Culture Seedlings Research Articles

Study on the Establishment of Efficient Leaf Regeneration System in ‘Yuluxiang’ Pear

The ‘Yuluxiang’ pear is a key cultivated variety in China, celebrated for its high quality. However, it exhibits a low leaf regeneration frequency of only 35.0%, which hinders its transgenic breeding process. To establish an efficient regeneration system, we utilized tissue culture seedlings of the ‘Yuluxiang’ pear and investigated various factors influencing leaf regeneration: plant growth regulators, natural organic materials, leaf wounding and positioning methods, duration of dark culture, ages and lines of plantlets, as well as culture containers. Our results indicated that the optimal medium for leaf regeneration consisted of MS supplemented with 6-BA (6-Benzyl Aminopurine) 1.5 mg/L, NAA (α-Naphthalene acetic acid) 0.4 mg/L along with 10% (v/v) coconut water. Suitable wounding involved ensuring no damage to leaves while placing the abaxial side facing down on the medium; the ideal duration for dark culture was determined to be 21 days; optimal plantlet age was found to be 20 days; both plantlet line 1 and line 2 demonstrated effectiveness; triangle bottles were identified as appropriate culture containers. In summary, we successfully established an efficient leaf regeneration system for the ‘Yuluxiang’ pear that achieved a maximum regeneration frequency of 96.70% with an average bud number of 5.15 per explant. This system also proved effective for the ‘Qiuyue’ pear, yielding a regeneration frequency of 88.89% and an average bud number of 3.44 per explant. After investigating the germination methods of 200 leaves from this screened leaf regeneration system of ‘Yuluxiang’, it was found that there were both direct and indirect regeneration methods, and the germination rate of direct and indirect regeneration was 68.00% and 70.50%, respectively. Therefore, this study also laid a solid foundation for the future genetic transformation of ‘Yuluxiang’ pear.

The Impact of Culture Time on Genistin and Genistein Accumulation in Flemingia macrophylla (Willd.) Prain Seedlings and the Differentially Expressed Genes

Background Genistein and genistin are the main active constituents of Flemingia macrophylla (Willd.) Prain and the amount of active constituents in the roots varies depending on the cultivation time. The harvesting period has a great influence on its quality, and there are fewer studies on the optimal harvesting time of F. macrophylla, which is urgently needed to explore the optimal harvesting period to improve its use value. Purpose F. macrophylla (Willd.) Prain is an important medicinal plant distributed in China. This study aimed to enhance the accumulation of active ingredients genistin and genistein in F. macrophylla, and explore the mechanism of biological synthesis of these active compounds at molecular levels. Methods Transcriptome sequencing and high-performance liquid chromatography (HPLC) technology were applied to F. macrophylla tissue culture seedlings for 30 days after culturing (DAC), 45 DAC, 60 DAC, and 75 DAC. Then, gene expression, representative active substances, and important phenotypic indexes were analyzed. Results The highest fresh weight and root thickness were attained at 45 DAC, the highest plant height at 60 DAC, and the maximum rooting rate at 75 DAC. The genistin content reached the highest level at 45 DAC, and the content of genistein reached the highest level at 30 DAC. The total content of genistin and genistein achieved the maximum levels at 45 DAC. A total of 7,735 differently expressed genes (DEGs) in the three comparable groups, including T45d vs T30d, T60d vs T30d, and T60d vs T45d, were identified. Through the Kyoto Encyclopedia Genes and Genomes (KEGG) enrichment analysis of DEGs, isoflavonoid biosynthesis and phenylpropanoid biosynthesis pathways were significantly enriched in two groups, including T45d vs T30d and T60d vs T30d. A total of 41 DEGs involved in the production of isoflavones were discovered in the three groups. Conclusion The optimism culture time for the accumulation of genistein and genistin in F. macrophylla seedlings ranged from 30 to 45 days. Forty-one DEGs in the genistein and genistin synthesis pathways were found through transcriptomics analysis. This study sheds light on the biosynthesis of genistin and genistein in F. macrophylla.

