scholarly journals ALLELOPATHIC POTENTIAL OF AQUEOUS EXTRACT OF LEAF AND ROOT SESAME ON SICKLEPOD AND BRACHIARIA SEEDS

2021 ◽  
Vol 15 (4) ◽  
pp. 523-537
Author(s):  
Gustavo Ferreira da Silva ◽  
Nilbe Carla Mapeli ◽  
Cassiano Cremon ◽  
Larissa Chamma ◽  
Bruno Cesar Ottoboni Luperini ◽  
...  

Sicklepod is an important weed in Brazil pastures, but control measures are not yet effective. Thus, allelopathy can be an alternative, due to its ecological importance and for being able to provide new structures sources for agrochemicals production. This research aimed to verify the allelopathic potential of sesame (Sesamum indicum L.) on germination and seedling development of sicklepod (Senna occidentalis L.) and brachiaria (Brachiaria brizantha). The treatments were root and leaf extract of sesame, and control (distilled water).  Germination percentage, speed of germination, hypocotyl and radicle length were evaluated. Speed of germination, germination percentage and radicle length had no interference from the aqueous extracts. However, in brachiaria these traits had lower values than sicklepod. Hypocotyl length was not influenced by the extracts, however, the leaf extract showed lower growth of this feature. Allelopathy did not affect germination and speed of germination in both species, but interfered in brachiaria development.

2022 ◽  
Vol 11 (1) ◽  
pp. e6911124863
Author(s):  
Gabrielli Monzani de Lima ◽  
José Donizetti de Lima ◽  
Vanderlei Aparecido de Lima ◽  
Michelangelo Muzell Trezzi ◽  
Beatriz Helena Lameiro de Noronha Sales Maia ◽  
...  

Salicylic acid has one of its characteristics the allelopathic potential. The present paper, is a research quantitative in nature aimed to assess the allelopathic potential of salicylic acid to identify the best concentration range for other pure substances. The bioassays were performed in a BOD incubator, seeking to assess the seedling growth by measuring the radicle and hypocotyl length. Each bioassay occurred for 12 days. The concentrations of salicylic acid used in the bioassays were: 1000, 750, 500, 250, 125, and 62.5 ppm and control. The obtained data were submitted to the tests: Kolmogorov-Smirnov normality, the two-way ANOVA with repetition, and Tukey. Based on the results obtained, it was possible to observe that several concentrations demonstrated significant differences, i.e., there is an allelopathic activity in both species (Euphorbia heterophylla and Bidens pilosa). The highlights were for the concentrations of 750 and 1000 ppm for E. heterophylla and 500, 750 and 1000 ppm for B. pilosa. However, there was no significant difference between these concentration groups. The radicle’s length was the part most negatively affected. These results can be used to identify better concentrations for other pure substances, which are usually obtained in small quantities, being useful in the formulation of a product with characteristics of bio-herbicides.


Weed Science ◽  
1982 ◽  
Vol 30 (4) ◽  
pp. 385-388 ◽  
Author(s):  
Gary L. Cramer ◽  
Orvin C. Burnside

Infestations of common milkweed (Asclepias syriacaL.), in descending order of incidence in Nebraska, occurred on areas occupied by soybean [Glycine max(L.) Merr.], oats (Avena sativaL.), sorghum [Sorghum bicolor(L.) Moench.], railroad rights-of-way, fallow land, roadsides, corn (Zea maysL.), winter wheat (Triticum aestivumL.), pasture, and alfalfa (Medicago sativaL.). Average crop yield reductions, within common milkweed communities of 11100 to 45 200 plants/ha, ranged from 2 to 10% for corn, 4 to 29% for sorghum, and 12 to 19% for soybeans. Reductions in crop yields tended to increase with increasing common milkweed populations. Germination percentage of common milkweed and sorghum were not significantly affected by growing medium conductivities below 7 and 13 mmho/cm2, respectively. Growth media at pH 2 significantly reduced germination percentage, hypocotyl length, and radicle length of both common milkweed and sorghum as compared with pH 4 to 10. Undiluted aqueous extracts of common milkweed shoot and root material significantly reduced germination percentage, hypocotyl length, and radicle length of sorghum.


Author(s):  
Y. Arockia Suganthi ◽  
Chitra K. ◽  
J. Magelin Mary

Dengue fever is a painful mosquito-borne infection caused by different types of virus in various localities of the world. There is no particular medicine or vaccine to treat person suffering from dengue fever. Dengue viruses are transmitted by the bite of female Aedes (Ae) mosquitoes. Dengue fever viruses are mainly transmitted by Aedes which can be active in tropical or subtropical climates. Aedes Aegypti is the key step to avoid infection transmission to save millions of people in all over the world. This paper provides a standard guideline in the planning of dengue prevention and control measures. At the same time gives the priorities including clinical management and hospitalized dengue patients have to address essentially.


