Promotion of stipe elongation in Flammulina velutipes by a diffusate from excised lamellae supplied with nutrients

1976 ◽  
Vol 54 (12) ◽  
pp. 1306-1315 ◽  
Author(s):  
Hans E. Gruen

Flammulina velutipes fruit bodies were grown on partly decayed Populus tremuloides sawdust supplemented with wheat bran and malt extract. In each culture there was a gradation in fruit body size, which served to select test specimens at an early stage of growth. Diffusates collected in agar blocks were applied on the apex of decapitated stipes. Plain agar and dilute potato dextrose agar (PDA/2) alone had the same slight effect on growth. Lamellae placed on plain agar caused limited growth promotion. Lamellae on PDA/2 gave 100–150% more growth promotion than on plain agar during early development, but the activity decreased to zero during the middle of the stage of rapid elongation. Lamellae of that age had no effect on young stipes and the older stipes were insensitive to diffusate from young lamellae. Very small amounts of lamellae promoted stipe elongation. Potato extract alone did not stimulate production of the lamellar diffusate and glucose was less effective than the two nutrients combined. A delay of 2 h in applying lamellar diffusate reduced stipe elongation, and there was no response after 12 h delay. Pilear trama did not produce growth-promoting diffusate.

1972 ◽  
Vol 50 (4) ◽  
pp. 803-818 ◽  
Author(s):  
Hans E. Gruen ◽  
Sheue-heng Wu

Isolated Flammulina velutipes fruit bodies were cultured under sterile conditions with the cut base immersed in water or solutions. Stipe elongation on water was only 6% of normal for fruit bodies isolated at 1.1–2.0 cm length, 19% at 5.1–6.0 cm, and the same as for fruit bodies attached to mycelium at 9.1–10.0 cm. Fruit bodies not immersed in water grew less in a saturated atmosphere than those in water. The mycelium must supply other substances than water for normal elongation during about two-thirds of the growth period, and only water thereafter. Isolated fruit bodies fed with filtered glucose, trehalose, sucrose, or mannitol grew better than on water. Maltose and fructose increased elongation only slightly, and sorbose had no effect. Potato extract, yeast extract, and casein hydrolysate gave no or very little growth promotion, but addition of glucose strongly increased growth on the natural extracts compared to glucose alone. Of 21 amino acids added separately to glucose, only asparagine, hydroxyproline, arginine, and to a lesser extent glutamine, stimulated growth of isolated fruit bodies. Growth was not promoted by pure asparagine, glutamine, and serine, or by thiamin or indoleacetic acid. Growth was inhibited by urea, ammonium nitrate, and ammonium tartrate with or without glucose.Growth promoting substances were most effective in young fruit bodies and except for glucose the promotion disappeared in fruit bodies isolated at 6.1–7.0 cm length, which corresponds to the end of the period of rapid elongation. Apical portions of fruit bodies with caps grew better on glucose than whole fruit bodies. Growth of decapitated isolated stipes was not promoted by nutrients.


1979 ◽  
Vol 57 (10) ◽  
pp. 1131-1135 ◽  
Author(s):  
Hans E. Gruen

Flammulina velutipes fruit bodies only grew normally if the pileus remained on the stipe until the end of rapid elongation when about 80% of the final length had been reached. During the same period lamellae alone increased stipe growth significantly compared with total decapitation. The stipes attained three-quarters of the length of intact fruit bodies with only about one-third of all lamellae. Near the end of the normal growth period, the stipe became independent of the pileus and lamellae. Small amounts of lamellae excised during rapid elongation produced diffusate in dilute potato glucose agar which promoted growth of decapitated stipes of the same age. The activity could be detected when fruit bodies had completed two-thirds of their normal growth but was much less than at the onset of rapid elongation. Tests of diffusates from young and old lamellae on stipes of different ages showed that the declining influence of lamellae in aging fruit bodies is associated both with decreasing production of the growth-promoting factor and decreasing response of stipes to an external supply of active diffusate. Neither pilear context nor any part of young or old stipes released growth-promoting diffusate.


