scholarly journals Filtrates from cultures of endophytic fungi isolated from leaves of Copaifera oblongifolia (Fabaceae) affect germination and seedling development differently

2023 ◽  
Vol 83 ◽  
Author(s):  
P. S. Silva ◽  
V. A. Royo ◽  
H. M. Valerio ◽  
E. G. Fernandes ◽  
M. V. Queiroz ◽  
...  

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.

2015 ◽  
Vol 35 (21) ◽  
Author(s):  
李绍锋 LI Shaofeng ◽  
王国红 WANG Guohong ◽  
饶佳媚 RAO Jiamei ◽  
杨民和 YANG Minhe

2021 ◽  
Author(s):  
Cornelius Kibet Kipyegen ◽  
Charles I. Muleke ◽  
Elick O. Otachi

Abstract Fasciolosis is a neglected trematode infection of public health and veterinary importance caused by Fasciola gigantica and Fasciola hepatica. Molecular analysis using the internal transcribed spacers’ ITS-1 and ITS-2 of nuclear ribosomal DNA is useful in distinguishing Fasciola species. This study aimed to characterize liver flukes from sheep, goats and cattle using these genetic markers. Fifty nine adult Fasciola specimens were collected from livers of naturally infected sheep, goats and cattle at selected abattoirs in Kisumu, Baringo and Narok Counties. Sequence comparison of ITS-1 and ITS-2 sequences of Fasciola isolates from this study and sequences in Genbank was carried out. A maximum likelihood tree was constructed for phylogenetic analysis. Analysis of ITS-1 and ITS-2 rDNA sequences revealed that F. hepatica and F. gigantica caused infection in both cattle and sheep and in goats only F. gigantica caused infection. The sequenced PCR amplicons showed a close relationship between Fasciola species in this study with Fasciola isolates from other regions in the world. Phylogenetic analysis showed that sequences of F. hepatica are similar to the sequence from Spain, China and Tunisia obtained from GenBank. The sequences of F. gigantica in this study have similarity to the sequence from Iran and Burkina Faso. Data from this study provides information that serves as basis for further studies on the distribution of F. gigantica and F. hepatica in other localities in Kenya, and is also important in designing epidemiological and control programmes for zoonotic fascioliasis.


2012 ◽  
Vol 88 (1) ◽  
pp. 74-81 ◽  
Author(s):  
G.H. Zhao ◽  
B. Hu ◽  
J.K. Song ◽  
Y.Q. Jia ◽  
H.M. Li ◽  
...  

AbstractIn the present study, the internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of Oesophagostomum asperum and O. columbianum were amplified and sequenced. The ITS-1, 5.8S and ITS-2 rDNA sequences of O. asperum were 374 bp, 153 bp and 259 bp in length, respectively, and the corresponding sequences of O. columbianum were 259, 153 and 218 bp in length, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA between the two Oesophagostomum species were 9.5–10.2% and 12.7–13.9%, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA among members of the genus Oesophagostomum were 2.5–11.6% and 6.8–22.3%, respectively. Based on genetic markers in the ITS rDNA, an effective polymerase chain reaction (PCR) approach was developed to differentiate O. columbianum from O. asperum with a sensitivity of 0.2 ng/μl DNA. Since accurate characterization of parasites at different taxonomic levels is essential for population genetic studies and control of parasitosis, the present findings have important implications for studying epidemiology, taxonomy and population biology, as well as for the control of oesophagostomiasis.


2002 ◽  
Vol 16 (2) ◽  
pp. 109-124 ◽  
Author(s):  
William E. Shafer ◽  
D. Jordan Lowe ◽  
Timothy J. Fogarty

The current trend toward corporate acquisitions of CPA firms poses potential threats to the autonomy and ethical standards of public accounting professionals. This recent consolidation movement suggests that for the first time a significant number of public accounting professionals are subject to the supervision and control of nonprofessionals. In addition to acknowledging the potential threats to auditor independence and objectivity, this paper suggests that these new organizational arrangements for the provision of public accounting services have other negative effects on professionalism and ethics such as desensitizing CPAs to traditional professional values, and subverting professional institutions to the goals of corporate employers. This paper develops a framework that identifies several specific research questions related to the effects of corporate ownership on professionalism and ethics in public accounting.


2021 ◽  
Vol 9 (6) ◽  
pp. 1184
Author(s):  
Nomfusi Ntsobi ◽  
Morris Fanadzo ◽  
Marilize Le Roes-Hill ◽  
Felix Nchu

Globally, fungal inocula are being explored as agents for the optimization of composting processes. This research primarily evaluates the effects of inoculating organic vegetable heaps with the entomopathogenic fungus Clonostachys rosea f. catenula (Hypocreales) on the biophysicochemical properties of the end-product of composting. Six heaps of fresh cabbage (Brassica oleracea var. capitata) waste were inoculated with C. rosea f. catenula conidia and another six were not exposed to the fungus. The composted materials from the fungus- and control-treated heaps were subsequently used as a medium to cultivate tomatoes (Solanum lycopersicum). The biophysicochemical characteristics of the composted materials were also assessed after composting. In addition, the protective effect of the fungal inoculum against red spider mite (Tetranychus urticae) infestations in the tomatoes was evaluated through the determination of conidial colonization of the plant tissue and the number of plants infested by the insect. Furthermore, phytotoxicity tests were carried out post experiment. There were few significant variations (p < 0.05) in heap temperature or moisture level between treatments based on the weekly data. We found no significant differences in the levels of compost macronutrient and micronutrient constituents. Remarkably, the composted materials, when incorporated into a growth medium from fungus-treated heaps, induced a 100% endophytic tissue colonization in cultivated tomato plants. While fewer red spider mite infestations were observed in tomato plants grown in composted materials from fungus-treated heaps, the difference was not significant (χ2 = 0.96 and p = 0.32). The fungal treatment yielded composted materials that significantly (p < 0.05) enhanced tomato seed germination, and based on the phytotoxicity test, the composted samples from the heaps exposed to the C. rosea f. catenula inoculum were not toxic to tomato seeds and seedlings. In conclusion, this study showed that C. rosea f. catenula improved the quality of composted materials in terms of fungal endophytism and seed germination.


