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Soil disinfestation is an important agricultural practice to conquer soil-borne diseases and thereby ensure crop productivity. Reductive soil disinfestation (RSD) had been developed as an environmentally friendly alternative to chemical soil disinfestation (CSD). However, the differences between CSD and RSD on soil-borne pathogen suppression and fungal community structure remain poorly understood. In this work, five treatments, i.e., untreated soil (CK), CSD with 0.5 t ha−1 dazomet (DZ), RSD with 10 t ha−1 ethanol (ET), 15 t ha−1 sugarcane bagasse (SB), and 15 t ha−1 bean dregs (BD), were performed to investigate their influences on disinfestation efficiency, fungal abundance, diversity, and community structure via quantitative PCR and high-throughput sequencing. RSD-related treatments, especially the BD treatment, effectively alleviated soil acidification and salinization. The fungal abundance and microbial activity considerably increased in the BD treatment and significantly declined in the DZ treatment as compared to the CK treatment. Moreover, both CSD and RSD-related treatments significantly inhibited the population of Fusarium oxysporum and the relative abundance of genus Fusarium. Fungal community structure was notably altered by CSD and RSD practices. Furthermore, both CSD and RSD harbored a distinct unique microbiome, with the DZ treatment dominated by the genus Mortierella and BD treatment predominated by the genera Zopfiella, Chaetomium, and Penicillium. Taken together, these results indicate that the BD treatment could considerably alleviate the soil deterioration, improve soil microbial activity, and reassemble a non-pathogen unique microbiome that have more disease-suppressive agents and thus might be a promising disinfestation practice to control soil-borne disease in monoculture system. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the influence of ammonium (NH ) (0% and 50% of total nitrogen, N) in combination with calcium (Ca) on the growth of lisianthus ( Eustoma grandiflorum) in perlite cultures. Ammonium significantly improved leaf area, stem diameter, flower buds, and chlorophyll content (SPAD index) while increasing levels of Ca resulted in decreased leaf area, and chlorophyll contents. Application of NH increased dry weight (DW) of stems, leaves and flowers with a reduction in root DW. In contrast, increased Ca caused a decrease in DW of all plant parts, except flowers. Decreased photosynthesis in NH -fed plants was associated with a decrease in magnesium (Mg) and potassium (K) uptake, and an increase in phosphorus (P) and sulfur (S) uptake. The potentially deleterious effect of this nutrient imbalance was counteracted by allocating more K and Mg to the shoot and flowers. The ability of lisianthus to shift the allocation of nutrients to sensitive plant parts may explain the tolerance of this species to high NH . Ammonium was associated with decreased peroxidase and catalase activities, suggesting that plants were under oxidative stress. Plants typically respond to high NH nutrition by decreasing the uptake of Ca; however, in our study, increasing Ca and NH resulted in increased Ca uptake, reaching toxic concentrations in shoot tissues. [ABSTRACT FROM AUTHOR]

High temperatures cause rosetting and the continued vegetative growth of Eustoma grandiflorum. Eustoma requires a period of cold treatment to promote flowering. Ortholog of flowering time gene FT ( EgFT) was isolated and characterized from E. grandiflorum. The ectopic expression of EgFT significantly promotes flowering in transgenic E. grandiflorum even when grown at high (28-30 °C) temperature conditions without any cold treatment. In addition, a severe defect in stamen and carpel formation in which they are converted into sepal/petal-like structures were observed in transgenic E. grandiflorum that strongly expressed EgFT. This homeotic conversion was correlated with the upregulation of A ( EgAP1/EgFUL) and E ( EgSEP1/3) and downregulation of C ( EgAG) functional MADS box genes in transgenic E. grandiflorum. In wild-type E. grandiflorum, EgFT mRNA was detected in leaves and was expressed higher in young than in mature flower buds. In flowers, EgFT mRNA was strongly expressed in sepals, moderately expressed in petal, and was almost undetectable in stamen and carpel. This expression pattern was very similar to that found for EgAP1 and completely inverse to that found for EgAG. These results indicated that EgFT is able to promote flowering and regulate sepal/petal formation by activating the A/E genes and suppressing the C gene in E. grandiflorum. 35S::EgFT also caused early flowering in transgenic Arabidopsis. However, the flower organ formation and the expression of the Arabidopsis AG gene were not affected. Thus, the ability for EgFT to regulate EgAG expression may represent a distinct mechanism in E. grandiflorum for the regulation of flower organ formation. [ABSTRACT FROM AUTHOR]

