Aims: This study aimed to isolate and evaluate the indigenous fluorescent Pseudomonas spp. with bio-control potential against Rhizoctonia solani and promoting growth in chilli seedlings. Methodology: A total of 120 fluorescent bacterial were isolated from the healthy chilli rhizosphere soil from the seven major chilli cultivation localities in Terengganu, Malaysia. Only 115 Gram negative fluorescent isolates were further invitro screened for antagonistic activities against R. solani and plant growth-promoting properties. The 50 most effective fluorescent Pseudomonads antagonist against R. solani with minimum percentage inhibition of radial growth (PIRG) of 65% were selected. Hierarchical cluster analysis was further conducted with two dendrograms derived from SPSS Statistic 20 to facilitate the comparison between these 50 isolates for antagonistic and growth-promoting properties. A total of 40 fluorescent isolates within the most potential cluster were further selected and identified using 16S rRNA sequencing. Thirty four fluorescent isolates were identified as Pseudomonas spp. and six isolates as Burkholderia spp. The top 13 ranked fluorescent Pseudomonas spp. from the scoring index were evaluated for seed germination and vigor index in chilli seedlings. There was no significant difference in germination rate between fluorescent Pseudomonas inoculated with control. However, vigor index of chilli seeds pre-inoculated with fluorescent P. putida (B5C1), P. aeruginosa (B3C56) and P. putida (B5C7) were significantly increased with 4684.9, 4657.3 and 4401.0 over control (P ≤ 0.05). Conclusion, significance and impact of study These selected fluorescent isolates: P. putida (B5C1), P. aeruginosa (B3C56) and P. putida (B5C7) have the potential to be developed as biofungicide against R. solani and as growthpromoter in chilli production system.
Pseudomonas fluorescens ; Rhizoctonia ; Seedlings

To investigate the adaptive mechanism of Notopterygium incisum to water changes, one-year-old seedlings were used as test materials. The characteristics of growth, physiology, and active ingredients of N. incisum were studied at different soil water content by pot experiments. The result showed that: ①The water content at 100% field capacity is conducive to the growth and accumulation of biomass of N. incisum. The leaf length, petiole length, petiole diameter, root diameter, root length and biomass of underground dry of N. incisum were all significantly increased at the 100% field capacity, and they slightly declined at 70% field capacity. 20% field capacity could not provide the necessary water to growth of N. incisum, all N. incisum withered and died. ②With the extension of moisture treatment time, the relative content of chlorophyll (SPAD) in leaves and the activity of peroxidase (POD) in rhizome showed a trend of increasing firstly, decreasing then; the tendency of activity of superoxide dismutase (SOD) in rhizome increased; the content of malondialdehyde (MDA) in rhizome decreased firstly and increased then;. For the late test, the SPAD value, the activity of POD and SOD in N. incisum at the 40% field capacity were lower than 70% field capacity and 100 field capacity, while the content of MDA in rhizome were higher than 70% field capacity and 100% field capacity. ③ At 70% field capacity, the active ingredients accumulated most in the N. incisum. At the 70% field capacity, the notopterol and isoimperatorinwerehigher than100 field capacity and 40 field capacity. In summary, the soil water content at 70%-100% field capacity would contribute to the growth and accumulation of active ingredients of N. incisum.
Apiaceae ; Chlorophyll ; Seedlings ; Soil ; Water

This study aimed to investigate differences in ectomycorrhizal (ECM) fungal communities between disturbed sites and undisturbed old forest sites. ECM root tips of Pinus densiflora were collected from 4 sites disturbed by human activities and 3 undisturbed old forest sites adjacent to the disturbed sites. Results in this study showed that the number of ECM root tips, species diversity, and number of species were significantly higher in the disturbed sites than in the undisturbed sites, suggesting that the ECM fungal community structure was affected by the degree of disturbance.
Human Activities ; Meristem ; Pinus ; Seedlings

Aconitum is a kind of important medicinal plant, which has been used in China for more than 2 000 years, with both a good medicinal and ornamental value. However, due to the lack of effective breeding methods and low seed and root propagation coefficients, the comprehensive development and utilization of Aconitum were greatly restricted. Tissue culture is an important basis for seed selection, germplasm conservation and genetic engineering. Therefore, this paper summarized the research on tissue culture of Aconitum, put forward the main problems and corresponding countermeasures, and provided important references for accelerating the seedling breeding of Aconitum and conducting the basic research of molecular biology.
Aconitum ; China ; Plant Breeding ; Plants, Medicinal ; Seedlings

Forty-three annual Citrus aurantium grafted seedlings from Chongqing, Sichuan, Hunan, Jiangxi and other main producing areas were collected, and the plant height, rootstock diameter, scion diameter, root length, root diameter, lateral root number, root breadth, branch number, branch length, green leaf number, leaf length, leaf width, thorns and other indicators were measured. Through the K-cluster analysis of SPSS 19.0 software, the classification standards were obtained. Combined with the production practice, plant height, scion diameter and branch number were taken as the quality classification indexes of C. aurantium seedlings(annual grafted seedlings), and three classification standards were established. If it does not meet the three-level standard, it is unqualified seedling and cannot be used as seedling. It is suggested to use the first and second level seedlings in production.
Citrus ; Plant Leaves ; Plant Roots ; Seedlings