Eco-friendly Cultivation of Annual Chrysanthemum for Enhancing Seed Quality and Soil Properties

Sustainable agriculture is the cultivation of healthy soil and seedlings which are essential for producing high-quality yields that meet the nutritional needs of living organisms. The soil and its microenvironment are crucial for significantly improving plant growth and promotion of sustainable agriculture practices. This focus on sustainability aims for long-term crop and livestock production while minimizing negative environmental impacts. Therefore, for eco-friendly cultivation of annual chrysanthemum a study was carried out in the open field of the Department of Seed Science and Technology at Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan (H.P) India for two years (2019-2021). The field experiment consisted of nine different formulations of jeevamrit arranged in Randomized Complete Block Design (RCBD) with three replications for each treatment. Notably, the use of T6 (Drenching with jeevamrit @30% at 15 days interval) and T7 (Drenching with jeevamrit @35% at 15 days interval) significantly enhanced the production while also enriching the soil with the considerable increase in beneficial microbial count like bacteria, fungi and actinomycetes. Hence, this seeks to identify an environmentally friendly method to improve seed production quality in annual chrysanthemum and enhance soil nutrients.

A Comparative Transcriptome Analysis Revealing the Mechanism Underlying the Effect of Maternal Plant Age on Adventitious Rooting of Euryodendron excelsum Cuttings

Euryodendron excelsum H. T. Chang, a monotypic plant endemic to China, exhibits significant variations in adventitious root formation in cuttings across different age groups through unclear molecular mechanisms. In this study, we performed RNA-sequencing (RNA-seq) and data analysis at three stages—initial excision (S0), root primordia (S1), and emergence of adventitious roots (S2)—for lateral buds from transplanted triennial tissue culture seedlings and decennial E. excelsum plants. We identified 13,424 differentially expressed genes (DEGs) between different rooting stages and age groups, including 8216 upregulated and 5208 downregulated genes. A Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that the S1 and S2 DEGs identified were mainly involved in phenylpropanoid biosynthesis, plant hormone signal transduction, plant–pathogen interactions, biosynthesizing various secondary plant metabolites, and starch and sucrose metabolism. Key auxin-pathway genes were expressed at significantly higher levels in culture seedlings than in adult plants, as were WUSCHEL-related homeobox and LATERAL ORGAN BOUNDARIES DOMAIN genes (related to adventitial root growth and development), which together promote the formation, growth, and development of adventitial root primordia. The dysregulated expression of 15 DEGs identified by RNA-seq were verified via real-time quantitative polymerase chain reaction analysis. This study investigates the morphological processes of adventitious root formation in cuttings of E. excelsum of different ages, and the potential molecular mechanisms involved. Our finding provides a basis for research on cutting propagation, conservation applications, and optimization of tissue culture for E. excelsum, and may help improve the rooting rate of E. excelsum cuttings.

Paenibacillus oenotherae W2-3 degraded Welan gum to produce growth-promoting oligosaccharides.

Based on the biodegradation of Welan gum, this paper studies the properties of Welan gum degrading enzymes, degradation rules, and the application of Welan gum oligosaccharides. In order to study the biodegradation of Welan gum, a strain W2-3 capable of degrading Welan gum, was isolated from soil and identified as Paenibacillus sp. The properties of Welan gum degrading enzymes, degradation rules, and the application of Welan gum oligosaccharides were studied. After degradation, the average molecular weight of Welan gum oligosaccharides could be degraded to 500Da, and the molecular weight distribution range was wide. Through the hydroponic culture of barley seedlings, it was proved that the degradation products of Welan gum had a positive effect on plant growth. The results showed that Welan gum oligosaccharides could significantly increase the root length, plant height, and fresh weight of barley, and could be used as a growth regulator in agricultural production.

Establishment and Validation of an Efficient Agrobacterium Tumefaciens-Mediated Transient Transformation System for Salix Psammophila.

