Silvopasture is the intentional integration of trees with forages and livestock. In Blackstone, Virginia a silvopasture management plan was created in a thinned, timber stand seeded with a cool-season forage mixture. Treatment pastures for this study included an open pasture, a thinned pine silvopasture, a thinned hardwood silvopasture, and a cleared and replanted new pine silvopasture. Cattle were introduced in 2017 and rotationally stocked within each pasture according to forage availability. Objectives were to determine the forage availability, forage nutritive value, and the performance of heifers in silvopasture and open pasture systems. Additionally, the new pine silvopasture was grazed to determine the effect of cattle on tree seedlings without protection. Forage availability was affected by date and year and was significantly lower in 2018 (3560 kg ha-1) versus 2017 (5350 kg ha-1). Pre-grazing forage availability was lowest in the pine and hardwood silvopastures in both years (4500 kg ha-1) compared to the open pastures (4920 kg ha-1; p < 0.0001). Date significantly influenced nutritive value, but only had date by treatment interaction in the 2017 grass crude protein and neutral detergent fiber sample. In 2017, the new silvopasture (61% TDN) had greater total digestible nutrients as compared to the open pasture and thinned hardwood silvopasture (57% TDN; p = 0.0292); there was no significant difference (p=0.3733) in total digestible nutrients in 2018 between pastures (58% TDN). In 2017, average daily gains of the heifers were greatest in the silvopastures in June (p = 0.0346). In 2018, average daily gain was lowest among silvopastures later in the summer compared to open pastures and new silvopastures (pJuly = 0.0051; pAugust = 0.0008). Remote temperature loggers were used to collect vaginal temperatures of the heifers over eight days in 2018. Silvopasture heifers had an average core temperature of 39.4 °C from 2-5 PM while heifers in the open pastures had an average temperature of 40.0 °C. A drone with a thermal camera was used to collect external hide temperatures in the morning and afternoon. Heifers in the silvopastures had lower heat loads in the afternoon while animals without shade experienced a 65% greater temperature increase between morning and afternoon when compared to the shaded animals. Silvopastures provide an opportunity to improve the welfare of grazing livestock in the summer, while improving the overall productivity and efficiency of land. Tree seedlings that were planted into pasture to create a new silvopasture experienced a 16% mortality rate while over 75% of tree seedlings had less than 50% damage after two years and would continue to produce trees with future economic and shade value. Future research should focus on how to implement silvopasture as part of a holistic grazing and management plan while continuing to evaluate cattle, forage, and tree response to silvopastures over multiple years. / Master of Science / Silvopasture is the intentional integration of trees with forages and livestock. In Blackstone, Virginia a silvopasture management plan was created in a thinned, timber stand seeded with a cool-season forage mixture. Treatment pastures for this study included an open pasture, a thinned pine silvopasture, a thinned hardwood silvopasture, and a cleared and replanted new pine silvopasture. Cattle were introduced in 2017 and rotationally stocked within each pasture according to forage availability. Objectives were to determine the forage availability, forage nutritive value, and the performance of heifers in silvopasture and open pasture systems. Additionally, the new pine silvopasture was grazed to determine the effect of cattle on tree seedlings without protection. Forage availability was lowest in the pine and hardwood silvopastures in both years compared to the open pastures. Nutritive value of forages was most greatly influenced by time rather than tree presence. In 2017, average daily gains of the heifers were greatest in the silvopastures in June. In 2018, average daily gain was lowest among silvopastures later in the summer compared to open pastures and new silvopastures. Internal and external body temperatures of heifers during the afternoon decreased with increasing shade availability with the greatest internal body temperatures occurring in unshaded animals. Silvopastures provide an opportunity to improve the welfare of grazing livestock in the summer, while improving the overall productivity and efficiency of land. Tree seedlings experienced minimal damage by cattle and would continue to produce trees with future economic and shade value. Future research should focus on how to implement silvopasture as part of a holistic grazing and management plan while continuing to evaluate cattle, forage, and tree response to silvopastures over multiple years.