In 2007, lisianthus ( Eustoma grandiflorum) plants with necrotic ringspots on the leaves were found in Kochi Prefecture, Japan. Tospovirus-like spherical enveloped particles with ca. 160 nm in diameter were observed with electron microscopy. The complete nucleotide sequence of the S RNA segment of the virus was determined, and phylogenetic analysis using deduced amino acid sequences of the nucleocapsid protein and the nonstructural S protein indicated that the virus is phylogenetically distinct from any known tospovirus species. The results suggest that the virus is a new member of the genus Tospovirus, in the family Bunyaviridae. The virus is the fifth distinct tospovirus occurring naturally in lisianthus in Japan. The necrotic symptoms were reproduced on lisianthus seedlings after mechanical inoculation. The host range of the virus isolate on several test plants was also examined. [ABSTRACT FROM AUTHOR]

The article discusses research on how benzyladenine (BA) can affect the quality and vase life of cut Lsianthus flowers. The study by Mahnaz Karimi and Moazam Hassanpour Asil pulse treated Lsianthus flowers in various BA concentrations in combination with 3% of sucrose and observed their vase life. Results showed that flower senescence and ethylene production of flowers were delayed with BA treatment along with decreased weight loss of the fresh flowers. BA treatement increased the concentration of anthocyanin and decreased chlorophyll degradation.

In March 1999, we found prairie gentian ( Eustoma grandiflorum) infected with powdery mildew in a greenhouse in Oita Prefecture, Japan. Morphological observation revealed that the causal fungus belongs to the mitosporic genus Oidium subgenus Pseudoidium [teleomorph: Erysiphe sensu Braun and Takamatsu (2000)]. Precise taxonomic position of the fungus, however, is uncertain due to lack of the perfect stage. We determined the nucleotide sequence of the rDNA ITS region of the fungus. Comparison of the sequence with those obtained from DNA databases of this fungal group revealed that the sequence is identical to those of powdery mildews from garden four-o'clock ( Mirabilis jalapa) and broad bean ( Vicia faba). Inoculation of an isolate from garden four-o'clock caused mildew on prairie gentian and broad bean, suggesting that the prairie gentian mildew originates from garden four-o'clock or broad bean. Molecular phylogenetic analysis indicated a close relationship of this fungus to Erysiphe baeumleri on Vicia spp. and E. trifolii on Trifolium pratense. From these results, we propose that prairie gentian mildew diverged from a Fabaceae-parasitic ancestor. [ABSTRACT FROM AUTHOR]

The responses of two lisianthus ( Eustoma grandiflorum) inbred lines and their heterotic (in vivo) F hybrid to different levels of benzyladenine (BA) and gibberellic acid (GA) were studied under in vitro conditions. Number of axillary shoots developed (NAS), main shoot length (MSL), total fresh and dry weights, and extent of callus formation were measured. The two parents differed in their response to both hormones by all parameters measured. High-parent heterosis for NAS and MSL proved to be dependent on the specific BA and GA levels. The required BA concentrations for maximum NAS and MSL for the F were higher than those required for either parent; this may be defined as a heterosis in BA-requirement for maximal in vitro response. Adding 0.25 or 1 mg/liter GA to the medium caused a considerable increase in NAS and in dry weight gain only when combined with BA. On the other hand, MSL was increased by GA addition only at 0 or 0.1 mg/liter BA, but not at 0.5 mg/liter BA. Callus formation was greatly encouraged by raising the BA level from 0 to 0.1 or 0.5 mg/liter and by the addition of GA at low BA level. Assumed differences in endogenous BA and GA levels among the genotypes studied seemed to be related to the expression of heterosis. [ABSTRACT FROM AUTHOR]

Background: Eustoma grandiflorum is a new floral crop for the international flowers market, moderately cold-tolerant annual or biennial plant. A large number of seedlings can be produced by seed propagation but the quality is not uniform due to variations in the flowering time, plant height, and the number of flowers. Propagation of Eustoma grandiflorum plant by tissue culture technique is relatively low. Inducing mutations is one of the powerful tools for breeding biotechnology. Laser mutagenesis is an easy and new tool. The goal of the present work was to investigate the influence of laser irradiation on in vitro growth, anatomy, flowering, chemicals composition, and gene mutagenesis. Results: The most of morphological, floral parameters, total chlorophyll, carotenoids, and anthocyanin pigment contents in the flower recorded increment by most treatments of laser types. The highest survival percentage of acclimatized plants (95%) and highest values of number of branches and branches length (cm) were obtained from treated plantlets by 20 min of green laser, while most of highest floral parameters, anthocyanin pigment contents in flower, and anatomical structural parameters recorded increasing using 20 min of blue laser and 20, 25 min of green and red laser, respectively. Contrary, the lowest values of photosynthetic pigments and carotenoids were obtained from 20 min of green laser. Conclusions: The current research concluded that laser irradiation has remarkable effect on plant morphology, flowering, chemical constituents, and gene mutagenesis. [ABSTRACT FROM AUTHOR]