Salix psammophila, C. Wang & Chang Y. Yang, a desert-adapted shrub, is recognized for its exceptional drought tolerance and plays a vital role in ecosystem maintenance. However, research on S. psammophila has been limited due to the lack of an efficient and reliable genetic transformation method, including gene functional studies. The Agrobacterium-mediated transient overexpression assay is a rapid and powerful tool for analyzing gene function in plant vivo. In this study, tissue culture seedlings of S. psammophila were utilized as the recipient materials, and the plant expression vector pCAMBIA1301, containing the GUS reporter gene, was transferred into the seedlings via an Agrobacterium-mediated method. To enhance the efficiency of the system, the effects of secondary culture time, Agrobacterium concentration, infection time, and co-culture duration on the transient transformation efficiency of S. psammophila were explored. The optimal combination for the instantaneous transformation of S. psammophila tissue culture seedlings mediated by Agrobacterium was determined as follows: a secondary culture time of 30 d, a value of OD600 of 0.8, an infection time of 3 h, and a co-culture duration of 48 h. Subsequently, the effectiveness of the transformation system was validated using the S. psammophila drought response gene SpPP2C80. To further confirm the accuracy of the system, SpPP2C80-overexpressing Arabidopsis was constructed and drought resistance analysis was performed. The results were consistent with the transient overexpression of SpPP2C80 in S. psammophila tissue culture seedlings, indicating that this system can be effectively employed for studying gene function in S. psammophila. These findings provide essential information for investigating gene function in non-model plants and pave the way for advancements in molecular biology research in S. psammophila.

The effect of long-term storage on the viability and properties of Alternaria alternata, Bipolaris sorokiniana and Fusarium solani strains of the Phytopathogenic Microorganisms State Collection of ARRIP

Relevance. Under conditions of prolonged storage of fungi on a nutrient agar medium, their pathogenic properties are gradually lost. Preservation of collection material with unchanged pathogenic properties is necessary for correct research, including the development of biological protection methods, monitoring of pathogen development dynamics, assessment of their virulence and aggressiveness, choice of selection material.Materials and Methods. The ability to the resumption of full-fledged species characteristics on the culture nutrient agar medium after long-term storage of the biomaterial in the form of a lyophilizate under conditions of low positive +4°C and ultra-low temperatures of -80°C of Alternaria alternata (Fr.) Keissl., Bipolaris sorokiniana Shoemaker and Fusarium solani (Mart.) Sacc. strains stored in the State Collection of Phytopathogenic Microorganisms of the All-Russian Research Institute of Phytopathology (ARRIP) was studied. The viability of fungi was judged by their ability to form spore-forming colonies on a nutrient medium, pathogenicity and phytotoxicity by the reaction of test culture seedlings to the effects of spore suspensions and culture fluid filtrates.Results. Long-term storage of Alternaria alternata, Bipolaris sorokiniana and Fusarium solani strains in a freeze-dried state, both at low and ultra-low temperatures, did not adversely affect their viability. On the 14th day of culture on a nutrient medium, fungal strains formed sporulating colonies comparable to the control variants. Comparison of pathogenicity signs in fungal strains before the experiment and after storage did not reveal significant differences between the variants. When studying the effect of the culture liquid filtrates of fungal strains on the development of the test culture, a differentiating effect of the storage regime at +4oC was established, while under ultra-low temperatures the results in the variants practically did not differ.Conclusion. The results of the study were showed that the lyophilization of biomaterial,including imperfect species of fungi for long-term storage at low positive and ultra-low temperatures is relevant and in demand in many scientific and industrial institutions.

The fungal effector AaAlta1 inhibits PATHOGENESIS-RELATED PROTEIN10-2-mediated callose deposition and defense responses in apple.