The theory that fruit abscission may be the result of a reduction in metabolites available to the young fruit was addressed by this study. Shade cloth or terbacil, a photosynthetic inhibitor, were applied to limbs and whole trees to examine the influence of treatment and time of application on fruit nonstructural carbohydrates and abscission. 'Stayman' apple limbs shaded with 92% shade material from 5-15, 10-20, 15-25, 20-30, and 25-35 days after full bloom (April 22) had lower fruit retention than unshaded controls on 11 June. On 18 June, fruit diameter was greater on limbs shaded between 5-25 days after full bloom (DAFB) than on unshaded limbs. At 15, 20, 25, and 30 DAFB, fruit from limbs shaded for 10 days had lower total nonstructural carbohydrates (TNC), total sugars, and reducing sugars (% dry wt) than fruit from limbs shaded for 0 or 5 days. Terbacil (3-tert-butyl-5-chloro-6-methyluracil) was applied at 0, 50, 100, and 200 ppm to whole nine-year-old 'Redchief Delicious' apple trees at 15 DAFB. Terbacil markedly inhibited Pn; recovery occurred by 9 and 26 DAA for the 50 and 100 ppm rates, respectively. Phytotoxicity prevented the determination of Pn in the 200 ppm treated trees. Fruit dry weight, TNC, total sugars, and reducing sugars (% dry wt and mg/fruit) declined with increasing rates of terbacil. Total fruit abscission was observed 12 DAA for the 100 and 200 ppm treatments, while the 0 and 50 ppm applications retained 4.6 and 1.4 fruit per cm² limb cross sectional area (LCSA) at 35 DAA, respectively. Compared to the control, 50 ppm terbacil decreased fruit number and weight at harvest, but increased fruit weight. Terbacil at 75 ppm and 92% shade material were applied to whole, 3-year-old 'Redchief Delicious' trees at 18, 23, and 28 DAFB. Generally, fruit dry weight, total sugars, and reducing sugars were lowered by both shade and terbacil treatments. In most cases, fruit from shaded trees were lower in dry weight and measured nonstructural carbohydrates than fruit from terbacil-treated trees after 5 or 10 days of treatment. Shading for 5 or 10 days resulted in total fruit drop. Terbacil at 75 ppm resulted in 0.8 as opposed to 2.9 fruit per cm² LCSA on the controls at 54 DAFB. / M.S.

Exotic species often invade new areas and displace native species. The problems associated with such invasions are well known, but for many exotic species, experimental work has not yet been done to predict which, and under what conditions they may become a problem. Two greenhouse experiments were devised to investigate the plasticity, shade tolerance, and phenotypic differences of full-siblings from 3 populations of Cardamine impatiens, a Eurasian species potentially invasive in North America. Potted plants were subjected to 0, 54, 76, or 91% shade created by neutral density shade cloth application. In addition, the impact of a cold pre-treatment of seedlings on the growth and reproductive output of C. impatiens plants was examined. In our first experiment, we subjected Cardamine impatiens to non-shaded cages, 54%, or 76% shade intensity. Plants died very quickly, so LD50 data were used as a relative measure of fitness, and relative growth indices were calculated over time. Other relative measures of fitness included canopy area, leaf area, number of leaves, number of leaves per canopy area, and final plant weight. Plants in cages with no shade treatment grew faster than those in cages with shade cloth and final plant weight decreased as shade treatment percentage increased. In each population, the number of leaves increased over time and the number of leaves per canopy area decreased over time under shade treatments. Our second experiment involved the application of 54%, 76%, and 91% shade intensity. The additional shade treatment of 91% was applied to determine the extent of plant tolerance and plasticity in response to light reduction. Due to high plant mortality in our first experiment, we treated Cardamine impatiens with a 4 week cold period prior to treatment, which simulates its biennial growth form in its natural western Virginia region habitat. Since this second experiment took place later in the year, day length was extended to more accurately duplicate the conditions during the first experiment. LD50 calculations were not necessary, and 7 of the 135 plants produced seed. Relative measures of fitness included canopy area, leaf area, number of leaves, number of leaves per canopy area, and final plant weights. As in experiment one, the number of leaves per plant increased over time, final plant weight decreased as shade treatment increased, and the number of leaves per canopy area decreased as shade treatment increased. From these two experiments, we determined that Cardamine impatiens is a species that exhibits phenotypic plasticity and therefore may pose a threat as an invasive species. C. impatiens is able to grow and exhibit plasticity of plant architecture under the conditions of very low light. The number of leaves per canopy area decreased as shade increased, suggesting that C. impatiens is highly adaptable to low light conditions, and therefore may be exhibiting phenotypic plasticity by reallocating its resources by producing fewer leaves while maintaining canopy area. This data along with other C. impatiens traits such as high levels needed for seed production, its persistence in seed banks, along with a lack of known major enemies, indicates that they have a great capacity to invade a wide variety of habitats. We also determined that a cold treatment is necessary in order for C. impatiens to obtain optimal growth and reproduction. / Master of Science

No description available.

