ; 5255(1): 324-335, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37045252

RESUMO

Integrated agricultural systems have been greatly expanding in Brazil and currently cover over 30 million hectares. Although these land use systems help soil and environmental quality, little is known of their impacts on earthworm communities. In the present study we evaluated earthworm abundance, biomass and species richness in various integrated and conventional agricultural production systems (pasture, crops), as well as native forest and Eucalyptus plantations. The research was carried out at Fazenda Canchim (Embrapa Livestock Southeast) and at the neighboring campus of the University de São Carlos (UFSCar), in São Carlos municipality in São Paulo state, Brazil. Two earthworm sampling methods, i.e., quantitative (25 x 25 x 20 cm deep monoliths) and qualitative (holes of similar size and niche sampling), were used in three integrated production systems, three conventional systems and two forest systems, totaling 232 quantitative samples and over 160 qualitative samples. Earthworms were counted and identified using available keys. Eight earthworm species of five families (Rhinodrilidae, Ocnerodrilidae, Megascolecidae, Benhamiidae and Glossoscolecidae) were found, with most of the 2,145 individuals being exotic or peregrine species, particularly Pontoscolex corethrurus (88% of total) and various Dichogaster spp. (8% of total). Two native species were encountered in low abundance (55 individuals), both of which are new to science (Fimoscolex n.sp.7 and Glossoscolex n.sp.9) and must still be formally described. The new species were found in the agricultural systems, but not in the native forest and the Eucalyptus plantation, where P. corethrurus and Megascolecids predominated. One unidentified Ocnerodrilid sp. was found only in the intensive pasture. Species richness was highest in the intensive pasture (7 spp.), followed by the agrosilvopastoral and agropastoral systems, highlighting the importance of integrated and pastoral systems in preserving earthworm richness and native species.


Assuntos
Eucalyptus , Oligoquetos , Animais , Ecossistema , Brasil , Florestas , Agricultura
2.
Front Vet Sci ; 9: 958751, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213395

RESUMO

Brazilian cattle production is mostly carried out in pastures, and the need to mitigate the livestock's greenhouse gas (GHG) emissions and its environmental footprint has become an important requirement. The adoption of well-suited breeds and the intensification of pasture-based livestock production systems are alternatives to optimize the sector's land use. However, further research on tropical systems is necessary. The objective of this research was to evaluate the effect of Holstein (HO) and Jersey-Holstein (JE x HO) crossbred cows in different levels of pasture intensification (continuous grazing system with low stocking rate-CLS; irrigated rotational grazing system with high stocking rate-RHS), and the interaction between these two factors on GHG mitigation. Twenty-four HO and 24 JE x HO crossbred dairy cows were used to evaluate the effect of two grazing systems on milk production and composition, soil GHG emissions, methane (CH4) emission, and soil carbon accumulation (0-100 cm). These variables were used to calculate carbon balance (CB), GHG emission intensity, the number of trees required to mitigate GHG emission, and the land-saving effect. The number of trees necessary to mitigate GHG emission was calculated, considering the C balance within the farm gate. The mitigation of GHG emissions comes from the annual growth rate and accumulation of C in eucalyptus trees' trunks. The CB of all systems and genotypes presented a deficit in carbon (C); there was no difference for genotypes, but RHS was more deficient than CLS (-4.99 to CLS and -28.72 to RHS ton CO2e..ha-1.year-1). The deficit of C on GHG emission intensity was similar between genotypes and higher for RHS (-0.480 to RHS and -0.299 to CLS kg CO2e..kg FCPCmilk-1). Lower GHG removals (0.14 to CLS higher than 0.02 to RHS kg CO2e..kg FCPCmilk-1) had the greatest influence on the GHG emission intensity of milk production. The deficit number of trees to abatement emissions was higher to HO (-46.06 to HO and -38.37 trees/cow to JE x HO) and to RHS (-51.9 to RHS and -33.05 trees/cow to CLS). However, when the results are expressed per ton of FCPCmilk, there was a difference only between pasture management, requiring -6.34 tree. ton FCPCmilk-1 for the RHS and -3.99 tree. ton FCPCmilk-1 for the CLS system. The intensification of pastures resulted in higher milk production and land-saving effect of 2.7 ha. Due to the reservation of the pasture-based dairy systems in increasing soil C sequestration to offset the GHG emissions, especially enteric CH4, planting trees can be used as a mitigation strategy. Also, the land-save effect of intensification can contribute to the issue, since the area spared through the intensification in pasture management becomes available for reforestation with commercial trees.

