Ciências Biológicas e da Saúde
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Item Toxicity assessment of pesticides and biopesticides on wild and managed bees (Hymenoptera, Apoidea), and richness evaluation in mediterranean and tropical agroecosystems(Universidade Federal de Viçosa, 2025-02-21) Catania, Roberto; Siqueira, Maria Augusta Lima; http://lattes.cnpq.br/8921922664198131Bees (Hymenoptera, Apoidea) are the main pollinator insects for wild and cultivated plants, being of crucial environmental and economic importance. Their global decline, driven by anthropogenic factors, including the use of synthetic pesticides, is an alarming concern. Biopesticides can be a viable alternative for the protection of cultivated plants due to their high selectivity and short environmental persistence. Despite their natural origin, biopesticides can cause lethal and sublethal effects on non-target organisms. During this PhD project, we studied the toxicity of synthetic pesticides and biopesticides on wild and managed bees, using different products marketed in Mediterranean and tropical areas, and some nanoformulations of essential oils (EOs) tested on pests but not yet commercialized. Lethal and sublethal effects caused by pesticides commonly used in Italian and Brazilian agroecosystems, including greenhouses, were evaluated, with particular attention to some biopesticides of botanical origin, such as EOs. Synthetic and botanical pesticides caused lethal and sublethal effects on social (honeybees, bumblebees, Neotropical stingless bees), and solitary bees. Specifically, EOs caused lethal effects after topical and oral exposure to Apis mellifera, Bombus terrestris, Osmia bicornis, and Melipona mondury. Changes in feeding behavior and locomotor alterations caused by exposure to EOs were observed on the stingless bee M. mondury. Commonly used pesticides and biopesticides caused reduced survival of ground-nesting wild bees of Andrena and Eucera species, and altered the locomotor behavior of managed bees. Synthetic insecticides used to protect greenhouse tomato plants reduced the survival and caused changes in feeding behavior, and midgut alterations in B. terrestris. These results may be important for the appropriate use of pesticides and biopesticides in integrated pest and pollinator management, providing crucial data for the conservation of pollinating insects. In addition, populations of wild bees were studied in two tree crops in Southern Italy, one Mediterranean (almond) and one tropical (mango), comparing species richness and abundance between integrated and organic management. Keywords: ecotoxicology; social bees; solitary bees; lethal effects; sublethal effects; essential oils; management; almond; mango exposure; integrated pest and pollinator.Item Developing novel natural and synthetic tools for a more sustainable management of Euschistus heros (Hemiptera: Pentatomidae)(Universidade Federal de Viçosa, 2025-02-20) Francesco, Leonardo Semençato; Oliveira, Eugênio Eduardo de; http://lattes.cnpq.br/4889276299285924Chemical control is the primary strategy for managing Euschistus heros in soybean production. However, excessive use of synthetic insecticides raises concerns about resistance development and impacts on non-target organisms, such as natural enemies and pollinators. This study evaluated essential oils and biorational molecules as sustainable alternatives. The essential oils of Minthostachys verticillata (peperina) and Pelargonium graveolens (rose geranium) were tested alongside the synthetic butenolide K16 for their toxicity against third instar nymphs of E. heros and selectivity toward Telenomus podisi and Apis mellifera. In order to determine their insecticidal potential, lethal concentrations (LC) were estimated for each treatment. For P. graveolens essential oil, the LC50 was 1,784 µL/L (?2= 4.1627, P = 0.2444), and the LC80 reached 5,368 µL/L. For M. verticillata essential oil, the LC50 was 2,483 µL/L (?2= 1.9762, P = 0.3723), and the LC80 was 5,365 µL/L. In addition, to parasitoid T. podisi, P. graveolens EO caused 0.83% mortality at LC10, 32.36% at LC50, and 83.86% at LC80. M. verticillata EO, resulted in 0.83%, 21.4%, and 75.18% mortality at the same concentrations, respectively selectivity only up to LC50. For the pollinator A. mellifera, LC80 mortality in the first five hours was 60.24% for P. graveolens and 31.39% for M. verticillata, with no mortality in the control group. The synthetic butenolide K16 showed strong insecticidal activity in a dose-dependent manner. The LC20 was 181.47 µg/L, LC50 was 423.48 µg/L, and LC20 reached 988.23 µg/L. K16 demonstrated selective toxicity, with Telenomus podisi