No description available.

Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Jack D. Fry / ‘Meyer’ zoysiagrass (Zoysia japonica Steud.) has been the predominant cultivar in the transition zone of the U.S. since its release in 1952, primarily because of its good freezing tolerance. However, it is slow to establish and recover after sod harvest, and has poor shade tolerance. I evaluated ‘Meyer’, some commonly used cultivars, and 18 progeny from crosses of ‘Emerald’ (Z. japonica × Z. tenuifolia Willd. ex Thiele) × Z. japonica or Z. matrella (L.) Merr. × Z. japonica for stolon growth characteristics; sod tensile strength and recovery after harvest; shade resistance; freezing tolerance and its relationship to autumn color retention; and the potential influence of dehydrin and chitinase gene expression in freezing tolerance. After planting vegetative plugs, rates of stolon initiation (r = 0.66 in 2007, r = 0.94 in 2008) and elongation (r = 0.66 in 2007, r = 0.53 in 2008) were positively correlated (P < 0.05) with zoysiagrass coverage. At 60 days after sod harvest, recovery growth coverage ranged from 17% to 97% and a progeny from Z. matrella × Meyer (97% coverage) demonstrated superior sod recovery growth to Meyer (38% coverage). Under 68% silver maple (Acer saccharinum L.) tree shade, stolon number was reduced 38 to 95% and stolon length 9 to 70% compared to turf in full sun. Several progeny from crosses between Emerald or a Z. matrella x Z. japonica produced more and/or longer stolons than Meyer in the shade, suggesting potential for increased shade tolerance. Autumn color in October and November, 2007 was positively correlated (r = 0.44 and r = 0.58, P < 0.01) with the lethal temperature killing 50% of tillers (LT50) in December, 2007. All grasses except Cavalier and one progeny were equivalent to Meyer in freezing tolerance with LT50s ranging from -0.2 to -12.2 oC. Dehydrin-like (11.9, 23, 44.3, and 66.3 kDa) and chitinase (26.9 kDa) gene expression increased with cold acclimation and was similar among all grasses. In general, some new zoysiagrass progeny exhibited superior growth and/or stress tolerances compared to Meyer, which bodes well for potential release of a new cultivar for use in the transition zone.

Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Dale J. Bremer / Jack D. Fry / Researchers and practitioners can use numerous techniques to measure or estimate evapotranspiration (ET) from turfgrass but little is known about how they compare to ET using standard lysimeters. An investigation was conducted to compare measurements of ET from lysimeters (LYS[subscript]E[subscript]T) with ET estimates from the FAO56 Penman-Monteith (PM[subscript]E[subscript]T) and Priestley-Taylor (PT[subscript]E[subscript]T) empirical models, atmometers (AT[subscript]E[subscript]T), eddy covariance (EC[subscript]E[subscript]T), and a canopy stomatal conductance model that estimates transpiration (COND[subscript]T). Methods were compared at the same site during the 2010, 2011, and 2012 growing seasons. Overall, PT[subscript]E[subscript]T and EC[subscript]E[subscript]T were not different from LYS[subscript]E[subscript]T, whereas PM[subscript]E[subscript]T, AT[subscript]E[subscript]T, and COND[subscript]T, increasingly underestimated LYS[subscript]E[subscript]T. Differences exist among ET measurement techniques and one should employ the technique that best fits their situation. An atmometer is an inexpensive tool that can be used to measure turfgrass ET within microclimates, such as those typically found in an urban home lawn. An investigation was conducted to compare AT[subscript]E[subscript]T estimates with PM[subscript]E[subscript]T estimates within a number of lawn microclimates. Home lawns in Manhattan and Wichita, KS, were selected for study during the growing seasons of 2010 and 2011. Open sward AT[subscript]E[subscript]T was 4.73 mm d[superscript]-[superscript]1, whereas PM[subscript]E[subscript]T was 5.48 mm d[superscript]-[superscript]1. Within microclimates, AT[subscript]E[subscript]T was 3.94 mm d[superscript]-[superscript]1 and PM[subscript]E[subscript]T 3.23 mm d[superscript]-[superscript]1. Atmometers can provide practitioners with reliable estimates of PM[subscript]E[subscript]T within microclimates. Zoysiagrass (Zoysia spp.) is a common turfgrass used on home lawns and golf courses. However, poor shade tolerance and cold hardiness have limited its use in the transition zone. A study was conducted to determine changes and differences in growth and physiology among selected Zoysia over a three-year period (2010-2012) in the transition zone. The genotypes were 'Emerald' [Z. japonica × Z. pacifica], 'Zorro' [Z. matrella], 'Meyer' and Chinese Common [Z. japonica], and experimental progeny Exp1 [Z. matrella × Z. japonica], and Exp2 and Exp3 [(Z. japonica × Z. pacifica) × Z. japonica]. 'Zorro' and 'Emerald' experienced winter injury. 'Meyer', Chinese Common, and Exp1 showed poor performance over the three-years. The Exp2 and Exp3 progeny, maintained high percent cover, visual quality, and tiller density, and may provide practitioners more shade-tolerant cultivar choices in the transition zone.