3.
Sci Rep ; 11(1): 14092, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238990

RESUMO

Climate change is a reality and global surface temperature is projected to rise substantially in the next 80 years. Agriculture practices will have to adapt to climate change, and also help to mitigate this effect using, among other strategies, forest conservation and management. Silvopastoral systems have been adopted in tropical climate livestock areas but their benefits on thermal comfort and reproductive performance of beef cows are not completely known. Therefore, our aims were to compare the microclimate of silvopastoral and intensive rotational unshaded grazing systems in different months and to evaluate physiological variables (Exp. 1 and 2), metabolism, and in vitro embryo production (Exp. 2) in crossbred beef females. Our hypothesis is that the silvopastoral system can improve the thermal comfort of beef heifers and cows and, consequently, also improve dry matter intake, body weight gain, and in vitro embryo production when compared to the unshaded rotational grazing system. In Exp 1, the silvopastoral system decreased body temperature and increased welfare and performance of heifers. In Exp. 2, the silvopastoral system enhanced the body weight but did not affect metabolism and the general reproductive performance, but increased the recovery rate of oocytes in primiparous cows.

4.
J Therm Biol ; 91: 102636, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32716878

RESUMO

Agroforestry systems can minimize heat stress and improve cattle welfare, but the influence of the forest component in microclimatic changes in the southern Amazon remains unclear. This study aimed to compare the thermal comfort indices in grass monoculture and integrated systems. The three systems were pasture under full sunlight (PFS), integrated (triple-row) livestock-forestry (ILFT), and integrated (single-row) livestock-forestry (ILFs), across four seasons, for two years, from June 2017 to June 2019. We assessed photosynthetically active radiation (PAR), air temperature, relative humidity, black globe temperature, and wind speed. Thermal comfort indices such as temperature-humidity index (THI), black globe temperature-humidity index (BGHI), and radiant thermal load (RTL) were calculated based on microclimate data daily-collected from 8:00 to 16:00. The ILFT mean THI (76.8) was slightly lower than ILFS and PFS. The BGHI and RTL values decreased as shading increased (PFS > ILFs > ILFT). The most challenging heat stress conditions for grazing animals occurred predominately during winter and autumn. In conclusion, the presence of trees in pastures of the southern Amazon improved the microclimate and, consequently, the thermal comfort indices. Agroforestry systems can foster an environment with a more suitable thermal comfort or less restrictive to animal performance, which contribute to mitigating global climate change for forage-livestock systems in Brazilian Amazon.


Assuntos
Agricultura/métodos , Regulação da Temperatura Corporal , Bovinos/fisiologia , Florestas , Agricultura/normas , Animais , Brasil , Aquecimento Global , Umidade , Estações do Ano , Temperatura , Clima Tropical
5.
Sci Total Environ ; 684: 587-596, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31158622