showing no significant mortality at LC20 (P = 0.0014) but reaching 100% mortality at LC80 (P = 1), indicating loss of selectivity at higher concentrations. In Apis mellifera, mortality increased from 6.67% at LC20 to 28.33% at LC80, highlighting potential risks to pollinators. These results suggest that essential oils and butenolide-based molecules are potential alternatives to conventional insecticides. However, optimizing their application is crucial to minimize risks to beneficial organisms. Future research should focus on improving formulations, reducing environmental persistence, and evaluating field-scale efficacy to enhance sustainable pest management. Keywords: sustainable pest control; non-target organisms; selective toxicity; soybean insect management.Item Drivers of ecosystem functioning in secondary tropical forests: the roles of carbon stocks, endemic species, and anthropogenic disturbance(Universidade Federal de Viçosa, 2025-12-05) Silva, Nathália; Meira Neto, João Augusto Alves; http://lattes.cnpq.br/1814298753509846Understanding the mechanisms that structure biodiversity and determine carbon stocks in tropical forests is central in the face of global change, fragmentation, and intensified anthropogenic disturbances. In this thesis, we investigate the functional, phylogenetic, environmental, and anthropogenic determinants of carbon stocks and the functional diversity of endemic and threatened species in secondary forest fragments of the Atlantic Forest, one of the most endangered biomes on the planet. We used data from 23 fragments, where tree communities were sampled with information on functional traits, phylogenetic structure, and biomass, integrated with environmental variables and disturbance history. In Chapter 1, we evaluate how the mechanisms of niche complementarity and mass ratio regulate aboveground carbon stocks (AGC) and how abiotic factors and anthropogenic disturbances modulate these processes. We hypothesize that (1) the mass ratio mechanism will exert a greater influence on AGC; (2) aboveground carbon stocks will be positively related to environmental factors widely associated with increased productivity and biomass accumulation in tropical forests, such as higher temperature, water availability, and soil fertility; and (3) the influence of ecological mechanisms on carbon stocks will depend on levels of anthropogenic disturbance. In areas with low disturbance, we expect that niche complementarity will play a predominant role, since reduced anthropogenic pressure and greater ecological niche availability can support the coexistence of diverse functional strategies that promote biomass accumulation. Conversely, in highly disturbed areas, the mass ratio mechanism may exert a stronger influence on carbon stocks, as disturbance can select for more resilient or tolerant functional strategies. In Chapter 2, we expand the analysis to explore multiple carbon compartments (AGC, root biomass carbon – RC, and soil organic carbon – SOC), aiming to understand how functional diversity, trait dominance, phylogenetic diversity, and environmental and anthropogenic gradients interact to shape these stocks. We hypothesize that aboveground carbon stocks will be primarily influenced by water availability, soil fertility and functional structure of plants, with communities dominated by species with conservative traits storing more biomass and carbon aboveground. In addition, we expect phylogenetic diversity to have a positive effect on AGC through complementarity and niche partitioning. For root carbon, in addition to sharing similarities with environmental conditions favorable for AGC, since it also represents live biomass, we expect stronger associations with acquisitive functional strategies of plants, since fine roots need to cope with resource fluctuations in the soil. For soil organic carbon, we predict stronger associations with climatic seasonality and edaphic factors, since litter decomposition is constrained during dry periods and organic matter stabilization is favored, and it also appears to be reinforced by resource-conserving strategies that promote stabilization and generate more recalcitrant litter inputs. Finally, in Chapter 3, we explore the role of endemic and threatened species in the functional diversity of secondary tropical forests, evaluating their distribution in functional space and the potential consequences of their loss. We hypothesize that these groups occupy restricted subsets of functional space with more conservative strategies, and that their exclusion would reduce functional richness and dispersion, increasing the regularity of trait distribution. Together, the three chapters