Wilt disease is a major disease of cultivated Salvia miltiorrhiza, which is caused by Fusarium oxysporum. Since the infection process of F. oxysporum in plants is affected by environment factors, this study was conducted to reveal the relationship between disease severity and concentration of the pathogen in plants in the infection process of F. oxysporum in seedlings of S. miltiorrhiza by pot experiments and to reveal the effects of temperature and humidity on the infection process. The results showed that, after inoculation of S. miltiorrhiza seedlings with F. oxysporum, the pathogen in different parts was detected at different time, and it was first detected in substrates. With the continuous propagation of the pathogen(4-5 d), it gradually infected the roots and stems of the seedlings, and the plants had yellowing leaves and withering. The number of the pathogen reached the maximum in each part after 7-8 d, and then gradually decreased in the later stage of the disease. The concentration of the pathogen in substrates, roots and stems of S. miltiorrhiza showed a trend of decreasing after increasing with the aggravation of the disease and reached the maximum in the samples of moderate morbidity, while the concentration in the samples of severe morbidity decreased. In addition, the infection of F. oxysporum in seedlings of S. miltiorrhiza was affected by temperature and humidity. The suitable temperature was 25-30 ℃ and the suitable humidity was 80%-90%. This study could provide guidance for the experiments on pathogenicity of F. oxysporum, screening of biocontrol bacteria and controlling of wilt.
Seedlings/microbiology* ; Salvia miltiorrhiza ; Temperature ; Humidity ; Fusarium

Toxicity of the fungicide Flutolanil was in vitro tested against 20 isolates of Macrophomina phaseolina and cotton seedlings of ten commercial cotton cultivars. The isolates were recovered from roots of cotton plants obtained from different cotton-growing areas in Egypt. Most of the tested isolates were sensitive to Flutolanil; however, they varied in sensitivity. Twenty-five percent of the isolates were highly sensitive where IC50 ranged from < 1 to 5.1 microg/ml, 20% of the isolates were sensitive where IC50 ranged from 15 to 30 microg/ml, 45% of the isolates were moderately sensitive where IC50 ranged from 46 to 58.5 microg/ml, and 10% of the isolates were not much sensitive (tolerant) where IC50 was > 100 microg/ml. Flutolanil was very safe on both shoots and roots of the tested cultivars (IC50 > 100 microg/ml). Treating cotton seeds with Flutolanil resulted in highly significant (P < 0.01) reductions in pathogenicity of 18 isolates and a significant reduction (P < 0.05) in pathogenicity of isolate M29. M1 was the only isolate, which was insensitive to the application of Flutolanil. In vivo toxicity to Flutolanil was not correlated with its in vitro toxicity. However, a highly significant correlation (r = 0.60, P < 0.01) was observed between pathogenicity of isolates and the in vivo toxicity of the fungicide.
Egypt ; Gossypium ; Inhibitory Concentration 50 ; Seedlings ; Virulence

This study was conducted to investigate the different effects of ectomycorrhizal fungal (ECMF) species on the growth of seedlings of Pinus densiflora, and the effects of ECMF diversity on plant productivity. A total of five species of ECMF were isolated from root tips of pine seedlings collected from Mt. Songni and used as inocula. Pots containing pine seedlings were inoculated with either a single ECMF species or a mixture of five ECMF species. All of the seedlings formed ECM on their roots except for the control plants. The pine seedlings' growth responses varied by the different ECMF species. Also, pine seedlings inoculated with a mixture of five ECMF species showed the highest growth response. The results of the study suggest that the colonization of diverse species of ECMF will increase plant productivity, and the selection of suitable ECMF species could be an important factor for plant growth.
Colon ; Efficiency ; Fungi* ; Meristem ; Pinus* ; Plants ; Seedlings*

Farfugium japonicum is used in traditional medicine and as an edible herb in China and Korea. In July 2013, leaf spots were observed in F. japonicum seedlings at Ulleung Island, Gyeongsangbuk Province, Korea. Early symptoms on the leaf adaxial surface included roughly circular yellow spots that later developed brown, necrotic centers. The aecia were hypophyllous, cupulate, yellowish, 180~430 microm in diameter, clustered, and erumpent with a peridium with a recurved margin. The aeciospores were globoid, 14~17 x 13~16 microm, light yellow or colorless, and densely verrucose. The 28S rDNA sequence of the isolate was identical to each other and shared 99% identity with Puccinia caricis. This is the first report of rust caused by P. caricis in F. japonicum in Korea or elsewhere in the world.
China ; DNA, Ribosomal ; Korea* ; Medicine, Traditional ; Seedlings

Seed quality plays an important role in the agricultural and animal husbandry production, the effective utilization of genetic resources, the conservation of biodiversity and the restoration and reconstruction of plant communities. Seed aging is a common physiological phenomenon during storage. It is a natural irreversible process that occurs and develops along with the extension of seed storage time. It is not only related to the growth, yield and quality of seed and seedling establishment, but also has an important effect on the conservation, utilization and development of plant germplasm resources. The physiological mechanisms of seed aging are complex and diverse. Most studies focus on conventional physiological characterization, while systematic and comprehensive in-depth studies are lacking. Here we review the recent advances in understanding the physiology of seed aging process, including the methods of seed aging, the effect of aging on seed germination, and the physiological and molecular mechanisms of seed aging. The change of multiple physiological parameters, including seed vigor, electrical conductivity, malondialdehyde content and storage material in the seed, antioxidant enzyme activity and mitochondrial structure, were summarized. Moreover, insights into the mechanism of seed aging from the aspects of transcriptome, proteome and aging related gene function were summarized. This study may facilitate the research of seed biology and the conservation and utilization of germplasm resources.
Germination ; Plants ; Proteome ; Seedlings ; Seeds/genetics*