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On the way to the airport Dana managed to squeeze in one more garden visit while I was up in Vancouver, at the home of Gary Lewis. Gary owns Phoenix Perennials—which we also visited, that will be Friday’s post—and is the author of  The Complete Book of Ground Covers (which I own, and still need to write a review of). This is the view from the sidewalk…

It’s so much better than just a fence, isn’t it? A plant smorgasbord for those walking past.

Although the sections with a fence were pretty great as well. I thought maybe this style was unique to the property but saw a couple of similar nearby.

During the Modern Buyer RO-Fruit and Vegetables show on the 21st of November Tatayoyo once again secured an award, this time the Best Product Award. The journey of Tatayoyo in RomaniaThe story began in 2023 when a team from Romanian retailer Mega Image, along with the management of Holland Farming Agro…

Sendot recently launched a new data portal that hopes to take the way growers manage and analyze their data to the next level. Sendot’s Erwin Grafe and Arie Draaijer talk about the platform’s new capabilities and what this means for the agricultural sector. Portal as an optimization tool”Our new data portal…

With the arrival of the peak export season ahead of Christmas, shipping capacity has been increasingly constrained since November, driving up freight costs. During the South American mango season, Beijing Sino-agricultural Biosciences Co., Ltd., a supplier of temperature data loggers for the fruit and…

Researchers have identified two fungal enzymes that hijack the immune system of plants, playing a critical role in the colonization of plant roots. These findings open new avenues for interventions in both medicine and agriculture.

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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.

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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.

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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.

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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.

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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.

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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.

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Our results from transcriptomics extend the understanding of the gene expression and major events associated with embryogenesis progression in Taxodium distichum × Taxodium mucronatum.

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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.

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Pisonia grandis R. Br. is a tree commonly found in urban coastal and tropical regions, valued for its ornamental beauty and utility in agroforestry and traditional medicine. To facilitate its propagation, particularly through in vitro techniques, this study aimed to refine a propagation system by inducing adventitious buds from node explants of mature tree. The study revealed that the Murashige and Skoog (MS) medium, supplemented with 30 g L⁻¹ sucrose and 2.0 mg L⁻¹ thidiazuron (TDZ), effectively stimulated bud break. Furthermore, a combination of 1.0 mg L⁻¹ TDZ and 0.5 mg L⁻¹ α-naphthalene acetic acid (NAA) yielded optimal shoot multiplication, resulting in an average of 16.0 shoots per explant with a length of 5.9 cm. In contrast, utilizing 1.0 mg L⁻¹ 6-benzylaminopurine (BAP) and 0.5 mg L⁻¹ NAA led to producing 10.0 shoots with a height of 3.7 cm. Incorporating TDZ significantly enhanced shoot numbers, size, and overall health of the shootlets. Microscopic analysis revealed that leaves and petioles derived from the TDZ and NAA combination exhibited desirable features, such as a thick cuticle, well-differentiated epidermis, mesophyll, vascular tissues, stomata, and improved vein density compared to those derived from BAP and NAA. The maximum root percentage (87.5%) and adventitious root formation (averaging 8.0 roots with a length of 6.2 cm) were observed on half-strength media supplemented with 1.5 mg L⁻¹ indole-3-butyric acid (IBA). Conversely, NAA fortification resulted in lower rooting percentages (77.8% response with an average of 4.7 roots measuring 4.0 cm in length). Subsequently, the rooted plantlets were successfully acclimatized using a mixture of soilrite®, cocopeat, and garden soil (1:1:1 v/v ratio), with a survival rate of 92.0% in the field. This study contributes valuable insights into the optimized use of growth regulators for the large-scale propagation of P. grandis and related species, ensuring the production of micro-morpho-structurally stable plantlets.