Author(s):  
Lygia Vitória Galli Terasawa ◽  

Maize (Zea mays L.) culture has a great importance in several countries, especially in Brazil the third-largest world producer. The increase in maize production has been achieved with a high use of fungicide; however, in view of a more sustainable agriculture plant growth promoting bacteria have been explored aiming for the replacement of chemical fertilizers and biological control. In this study, we investigated the bacterial community isolated from maize roots in order to evaluate their capacity of growth promotion as well as of inhibition of fungal species associated with maize leaf diseases. All isolates evaluated were positive for at least one of the parameters evaluated-growth promotion, enzymatic production or bio control. The best results were observed for Enterobacter sp. LGMB221 and Bacillus sp. LGMB242 that showed the high potential for growth promotion, acting in the early stage of maize seedlings development. Bacillus sp. LGMB152 showed the best enzymatic results, indicating that it might play a role against pathogens, a premise supported by the antagonist activity observed. The next steps involve evaluations under field conditions to confirm if these isolates have biotechnological potential as inoculants for the maize crop. In addition, we suggest that Enterobacter strains LGMB221 and LGMB235 and Escherichia strain LGMB159 might represent new species, indicating the high diversity of bacteria in maize rhizosphere that remains to be determined.


1995 ◽  
Vol 42 (11) ◽  
pp. 907-912 ◽  
Author(s):  
Takao TERASHITA ◽  
Makoto NAWAMA ◽  
Kentaro YOSHIKAWA ◽  
Jiko SHISHIYAMA

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 120
Author(s):  
Guangyu Zhao ◽  
Yihui Wei ◽  
Jiaqi Chen ◽  
Yuhong Dong ◽  
Lingyu Hou ◽  
...  

Purpose: This research was aimed to screen and identify multifunctional phosphorus-dissolving bacteria of a Chinese fir (Cunninghamia lanceolata) plantation and study its phosphorus-dissolving characteristics in order to provide strain resources and a theoretical basis for developing the appropriate bacterial fertilizer of a Chinese fir plantation. Methods: First, phosphorus-dissolving bacteria were isolated from the woodland soil of a Chinese fir plantation by Pikovskava inorganic phosphorus medium (PVK). Then, some growth-promoting indicators of primary screening strains were determined, including the capacity of phosphorus-solubilized, nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, production of indole-3-acetic acid (IAA), secretion of iron carrier and so on. Finally, the screening multifunctional phosphorus-dissolving bacteria were identified, which were combined with colony characteristics, physiological and biochemical tests and molecular biotechnology. Results: (1) Thirteen phosphorus-dissolving bacteria were isolated and screened in total, and P5 (195.61 mg·L−1) had the strongest capacity of phosphorus-solubilized. Five phosphorus-dissolving bacteria were provided with nitrogenase activity, and the highest activity of nitrogenase was P10 and P5 (71.90 C2H4 nmol·mL−1·h−1 and 71.00 C2H4 nmol·mL−1·h−1, respectively). Four strains were provided with ACC deaminase activity, and the highest activity of ACC deaminase was P5 and P9, (0.74 μmol·mg−1·h−1 and 0.54 μmol·mg−1·h−1, respectively). Most strains could secrete IAA, and three strains of bacteria had a strong secretory ability, which could secrete IAA with a concentration greater than 15 mg·mL−1, and P5 was 18.00, P2 was 17.30, P6 was 15.59 (mg·mL−1). P5 produced carriers of iron better than others, and the ratio of the diameter of the iron production carrier ring to the diameter of the colony was 1.80, respectively, which was significantly higher than other strains. Combining all kinds of factors, P5 multifunctional phosphorus-dissolving bacteria were screened for eventual further study. (2) Strain P5 was identified as Burkholderia ubonensis, based on the colony characteristics, physiological and biochemical tests, 16SrDNA sequence analysis and phylogenetic tree construction. Conclusion: P5 has a variety of high-efficiency growth-promoting capabilities, and the ability to produce IAA, ACC deaminase activity and siderophore performance are significantly higher than other strains, which had great potential in the development of microbial fertilizer.