Apple leaf spot, caused by Alternaria alternata f. sp mali (ALT), poses a substantial threat to the global apple (Malus × domestica Borkh.) industry. Fungal effectors promote pathogen infestation and survival by interfering with plant immune responses. In our study, we investigated the secretion of effector proteins by the virulent ALT7 strain. Using mass spectrometry, we identified the effector AaAlta1, which belongs to the Alt a 1 protein family (AA1s). Further analysis confirmed that ALT7 secretes AaAlta1. AaAlta1 knockdown mutants displayed reduced pathogenicity in apple tissue culture seedlings, while overexpression strains exhibited enhanced pathogenicity compared to the wild-type ALT7 strain. Using immunoprecipitation followed by mass spectrometry, we isolated pathogenesis-related protein 10-2 (PR10-2) as an interaction partner of AaAlta1 in apple. Knockdown mutants of AaAlta1 showed increased PR10-2-mediated callose deposition in apple, a critical plant defense response. The enhanced defense responses in apple substantially reduced their susceptibility to infection by these ALT7 mutants. Our findings delineate an infection strategy whereby ALT7 secretes AaAlta1 to suppress PR10-2, thereby circumventing the apple defense system.

Tannins and copper sulphate as antimicrobial agents to prevent contamination of Posidonia oceanica seedling culture for restoration purposes.

Seed-based restoration methods are increasingly recognized as a relevant tool contributing to halt and reverse the loss of seagrass meadows while providing genetic and evolutionary benefit for the conservation of these habitats. Ad-hoc protocols aimed at maximizing the survival of plantlets obtained from seeds in cultivation systems are therefore required. Previous trials of seedling culture of Posidonia oceanica, the dominant seagrass of the Mediterranean Sea, recorded up to 40% loss due to mould development. In this study we aim to (i) identify the putative causal agents of seed decay and (ii) test the efficacy of copper sulphate (0.2 and 2 ppm) and of tannin-based products derived from chestnut, tara and quebracho in reducing seed and seedling decay, while assessing possible phytotoxic effects on plant development. Halophytophthora lusitanica, H. thermoambigua and a putative new Halophytophtora species were identified as possible causal agents of seed loss. The antimicrobial agents (copper and tannins) reduced seed contamination by 20%, although copper sulphate at 2 ppm strongly inhibited the root growth. Among tannins, chestnut and tara reduced seeds germination by up to 75% and decreased shoot and root development, while quebracho showed a less severe phytotoxic effect. The use of copper sulphate at 0.2 ppm is therefore recommended to prevent P. oceanica seedling loss in culture facilities since it reduces seed contamination with no phytotoxic effects. Our results contribute to improving the seedling culture of one the key species of the Mediterranean Sea, increasing propagule availability for restoration purposes.

Recognition of Maize Tassels Based on Improved YOLOv8 and Unmanned Aerial Vehicles RGB Images

The tasseling stage of maize, as a critical period of maize cultivation, is essential for predicting maize yield and understanding the normal condition of maize growth. However, the branches overlap each other during the growth of maize seedlings and cannot be used as an identifying feature. However, during the tasseling stage, its apical ear blooms and has distinctive features that can be used as an identifying feature. However, the sizes of the maize tassels are small, the background is complex, and the existing network has obvious recognition errors. Therefore, in this paper, unmanned aerial vehicle (UAV) RGB images and an improved YOLOv8 target detection network are used to enhance the recognition accuracy of maize tassels. In the new network, a microscale target detection head is added to increase the ability to perceive small-sized maize tassels; In addition, Spatial Pyramid Pooling—Fast (SPPF) is replaced by the Spatial Pyramid Pooling with Efficient Layer Aggregation Network (SPPELAN) in the backbone network part to connect different levels of detailed features and semantic information. Moreover, a dual-attention module synthesized by GAM-CBAM is added to the neck part to reduce the loss of features of maize tassels, thus improving the network’s detection ability. We also labeled the new maize tassels dataset in VOC format as the training and validation of the network model. In the final model testing results, the new network model’s precision reached 93.6% and recall reached 92.5%, which was an improvement of 2.8–12.6 percentage points and 3.6–15.2 percentage points compared to the mAP50 and F1-score values of other models. From the experimental results, it is shown that the improved YOLOv8 network, with high performance and robustness in small-sized maize tassel recognition, can accurately recognize maize tassels in UAV images, which provides technical support for automated counting, accurate cultivation, and large-scale intelligent cultivation of maize seedlings.