O presente trabalho envolve duas espécies de palmeiras produtoras de palmito comestível: o açaí (Euterpe oleracea) e a palmeira real australiana (Archontophoenix alexandrae) tendo por objetivo: medir os caracteres agronômicos, mensurar os caracteres fisiológicos em 3 ambientes de luminosidade, estudar a anatomia dos palmiteiros e avaliar o comportamento das duas espécies em vista de direcionar o produtor, em qual melhor ambiente luminoso deve-se plantar os palmiteiros. A hipótese assumida foi: o crescimento e desenvolvimento em condições de radiação diferente, acarretam em modificações fisiológicas e anatômicas que afetam o desempenho dos palmiteiros e sua produção. O experimento foi realizado em dois locais: Piracicaba (22o42\'11\" latitude Sul e 47o38\'09\" longitude Oeste, altitude 531 m), onde estava cultivado o açaí e em Pirassununga (latitude 21º59\'46\" Sul, longitude 47º25\'33\" Oeste, e altitude 627 m), onde se encontrava a palmeira real australiana, nos dois cultivos as plantas se encontravam com 36 meses de plantio a campo, estabeleceu-se 3 tratamentos: Pleno sol (PS), Meia sombra (MS) e Sombra (S), onde foram realizadas duas medições nos quais foram avaliados: caracteres agronômicos e fisiológicos, obtidos através do IRGA. Para esses caracteres uma análise preliminar dos dados foi desenvolvida para caracterizar a população amostrada. Calculou-se a média, o desvio padrão, o coeficiente de variação e os valores máximo e mínimo. Empregou-se o teste de Tukey adotando-se nível de 5 % de probabilidade. As análises foram complementadas com o estudo de correlações lineares, além das análises histológica e ultraestrutural, o delineamento empregado foi o inteiramente casualizado. Nos resultados observados em açaí, para o caráter diâmetro tanto o valor do diâmetro da mãe, como nos seus perfilhos (1, 2 e 3), o ambiente MS se mostrou mais adequado para a obtenção de um diâmetro maior. O número de perfilho (CV 32%) para o tratamento PS foi de 7,67, na MS 9,5 e na sombra 5,67, mostrando que existe uma maior tendência em se encontrar maior número de perfilhos em ambientes sombreados. Dentre os caracteres relacionados, os que apresentaram maior variabilidade foram o número de perfilho e número de folhas, com CV variando entre 32 a 29%. Adotando-se o teste de Tukey não houve diferença significativa nos parâmetros estudados, mostrando que existe uma tendência em estabilizar as medidas de caráter agronômico, independente de sua luminosidade. Para os caracteres fisiológicos ao longo do período experimental não houve diferença entre as respostas da fotossíntese, condutância estomática e transpiração. Para os resultados da palmeira real australiana obtidos, o caráter número de folhas (CV 7%), observa-se que o número de indivíduos avaliados (40 plantas/ tratamento) foram suficientes para constituir uma amostra representativa da população, parecendo haver pouca variabilidade para ser explorada, isto pode ser devido à base genética restrita da mesma. Os coeficientes de variação estudados variaram de 7 % (número de folhas) a 19% (diâmetro médio da planta). Para os caracteres fisiológicos houve diferença significativa entre os caracteres. Na análise histológica e ultraestrutural houve diferença mostrando que plantas cultivadas a pleno sol possuem maior tamanho de parênquima paliçádico e maior número de estômatos. / The present work involves two species of producing heart of palm: assai palm (Euterpe oleracea) and the king palm (Archontophoenix alexandrae) with objective: to measure the agronomic and physiological characters, in 3 environments of luminosity, to study the anatomy of the palm and to evaluate the behavior of the two species in sight to direct the producer, in better luminous surrounding which must be planted the species. The assumed hypothesis was: the growth and development in conditions of different radiation, cause physiological and anatomical modifications that affect the performance of the plants and its production. The experiments were carried out in two places: the assai palm was carried out in Piracicaba (22o42\'11\"S and 47o38\'09\"W, 531 altitude m), and king palm was in Pirassununga (21º59\'46\"S, 47º25\'33\" W, and 627 altitude m). The crops were with 36 months of plantation in the field, there were established 3 treatments: full sun (PS), half shade (MS) and shade (S), in the plants populations there were made agronomic and physiological evaluations. For these characters a