In this study, we describe the seed imbibition of 14 different species, from crop, forest, and native species potentially able to recover landscapes and form sustainable green cities. Seed imbibition is a fundamental physical and physiological process for reactivating metabolism and hydrolytic enzymes that will provide seed germination. We verified that the water imbibition is more closely governed by differences between osmotic potential (Ψ_w) and surrounding media than seed weight or seed hardness. In turn, seeds of Spondias tuberosa and Euterpe oleracea that have a Ψ_w of −75 MPa and a tegument as hard as 200 N imbibed an insignificant volume of water. Consequently, their metabolism is not significantly affected comparing the non-imbibed seeds and 120-h-imbibed seeds. Malpighia glabra or Annona squamosa also show very negative Ψ_w where the seed coat hardness is less evident; however, in these species, the seed imbibition increased the respiration rate by eight- to ten-fold in 120 h-imbibed-seeds than non-imbibed-seeds. The high-water absorption in M. glabra (49%) seems to be due to its highly convoluted tissue in the dry state, while in J. curcas and A. squamosa the presence of a highly porous seed coat must have favored seed imbibition and prompt metabolic reactivation.

Canola is the second-largest oil seed crop in the world, providing oil mainly composed of long-chain fatty acids (C14 to C20). When mixed with fossil-diesel, canola-based biofuel can be used in passenger vehicles, trucks, or even in aviation. Canola is the most productive type of biofuel due to its oil’s long-chain and unbranched fatty acid composition, which makes it more fluid. However, canola yields are constrained by drought and salinity that can aggravate climate change, resulting in negative consequences. Therefore, it is becoming necessary for studies that involved the canola salt-tolerant genotypes to consider soil salinization by use of saline soil or salinized soil by a non-efficient irrigation method. This study was carried out to assess the effects of salinity on seed germination and the effect of CaCl₂ (ψ_s = −1.2 MPa) on the promotion of regenerated plant memory when a new cycle of stress occurs. Our experiment shows that salt-stressed canola plants resulted in a high reduction in chlorophylls and carotenoids, with a high impact on gas exchange and a reduction in the efficiency of the chloroplast electron chain transporter, producing the negative effect of reduced molecules that affect the membrane integrity. However, canola seed priming could produce a memory in the regenerated plants when the second round of salt stress was applied. This research concludes that canola genotypes appear to have a tolerance mechanism against salt stress which could be an important trait for developing high-yielding canola varieties in future breeding programs under salt stress conditions.

Leaf area measurement is pivotal for plant physiologists. Hence, accurate measurement of their leaf area is incredibly relevant in agronomic terms. The plant Stevia rebaudiana is a sucrose-free plant species that is now vital to the global production of sucrose-free foods. Here, we estimated S. rebaudiana leaf area using a nondestructive methodology comprising allometric equations. Through leaf length (L), leaf width (W), and/or their product (LW) the leaf area was determined. One thousand leaves were sampled from four distinct S. rebaudiana genotypes for model construction. Linear or power models were generated, and the best equation was selected using a statistical criterion. The statistical criteria indicated that the linear models best suited all genotypes tested, included a function of LW, exhibited increased stability, and precisely estimated coefficients. ANOVA revealed that both generalized and combined equations were feasible. Nevertheless, grouping all genotypes into a single model was not possible as the genotype leaf architectures were very dissimilar.

The Stevia market is estimated to be USD 1.14 billion in 2028 due to its acceptance in the food and beverage industry. Stevia rebaudiana and its two more relevant edulcorants: stevioside (St) and rebaudioside A (Reb-A) can reach 450-fold sweeter than sucrose. The species is considered a long night plant, promoting flowering and shortening vegetative growth. Thus, to increase the leaf area and St and Reb-A increase, we broke the long night with a short light pulse, here called night interruption (NI). In this study, three NI times and two S. rebaudiana genotypes were tested to promote larger vegetative growth, flowering delay, and higher synthesis of steviol glycosides (SvGly). The main goal of this study was to demonstrate that NI increased net photosynthesis (9% to 20%), the internode length (59%), the leaf area (25%), while delays in 4 to 10 days of the flowering phase, impacting in 17% to 25% more St and Reb-A, respectively. Here we describe an inexpensive flowering delay, elongation of vegetative growth, allowing extended harvesting, which could yield four to five annual harvesting of leaves, increasing the production in 21% to 24% more St and Reb-A yield (kg ha⁻¹).

The Stevia rebaudiana Germplasm Bank at the University of Cordoba, Colombia, plays a pivotal role in conserving and efficiently utilizing the genetic variability of this species. Despite safeguarding promising genotypes with valuable traits, such as late flowering or a significant diterpenoid glycoside content, there is a need for an efficient mass propagation protocol for elite genotypes. This study aims to develop efficient in vitro micropropagation protocols for three elite S. rebaudiana genotypes (L020, L102, and Morita II). The methods employed various combinations of cytokinins and auxins following organogenesis protocols. The results showed that optimal shoot multiplication (17.3 shoots per explant) for L020 was achieved when cultures were grown on a basal medium MS supplemented with 1 μM 6-benzylaminopurine (BAP). For L102, optimal shoot multiplication (18.5 shoots per explant) was achieved in MS supplemented with 1 μM BAP and 0.5 μM naphthalene acetic acid (NAA), while for Morita II, the best treatment was an MS supplemented with 2 μM BAP and 0.5 μM NAA, producing 16.4 shoots per explant. This study successfully achieved micropropagation for promising S. rebaudiana genotypes, highlighting the significant impact of genotype on tissue culture, particularly in shoot multiplication. Developing a successful micropropagation system is crucial for the conservation and improvement of S. rebaudiana, with significant implications for its future use and performance.