RESUMO

Pasture-based livestock production is largely centered on monoculture systems that degrade grasslands. In integrated crop-livestock-forestry systems a synergy is supposed to occur between its components, contributing to global food production. Thus, this study aimed to evaluate the effects of the microclimate on integrated crop-livestock-forestry (CLF) and crop-livestock (CL) systems on the behavior and body surface temperatures of beef cattle in a tropical climate. The experiment was carried from December/2016 to June/2017. Adult beef cows were maintained in CL (n = 11) or CLF (n = 12) systems, permanently monitored by automatic weather stations. The microclimatic conditions indicated that CLF was more effective in mitigating the environmental heat load. Animals maintained in CLF showed favorable behavior, longer rumination (42.9 ±â€¯2.2 vs 36.6 ±â€¯2.2 min) and shorter resting time (57.6 ±â€¯2.7 vs 65.9 ±â€¯2.8 min) during the morning. The grazing time and other activities did not differ between treatments (P > 0.05) in the afternoon. Animals in CLF exhibited lower surface temperatures of the back (TBack: 31.9 ±â€¯0.2 vs 32.8 ±â€¯0.2 °C, P < 0.05) and of the trunk (TTrunk: 32.0 ±â€¯0.1 vs 32.5 ±â€¯0.1 °C, P < 0.05) measured by infrared thermography. Animals maintained in CLF showed a significant preferential use of shade and a 23% reduction in the frequency of the animals searching for water troughs. It is evident from the study that integrated crop-livestock-forestry systems can be used to provide a more favorable microclimate within grasslands. Thus, beef cattle benefits from the milder environment and exhibits a higher thermal comfort, which favors food production and the rational use of natural resources.


Assuntos
Criação de Animais Domésticos , Temperatura Corporal , Bovinos/fisiologia , Atividade Motora , Árvores , Criação de Animais Domésticos/métodos , Animais , Brasil , Feminino , Árvores/crescimento & desenvolvimento
6.
J Therm Biol ; 79: 103-111, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30612670

RESUMO

This study aimed to assess solar radiation transmission and animal thermal comfort indexes in two silvopastoral systems established with different tree arrangements in a tropical region. This study was conducted between 2014 and 2017 in two silvopastoral systems, one composed by an established Urochloa (syn. Brachiaria) decumbens pasture with Brazilian native trees planted in triple rows spaced 17 m apart, and another by an established Urochloa (syn. Brachiaria) brizantha (Hochst ex A. Rich.) Stapf 'BRS Piatã' pasture with Eucalyptus urograndis (clone GG100) trees arranged in single rows spaced 15 m apart. In these systems and in a full-sun pasture, photosynthetically active radiation transmission, air temperature, relative humidity, black globe temperature, and wind speed were measured. These variables were used to calculate black globe temperature and humidity index (BGHI) and radiant thermal load (RTL). Higher animal thermal comfort was observed in the silvopastoral systems due to changes in the microclimate induced by the trees; notably, a decrease in solar radiation transmission. Fewer hours of potential animal thermal stress (BGHI>79) were observed in the silvopastoral systems than under the full-sun conditions, with differences up to 3 h per day. The silvopastoral systems presented lower radiant thermal load than the full-sun pasture with differences up to 22% achieved. The assessed silvopastoral systems may help livestock adapt to climate change, since they achieved the limit of BGHI considered to cause stress to animals following an increase of 2.2 °C in air temperature, compared with full-sun pastures.


Assuntos
Pradaria , Gado/fisiologia , Microclima , Termotolerância , Árvores/fisiologia , Agricultura/métodos , Animais , Mudança Climática , Transtornos de Estresse por Calor/prevenção & controle , Transtornos de Estresse por Calor/veterinária , Temperatura Alta
7.
Int J Biometeorol ; 62(9): 1575-1586, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29732473

