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The article focuses on introducing a new Gardenia jasminoides cultivar named 'Yinzhan', detailing its origin, characteristics, and cultivation techniques. Topics discussed include the unique cup-shaped corollas of its flowers, the medicinal and ornamental value of the plant, and specific cultivation requirements for optimal growth.

The complexity of plant antioxidative systems gives rise to many unresolved questions. One relates to the functional importance of dehydroascorbate reductases (DHARs) in interactions between ascorbate and glutathione. To investigate this issue, we produced a complete set of loss-of-function mutants for the three annotated Arabidopsis (Arabidopsis thaliana) DHARs. The combined loss of DHAR1 and DHAR3 expression decreased extractable activity to very low levels but had little effect on phenotype or ascorbate and glutathione pools in standard conditions. An analysis of the subcellular localization of the DHARs in Arabidopsis lines stably transformed with GFP fusion proteins revealed that DHAR1 and DHAR2 are cytosolic while DHAR3 is chloroplastic, with no evidence for peroxisomal or mitochondrial localizations. When the mutations were introduced into an oxidative stress genetic background (cat2), the dhar1 dhar2 combination decreased glutathione oxidation and inhibited cat2-triggered induction of the salicylic acid pathway. These effects were reversed in cat2 dhar1 dhar2 dhar3 complemented with any of the three DHARs. The data suggest that (1) DHAR can be decreased to negligible levels without marked effects on ascorbate pools, (2) the cytosolic isoforms are particularly important in coupling intracellular hydrogen peroxide metabolism to glutathione oxidation, and (3) DHAR-dependent glutathione oxidation influences redox-driven salicylic acid accumulation. [ABSTRACT FROM AUTHOR]

Structure and crystalline behavior of the ternary system ZnO-BO-PO glasses were investigated by means of X-ray diffraction (XRD) and infrared Raman spectra. The research showed that number of the planar [BO] units increases with the increase of BO content. When the BO content is above ≥10 mol %, the relative content of planar [BO] units increases rapidly and causes weakening of the glass structure and decrease in the chemical stability. In the crystallized glasses the predominant crystal phase ZnPO decreases with the increase of BO content, while the crystal phase BPO increases with it, which cause the declining of chemical stability and the decrease of thermal coefficients of expansion. [ABSTRACT FROM AUTHOR]

Double-stranded RNA (dsRNA)-degrading enzyme (dsRNase) is one of the negative factors influencing the RNA interference (RNAi) effect in Colorado potato beetle (CPB). We have previously shown that plastid-mediated RNAi (PM-RNAi) can be utilized to control CPB. In this study, we aimed to test whether silencing dsRNase could increase the RNAi effect in CPB via PM-RNAi. We generated transplastomic potato (Solanum tuberosum) plants expressing dsRNA targeting shibire (dsSHI) of CPB. St-dsSHI plants (transplastomic plants expressing dsSHI) showed much less potent RNAi response than transplastomic potato plants expressing dsRNAs targeting CPB Shrub (St-dsSHR) or β-Actin (St-dsACT), two CPB-resistant transplastomic lines generated previously. The three types of transplastomic lines have weak (St-dsSHI), moderate (St-dsSHR) and strong (St-dsACT) resistant levels to CPB. Treatment with in vitro-synthesized dsdsRNase1/2 (a fusion dsRNA targeting dsRNase1 and dsRNase2 of CPB) led to enhanced suppression of dsRNase1 and dsRNase2 in CPB larvae fed with St-dsSHI plants and dsRNase2 in CPB larvae fed with St-dsSHR plants. St-dsSHR or St-dsSHI plants showed significantly reduced CPB larva weight or damaged area by CPB feeding. These results demonstrate that dsRNase-silencing approach could improve the effect of PM-RNAi when the silencing of target genes has weak or moderate strength of the insecticidal effects. The findings provide a new proof-of-concept to enhance crop resistance to insect herbivores to via an “RNAi-of-RNAi” approach. [ABSTRACT FROM AUTHOR]

Plastid-mediated RNA interference (PM-RNAi) has emerged as a promising strategy for pest control. Expression from the plastid genome of stable double-stranded RNAs (dsRNAs) targeted against essential insect genes can effectively control some herbivorous beetles, but little is known about the efficacy of the transplastomic approach in other groups of pest insects, especially nonchewing insects that do not consume large amounts of leaf material. Here we have investigated the susceptibility of the western flower thrip (WFT, Frankliniella occidentalis), a notorious pest in greenhouses and open fields, to PM-RNAi. We show that WFTs ingest chloroplasts and take up plastidexpressed dsRNAs. We generated a series of transplastomic tobacco plants expressing dsRNAs and hairpin RNAs (hpRNAs) targeted against four essential WFT genes. Unexpectedly, we discovered plastid genome instability in transplastomic plants expressing hpRNAs, suggesting that dsRNA cassettes are preferable over hpRNA cassettes when designing PM-RNAi strategies. Feeding studies revealed that, unlike nuclear transgenic plants, transplastomic plants induced a potent RNAi response in WFTs, causing efficient suppression of the targeted genes and high insect mortality. Our study extends the application range of PM-RNAi technology to an important group of nonchewing insects, reveals design principles for the construction of dsRNAexpressing transplastomic plants, and provides an efficient approach to control one of the toughest insect pests in agriculture and horticulture. [ABSTRACT FROM AUTHOR]

Plants optimize their growth and survival through highly integrated regulatory networks that coordinate defensive measures and developmental transitions in response to environmental cues. Protein phosphatase 2A (PP2A) is a key signaling component that controls stress reactions and growth at different stages of plant development, and the PP2A regulatory subunit PP2A‐B′γ is required for negative regulation of pathogenesis responses and for maintenance of cell homeostasis in short-day conditions. Here, we report molecular mechanisms by which PP2A‐B′γ regulates Botrytis cinerea resistance and leaf senescence in Arabidopsis (Arabidopsis thaliana). We extend the molecular functionality of PP2A‐B′γ to a protein kinase-phosphatase interaction with the defense-associated calcium-dependent protein kinase CPK1 and present indications this interaction may function to control CPK1 activity. In presenescent leaf tissues, PP2A-B′γ is also required to negatively control the expression of salicylic acid-related defense genes, which have recently proven vital in plant resistance to necrotrophic fungal pathogens. In addition, we find the premature leaf yellowing of pp2a-b′γ depends on salicylic acid biosynthesis via SALICYLIC ACID INDUCTION DEFICIENT2 and bears the hallmarks of developmental leaf senescence. We propose PP2A-B′γ age-dependently controls salicylic acid-related signaling in plant immunity and developmental leaf senescence. [ABSTRACT FROM AUTHOR]