• Advances in environmental research
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• v.4 no.1
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• pp.1-15
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• 2015

A pot experiment was conducted to assess the effects of red pepper (Capsicum annuum) and coriander (Coriandrum sativum) on seedling growth of wheat (Triticum aestivum). The aqueous extracts treatment of red pepper and coriander showed a significant (p < 0.05) reduction in root, shoot and seedling length, number of leaves and seedling dry weight of wheat (T. aestivum) as compared to control. The inhibitory different effect on growth of wheat (T. aestivum) was directly proportional to the increasing concentration (1, 2, 3, 4 and 5%) of aqueous extracts of red pepper and coriander as compared to control treatment (0%). The root, shoot, seedling length and number of leaves of T. aestivum significantly p < 0.05 decreased at 5% concentration of red pepper as compared to control. The root, shoot and seedling growth of T. aestivum was also significantly reduced at 1, 2, 3, 4 and 5% concentration of coriander as compared to control. The root, shoot and leaves dry weight of T. aestivum at 5% coriander extract treatment concentration decreased as compared to control. The tolerance in seedlings of T. aestivum to red pepper and coriander extract treatment was dose dependent as compared to control. The seedlings of T. aestivum showed low percentage of tolerance to pepper extract treatment than coriander extract treatment.

• Mycobiology
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• v.38 no.2
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• pp.113-117
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• 2010

Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 + A. tenuis), T6 (T. harzianum IMI-392434 + A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 + A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.

• Mycobiology
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• v.38 no.2
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• pp.97-101
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• 2010

Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica.

• Korean Journal of Microbiology
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• v.6 no.4
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• pp.107-112
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• 1968

Examining the microbial populations in the Han River estuary, we conducted this experiment at six sites of the estuarine area, Chollyu-ri, Cholsan-ri, Wolgon-ri, Chogi-ri, Inhwa-ri, and Oepo-ri for 5 months since May 1967. From the results obtained it could be summarized as follows. 1) The salinity of the estuarine water increased in order of the distances from the base point of the Old Han River Bridge to every site of the estuary, and pH of the water, which were between 7. 3 and 8. 1, showing little difference each other in both the sites and dates of experiment. 2) The populations of the general bacteria and coliform group bacteria were highest at the site of Chollyu-ri, and it decreased with the downstreaming of the river water toward Oepo-ri site. As for fungi which have comparatively high tolerance to the salinity, its population was shown hi hest at Chogi-ri. 3) The relationship between the salinity and the number of the general bacteria have indicated that the incresed salinity reduced the growth rates of the bacteria. By this it can be assumed that the fresh-water bacteria decreased due to the sea water as well as its dilution effects. 4) The high pollution of the esturarine water was caused by the increases of inhabitants and water thrown by industries in Seoul and Kyung-In Industrial District as well as the excrements fertilized to the farms.

• Korean Journal of Microbiology
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• v.15 no.1
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• pp.9-19
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• 1977

Xylone isomerase (D-xylose ketol-isomerase, EC 5,3,1,5) have been demonstrated in the cell-free extracts of Stroptomuces canus and Streptomuces malachiticus grown in the presence of xylose. Xylose, glucose and ribose served as substrates for the enzymes of the two strains with respective $K_m$ values of 22, 130, 290 mM (S. canus) and 7,83,637 mM(S.malachiticus), and $V_max$ values of 1,000, 0.087, $\0.0222{\mu}moles/min/mg$ protein (S. canus) and 0.312, 0.083, 0.500.$\mu$moles/min/mg protein (S. malachiticus). L-Rhammose was also isomerized by the crude enzyme solutions of the two strains. The maximal activities of the two xylose-isomerases were observed at pH 7.5 and $75^{\circ}C$. The xylose isomerase activities of the two strains were activated two-three times by $Mg^{++}\;and\;Co^{++}$ as that of control, partially activated by $Ba^{++}$ and inhibited by $Ni^{++},\;Ca^{++}\;and\;Zn^{++}\$. Particulary, the addtion of $Mn^{++}$ stimulated xylose-isomerizing activities, but inhibited glucose-isomerizing activities in both strains. However, $Cu^{++}$ inhibited xylose-isomerizing activities, while stimulated glucose-isomerizing activities of the enzymes.

• Mycobiology
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• v.32 no.4
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• pp.170-172
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• 2004

The efficiency of acid, enzyme and microbial pretreatment of rice bran was compared based on the content of cellulose, hemicellulose, reducing sugars and xylose in the substrate. An isolate of Aspergillus niger or a strain of Trichoderma viride(MTCC 800) was employed for microbial pretreatment of rice bran in solid state. Acid pretreatment resulted in the highest amount of reducing sugars followed by enzyme and microbial pretreatment. A. niger showed a higher rate of hydrolysis than T. viride. The rice bran hydrolysate obtained from the different methods was subsequently fermented to ethanol either by Zymomonas mobilis(NCIM 806) or by Pichia stipitis(NCIM 3497). P. stipitis fermentation resulted in higher ethanol(37% higher) and biomass production($76{\sim}83%$ higher) than those of Z. mobilis. Maximum ethanol production resulted at 12h in Zymomonas fermentation, while in Pichia fermentation, it was observed at 60h. Microbial pretreatment of rice bran by A. niger followed by fermentation employing P. stipitis was more efficient but slower than the other microbial pretreatment and fermentation.

