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A simple, practical, and low-technology approach was developed to fabricate corrugated bamboo particleboards (CBP), a novel bamboo product with a corrugated structure, from bamboo waste (planer waste). This product could be manufactured anywhere in the world where the bamboo industry develops. The selected mechanical and physical properties of CBP were prepared with urea formaldehyde resin at three press temperatures and two density levels and were evaluated. The results showed that the performance of CBPs is highly dependent upon the board density. The static bending strength of CBP laminated with MDF initially increases, and then decreases with increasing press temperature. Increasing the magnitude of the press temperature has a slightly positive effect on the thickness swelling and water absorption. Compared with the excellent mechanical strength of CBP (laminated with MDF), the thickness swelling value of this bamboo-based particleboard without any waterproofing treatment was lower than the minimal requirement of the EN standard.

Plant height, as one of the important agronomic traits of rice, is closely related to yield. In recent years, plant height-related genes have been characterized and identified, among which the DWARF3 (D3) gene is one of the target genes of miR528, and regulates rice plant height and tillering mainly by affecting strigolactone (SL) signal transduction. However, it remains unknown whether the miR528 and D3 interaction functions in controlling plant height, and the underlying regulatory mechanism in rice. In this study, we found that the plant height, internode length, and cell length of internodes of d3 mutants and miR528-overexpressing (OE-miR528) lines were greatly shorter than WT, D3-overexpressing (OE-D3), and miR528 target mimicry (OE-MIM528) transgenic plants. Knockout of D3 gene (d3 mutants) or miR528-overexpressing (OE-miR528) triggers a substantial reduction of gibberellin (GA) content, but a significant increase of abscisic acid (ABA) accumulation than in WT. The d3 and OE-miR528 transgenic plants were much more sensitive to GA, but less sensitive to ABA than WT. Moreover, the expression level of GA biosynthesis-related key genes, including OsCPS1, OsCPS2, OsKO2 and OsKAO was remarkably higher in OE-D3 plants, while the NECD2 expression, a key gene involved in ABA biosynthesis, was significantly higher in d3 mutants than in WT and OE-D3 plants. The results indicate that the miR528-D3 module negatively regulates plant height in rice by modulating the GA and ABA homeostasis, thereby further affecting the elongation of internodes, and resulting in lower plant height, which adds a new regulatory role to the D3-mediated plant height controlling in rice.

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