2015 ◽  
Vol 3 (3) ◽  
pp. 552-560 ◽  
Author(s):  
Mohamed A.M. El-Awady ◽  
Mohamed M. Hassan ◽  
Yassin M. Al-Sodany

This study was designed to isolate and characterize endophytic and rhizospheric bacteria associated with the halophyte plant Sesuvium verrucosum, grown under extreme salinity soil in Jeddah, Saudi Arabia. The plant growth promotion activities of isolated bacterial were evaluated in vitro. A total of 19 salt tolerant endophytic and rhizospheric bacterial isolates were obtained and grouped into six according to genetic similarity based on RAPD data. These six isolates were identified by amplification and partial sequences of 16S rDNA as Enterobacter cancerogenus,Vibrio cholerae, Bacillus subtilis, Escherichia coli and two Enterobacter sp. Isolates were then grown until exponential growth phase to evaluate the atmospheric nitrogen fixation, phosphate solubilization, and production of phytohormones such as indole-3-acetic acid, as well as 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. While, All of the six strains were negative for ACC deaminaseactivity, two isolates showed Nitrogen fixation activity, three isolates produce the plant hormone (Indole acetic acid) and two isolates have the activity of solubiliztion of organic phosphate. Among the six isolates, the isolate (R3) from the soil around the roots is able to perform the three previous growth promoting possibilities together and it is ideal for use in promoting the growth of plants under the high salinity conditions. This isolate is candidate to prepare a friendly biofertelizer that can be used for the improvement of the crops performance under salinity conditions.Int J Appl Sci Biotechnol, Vol 3(3): 552-560


1985 ◽  
Vol 49 (7) ◽  
pp. 2181-2183 ◽  
Author(s):  
Shin''ichi KUROSAWA ◽  
Kazuharu KATOH ◽  
Hideki YOKOMICHI

2021 ◽  
Vol 11 (5) ◽  
pp. 2233
Author(s):  
Maria J. Ferreira ◽  
Angela Cunha ◽  
Sandro Figueiredo ◽  
Pedro Faustino ◽  
Carla Patinha ◽  
...  

Root−associated microbial communities play important roles in the process of adaptation of plant hosts to environment stressors, and in this perspective, the microbiome of halophytes represents a valuable model for understanding the contribution of microorganisms to plant tolerance to salt. Although considered as the most promising halophyte candidate to crop cultivation, Salicornia ramosissima is one of the least-studied species in terms of microbiome composition and the effect of sediment properties on the diversity of plant-growth promoting bacteria associated with the roots. In this work, we aimed at isolating and characterizing halotolerant bacteria associated with the rhizosphere and root tissues of S. ramosissima, envisaging their application in saline agriculture. Endophytic and rhizosphere bacteria were isolated from wild and crop cultivated plants, growing in different estuarine conditions. Isolates were identified based on 16S rRNA sequences and screened for plant-growth promotion traits. The subsets of isolates from different sampling sites were very different in terms of composition but consistent in terms of the plant-growth promoting traits represented. Bacillus was the most represented genus and expressed the wider range of extracellular enzymatic activities. Halotolerant strains of Salinicola, Pseudomonas, Oceanobacillus, Halomonas, Providencia, Bacillus, Psychrobacter and Brevibacterium also exhibited several plant-growth promotion traits (e.g., 3-indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, siderophores, phosphate solubilization). Considering the taxonomic diversity and the plant-growth promotion potential of the isolates, the collection represents a valuable resource that can be used to optimize the crop cultivation of Salicornia under different environmental conditions and for the attenuation of salt stress in non-halophytes, considering the global threat of arable soil salinization.


Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 888
Author(s):  
Giorgia Novello ◽  
Patrizia Cesaro ◽  
Elisa Bona ◽  
Nadia Massa ◽  
Fabio Gosetti ◽  
...  

The reduction of chemical inputs due to fertilizer and pesticide applications is a target shared both by farmers and consumers in order to minimize the side effects for human and environmental health. Among the possible strategies, the use of biostimulants has become increasingly important as demonstrated by the fast growth of their global market and by the increased rate of registration of new products. In this work, we assessed the effects of five bacterial strains (Pseudomonas fluorescens Pf4, P. putida S1Pf1, P. protegens Pf7, P. migulae 8R6, and Pseudomonas sp. 5Vm1K), which were chosen according to their previously reported plant growth promotion traits and their positive effects on fruit/seed nutrient contents, on a local onion cultivar and on zucchini. The possible variations induced by the inoculation with the bacterial strains on the onion nutritional components were also evaluated. Inoculation resulted in significant growth stimulation and improvement of the mineral concentration of the onion bulb, induced particularly by 5Vm1K and S1Pf1, and in different effects on the flowering of the zucchini plants according to the bacterial strain. The present study provides new information regarding the activity of the five plant growth-promoting bacteria (PGPB) strains on onion and zucchini, two plant species rarely considered by the scientific literature despite their economic relevance.


Sign in / Sign up

Export Citation Format

Share Document