provide evidence that maintaining diversity and functional structure is fundamental to sustaining carbon stocks and ecosystem functions in Atlantic Forest remnants, highlighting the importance of conservation strategies that integrate biodiversity, key groups, the influence of anthropogenic degradation, and multiple carbon compartments. Keywords: ecosystem functioning; biodiversity conservation; trait-based ecologyItem Epibiotic relationships in marine hydrozoans (Cnidaria, Hydrozoa): influence of environmental factors and substrate type on the biology and diversity of hydroids(Universidade Federal de Viçosa, 2025-10-28) Araújo, Alessandra Lopes de; Cunha, Amanda Ferreira e; http://lattes.cnpq.br/4923391744037798Epibiosis is a very common spatial relationship among marine benthic invertebrates, in which one organism, the epibiont, lives on the surface of another living organism, the basibiont. Epibiosis can be epiphytic, when the epibiont associates with a plant substrate, or epizoic, when it occurs on an animal substrate. This relationship is not necessarily positive or negative and may even be neutral, depending on the context. Epibiotic relationships are frequently observed in marine hydroids (Hydrozoa, Cnidaria), which correspond to the sessile polyp stage of hydrozoans. Hydroids are capable of colonizing a wide variety of plant and animal substrates. Thus, this study aims to evaluate whether the frequency of generalist and specialist epibiotic interactions of marine hydroids is influenced by environmental factors (e.g., latitude and depth), and whether substrate type is related to life-cycle type (e.g., presence of fixed gonophores, medusa, or medusoid stages) and colony morphology, specifically branching patterns (erect branched, erect unbranched, stolonal, or solitary polyps). Regarding patterns of generalism and specialism along environmental gradients (latitude and depth), networks from the Arctic, Northern Temperate, and Tropical regions, as well as sublittoral zone 1 (2–100 m), showed significant modularity, suggesting a more specialist tendency than other regions. With respect to substrate type, life cycle, and colony morphology, hydroids with fixed gonophores showed greater associations with algae and other hydroids, whereas hydroids with a medusa stage were more frequent on hard corals and other hydroids. Erect branched colonies were more frequent on algae and other hydroids, while stolonal colonies were more commonly observed on hard corals and other hydroids. These results mainly indicate that generalism or specialism in hydroids and their respective substrates can vary according to environmental context and that substrates, although not determining factors of the life cycle, may be associated with reproductive strategies and colony morphology. Investigating the attributes involved in the diversity of marine hydroids is of great importance, particularly for understanding the processes that drive the evolution of hydrozoans. Keywords: epibiosis; Hydrozoa; hydroids; substrates; life cycle; morphology; network approach; generalism; specialismItem Sojas transgênicas com duas e três toxinas Bt: resistência prévia e efeitos transgeracionais como condicionantes do manejo de Spodoptera frugiperda(Universidade Federal de Viçosa, 2025-06-13) Moraes, João Gabriel Tardin de; Pereira, Eliseu José Guedes; http://lattes.cnpq.br/2250860245839004Sistemas intensivos de cultivo de soja, milho e algodão na América do Sul têm alterado o status de praga de Spodoptera spp. (Lepidoptera: Noctuidae) em soja sob adoção em larga escala de certas cultivares transgênicas produzindo toxinas de Bacillus thuringiensis (Bt). Nesse cenário, S. frugiperda destaca-se pela sua tolerância e resistência a Bt e é preciso compreender o impacto da composição de toxinas Bt produzidas nos tecidos da planta, dos estágios de desenvolvimento do inseto e da planta e dos potenciais efeitos (trans)geracionais resultantes da interação desses fatores. Assim, este trabalho objetivou determinar: i) o impacto de sojas Bt com 0, 1, 2, ou 3 toxinas Bt sobre a comunidade de artrópodes do cultivo; ii) o efeito letal das sojas durante os estágios de crescimento das plantas contra S. frugiperda de diversos genótipos e ínstares larvais; e iii) os efeitos subletais, geracionais e transgeracionais decorrentes da exposição dos insetos às toxinas Bt das sojas. Os resultados de dois anos de cultivo indicaram que as sojas Bt afetaram seletivamente os lepidópteros, mas não se detectou efeito delas na densidade populacional de inimigos naturais de pragas ou em artrópodes detritívoros. Nos tecidos foliares das plantas, a cultivar com Cry1Ac + Cry1A.105 + Cry2Ab2 foi a mais eficaz