preliminary analysis of the data was developed to characterize the population used. It was calculated average, standard desviation and the coefficient of variation and the values maximum and minimum. The Tukey test was used adopting 5 % of mistake probability. The analyses had been complemented with the study of linear correlations, beyond the analyses histological and ultrastructural, the completely randomized delineation was used to evaluate the results. In the results observed in assai palm, for the character diameter of the trunk and palm girth (1, 2 and 3), the environment MS showed more adequate for a bigger diameter. The number of palm girth (CV 32%) for treatment PS was of 7,67, in MS 9,5 and shade 5,67, showing that it exists a bigger trend to find more number of girth in environments with more shade. Among the related characters, the ones that had presented greater variability had been the number of palm girth and leaf number, with CV 32 29%. Adopting the Tukey test it did not have significant difference in the studied parameters, showing that a trend in stabilizing the measures of agronomic character exists, independent of its luminosity. For the physiological characters during the experimental period it did not have difference enters the answers of the photosynthesis, stomatal conductance and transpiration. For the results of the king palm gotten the character leaf number (CV 7%), it is observed that the number of evaluated individuals (40 plants treatment) had been enough to constitute a representative sample of the population, having seemed to have little variability to be explored, this can have the restricted genetic base of the same one. The studied coefficients of variation had varied of 7 % (leaf number) 19% (average diameter of the plant). For the physiological characters it had significant difference between the characters. In the histological and ultrastructural analysis it had difference showing that cultivated plants at full sun environment have bigger parenchyma and bigger number of stomata.

O objetivo do estudo foi a avaliação dos mecanismos termorreguladores, baseada numa abordagem temporal em função de diferentes armazenamentos de calor, proporcionados por diferentes tipos de ambientes térmicos (com e sem radiação solar). Foram utilizadas 12 búfalas da raça Mediterrânea que foram submetidas a quatro experimentos durante o verão de 2010 a 2012 delineados para o comprimento dos objetivos específicos. Nos vários experimentos os parâmetros meteorológicos registrados foram: temperatura de bulbo seco, temperatura de bulbo úmido, umidade relativa do ar, velocidade do vento e temperatura de globo negro. Os parâmetros fisiológicos avaliados foram: temperatura retal, temperatura da base da cauda, temperatura da epiderme, temperatura de superfície do pelame, frequência respiratória e taxa de sudação. As análises estatísticas foram realizadas com auxílio do programa Statistical Analysis System, versão 9.1.3 (SAS Institute Inc., Cary, NC, USA), utilizando-se os procedimentos PROC MIXED. No experimento 1 que visou verificar as reações termorreguladoras ao ambiente aquecido em unidade biometeorológica, o aumento da temperatura do ar em ambiente controlado influenciou todas as variáveis fisiológicas ao longo do dia (P&lt;0,01). O incremento na taxa de sudação durante o período de estresse térmico determinou a depleção na concentração plasmática de potássio (P=0,0051). No experimento 2que avaliou as reações termorreguladoras na presença de radiação solar direta averiguamos que houve influência da exposição ao sol sobre todas as variáveis fisiológicas ao longo do dia (P&lt;0,01). O gradiente térmico favorável no período noturno atenuou os efeitos do estresse térmico não constatando o efeito da exposição a radiação solar direta sobre os constituintes sanguíneos. No experimento 3que objetivou quantificar a velocidade de aquisição de calor ao sol comparando-a posteriormente com a velocidade de dissipação do calor à sombra, constatamos que a exposição por uma hora ao sol incrementou a frequência respiratória em 189,24 % e a temperatura retal em 1,46 %, após o retorno a sombra, por uma hora, verificamos uma redução de 191,75 % e 0,57 %, respectivamente. No experimento 4avaliamos a dinâmica da termólise evaporativa e o balanço térmico de radiação e convecção em condições de radiação solar direta. À medida que reduz a temperatura radiante média, os animais passam a perder o calor armazenado