🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Xerophyte community composition and structure Picture a landscape where water is a precious commodity, a realm of scorching sun and gritty soil. This is the domain of xerophytes, […]
The impact of grazing on xerophyte communities Read More »
🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Seed Structure of Cycads Cycads, often dubbed “living fossils,” possess a unique seed structure that reflects their ancient lineage. Unlike the encased seeds of flowering plants, cycad seeds
Cycad seed morphology and germination Read More »
🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Understanding Dragon Tree Light Needs The majestic dragon tree (Dracaena marginata), with its spiky foliage and intriguing silhouette, is a popular choice for indoor gardening. But even these
Dragon tree light requirements Read More »
🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Identifying Aloe Plicatilis The aloe plicatilis, also known as the fan aloe or folding aloe, is a truly unique plant within the South African flora. Its most distinctive
The unique beauty of aloe plicatilis Read More »
🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Understanding Aloe Vera’s Composition The magic of aloe vera isn’t just skin deep; its potent composition holds a treasure trove of beneficial compounds that contribute to overall health,
Aloe vera and immune system support Read More »
🌿 Discover the Perfect Plants for Your Space! 🌿 Explore our handpicked collection of cycads, aloes, seeds, and more to transform your garden or landscape. Shop Now Cycad Biology and Ecology Cycads, often mistaken for palms or ferns, are ancient seed plants with a fascinating history stretching back to the Permian period, some 280 million
Cycads and their interactions with other organisms Read More »
Hydraulic properties of wetwood differ from normal sapwood: hydraulic conductivity is null and water contained in wetwood is totally trapped. Wetwood could result from a bad healing of dead branches.
Wetwood is a common phenomenon in silver fir (Abies alba Mill.), posing technical challenges for its industrial use. In this study, we thoroughly characterized the properties of this particular wood, investigating the mechanisms governing its formation and exploring its potential physiological relevance for trees. To address these objectives, we used a wide range of techniques, offering a comprehensive insight into the structure of wetwood at different scales, from cellular to whole-tree. Our results revealed significant variability in moisture distribution in the heartwood of the silver fir trees studied, suggesting the absence of a predefined distribution pattern. The physical properties of wetwood differ from those of sapwood, notably in terms of its hydraulic conductivity, which is null. In addition, our study demonstrated that the anatomical characteristics of wetwood are identical to those of normal dry heartwood, including features such as aspirated tori in bordered pits and the absence of nuclei. These results suggest a normal initial duraminization process followed by a progressive resaturation of the heartwood of silver fir. Taken together, these observations strongly suggest that the water present in wetwood is trapped and unavailable for use by the tree, particularly under conditions of prolonged drought.
Mechanism of wetwood formation in silver fir (Abies alba Mill.) Read More »
The deciduous species of the Aronia and Pourthiaea genera are differentiated by the finger-shaped colleters present on the midrib of the adaxial side and the pronounced cuticular folding.
This work presents data on taxonomically significant features of leaf micromorphology in six deciduous species from the closely related genera Aronia and Pourthiaea of the subtribe Malinae (formerly Pyrinae, Maloideae) in the family Rosaceae. All species were found to have hypostomate leaves with numerous anomocytic stomata on the abaxial side. However, Aronia arbutifolia, Pourthiaea arguta, and P. villosa showed single stomata on leaf teeth on the adaxial leaf side. All species exhibited stomatal dimorphism, with a large single ‘primary’ stomata at the center of a cluster of smaller ‘secondary’ (ordinary) stomata. Aronia species were characterized by well-defined cuticular striations on the surface of the adaxial epidermis, as well as cuticular radial folds and peristomatic folds in both types of stomata. Cuticular folding in Pourthiaea species is restricted to radial folds in primary stomata and is less pronounced or absent in secondary stomata. All species of Aronia and Pourthiaea have colleters of deltoid or elongated shape in leaf teeth. In A. mitschurinii and A. arbutifolia, rounded colleters were found in the sinuses between the leaf teeth. Aronia species have the unique feature of forming a special type of colleters on the adaxial side of the leaf midribs. In contrast, Pourthiaea species lacked similar structures. The secretion of the colleters showed an intense peak at 670-674 nm with a small shoulder in the range of 695-740 nm in its fluorescence spectrum. The micromorphological features of the studied leaf structures can serve as taxonomic characters in the genera Aronia and Pourthiaea.
Micromorphology of the leaf structures of Aronia Medik. and Pourthiaea Decne (Rosaceae) Read More »
Flexure wood formation is not systematically observed as a part of thigmomorphogenetic syndrome induced by wind. Its formation depends likely on the dose of mechanical signal perceived and the tree size-dependent strategy to resist wind loads.
Formation of a specific wood tissue called flexure wood often accompanies the thigmomorphogenetic syndrome in mechanically stimulated trees. Flexure wood exhibits high microfibril angle allowing for increase in the stem flexibility and higher resistance to post-elastic damage during repeated loadings. In this study, we examine the microstructure and the properties of wood produced by beech poles submitted to increased mechanical stimulus. Contrary to previous results obtained on poplar saplings, aside a little decrease in density no changes in the microstructure or the post-elastic properties of wood were observed in beech poles. While in saplings wood properties explained 25% of the resistive moment increase and 50% of the maximal curvature decrease, their relative contribution was of 6% for the resistive moment and 5% for the maximal curvature decrease in beech poles. These apparent discrepancies between our results and previous studies were explained by a possible combination of three factors: (i) experienced level of mechanical stimulus, (ii) tree size-dependent shift in the strategy to resist wind loads and (iii) the species sensitivity to thigmomorphogenetic syndrome. We further suggest the use of juvenile transition as an indicator of the species strategy to cope with environmental signals adopting a broader view of the adaptive capacity of a given species.
Our results from transcriptomics extend the understanding of the gene expression and major events associated with embryogenesis progression in Taxodium distichum × Taxodium mucronatum.
Zygotic embryogenesis is a critical process during seed development in which the plant body plan is established and the meristems responsible for all post-embryonic growth are determined. Taxodium ‘Zhongshanshan’ is a series of superior interspecies hybrids of T. distichum and T. mucronatum and has been widely planted in southeastern China. Understanding the molecular, cellular and metabolic processes of embryonic development will provide important information on the somatic embryogenesis of T. ‘Zhongshanshan’ and further developing zygotic embryogenesis research. In the present study, we sequenced the transcriptomes of zygotic T. distichum × T. mucronatum embryos at several developmental stages, covering most of embryogenesis. Total RNA samples from six zygotic embryo developmental stages were collected for high-throughput RNA sequencing. In total, 46,798 unigenes were identified, and 12,846 differentially expressed genes were annotated. Genes involved in carbohydrate metabolic, such as glycoside hydrolase-, alpha-xylosidase- and xyloglucan endotransglycosylase-encoding genes, were over-represented in early embryogenesis. Genes associated with auxin, gibberellin, and cytokinin signaling pathways and epigenetic genes related to chromatin remodeling, DNA methylation, and histone deacetylase showed significant differential expression during the embryo development process. Moreover, a number of transcription factors related to embryonic development were identified, among which WUSCHEL HOMEOBOX (WOX), NO APCAL MERISTEM (NAM), and LEAFY COTYLEDON1 (LEC1) being more relevant during early and mid-embryogenesis stages. Our results will provide a valuable resource for future studies and will be helpful to the research of T. ‘Zhongshanshan’ breeding programs.