RESUMO

It is believed that increased livestock production is limited by tropical climate. Thermal imbalance in bulls can lead to hyperthermia and alter testicular metabolism, causing subfertility or infertility. Therefore, the thermoregulation of composite Canchim bulls (5/8 Charolais × 3/8 Zebu) raised in tropical climate as well as their consequences in the physiological, hematological, hormonal, and andrological parameters were evaluated monthly. The bulls (n = 18; 30.0 ± 1.5 months; 503.8 ± 23.0 kg) were kept on pasture, in a single group, from August 2015 to March 2016, comprising the winter, spring, and summer seasons. Biometeorological variables were continuously monitored, and the Temperature and Humidity Index (THI) was calculated. A greater thermal challenge occurred in spring and summer (THI ≥ 72.0). Nevertheless, the bulls exhibited normothermia (38.6 to 38.9 °C) in these seasons. The cortisol did not vary between seasons (7.0 vs. 8.7 vs. 6.8 ng/mL; P > 0.05) and remained within the physiological patterns. Independent of the seasons, stress leukogram was also not observed, refuting the incidence of acute or chronic thermal stress. It is noteworthy that T3 and testosterone increased (P < 0.0001, P < 0.05) in spring and summer, the time that coincides with the breeding season, when there is increased metabolic requirement from the bulls. The progressive thermal challenge increase did not affect the scrotal thermoregulatory capacity, and in general, scrotal temperature remained at 5.2 °C below the internal body temperature. In summer, there was a 5% reduction in the minor sperm defects (P < 0.05) and DNA fragmentation in 2.4% of spermatozoa, a compatible value for high fertility bulls. The results show that the studied composite bulls can be considered as climatically adapted and constitute a viable alternative to be used in production systems in a tropical climate, even if the breeding seasons occur during the most critical thermal condition periods of the year.


Assuntos
Regulação da Temperatura Corporal , Bovinos , Fertilidade , Clima Tropical , Animais , Umidade , Masculino , Carne Vermelha , Estações do Ano , Espermatozoides
8.
J Therm Biol ; 69: 302-310, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29037398

RESUMO

Climate change has intensified the frequency of heat waves in the world, thereby exposing farm animals to stressful conditions. For better productive performance it is important to identify the most resilient genotypes. Thus, our objective was to evaluate the thermoregulatory responses of rams of tropical indigenous (Morada Nova and Santa Inês) and exotic breeds (Dorper and Texel), by monitoring the environmental and physiological indicators related to heat tolerance. The experiment was carried out in a tropical climate region (Cwa), in Brazil, for twelve months, which comprised spring, summer, autumn and winter. Thirty-three rams were divided into groups: Morada Nova (MN; n=8, red-coat), Santa Inês (SI; n=9, black-coat), Dorper (DO; n=8, white-coat) and Texel (TX; n=8, white-coat). The microclimatic variables were monitored, and the THI and BGHI comfort indices were calculated. Coat thickness and body surface temperatures were measured monthly, and serum triiodothyronine-T3 measurements and complete blood tests were performed. The physiological variables were evaluated every fifteen days and skin micro-biopsies were performed in the summer and winter for histological evaluation. During the warmer seasons, the THI and BGHI reached values that indicated thermal discomfort. TX showed higher coat thickness throughout the year, increased physiological variables related to thermolysis, and reduced T3 (P < 0.05). The internal temperature was permanently lower in the MN, SI and DO (P < 0.05). The body surface temperatures were affected by the coat characteristics and wool length. Hematological parameters varied in the seasons with the highest thermal conditions (P < 0.05). The MN showed larger sweat glands, while the area occupied by the sweat glands was higher in the SI. The DO showed higher hair density in the summer and winter (P < 0.05). The results indicated that the MN, SI and DO breeds overcome the thermal challenge more easily throughout the seasons due to specific adaptive morphological and physiological characteristics.


Assuntos
Regulação da Temperatura Corporal , Ovinos/fisiologia , Termotolerância , Animais , Temperatura Corporal , Mudança Climática , Resposta ao Choque Térmico , Masculino , Estações do Ano , Ovinos/anatomia & histologia , Ovinos/sangue , Termografia , Tri-Iodotironina/sangue , Clima Tropical
9.
Int J Biometeorol ; 61(10): 1819-1829, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28497170