por radiação, reduzem as perdas por polipnéia térmica ao passo que as perdas por sudação permanecem altas. / The aim of the study was to evaluate the thermoregulatory mechanisms, based on a temporal approach, in relation to different heat storages provided by different types of thermal environments (with and without solar radiation). Twelve Mediterranean buffalo heifers were submitted to four experiments during the summer of 2010 to 2012 outlined to achieve specific objectives. Environmental parameters dry bulb temperature; wet bulb temperature; relative humidity; winds speed and black globe temperature were measured. Physiological parameters rectal temperature; base of tail temperature; skin temperature; hair coat surface temperature; respiratory rate and sweating rate were measured. The statistical analysis were done with the assistance of the Statistical Analysis System, version9.1.3(SAS Institute Inc., Cary, NC, USA), using procedures UNIVARIATE,CORR, GLM and MIXED. The first experiment aimed to verify the thermoregulatory reactions of the warm environment in the climatic chamber. Increasing the air temperature in a controlled environment influenced all physiological variables throughout the day (P&lt;0,01). The increase in the sweating rate during heat stress led to the depletion of plasma potassium (P=0,0051). In experiment 2, which assessed the thermoregulatory reactions in the presence of direct solar radiation, it was observed the influence of sun exposure on all physiological variables throughout the day (P&lt;0.01). The favorable thermal gradient at night attenuated the effects of heat stress without identifying the effect of direct sun exposure on blood constituents. In experiment 3, that aimed to measure the heat acquisition rate under the sun subsequently comparing it with the speed of heat dissipation under the shade, it was observed that one hour exposure to the sun increased respiratory rate at 189,24 % and rectal temperature at 1,46 %. After returning the shade for one hour, it was found reductions of 191,75 % and 0,57 %, respectively. The Experiment 4 evaluated the dynamics of evaporative thermolysis and thermal balance of radiation and convection under conditions of direct solar radiation. Reducing the mean radiant temperature, the animals started to lose the stored heat by radiation, reduced losses by thermal polipneia while the losses by sweating remain high.

O presente trabalho envolve duas espécies de palmeiras produtoras de palmito comestível: o açaí (Euterpe oleracea) e a palmeira real australiana (Archontophoenix alexandrae) tendo por objetivo: medir os caracteres agronômicos, mensurar os caracteres fisiológicos em 3 ambientes de luminosidade, estudar a anatomia dos palmiteiros e avaliar o comportamento das duas espécies em vista de direcionar o produtor, em qual melhor ambiente luminoso deve-se plantar os palmiteiros. A hipótese assumida foi: o crescimento e desenvolvimento em condições de radiação diferente, acarretam em modificações fisiológicas e anatômicas que afetam o desempenho dos palmiteiros e sua produção. O experimento foi realizado em dois locais: Piracicaba (22o42\'11\" latitude Sul e 47o38\'09\" longitude Oeste, altitude 531 m), onde estava cultivado o açaí e em Pirassununga (latitude 21º59\'46\" Sul, longitude 47º25\'33\" Oeste, e altitude 627 m), onde se encontrava a palmeira real australiana, nos dois cultivos as plantas se encontravam com 36 meses de plantio a campo, estabeleceu-se 3 tratamentos: Pleno sol (PS), Meia sombra (MS) e Sombra (S), onde foram realizadas duas medições nos quais foram avaliados: caracteres agronômicos e fisiológicos, obtidos através do IRGA. Para esses caracteres uma análise preliminar dos dados foi desenvolvida para caracterizar a população amostrada. Calculou-se a média, o desvio padrão, o coeficiente de variação e os valores máximo e mínimo. Empregou-se o teste de Tukey adotando-se nível de 5 % de probabilidade. As análises foram complementadas com o estudo de correlações lineares, além das análises histológica e ultraestrutural, o delineamento empregado foi o inteiramente casualizado. Nos resultados observados em açaí, para o caráter diâmetro tanto o valor do diâmetro da mãe, como nos seus perfilhos (1, 2 e 3), o ambiente MS se mostrou mais adequado para a obtenção de um diâmetro maior. O número de perfilho (CV 32%) para o tratamento PS foi de 7,67, na MS 9,5 e na sombra 5,67, mostrando que existe uma maior tendência