Comparative Transcriptome Analysis of Sexual Differentiation in Male and Female Gonads of Nao-Zhou Stock Large Yellow Croaker (Larimichthys crocea).

The Nao-zhou stock large yellow croaker (Larimichthys crocea) is a unique economic seawater fish species in China and exhibits significant dimorphism in both male and female phenotypes. Cultivating all-female seedlings can significantly improve breeding efficiency. To accelerate the cultivation process of all female seedlings of this species, it is necessary to deeply understand the regulatory mechanisms of sexual differentiation and gonadal development. This study used Illumina high-throughput sequencing to sequence the transcriptome of the testes and ovaries of Nao-zhou stock large yellow croaker to identify genes and molecular functions related to sex determination. A total of 10,536 differentially expressed genes were identified between males and females, including 5682 upregulated and 4854 downregulated genes. Functional annotation screened out 70 important candidate genes related to sex, including 34 genes highly expressed in the testis (including dmrt1, foxm1, and amh) and 36 genes highly expressed in the ovary (including gdf9, hsd3b1, and sox19b). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis found that differentially expressed genes were significantly enriched in nine signaling pathways related to sex determination and gonadal development, including steroid hormone biosynthesis, MAPK signaling pathway, and the TGF-beta signaling pathway. By screening sex-related differentially expressed genes and mapping protein-protein interaction networks, hub genes such as dmrt1, amh, and cyp19a1a were found to be highly connected. The expression levels of 15 sex-related genes, including amh, dmrt1, dmrt2a, foxl1, and zp3b, were determined by qRT-PCR and RNA sequencing. This study screened for differentially expressed genes related to sex determination and differentiation of Nao-zhou stock large yellow croaker and revealed the signaling pathways involved in gonad development of male and female individuals. The results provide important data for future research on sex determination and differentiation mechanisms, thereby providing a scientific basis for the cultivation of all-female seedlings.

Hydroponic Culture of Rice Seedlings for Stress Response Assay.

The major environmental factors limiting rice growth and production are osmotic stresses such as drought and high salinity. High osmotic stresses directly disrupt cellular activities, leading to plant growth retardation or death. Plants have various response mechanisms to survive under such stresses. Understanding rice's stress response mechanisms is necessary to enhance the osmotic stress tolerance of rice. However, assessing specific physiological responses to osmotic stresses is difficult because multiple environmental factors affect rice growth. Here, we describe a simple method for analyzing the osmotic stress responses of rice plants using a hydroponic culture system. This method allows comprehensive gene expression and phenotypic analyses under osmotic stress conditions in rice. Various osmotic stress conditions and samples can be tested simultaneously because this method is small-scale. In addition, the procedure is easy, and highly reproductive results can be obtained.

Assembly of phyllosphere bacterial community with PsnWRKY70 in poplar

Plant microbiome plays an important role in growth and development, biotic and abiotic stresses, and genotype is one of the key factors in shaping the microbiome. In this study, the effect of PsnWRKY70 on the synthetic bacterial community of poplar was investigated. To explore the assembly mechanism of poplar phyllosphere bacteria. we used 39 strains of bacteria isolated from the phyllosphere of poplar to construct a synthetic bacterial community. The leaves of aseptic poplar tissue culture seedlings were inoculated with synthetic bacterial community, and the bacterial communities of poplar leaves inoculated with synthetic bacterial community for 0 d, 5 d, 10 d and 15d were sequenced for 16 s. Bacterial community composition, PCoA, and Lefse analyses were performed. The results showed that the bacterial community in the phyllosphere of poplar tended to be in a stable equilibrium state after inoculation with the synthetic bacterial community. The results of β diversity analysis showed that there were significant differences in the bacterial community structure of OE, RE and WT leaves at 5d and 10 d after inoculation with Syncom. It is mainly composed of Methylobacteriaceae, Enterbacteriaceae, Agrobacterium, Rhizobium, Pseudoxanthomonas and Stenotrophomonas. The results of differential bacterial analysis showed that Paracoccus, Arthrobacter and Rhodococcus had higher relative abundance and stability in OE line. PsnWRKY70 gene plays an important role in recruiting Paracoccus, Arthrobacter and Rhodococcus strains in poplar leaves.

