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Drought stress affects physiological parameters but not tuber yield in three Andean potato (Solanum tuberosum L.) cultivarsshowed values greater than 0.8 for all DS cultivars under DS, suggesting the absence of non-stomatal limitations for A. The Chl content increased in the Es cultivar under DS from 5 to 7 DAT compared to WW plants. Carotenoids (Ca) contents, the Car/Chl ratio, and EL increased in the three DS cultivars. There were no differences in yield and growth parameters between WW and DS cultivars. These results suggest that the three cultivars developed mechanisms to overcome the stress. One of these mechanisms could be the early synthesis of Car, which may maintain photosystem II function under water stress.

<p><strong> Objective.</strong> To develop sexual propagation methodologies for <em>Montanoa quadrangularis </em>Schultz  Bipontianus (<em>arboloco</em>). <strong>Materials and methods. </strong>Seeds were harvested from trees grown at the Chilaca environmental station (Geoambiente Ltda.) located in Pacho, Cundinamarca, Colombia. The study was carried out in two phases: firstly, substrate effect on germination responses was evaluated in seedbed conditions. Substrates evaluated were: local soil, local soil mixed with worm humus, and peat. Additionally, two spatial arrangements were assessed:  seeds sown at random and at 0.5 cm in depth. Secondly, in nursery conditions the effect of the substrates local soil, local soil mixed with worm humus and peat, as well as the effect of developmental stages of the plants (with 2, 4, and 6 leaves) on their further growth and development were evaluated. <strong>Results. </strong>In seedbed conditions, the germination capacity was highly influenced by peat substrate (83.67%) whereas in local soil the germination capacity was 40.83%.   In  nursery conditions, 6-leaf plants grown  in  local soil mixed with worm humus showed the best responses on parameters such as  plant total length  (9.51 cm), leaf area (36.69 cm²), and total dry weight (0.10 g). <strong>Conclusions. </strong>The type of substrate used in seedbed conditions influenced the germination capacity of <em>M</em><em>. quadrangularis</em> seeds. The substrate and the developmental stage of the plant had a significant influence on the growth and development of <em>arboloco</em> plants.</p> <p><strong>Key words: </strong>germination indices, plant growth and development, forestry species.</p><br />