contra as lagartas neonatas, incluindo aquelas de populações resistentes a Bt Cry1 e Cry2, reduzindo o tempo médio de sobrevivência em até 74% e causando mortalidade >80% em 7 dias. As cultivares com Cry1Ac ou com Cry1Ac + Cry1F mostraram eficácia relativamente menor contra as lagartas. Observou-se queda significativa no índice de desempenho biótico na geração F1 das populações suscetível e resistente a Cry1 expostas às cultivares Bt na geração parental, indicando a presença de efeitos transgeracionais. A taxa intrínseca de crescimento populacional, estimada dos dados de desenvolvimento e fertilidade, apresentou valores negativos para essas populações, evidenciando efeitos subletais duradouros e transgeracionais. Esses resultados indicam que as sojas transgênicas Bt podem causar efeitos subletais que passam à geração seguinte e a soja com 3 toxinas Bt tem potencial para bom controle de S. frugiperda nos cultivos. Contudo, eles devem ser acompanhados e a adoção de programas de manejo integrado de pragas pode ser necessário para preservar a eficácia de controle de toxinas de Bt ativas contra as lagartas e o potencial produtivo nas culturas de soja, milho e algodão. Palavras-chave: lagarta-do-cartucho; Bacillus thuringiensis; toxinas Cry1 e Cry2; artropodofauna; efeitos letais; subletais.Item Green guardians of regenerative coffee: lacewing larvae as entomovectors, entomopathogenic fungi, and essential oil team up against coffee berry borer(Universidade Federal de Viçosa, 2025-04-28) Ferreira, Douglas da Silva; Venzon, Madelaine; http://lattes.cnpq.br/6558522786522599Regenerative coffee farming has gained prominence by promoting sustainable agricultural practices that restore ecosystems and improve farmers’ livelihoods. The use of sustainable alternatives to replace chemical pesticides has become a constant pursuit in agriculture, aiming to reduce environmental and health impacts. Coffee cultivation has increasingly adopted these sustainable practices; however, it still faces major challenges in controlling one of its main pests, the coffee berry borer (Hypothenemus hampei Ferrari, 1867). Products based on entomopathogenic fungi, such as Beauveria bassiana (Bals.-Criv.) Vuill., 1912, are used for this purpose. Nevertheless, their variable efficacy, potential impacts on non-target beneficial insects, and combined use with other biological control agents raise concerns about possible incompatibilities. This thesis therefore explored the interactions between B. bassiana and other promising biological control agents. In the first chapter, we demonstrated the non-pathogenicity of a commercial B. bassiana-based product (Granada®) against two species of green lacewings that are predators of the coffee berry borer: Chrysoperla externa Hagen, 1861 and Ceraeochrysa cubana Hagen, 1861. Results showed mortality rates below 5% for the natural enemies, compared to 95% for the coffee berry borer. Despite the low mortality in lacewing larvae, we aimed to investigate potential sublethal effects on them. With that in mind, the second chapter assessed potential sublethal effects on predation, foraging, reproduction, and life cycle of these two lacewing species. Results showed, surprisingly, low potential for sublethal effects, with only two notable findings: a change in the average foraging angle of C. cubana larvae, and reduced survival in adult males of C. externa. However, based on the experiments conducted, we did not find sufficient evidence to confirm sublethal effects in these two lacewing species. Building on these results, we progressed to investigate the possible role of lacewing larvae as spore carriers of B. bassiana, aiming to reach the coffee borer’s hidden refuges. This was the focus of the third chapter, where we obtained promising results using first-instar larvae of both lacewing species as potential entomovectors for controlling the coffee berry borer under laboratory and greenhouse conditions. However, further field investigation and formulation improvements are necessary to enhance spore adhesion to the larval body. Still aiming to evaluate the compatibility of biocontrol inputs, the fourth chapter investigated the antifungal and hormetic potential of essential oil from Varronia curassavica (erva-baleeira) on B. bassiana. Results showed an inductive effect at low concentrations (0.2%) and an inhibitory effect at higher concentrations (above 0.8%). This confirmed a hormetic effect at lower doses—meaning that exposure to small amounts of a toxic substance or stressor can stimulate beneficial responses in organisms—and an antifungal effect at higher doses. Thus, further studies should consider incorporating the essential