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With the purpose of assessing the physiological responses of J. curcas young plants to drought and flooding, plants were subjected to three watering regimes: Control, drought and flooding. In the same period, five plants were submitted to drought (irrigation suspension), five to flooding and five were maintained near the field capacity (control). Measurements of leaf gas exchange, chlorophyll content, biomass of each organ (leaf, stem and root), biomass ratios, as well as the root:shoot ratio were made. When compared to control, drought and flooding treatments led to significant reductions (P≤.05) of gas exchange rates at 14 and 7 days after imposition treatments (DAIT), respectively. At the 16 th DAIT, significant reductions of leaf, root, stem and total biomass were observed, which resulted in changes of biomass partitioning of each organ. Significant reduction of leaf dry biomass (LDB) was observed in water deficit plants. Moreover, no significant effects of water deficit were observed in root dry biomass. Such response has led to a higher root:shoot ratio, suggesting an improved ability for water and nutrients uptake. In turn, flooding has induced a significant decrease in the dry biomass of all organs. Stem dry biomass ratio of flooded plants (0.67 g g -1 ) was significantly higher than that of control plants (0.41 g g -1 ), which, was seemingly due to leaf senescence and root system rotting of flooded plants. Altogether, present results reinforce the susceptibility of the studied genotype of J. curcas to flooding, as well as highlight some characteristics of drought tolerance in this species.

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RESUMO Óleos essenciais (EO) e extratos brutos aquosos (EBA) de Syzygium aromaticum e Cymbopogon nardus, e seus principais componentes químicos foram investigados para controle in vitro e in vivo de doenças causadas por Phytophthora nicotianae em tomateiro (Lycopersicon esculentum) e berinjela (Solanum melongena). Experimentos in vitro foram conduzidos pelo método de diluição em ágar com diferentes concentrações de óleos essenciais (OE’s) (0,1; 0,5; 1,0 ?L/mL) e extratos aquosos brutos (EBA’s) (1,0; 10,0 20,0%) para avaliar o potencial inibitório sobre o crescimento micelial e germinação de zoósporos. Com as porcentagens de inibição e concentrações inibitórias mínimas encontradas, realizou-se testes em frutos e plântulas sob ambiente controlado. As variáveis avaliadas foram o diâmetro médio das lesões formadas na superfície dos frutos e a incidência e morte de plântulas ao longo de seis e 15 dias de avaliação, respectivamente. Os produtos que mais inibiram o crescimento micelial e a germinação de zoósporos foram obtidos de S. aromaticum, nas concentrações de 0,5 ?L/mL e 10% de OE e EBA, respectivamente. Os tratamentos que mais retardaram a progressão da doença em frutos e plântulas, em comparação com o controle, foram o OE e EBA de C. nardus a 1,0 ?L/mL e 20%, respectivamente. Portanto, os produtos obtidos de S. aromaticum e C. nardus, têm potencial para reduzir o ataque deste patógeno em tomate e berinjela.

The cultivation of cocoa in full sun seeks technological modernization and yield increase; however, very little is known about this new production model. Thus, the aim of the present study was to: i) characterize six cocoa clones (PS 1319, CCN 51, CCN 10, SJ 02, CP 49 and PH 16), grown in full sun in Linhares, in the north of the state of Espírito Santo, regarding their physiology, leaf structure, yield and biometrics of fruits and seeds; ii) establishment of a nutritional sufficiency range through a leaf analysis and nutrient exportation of these six cocoa clones. The physiological evaluation and of the leaf structure took place by means of measurements of gas exchanges, chlorophyll flourescence, concentration of chloropastidic pigments, specific leaf area (SLA), stomatal density (SD) and potential quantum yield of photosystem II - Fv/Fm ratio. Yield was estimated by counting and weighing healthy seeds and fruits. For the biometrics of fruits and seeds, the following were evaluated: weight (LW); fruit length (FL) and diameter (FD), fresh weight of the shell (FWS), wet weight of the seed (WWA), number of seeds (NS) and individual weight of dry seed (IWDS). For the leaf sampling, four plants of each clone were randomly chosen, from which four diagnostic leaves were collected per plant. As for the fruit sampling, 10 ripe and healthy fruits were collected per clone and the separation of the shell and almonds was carried out. After the preparation of the leaf and fruit samples, they were sent to the laboratory for the quantification of the contents of mineral nutrients. The evaluation of almond yield was performed during the main and intercrop seasons and, for each clone, the healthy fruits and their seeds were collected, counted and weighed. After checking the high yield of the clones and the data normal distribution, the adequate sufficiency ranges were established considering μ ± σ. The trial was analyzed as a hierarchy classification, and for each one of the six clones, 14 plots were randomly plotted, each one composed of 1 plant (experimental unit). The clones presented differences in the evaluations of gas exchanges and the A values found were higher than the mean values in the literature, which suggests acclimatization of the clones grown in full sun to light intensity. Moreover, under high light intensity, the values of the Fv/Fm ratio indicated the absence of photoinhibition. There were significant differences for all the parameters of biometrics, except for LW, demonstrating expressive variability for the production of fruits and seeds. The clones presented a high yield of dried almond (1200 to 2900 kg ha -1 ) and the differences among clones in the contents of nutrients for the different compartments were expected, due to the variation of productivity among the materials. Adequate sufficiency ranges for each clone represent a first approach in conditions of cultivation in full sun in Brazil. The nutrient exportation by the shell was high, presenting potential for use as an organic fertilizer when returned to the culture. As for the exportation of some nutrients by the fruit, it reinforced the importance of nutritional replacement via fertilization, so that the reduction of the soil natural fertility does not occur. Finally, intensive cultivation of cocoa in full sun showed high production potential. Keywords: Theobroma cacao L. Ecophysiology. Plant nutrition. Leaf diagnosis.

The cultivation of cocoa is of great socio-economic importance worldwide. Cocoa beans are the essential raw material for chocolate production. The variability of cacao studied presents only a small fraction of the existing genetic diversity, mainly in the Amazon region. Furthermore, just a small part of this variability has been exploited in cocoa breeding. Thus, the present study processed the genetic evaluation and selection of cocoa clones, based on morpho-agronomical traits. For this, we evaluated 145 clones, during 37 harvests from, four consecutive years. The following traits were evaluated: total number of fruits collected (TNFC), total number of healthy fruits (TNHF), weight of wet seeds from healthy fruits (WWSHF), average weight of wet seeds per healthy fruit (AWWSHF), weight of dry seeds from healthy fruit (WDSHF), average weight of dry seeds per healthy fruit (AWDSHF), percentage of fruits with witches’ broom disease (PFWB), percentage of fruits with borer (PFBR), percentage of fruits with germinated seeds (PFGS), number of branches with witches’ broom disease (NBWB), and number of inflorescence with witches’ broom disease (NIWB). Significant differences (P < 0.05) among the clones were observed for all traits, which reveal an expressive variability and possibility of gains with selection. The highest significant correlations (P < 0.05) occurred between traits TNFC and TNHF (0.94), TNHF and AWWSHF (0.86), and TNHF and AWDSHF (0.86). Based on the selection index, the clones POUND 12 and CAB 12, 228, 253, 257, 258, and 422 were the most suitable for selection.