RESUMO

This study aimed to assess the capacity of Morada Nova (MN) and Santa Inês (SIN) rams to maintain body and testicular homeothermy under thermal challenge. For 5 days in the summer, 16 males (SIN = 7 and MN = 9) underwent a heat tolerance test, i.e., period 1-animals maintained in the shade (11 to 12 h); period 2-animals exposed to sunlight (12 to 13 h); and period 3-animals returned to the shade (13 to 14 h). The respiratory rate, heart rate, rectal temperature, and infrared surface temperatures (IRT) of the trunk, back, eyeball, and testicles were assessed in each period. The index of capacity of tolerance to insolation (ICTI), which indicates the animals' level of adaptability, was calculated for each animal. Semen quality and testicular parenchyma integrity were assessed before and after the thermal challenge. Statistical analyses were performed at 5% significance. In period 1, the variables had baseline values for both genotypes. In period 2, the variables involved in thermolysis significantly increased (P < 0.05), which matches a thermal discomfort situation. In period 3, the variables returned to baseline values and some values were lower than those in period 1. Semen quality and testicular parenchyma integrity suffered no negative effects with the thermal challenge. IRT ocular and IRT testicular were positively correlated (P < 0.05). It is concluded that MN and SIN rams had efficient thermolytic mechanisms that favor preserving gonadal functionality. The animals were considered resilient to a thermal challenge. In addition, infrared thermography was an efficient tool to verify body and testicular thermoregulation.


Assuntos
Análise do Sêmen , Ovinos/fisiologia , Termotolerância , Animais , Temperatura Corporal , Brasil , Frequência Cardíaca , Temperatura Alta , Masculino , Microclima , Taxa Respiratória , Testículo/fisiologia , Clima Tropical
10.
Int J Biometeorol ; 58(7): 1479-87, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24221392

RESUMO

The objective of this work was to develop and evaluate agrometeorological models to simulate the production of Guineagrass. For this purpose, we used forage yield from 54 growing periods between December 2004-January 2007 and April 2010-March 2012 in irrigated and non-irrigated pastures in São Carlos, São Paulo state, Brazil (latitude 21°57'42″ S, longitude 47°50'28″ W and altitude 860 m). Initially we performed linear regressions between the agrometeorological variables and the average dry matter accumulation rate for irrigated conditions. Then we determined the effect of soil water availability on the relative forage yield considering irrigated and non-irrigated pastures, by means of segmented linear regression among water balance and relative production variables (dry matter accumulation rates with and without irrigation). The models generated were evaluated with independent data related to 21 growing periods without irrigation in the same location, from eight growing periods in 2000 and 13 growing periods between December 2004-January 2007 and April 2010-March 2012. The results obtained show the satisfactory predictive capacity of the agrometeorological models under irrigated conditions based on univariate regression (mean temperature, minimum temperature and potential evapotranspiration or degreedays) or multivariate regression. The response of irrigation on production was well correlated with the climatological water balance variables (ratio between actual and potential evapotranspiration or between actual and maximum soil water storage). The models that performed best for estimating Guineagrass yield without irrigation were based on minimum temperature corrected by relative soil water storage, determined by the ratio between the actual soil water storage and the soil water holding capacity.irrigation in the same location, in 2000, 2010 and 2011. The results obtained show the satisfactory predictive capacity of the agrometeorological models under irrigated conditions based on univariate regression (mean temperature, potential evapotranspiration or degree-days) or multivariate regression. The response of irrigation on production was well correlated with the climatological water balance variables (ratio between actual and potential evapotranspiration or between actual and maximum soil water storage). The models that performed best for estimating Guineagrass yield without irrigation were based on degree-days corrected by the water deficit factor.


Assuntos
Modelos Teóricos , Panicum/crescimento & desenvolvimento , Agricultura/métodos , Brasil , Panicum/metabolismo , Transpiração Vegetal , Reprodutibilidade dos Testes , Solo/química , Luz Solar , Temperatura , Água/análise , Tempo (Meteorologia)
11.
Int J Biometeorol ; 56(5): 843-51, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21866379