oil into B. bassiana formulations to enhance fungal activity, as well as exploring its antifungal potential for plant disease management. In conclusion, this thesis addressed important knowledge gaps in the integrated pest management of coffee crops, aligned with the principles of regenerative coffee farming. Keywords: chrysopidae; biological control; insect vectors; Beauveria bassiana; erva-baleeira.Item Decision-making control systems of Anthonomus grandis grandis (Coleoptera: Curculionidae) in cotton fields using machine learning and digital tools(Universidade Federal de Viçosa, 2025-07-31) Oliveira, Andréa Aparecida Santos; Picanço, Marcelo Coutinho; http://lattes.cnpq.br/3763421583509972The boll weevil (Anthonomus grandis grandis Boh.) is one of the main pests of cotton (Gossypium hirsutum L.), infesting the reproductive structures of the plant and causing significant losses, which can compromise up to 100% of production. Digital and machine learning systems are modern tools capable of performing tasks that would normally be performed by human intelligence and exhibiting high precision while doing that together with the incorporation of all the required variables for a decision-making system. Despite the importance of cotton crops and A. grandis grandis, currently there are no records of studies that had been carried out on the use of digital tools and machine learning for decision-making in the control of the boll weevil. Thus, this work aimed to determine a model for predicting the seasonal variation of A. grandis grandis populations in cotton crops using Artificial Neural Networks (ANNs) and to develop a digital system for determining control levels for A. grandis grandis according to insecticide application technology, cotton lint price and crop yield. Although there are several ways to control the boll weevil, the most efficient is through the use of synthetic pesticides. The tools determined in this work are promising for optimizing the use of these pesticides, determining the appropriate time for pest control. Keywords: ANNs; digital systems; boll weevil; Gossypium hyrsutum.Item Efeitos do sombreamento, da competição e do fogo sobre o desenvolvimento inicial e morfofisiologia em três espécies do gênero Dimorphandra: implicações para a conservação e o manejo(Universidade Federal de Viçosa, 2025-11-28) Teixeira, Marcony Vinícius Januário; Souza, João Paulo de; http://lattes.cnpq.br/3025667694238203A variação na disponibilidade de luz, a competição interespecífica com gramíneas exóticas e o regime de fogo constituem fatores ecológicos que modulam a dinâmica da vegetação. A luz regula processos ecofisiológicos, interferindo na fotossíntese e balanço energético, na morfologia e alocação de biomassa. As gramíneas exóticas interferem na competição por água, luz e nutrientes, alteram a ciclagem de nutrientes e facilitam o fogo. O regime de fogo é um dos principais filtros ecológicos de savanas, cerrados e florestas sujeitas a distúrbios antropogênicos, regulando o recrutamento de espécies nativas. O objetivo foi avaliar se espécies congenéricas de Dimorphandra Schott apresentam respostas diferenciadas em seu desenvolvimento inicial em função da luz, competição e fogo durante o cultivo em casa de vegetação e no campo. Aos 285 dias após o plantio foram avaliados o crescimento inicial, biomassa, fluorescência da clorofila a e o teor de clorofila em resposta a variação na luminosidade e aos 473 dias após o plantio, os efeitos da luminosidade e competição com Melinis minutiflora P. Beauv. Aos 631 dias foram analisados os efeitos combinados da luminosidade e fogo. Os resultados mostraram que Dimorphandra exaltata Schott apresentou maior área foliar específica e crescimento aéreo, porém apresentou menor eficiência fotoquímica, sendo sensível aos efeitos da competição e fogo, com redução acentuada na biomassa e no desempenho funcional. A espécie Dimorphandra mollis Benth. manteve baixa alocação de biomassa para a parte aérea, investindo mais em raízes que parte aérea, com alta eficiência fotoquímica sob sombreamento e competição. Já Dimorphandra wilsonii Rizzini apresentou diferentes respostas em diferentes condições ambientais, destacando-se com maior produção de massa seca e eficiência fotoquímica, com maior resiliência ao fogo. Os resultados revelam estratégias funcionais contrastantes entre as espécies, indicando que o manejo deve levar em conta as características de cada espécie a ser utilizada. Palavras-chave: Cerrado; estratégias adaptativas; Mata Atlântica; pares congenéricosItem Recodificação de caracteres, análise filogenética e posicionamento de Cheloides e Pelomedusoides (Testudines, Pleurodira)(Universidade