• Mycobiology
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• v.37 no.4
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• pp.277-285
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• 2009

In this study, dual culture, poison agar, and direct methods were used to assess the ability of Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433, and T. harzianum IMI-392434 to control Ceratocystis paradoxa, which causes the pineapple disease of sugarcane. The highest percentage inhibition of radial growth (PIRG) values were observed with T. harzianum IMI-392432 using two dual culture methods, 63.80% in Method I and 80.82% in Method II. The minimum colony overgrowth time was observed with T. harzianum IMI-392432 and the maximum was observed with T. pseudokoningii IMI-392431. Different concentrations of different day-old metabolites of Trichoderma isolates were tested against mycelial growth of C. paradoxa. The highest PIRG (84.685%) exhibited at 80% concentration of 30-day-old metabolites of T. harzianum IMI-392432 using the modified bilayer poison agar method. In the direct assay method the maximum mycelial growth weight (PIGW) was observed at the same concentration and the same day-old metabolites of T. harzianum IMI-392432. This study showed that Trichoderma isolates have a good antagonistic effect on C. paradoxa mycelial growth and T. harzianum IMI-392432 has the most potential to control the pineapple disease pathogen.

• The Plant Pathology Journal
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• v.35 no.2
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• pp.137-148
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• 2019

In search of an effective biological control agent against the tomato pathogen Fusarium oxysporum f. sp. lycopersici, rhizospheric soil samples were collected from eight agro-ecological zones of Bangladesh. Among the bacteria isolated from soil, 24 isolates were randomly selected and evaluated for their antagonistic activity against F. oxysporum f. sp. lycopersici. The two promising antagonistic isolates were identified as Brevundimonas olei and Bacillus methylotrophicus based on morphological, biochemical and molecular characteristics. These two isolates were evaluated for their biocontrol activity and growth promotion of two tomato cultivars (cv. Pusa Rubi and Ratan) for two consecutive years. Treatment of Pusa Rubi and Ratan seeds with B. olei prior to inoculation of pathogen caused 44.99% and 41.91% disease inhibition respectively compared to the untreated but pathogen-inoculated control plants. However, treatment of Pusa Rubi and Ratan seeds with B. methylotrophicus caused 24.99% and 39.20% disease inhibition respectively. Furthermore, both the isolates enhanced the growth of tomato plants. The study revealed that these indigenous bacterial isolates can be used as an effective biocontrol agent against Fusarium wilt of tomato.

• ALGAE
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• v.34 no.3
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• pp.187-198
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• 2019

The exploration of seaweed diversity in poorly studied habitats has often led to the discovery of new species. Sand-covered rocks are an example, as they received less attention than sand-free rocky intertidal habitats during seaweed diversity surveys in Brazil. In sand-covered rocks from Espirito Santo and Rio de Janeiro we found an alga whose morphology was unique among rhodomelacean species previously reported in Brazil. With the aim to clarify the taxonomic identity of this species we studied its morphology, as well as its phylogenetic relationships. Molecular analyses resolved this species in the genus Alsidium (tribe Alsidieae) and differed from sequenced congeners with divergences ${\geq}2.5$ and 4.2% in the rbcL and cox1 genes, respectively. Morphological characters were in agreement with the genus Alsidium, and differed from other species currently recognized in the genus. The species consisted of a basal crust and scarcely branched erect axes with seven pericentral cells covered by a continuous layer of cortical cells. Reproductive structures were formed on clusters of short determinate branches. Therefore, the new species A. oliveiranum is proposed based on morphological and molecular evidence. Our findings contribute to better understand the diversity of the tribe Alsidieae, which is particularly diverse in the Americas.

• Mycobiology
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• v.48 no.6
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• pp.464-475
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• 2020

Acervus (Pyronemataceae, Pezizales) is a saprobic genus in Pezizomycetes, characterized by colored apothecia, subcylindrical to cylindrical asci and guttulate ascospores. We collected four Acervus samples from China and Thailand. Descriptions and illustrations are introduced for all fresh samples. One new record of A. globulosus from Thailand, one new species, A. rufus, two known species, A. epispartius and A. stipitatus from China are reported. Phylogenetic analysis based on five genes, the large subunit rRNA (LSU), the translation elongation factor-1 alpha (tef1-α), the second largest subunit of RNA polymerase II (rpb2), the largest subunit of RNA polymerase II (rpb1), and the small subunit rRNA (SSU), revealed the distinct position of the new species. The new species is set apart by its red apothecia. A key to Acervus species is also given.