RESUMO

The objective of this study was to determine the harvest period of coffee fruits based on the relationship between agrometeorological parameters and sucrose accumulation in the seeds. Over the crop years 2004/2005 and 2006/2007, from 150 days after flowering (DAF) onwards, samples of 50 fruits of cultivars Mundo Novo IAC 376-4, Obatã IAC 1669-20 and Catuaí Vermelho IAC 144 were collected from coffee trees located in Campinas, Brazil. The endosperm of the fruits was freeze-dried, ground and analyzed for sucrose content by high-performance liquid chromatography. A weather station provided data to calculate the accumulated growing degree-day (GDD) units, and the reference (ET(o)) and actual (ET(r)) evapotranspiration rates. The results showed that the highest rates of sucrose accumulation occurred at the transition from the cane-green to the cherry phenological stage. Models for the estimation of sucrose content during maturation based on meteorological variables exhibited similar or better performance than the DAF variable, with better results for the variables GDD and ET(o). The Mundo Novo cultivar reached the highest sucrose level in the endosperm after 2,790 GDD, while cultivar Catuaí attained its maximum sucrose concentration after the accumulated evapotranspiration rate has reached a value of 870 mm. As for cultivar Obatã, the maximum sucrose concentration was predicted with the same degree of accuracy using any of the parameters investigated. For the Obatã cultivar, the values of the variables calculated for the maximum sucrose concentration to be reached were 249 DAF, 3,090 GDD, 1,020 ET(o) and 900 ET(r).


Assuntos
Coffea/química , Frutas/química , Modelos Teóricos , Sacarose/análise , Clima , Coffea/fisiologia , Frutas/fisiologia , Transpiração Vegetal
12.
Ciênc. rural ; 40(6): 1257-1263, jun. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-554630

RESUMO

Medições microclimáticas (radiação fotossinteticamente ativa - RFA, temperatura do ar, umidade relativa do ar e velocidade do vento) foram realizadas em um cultivo de café Conilon (Coffea canephora Pierre) cultivado a pleno sol e arborizado com nogueira macadâmia (Macadamia integrifolia Maiden & Betche), no Município de São Mateus, Espírito Santo (ES) (18°43'S; 39°54'W; 39m), durante o período de setembro de 2008 a junho de 2009, com o objetivo de apresentar os efeitos do cultivo arborizado no microclima. Os resultados obtidos mostraram diferenças na transmissividade à RFA dentro do sistema arborizado em relação ao pleno sol, com variações de 18 a 88 por cento e de 17 a 87 por cento quando comparados em dois episódios de amostragem. A transmissividade média da RFA provocada pelas árvores de macadâmia variou de 65 a 59 por cento durante as duas épocas de amostragem. Com relação à velocidade do vento, ocorreu uma redução média de 72 por cento em sua incidência no cultivo arborizado. As diferenças na transmissividade de radiação e na incidência de ventos proporcionaram diferentes regimes de temperatura do ar e umidade relativa do ar, com maior efeito sobre os valores diurnos e no ponto de amostragem próximo ao renque de macadâmias, em que a média da temperatura máxima do ar foi até 2,2°C inferior ao cultivo a pleno sol.


Microclimatic measurements (photosynthetically active radiation - PAR, temperature and relative humidity of air and wind speed) were made in a Conilon coffee crop (Coffea canephora Pierre), grown in two different conditions: shaded by macadamia nut trees (Macadamia integrifolia Maiden & Betche) and unshaded. The experiment was carried out at Sâo Mateus, Espirito Santo State, Brazil (18°43'S; 39°54'W; 39m), between September 2008 and June 2009, aiming to show the effects of shading crop system into the microclimate. The obtained results had inside shown differences in the transmission of PAR in the shaded crop, with variations of 18 to 88 percent and 17 to 87 percent when compared the two sampling episodes . The average transmission of PAR caused by macadamia nut trees varied of 65 to 59 percent during the sampling episodes. The wind speed was reduced by 72 percent at the shaded crop. The differences in the transmission of PAR and the incidence of winds produced different values of temperature and relative humidity of the air with the greatest effect during day-light values period and at the sampling nearest point to macadamias nut trees, where the average maximum temperature was up to 2.2°C lower than the unshaded ones.