1986 ◽  
Vol 18 (9) ◽  
pp. 197-205
Author(s):  
Lj Jeftié ◽  
L. J. Saliba

Increasing concern over the deterioration of the Mediterranean sea as a result of increasing pollution by untreated sewage and industrial wastes, agricultural pesticides and fertilizers and oil discharges, led to a series of meetings between 1970 and 1974, and finally to the UNEP-sponsored Mediterranean Action Plan, adopted by governments of the region in 1975 and ongoing since that time. The legal component of the Plan includes a framework Convention and four protocols; the environmental assessment component (the MED POL programme) consists of national pollution monitoring programmes, and research projects conducted by Mediterranean institutions; the environmental management component consists of the Blue Plan (a prospective study combining socio-economic development with environmental preservation) and the Priority Actions Programme (a series of sub-region sectoral projects in defined areas). The Plan has been financed by Mediterranean States since 1979, and is managed by UNEP with the cooperation of other competent UN Agencies. During the last ten years, activities undertaken have improved knowledge of the state of pollution of the Mediterranean sea, and facilitated joint regional action in the form of preventive and control measures.


2020 ◽  
Author(s):  
Qiangsheng Huang

BACKGROUND As of the end of February 2020, 2019-nCoV is currently well controlled in China. However, the virus is now spreading globally. OBJECTIVE This study aimed to evaluate the effectiveness of outbreak prevention and control measures in a region. METHODS A model is built for find the best fit for two sets of data (the number of daily new diagnosed, and the risk value of incoming immigration population). The parameters (offset and time window) in the model can be used as the evaluation of effectiveness of outbreak prevention and control. RESULTS Through study, it is found that the parameter offset and time window in the model can accurately reflect the prevention effectiveness. Some related data and public news confirm this result. And this method has advantages over the method using R0 in two aspects. CONCLUSIONS If the epidemic situation is well controlled, the virus is not terrible. Now the daily new diagnosed patients in most regions of China is quickly reduced to zero or close to zero. Chinese can do a good job in the face of huge epidemic pressure. Therefore, if other countries can do well in prevention and control, the epidemic in those places can also pass quickly.


2020 ◽  
Author(s):  
Yushi Mo ◽  
Yan Luo ◽  
Hong Li ◽  
Dewei Xiao ◽  
Shuqing Liu ◽  
...  

BACKGROUND In face of the sudden epidemic of COVID-19, strict prevention and control measures had been urgently carried out all over China. Because of the long-term home quarantine, all kinds of people were affected by it. OBJECTIVE In order to understand the mental health of children during the pandemic of COVID-19, this study investigated the prevalence and characteristics of emotional and behavioral problems of children aged 1-11 in Guizhou. METHODS Based on the online survey platform, the survey link was pushed through Wechat in April 2020. Electronic questionnaires were used to investigate children's demographic characteristics, emotional or behavioral problems. RESULTS A total of 3505 valid questionnaires were received from 9 prefectures and cities in Guizhou Province. 39.67% of the children in the 1-2-year-old group had emotional problems. 17.63% of the children agd 3-5 years had behavioral or emotional problems. And 23.57% of the children agd 6-11 years havd behavioral problems. CONCLUSIONS During the home quarantine period of prevention and control of COVID-19, even young children were adversely affected. The prevalence of emotional and behavioral problems in children was high, which was mainly manifested as anxiety, difficulty in concentration and sleep problems.


Author(s):  
Ann M. Krake

This chapter covers extremes of temperature conditions, physiological effects, and prevention. All deaths caused by exposure to hot and cold temperature extremes are preventable when proper measures are taken. Described in this chapter are the effects of extreme heat and extreme cold on the health of members of the public, particularly older people and young people, and workers employed in various workplace settings. The differences between heat stress and heat strain are also discussed, as are various regulations governing exposure to temperature extremes. The nature and magnitude of heat- and cold-related conditions and symptoms are described in detail. Final sections of the chapter address various assessment and evaluation tools as well as prevention and control measures. In addition, an appendix describes the hazards related to hyperbaric and hypobaric environments and adverse health effects.


Weed Science ◽  
1987 ◽  
Vol 35 (5) ◽  
pp. 695-699 ◽  
Author(s):  
Steven M. Brown ◽  
James M. Chandler ◽  
John E. Morrison

A field experiment was conducted to evaluate weed control systems in a conservation tillage rotation of grain sorghum [Sorghum bicolor(L.) Moench.] – cotton (Gossypium hirsutumL.) – wheat (Triticum aestivumL.). Herbicide systems included fall and spring/summer inputs of high and low intensity. Tillage regimes were no-till (NT) and reduced-till (RT) systems; the latter included fall primary tillage followed by spring stale seedbed planting. Both tillage systems utilized controlled traffic lanes and wide, raised beds. Effective johnsongrass [Sorghum halepense(L.) Pers. # SORHA] control required intense herbicide inputs at one or both application periods, i.e., in the fall and/or spring/summer. Grain sorghum and cotton yields for the most intense weed control system, which included high inputs in both the fall and spring/summer, were not superior to systems that included high inputs in only one of the two application periods. Seedling johnsongrass emergence occurred before spring planting in RT (but not in NT) in 2 of 3 yr, and control measures were ineffective. After 3 yr, the predominant weeds were johnsongrass and browntop panicum (Panicum fasciculatumSw. # PANFA).


Sign in / Sign up

Export Citation Format

Share Document