Leaf growth parameters in coffee plants were determined by axis order. The duration of leaf expansion contributed to phyllochron determination. Leaf growth parameters varied according the position of the axis supporter along the vertical profile, suggesting an effect of axes age and micro-environmental light modulations.

Water availability, light, management practices, and harvest time impacts on Coffea arabica L. yield and bean quality remain uncertain. It was hypothesized that the soil water and light availability could impact berry distribution, yield, and bean chemical attributes within the plant canopy. Therefore, it was aimed to study berry yield, berry distribution, and bean chemical traits along the canopy strata of four coffee genotypes (Iapar 59, Catuaí 99 and two Ethiopian wild accessions, ‘E083′ and ‘E027′), cultivated with (IRR) and without irrigation (NI) in the two initial harvest years. The maximum height of berry occurrence was lower in NI than in IRR plants in both harvest years. In the 2nd harvest year, higher leaf-to-fruit ratio was found under NI than under IRR for all genotypes, except for Catuaí 99, while the most regular berry distribution among canopy strata was obtained in IRR ‘E083′, the highest bean yield in IRR ‘E083′ and Iapar 59, and the highest percent of useful bean biomass in NI Catuaí 99. The reduced lipid content under IRR was more important in the 1st (all genotypes) than in the 2nd harvest year (Iapar 59 and ‘E027′). As a novelty, chemical bean composition was additionally impacted by light availability along the canopy strata. Proteins declined from bottom (shaded) to upper (highly light exposed) strata, regardless of genotype and harvest year. Similar stratification was observed in caffeine in the 2nd year. Although some traits were somewhat changed among strata, no substantial quality changes occurred, thus allowing that harvest might include the entire plant and not only some specific strata. Iapar 59 and ‘E083′ showed chemical composition usually associated with high bean quality, with the highest lipid, sucrose, and soluble sugar contents, and the lowest caffeine, chlorogenic acids, and phenolic components among four genotypes, but Iapar 59 plants were less affected in their yield under NI. Based on additional responses from space occupation and yield only under IRR, the wild accession ‘E083′ must be considered in future breeding programs as promising material for intensive input conditions. High bean quality and the less variated yield under lower soil water availability qualified the Iapar 59 as the most prominent among the four genotypes.

Accurate model of structural elements is necessary to model the foliage and fruit distributions in cultivated plants, both of them being key parameters for yield prediction. However, the level of details in architectural data collection could vary, simplifying the data collection when plants get older and because of the high time cost required. In the present study, we aimed at reconstructing and analyzing plant structure, berry distributions and yield in Coffea arabica (Arabica coffee), by using both detailed or partial morphological information and probabilistic functions. Different datasets of coffee plant architectures were available with different levels of detail depending on the tree age. Three scales of decomposition—plant, axes and metamers were used reconstruct the plant architectures. CoffePlant3D, a software which integrates a series of mathematical, computational and statistical methods organized in three newly developed modules, AmostraCafe3D, VirtualCafe3D and Cafe3D, was developed to accurately reconstruct coffee plants in 3D, whatever the level of details available. The number of metamers of the 2nd order axes was shown to be linearly proportional to that of the orthotropic trunk, and the number of berries per metamer was modeled as a Gaussian function within a specific zone along the plagiotropic axes. This ratio of metamer emission rhythm between the orthotropic trunk and plagiotropic axes represents the pillar of botanical events in the C. arabica development and was central in our modeling approach, especially to reconstruct missing data. The methodology proposed for reconstructing coffee plants under the CoffePlant3D was satisfactorily validated across dataset available and could be performed for any other Arabica coffee variety.

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Drought stress is one of the most severe environmental constraints on plant production. Under environmental pressures, complex daily heliotropic adjustments of leaflet angles in soybean can help to reduce transpiration losses by diminishing light interception (paraheliotropism), increase diurnal carbon gain in sparse canopies and reduce carbon gain in dense canopies by solar tracking (diaheliotropism). The plant materials studied were cultivar BR 16 and its genetically engineered isoline P58, ectopically overexpressing AtDREB1A, which is involved in abiotic stress responses. We aimed to follow the movements of central and lateral leaflets in vegetative stages V7-V10 and reproductive stages R4-R5, integrating the reversible morphogenetic changes into an estimate of daily plant photosynthesis using three-dimensional modeling, and to analyze the production parameters of BR 16 and P58. The patterns of daily movements of central leaflets of BR 16 in V7-V10 and R4-R5 were similar, expressing fewer diaheliotropic movements under drought stress than under non-limiting water conditions. Daily heliotropic patterns of lateral leaflets in V7-V10 and R4-R5 showed more diaheliotropic movements in drought-stressed P58 plants than in those grown under non-limiting water conditions. Leaf area in R4-R5 was generally higher in P58 than in BR 16. Drought significantly affected gas exchange and vegetative and reproductive architectural features. DREB1A could be involved in various responses to drought stress. Compared with the parental BR 16, P58 copes with drought through better compensation between diaheliotropic and paraheliotropic movements, finer tuning of water-use efficiency, a lower transpiration rate, higher leaf area and higher pod abortion to accomplish the maximum possible grain production under continued drought conditions.

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