One New Host Records of Apiospora arundinis From Lactarius vividus

In this investigation, morphological traits and phylogenetic analyses of multiple genes, including ITS, 28S, tub2, and tef1, were employed to classify a companion fungus extracted from the fresh fruiting bodies of Lactarius vividus in China. The fungus was identified as Apiospora arundinis, marking the first instance of its isolation from a mushroom. Subsequent research into its biological characteristics revealed that the mycelium was the optimal condition of 30 oC, pH7 and grew well in medium containing soluble starch and peptidic sugars. It was also observed that this fungus was resent in the fruiting bodies of Lactarius vividus, and its hyphal growth was influenced by temperature, pH, and media composition. These findings lay a foundation for additional research and practical applications of Apiospora arundinis, which are of great significance for the storage and preservation of Lactarius vividus, guiding the cultivation of mycorrhizal seedlings, and exploring the mechanism and mechanism, but the specific principles need to be further explored.

Effect of Different Basal Media and Organic Supplements on In Vitro Seedling Development of the Endangered Orchid Species Dendrobium moniliforme (L.) Swartz

The orchid Dendrobium moniliforme faces endangerment due to habitat loss and illegal harvesting, necessitating the development of an optimized artificial propagation system to aid conservation and reintroduction efforts. This study evaluated the effects of three plant growth media, namely Murashige and Skoog (MS), Hyponex, and Orchid Maintenance Medium (OMM) (P668), and various organic additives (apple homogenate, banana homogenate, and coconut water) on the in vitro seedling growth of D. moniliforme. The results reveal that, in early postgermination stages, seedlings achieve maximum growth in the Hyponex medium, with a fresh weight (92 mg) and root length (2.7 cm) approximately 20-fold greater than those in the MS medium and OMM. After 6 months, for seedlings grown in MS medium and OMM with banana (50 g·L−1), the mean fresh weights were 29 and 107 mg, respectively; however, the highest biomass was observed in seedlings grown in the Hyponex medium with coconut water (50 mL·L−1), exhibiting a mean fresh weight of 201 mg. This study highlights Hyponex medium with coconut water as the most effective combination for promoting D. moniliforme growth and identifies suitable organic supplements for the in vitro cultivation of seedlings from asymbiotic seed culture. This propagation system offers valuable technical support for the mass production and conservation of this epiphytic orchid.

Refinement and Enhancement of Agrobacterium-Mediated Transient Transformation for Functional Gene Examination in Mulberry (Morus L.)

Background: Mulberry (Morus L.), a vital perennial woody plant with significant economic importance, is utilized for silkworm rearing, human consumption and medicinal use. The availability of mulberry’s whole-genome sequencing data has underscored the demand for an effective, user-friendly, and high-throughput protocol to facilitate the elucidation of gene functions. Methods and Results: In this investigation, we established a transient transformation approach using Agrobacterium tumefaciens-mediated sonication followed by vacuum infiltration in mulberry tissue culture seedlings. Simultaneously, we optimized the transformation conditions, including mulberry genotypes, A. tumefaciens strain, acetosyringone concentration, bacterial density, sonication time, and days after agroinfiltration. These optimizations aimed to achieve heightened transformation efficiency, employing GFP as a reporter gene to monitor transformation events. The optimized method included the use of an infiltration medium (10 mM MgCl2, 10 mM MES (2-(N-morpholino)ethanesulfonic acid sodium salt), 150 μM acetosyringone, and OD600 0.5 of A. tumefaciens LBA4404) supplemented with the surfactant 0.02% Silwet L-77, with 20 s sonication followed by 20 min vacuum infiltration (0.07 MPa). Among the four mulberry genotypes, ‘Taiguo’ was the most responsive genotype and produced the highest levels of GFP expression at 7 d after infiltration. Furthermore, the optimized transient transformation approach has been proven to be successfully applicable for transiently overexpressing MaANS and MaDFR in mulberry fruits of ‘Taiguo’, in vitro, which distinctly enhanced fruit coloring and significantly increased anthocyanin accumulation, respectively. Conclusions: In summary, we devised a dependable, stable and highly efficient transient transformation approach suitable for rapid gene function examination in mulberry leaves and fruits, in vitro.