Author(s):  
Mauro Pontani ◽  
Fabio Celani

AbstractAccurate orbit injection represents a crucial issue in several mission scenarios, e.g., for spacecraft orbiting the Earth or for payload release from the upper stage of an ascent vehicle. This work considers a new guidance and control architecture based on the combined use of (i) the variable-time-domain neighboring optimal guidance technique (VTD-NOG), and (ii) the constrained proportional-derivative (CPD) algorithm for attitude control. More specifically, VTD-NOG & CPD is applied to two distinct injection maneuvers: (a) Hohmann-like finite-thrust transfer from a low Earth orbit to a geostationary orbit, and (b) orbit injection of the upper stage of a launch vehicle. Nonnominal flight conditions are modeled by assuming errors on the initial position, velocity, attitude, and attitude rate, as well as actuation deviations. Extensive Monte Carlo campaigns prove effectiveness and accuracy of the guidance and control methodology at hand, in the presence of realistic deviations from nominal flight conditions.


2021 ◽  
Vol 22 (9) ◽  
pp. 4738
Author(s):  
Hye-Yeon Seok ◽  
Hyungjoon Bae ◽  
Taehyoung Kim ◽  
Syed Muhammad Muntazir Mehdi ◽  
Linh Vu Nguyen ◽  
...  

Despite increasing reports on the function of CCCH zinc finger proteins in plant development and stress response, the functions and molecular aspects of many non-tandem CCCH zinc finger (non-TZF) proteins remain uncharacterized. AtC3H59/ZFWD3 is an Arabidopsis non-TZF protein and belongs to the ZFWD subfamily harboring a CCCH zinc finger motif and a WD40 domain. In this study, we characterized the biological and molecular functions of AtC3H59, which is subcellularly localized in the nucleus. The seeds of AtC3H59-overexpressing transgenic plants (OXs) germinated faster than those of wild type (WT), whereas atc3h59 mutant seeds germinated slower than WT seeds. AtC3H59 OX seedlings were larger and heavier than WT seedlings, whereas atc3h59 mutant seedlings were smaller and lighter than WT seedlings. Moreover, AtC3H59 OX seedlings had longer primary root length than WT seedlings, whereas atc3h59 mutant seedlings had shorter primary root length than WT seedlings, owing to altered cell division activity in the root meristem. During seed development, AtC3H59 OXs formed larger and heavier seeds than WT. Using yeast two-hybrid screening, we isolated Desi1, a PPPDE family protein, as an interacting partner of AtC3H59. AtC3H59 and Desi1 interacted via their WD40 domain and C-terminal region, respectively, in the nucleus. Taken together, our results indicate that AtC3H59 has pleiotropic effects on seed germination, seedling development, and seed development, and interacts with Desi1 in the nucleus via its entire WD40 domain. To our knowledge, this is the first report to describe the biological functions of the ZFWD protein and Desi1 in Arabidopsis.


Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 419
Author(s):  
Siaka Dembélé ◽  
Robert B. Zougmoré ◽  
Adama Coulibaly ◽  
John P. A. Lamers ◽  
Jonathan P. Tetteh

Agriculture in Mali, a country in Sahelian West Africa, strongly depends on rainfall and concurrently has a low adaptive capacity, making it consequently one of the most vulnerable regions to climate change worldwide. Since early-season drought limits crop germination, and hence growth, ultimately yield during rain-fed depending on production is commonly experienced nowadays in Mali. Germination and establishment of key crops such as the staple sorghum could be improved by seed priming. The effects of hydro-priming with different water sources (e.g., distilled, tap, rain, river, well water) were evaluated respectively for three priming time durations in tepid e.g., at 25 °C (4, 8, and 12 h) and by hot water at 70 °C (in contrast to 10, 20, and 30 min.) in 2014 and 2015. Seed germination and seedling development of nine sorghum genotypes were monitored. Compared to non-primed seed treatments, hydro-priming significantly [p = 0.01] improved final germination percentage, germination rate index, total seedling length, root length, root vigor index, shoot length, and seedling dry weight. The priming with water from wells and rivers resulted in significant higher seed germination (85%) and seedling development, compared to the three other sources of water. Seed germination rate, uniformity, and speed were enhanced by hydro-priming also. It is argued that hydro-priming is a safe and simple method that effectively improve seed germination and seedling development of sorghum. If used in crop fields, the above most promising genotypes may contribute to managing early season drought and avoid failure of seed germination and crop failure in high climate variability contexts.


2011 ◽  
Vol 98 (10) ◽  
pp. 1613-1622 ◽  
Author(s):  
Clesnan Mendes-Rodrigues ◽  
Marli A. Ranal ◽  
Paulo E. Oliveira

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