Federal de Viçosa, 2025-08-22) Lopes, Natália Benevenuto; Romano, Pedro Seyferth Ribeiro; http://lattes.cnpq.br/6159426661632560Os fósseis de tartarugas do Cretáceo sul-americano são fundamentais para entender a evolução de Pelomedusoides (Pan-Pleurodira), grupo que se diversificou do Cretáceo Inferior até hoje. Objetivou-se propor uma nova hipótese filogenética para Pelomedusoides e revisar o posicionamento deste grupo e de espécies relacionadas dentro de Pan-Pleurodira. A revisão de matrizes de caracteres morfológicos compreendeu a reinterpretação, combinação, redefinição e recodificação de caracteres seguindo a padronização semântica proposta por Sereno (2007). Foram realizadas análises de parcimônia com diferentes tratamentos de caracteres (aditivos, não aditivos e implied weighting), resultando em topologias variáveis. Platychelyidae foi recuperado como o primeiro grupo divergente de Pan-Pleurodira, seguido por Dortokidae. Chelidae dividiu-se em dois grupos morfológicos, ambos com representantes sul-americanos e australianos, sustentando uma origem pré- Gondwânica. Pelomedusidae foi recuperado como grupo-irmão de todos os outros Pelomedusoides, e assim, como Podocnemididae, mantiveram posições estáveis, com sinapomorfias robustas. Podocnemidinura foi recuperado, mas com Peiropemydidae incluído, enquanto Bothremydidae manteve o monofileticismo de suas tribos, exceto Kurmademydini. Euraxemydidae e Araripemydidae mostraram posições instáveis, alternando como grupos-irmãos de clados distintos dependendo da análise. Os resultados reforçam a complexidade filogenética de Pelomedusoides, destacando a necessidade de revisão de caracteres e inclusão de novos táxons. A dispersão transcontinental de Chelidae e a diversificação inicial de Pelomedusoides no Cretáceo sul-americano são sustentadas por evidências morfológicas e biogeográficas. Palavras-chave: Pelomedusoides; Cretáceo Inferior; paleontologia; sistemática filogenética; matrizes de caracteres morfológicosItem Respostas fotossintéticas, metabólicas e produtivas de cannabis medicinal (Cannabis sativa L.) sob déficit hídrico(Universidade Federal de Viçosa, 2025-08-06) Pena, Mateus Miranda; DaMatta, Fábio Murilo; http://lattes.cnpq.br/1650221824542729A seca é uma das principais limitações para a produtividade e o rendimento de canabinoides em Cannabis sativa, mas os mecanismos fisiológicos que explicam a variação genotípica nas respostas à seca ainda são pouco compreendidos. Hipotetizou-se que (i) genótipos mais vigorosos manteriam taxas fotossintéticas mais elevadas; (ii) a seca restringiria a fotossíntese tanto por limitações difusionais quanto não difusionais; e (iii) o déficit hídrico alteraria a produção de canabinoides de forma dependente do genótipo. Para testar essas hipóteses, dois genótipos contrastantes — um dominante em tetrahidrocanabinol (THC) e outro dominante em canabidiol (CBD) — foram cultivados em vasos sob condições de casa de vegetação, com a imposição de déficit hídrico no início da floração. As relações hídricas foliares permaneceram estáveis entre genótipos e tratamentos, indicando que os parâmetros hidráulicos não explicaram as diferenças de desempenho dos genótipos. Embora as plantas CBD tenham se mostrado mais vigorosas, elas não apresentaram maiores taxas fotossintéticas sob boa disponibilidade de água. Sob seca, as plantas THC dependeram principalmente da regulação estomática, enquanto as plantas CBD exibiram limitações adicionais no mesofilo e no metabolismo bioquímico, resultando em reduções mais acentuadas na taxa de fotossíntese. Apesar dos ajustes fotoprotetores contrastantes, ambos os genótipos apresentaram níveis semelhantes de dano oxidativo, sugerindo que a fotoproteção não foi um fator decisivo para sua divergência fisiológica. Em nível agronômico, as plantas THC mantiveram maior índice de colheita sob seca, maiores concentrações basais de canabinoides e biomassa de inflorescências com maior valor energético. Já nas plantas CBD, as reduções no conteúdo de canabinoides e no índice de colheita induzidas pela seca refletiram, em grande parte, uma maior limitação fotossintética e menor eficiência no uso de carbono. De modo geral, a resiliência de C. sativa à seca imposta no início da floração parece depender menos da estabilidade hidráulica e mais da manutenção do desempenho fotossintético, do metabolismo secundário e da partição eficiente de biomassa. Essas características representam alvos importantes para o melhoramento de genótipos mais adaptados ao cultivo sob disponibilidade hídrica cada vez mais variável. Palavras-chave: alocação de carbono; déficit hídrico; índice de colheita; performance fotossintética; rendimento de canabinoides.