In vitro photoautotrophic cultivation of Melocactus zehntneri: insights from allometric characteristics from germination to acclimatization

Melocactus zehntneri is a species of ornamental relevance suffering anthropogenic pressures, putting its preservation at risk. Thus, alternatives for propagating and conserving this species are needed. This study evaluated the effect of photoautotrophic cultivation of M. zehntneri to produce plants well acclimated to natural conditions. The seeds underwent different imbibition times before in vitro germination. Besides the growth room, a greenhouse hosted the photoautotrophic cultivation of seedlings. Vermiculite replaced agar in the culture medium. The imbibition pre-treatment in distilled water and the growth environments affected some parameters linked to germination. The greenhouse provided better characteristics for plants grown in vitro and for acclimatization than those kept in the growth room. Plants cultivated and acclimated ex vitro in a greenhouse photoautotrophic environment showed improved characteristics regarding ornamental significance.

Research of salt tolerance of genetically modified wheat plants with an additional copy of the ornithine-Δ-aminotransferase gene

Aim. To investigate the level of resistance to salt stress of T3 and T4 seed generation plants of genetically modified wheat (Triticum aestivum L.) with an additional copy of the ornithine-δ-aminotransferase (oat) gene and their original genotypes. Methods. Determination of the content of free L-proline (Pro) and physiological and morphometric parameters. Results. The level of Pro was studied and the morphometric and growth parameters of the offspring of transgenic plants and their original forms under normal / stress conditions were analyzed. Conclusions. T3 and T4 wheat plants under salinity conditions had a higher percentage and higher rate of seed germination compared to the original genotypes. During in vitro cultivation of seedlings, a stress state was observed at doses of 250 and 300 mM NaCl, at which the percentage of survival of transgenic variants was 83.3, non-transgenic only 33.3. Under conditions of in vivo salt stress, T3 and T4 plants had taller shoots and longer roots compared to the original forms. The survival rate of genetically modified plants was ~ 90 %, non-transgenic plants about 60 %. There was no significant difference in the accumulation of free L-proline between the investigated plant variants. It increased in transgenic seedlings on the 21st day of stress under conditions of artificially simulated salinity.

1. The seaweed seedling culture technique utilizing feeding behavior of herbivorous fish

1. The seaweed seedling culture technique utilizing feeding behavior of herbivorous fish

Livestock and poultry waste compost as an amendment in medium for pumpkin seedlings

This research evaluated cow dung compost (CDC), goose dung compost (GDC), and duck dung compost (DDC) as peat addition in growing media used for the production of pumpkin seedlings. Commercial substrate (peat: vermiculite: perlite=3:1:1, v/v) was used as the control (CK). The partial addition in peat of each waste compost in the mixtures were 10%, 20%, and 30% (v/v). The results showed that all compost in mixtures increased bulk density, total porosity, electrical conductivity, and mineral content, but negatively affected the pH and organic matter of the growing media compared to CK. CDC in mixture increased ventilation porosity and gas-water ratio and decreased water-holding porosity compared to CK, which was the opposite of the effect of GDC and DDC. The mixtures elaborated with GDC showed better growth, biomass, gas exchange parameters, and physiological indicators of seedling plants than other treatments in varying degrees, which depended on the additional amount of GDC. DDC inhibited plant growth and gas exchange parameters, especially in high addition rate; however, it had a slight promotion effect on chlorophyll content and quality because DDC was rich in minerals. GDC was better than CDC and DDC as a partial addition for peat in the cultivation of pumpkin seedlings.