13.
Ciênc. rural ; 39(3): 711-717, maio-jun. 2009. ilus
Artigo em Português | LILACS | ID: lil-514061

RESUMO

O objetivo deste trabalho foi avaliar o efeito do ano agrícola sobre os atributos fenológicos e agronômicos em diferentes cultivares de cafeeiro arábica. Os atributos fenológicos determinados foram estádios de frutificação, de gema dormente até fruto seco e duração do ciclo. Como atributos agronômicos, foram avaliados o rendimento, a produtividade, os tipos e o tamanho de grãos. O período entre antese até fase chumbinho não variou entre as cultivares para o ano agrícola 2004/2005, já para o ano agrícola seguinte a cultivar 'Icatu Precoce' apresentou antecipação da fase chumbinho, e a cultivar 'Obatã' atrasou o início do ciclo fenológico em relação às demais cultivares estudadas. A duração do ciclo variou com o ano agrícola, o que possibilitou a confirmação da influência dos efeitos ambientais nessa característica. Os atributos agronômicos (produtividade, rendimento, tipo e tamanho de grãos), independentemente das cultivares, também variaram com o ano agrícola.


The aim of this study was to evaluate cultivars of Coffea arabica on the basic of phenology and agronomic attributes a function of the year of production. The phenological attributes were evaluated regarding phenology and percentage of cherry fruits at harvesting time. Agronomic traits evaluated included productivity and outturn, type of seeds and grain size. The period between the blooms till the fruits at the beginning of growth did not vary among the coffee trees in the year of production 2004/2005. While in the following year the Icatu Precoce cultivar presented anticipation of the fruits at the beginning of growth and the 'Obatã' cultivar delayed the beginning of the phenological cycle due to the other cultivars studied. The duration of each cycle varied with the year of production and then all the coffee trees in this study could be differentiated on the timing of maturation (early, middle and late). The agronomic attributes (productivity, outturn, type and size of grains), regardless the different cultivars of coffee also varied with the year of production.

14.
Ciênc. agrotec., (Impr.) ; 32(6): 1781-1786, nov.-dez. 2008. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-508577

RESUMO

Foram determinados para o café arábica cv. Mundo Novo, a temperatura base inferior e a soma térmica, expressa em grausdia, além do acúmulo de evapotranspiração de referência (ETo) e real (ETr), para o subperíodo florescimento-colheita, utilizando-se dados fenológicos de cultivos dos anos de 1971 a 2004. Foi proposto ainda um fator de correção para o cálculo de graus-dia em função da disponibilidade hídrica nos oito primeiros decêndios após o florescimento. Os valores de temperatura-base e soma térmica obtidos foram de 10,2ºC e 2887 graus-dia e 10,5ºC e 2761 graus-dia, quando determinados sem e com correção pelo fator hídrico, respectivamente. O acúmulo médio de Eto para o subperíodo do florescimento à colheita foi de 761mm e para Etr 689 mm; quando se levou em consideração o acúmulo de ETr apenas no início do desenvolvimento dos frutos (oito primeiros decêndios), o valor médio foi de 721mm. A utilização de métodos que levaram em consideração a influência da disponibilidade hídrica melhorou a estimativa da temperatura base e a soma térmica no subperíodo do florescimento à colheita do cafeeiro Mundo Novo.


Base temperature and heat requirement, using degree-days were evaluated for coffee cv. Mundo Novo. The sum of reference (ETo) and actual (ETr) evapotranspiration were also determined for the flowering-harvest phenological stage, using coffee phenological data for the growing season from 1971 to 2004. A correction factor was proposed for the degree-days sum related to available water on the first eighty days during the beginning of flowering. The obtained values of base temperature and degree-days requirements were, respectively, 10.2ºC and 2887 degree-days and 10.5ºC and 2761 degree-days when evaluated with and without adjustement for water deficit. The mean value for ETo sum was 761 mm, and for ETr, 689 mm. When considered the sum of ETr during the development of the berries (first 80 days after flowering) was considered the mean values were 721 mm. The correction factor for water deficit improved the determination of base temperature and heat sum for the flowering-harvest stage for Mundo Novo coffee plants.

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