owth and ecophysiological variables in seedlings of Ziziphus thyrsiflora and Myroxylon balsamum nursery grown

The objective of the present study was to evaluate the growth strategy, stomatal control and water potential seedlings of ebony (Ziziphus thyrsiflora) and balsam (Myroxylon balsamum) in optimum humidity condictions of the substrate in the nursery. 18-month-old seedlings were transplanted into 5 L pots and grown for three months in nursery conditions. At the end of this period, the following were evaluated: stem height, diameter at the base of the stem, relative growth rate (TCR) in height and diameter, maximum rooting depth, soil water content (SWC), predaw water potential (Ψpd), stomatal conductance (Gs), and various indices of leaf water status (relative water content, CHR; water content for saturation, CAS; water deficit for saturation, DAS). The results indicated that Z. thyrsiflora showed greater height, diameter and TCR in diameter; not observing differences between species regarding the maximum rooting depth (50 cm). Although the two species were watered at the same time with the same dose, Z. thyrsiflora registered a lower SWC than M. balsamum when Ψpd was measured; which was reflected in a lower Ψpd (Z. thyrsiflora, Ψpd = -0.74MPa; M. balsamum, Ψpd = -0.52 MPa) and higher CAS (Z. thyrsiflora, CAS = 0.27 g H2O g-1 PS; M. balsamum, CAS = 0.14 g H2O g-1 PS). SWC correlated positively with Ψpd and negatively with CAS. Z. thyrsiflora maintained higher Gs values ​​(191.10 molH20.m-2.s-1); with respect to M. balsamum (100.84 molH20.m-2.s-1). Z. thyrsiflora showed an anisohydric strategy and M. balsamum an isohydric strategy.

• المؤلف الرئيسي: Mendoza Chumo, Dolores Rosalía (author)
• مؤلفون آخرون: Naranjo Moran, Gibelly Lisbeth (author), Miranda, Esteban Chirino (author)
• التنسيق: article
• اللغة: spa
• منشور في: 2021
• الوصول للمادة أونلاين: https://revistasespam.espam.edu.ec/index.php/Revista_ESPAMCIENCIA/article/view/268