Controlling Citrus Huanglongbing: Green Sustainable Development Route Is the Future

Huanglongbing (HLB) is the most severe bacterial disease of citrus crops caused by Candidatus Liberibacter spp. It causes a reduction in fruit yield, poor fruit quality, and even plants death. Due to the lack of effective medicine, HLB is also called citrus “AIDS.” Currently, it is essential for the prevention and control of HLB to use antibiotics and pesticides while reducing the spread of HLB by cultivating pathogen-free seedlings, removing disease trees, and killing Asian citrus psyllid (ACP). New compounds [e.g., antimicrobial peptides (AMPs) and nanoemulsions] with higher effectiveness and less toxicity were also found and they have made significant achievements. However, further evaluation is required before these new antimicrobial agents can be used commercially. In this review, we mainly introduced the current strategies from the aspects of physical, chemical, and biological and discussed their environmental impacts. We also proposed a green and ecological strategy for controlling HLB basing on the existing methods and previous research results.

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Recent Advances in Surface Nanoengineering for Biofilm Prevention and Control. Part II: Active, Combined Active and Passive, and Smart Bacteria-Responsive Antibiofilm Nanocoatings

Nanomaterials ◽

10.3390/nano10081527 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1527 ◽

Cited By ~ 3

Author(s):

Paul Cătălin Balaure ◽

Alexandru Mihai Grumezescu

Keyword(s):

Antimicrobial Agent ◽

Prevention And Control ◽

Extracellular Polymeric Substances ◽

Molecular Mechanisms ◽

Antimicrobial Agents ◽

Selective Toxicity ◽

Bacterial Killing ◽

Chemical Structures ◽

And Control ◽

Biofilm Prevention

The second part of our review describing new achievements in the field of biofilm prevention and control, begins with a discussion of the active antibiofilm nanocoatings. We present the antibiofilm strategies based on antimicrobial agents that kill pathogens, inhibit their growth, or disrupt the molecular mechanisms of biofilm-associated increase in resistance and tolerance. These agents of various chemical structures act through a plethora of mechanisms targeting vital bacterial metabolic pathways or cellular structures like cell walls and cell membranes or interfering with the processes that underlie different stages of the biofilm life cycle. We illustrate the latter action mechanisms through inhibitors of the quorum sensing signaling pathway, inhibitors of cyclic-di-GMP signaling system, inhibitors of (p)ppGpp regulated stringent response, and disruptors of the biofilm extracellular polymeric substances matrix (EPS). Both main types of active antibiofilm surfaces, namely non-leaching or contact killing systems, which rely on the covalent immobilization of the antimicrobial agent on the surface of the coatings and drug-releasing systems in which the antimicrobial agent is physically entrapped in the bulk of the coatings, are presented, highlighting the advantages of each coating type in terms of antibacterial efficacy, biocompatibility, selective toxicity, as well as drawbacks and limitations. Developments regarding combined strategies that join in a unique platform, both passive and active elements are not omitted. In such platforms with dual functionality, passive and active strategies can be applied either simultaneously or sequentially. We especially emphasize those systems that can be reversely and repeatedly switched between the non-fouling status and the bacterial killing status, thereby allowing several bacteria-killing/surface regeneration cycles to be performed without significant loss of the initial bactericidal activity. Eventually, smart antibiofilm coatings that release their antimicrobial payload on demand, being activated by various triggers such as changes in local pH, temperature, or enzymatic triggers, are presented. Special emphasis is given to the most recent trend in the field of anti-infective surfaces, specifically smart self-defensive surfaces for which activation and switch to the bactericidal status are triggered by the pathogens themselves.

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Haemorrhagic septicaemia, its significance, prevention and control in Asia

Veterinární Medicína ◽

10.17221/5830-vetmed ◽

2012 ◽

Vol 47 (No. 8) ◽

pp. 234-240 ◽

Cited By ~ 33

Author(s):

A. Benkirane ◽

Alwis MCL De

Keyword(s):

Prevention And Control ◽

Animal Health ◽

National Level ◽

Sub Saharan Africa ◽

Economic Losses ◽

Bacterial Disease ◽

High Coverage ◽

Haemorrhagic Septicaemia ◽

Sub Saharan ◽

And Control

Haemorrhagic septicaemia (HS) is an endemic disease in most countries of Asia and sub-Saharan Africa. Within the Asian Region, countries can be classified into three categories, on the basis of incidence and distribution of the disease; these are respectively countries where the disease is endemic or sporadic, clinically suspected but not confirmed, or free. Economic losses due to HS are not only confined to losses to the animal industry, but also rice production on account of its high prevalence among draught animals used in rice fields. Only a few attempts have been made to estimate economic losses, the methodologies used in different countries have varied, and many are not based on active surveillance, and a consideration of all components of direct and indirect losses. Most Asian countries rank HS as the most important contagious disease or the most important bacterial disease in cattle and buffaloes. Resource allocation for prevention and control of HS nationally or internationally will evidently depend on a correct estimate of its economic impact. The key factors in prevention and control would be timely and correct reporting, accurate and rapid diagnosis, strategic use of vaccines with the attainment of a high coverage where necessary with a high quality vaccine. National level activities geared towards attainment of these objectives may be with advantage supported and strengthened by international organisations involved in animal health. The present paper attempts to review aspects related to the epidemiology, control and containment of HS in Asia and, proposes some key issues on which a regional programme for HS control in this continent should be centred.

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