em se encontrar maior número de perfilhos em ambientes sombreados. Dentre os caracteres relacionados, os que apresentaram maior variabilidade foram o número de perfilho e número de folhas, com CV variando entre 32 a 29%. Adotando-se o teste de Tukey não houve diferença significativa nos parâmetros estudados, mostrando que existe uma tendência em estabilizar as medidas de caráter agronômico, independente de sua luminosidade. Para os caracteres fisiológicos ao longo do período experimental não houve diferença entre as respostas da fotossíntese, condutância estomática e transpiração. Para os resultados da palmeira real australiana obtidos, o caráter número de folhas (CV 7%), observa-se que o número de indivíduos avaliados (40 plantas/ tratamento) foram suficientes para constituir uma amostra representativa da população, parecendo haver pouca variabilidade para ser explorada, isto pode ser devido à base genética restrita da mesma. Os coeficientes de variação estudados variaram de 7 % (número de folhas) a 19% (diâmetro médio da planta). Para os caracteres fisiológicos houve diferença significativa entre os caracteres. Na análise histológica e ultraestrutural houve diferença mostrando que plantas cultivadas a pleno sol possuem maior tamanho de parênquima paliçádico e maior número de estômatos. / The present work involves two species of producing heart of palm: assai palm (Euterpe oleracea) and the king palm (Archontophoenix alexandrae) with objective: to measure the agronomic and physiological characters, in 3 environments of luminosity, to study the anatomy of the palm and to evaluate the behavior of the two species in sight to direct the producer, in better luminous surrounding which must be planted the species. The assumed hypothesis was: the growth and development in conditions of different radiation, cause physiological and anatomical modifications that affect the performance of the plants and its production. The experiments were carried out in two places: the assai palm was carried out in Piracicaba (22o42\'11\"S and 47o38\'09\"W, 531 altitude m), and king palm was in Pirassununga (21º59\'46\"S, 47º25\'33\" W, and 627 altitude m). The crops were with 36 months of plantation in the field, there were established 3 treatments: full sun (PS), half shade (MS) and shade (S), in the plants populations there were made agronomic and physiological evaluations. For these characters a preliminary analysis of the data was developed to characterize the population used. It was calculated average, standard desviation and the coefficient of variation and the values maximum and minimum. The Tukey test was used adopting 5 % of mistake probability. The analyses had been complemented with the study of linear correlations, beyond the analyses histological and ultrastructural, the completely randomized delineation was used to evaluate the results. In the results observed in assai palm, for the character diameter of the trunk and palm girth (1, 2 and 3), the environment MS showed more adequate for a bigger diameter. The number of palm girth (CV 32%) for treatment PS was of 7,67, in MS 9,5 and shade 5,67, showing that it exists a bigger trend to find more number of girth in environments with more shade. Among the related characters, the ones that had presented greater variability had been the number of palm girth and leaf number, with CV 32 29%. Adopting the Tukey test it did not have significant difference in the studied parameters, showing that a trend in stabilizing the measures of agronomic character exists, independent of its luminosity. For the physiological characters during the experimental period it did not have difference enters the answers of the photosynthesis, stomatal conductance and transpiration. For the results of the king palm gotten the character leaf number (CV 7%), it is observed that the number of evaluated individuals (40 plants treatment) had been enough to constitute a representative sample of the population, having seemed to have little variability to be explored, this can have the restricted genetic base of the same one. The studied coefficients of variation had varied of 7 % (leaf number) 19% (average diameter of the plant). For the physiological characters it had significant difference between the characters. In the histological and ultrastructural analysis it had difference showing that cultivated plants at full sun environment have bigger parenchyma and bigger number of stomata.