Engineering Cold Stress Tolerance in Crop Plants

Plants respond with changes in their pattern of gene expression and protein products when exposed to low temperatures. Thus ability to adapt has an impact on the distribution and survival of the plant, and on crop yields. Many species of tropical or subtropical origin are injured or killed by non-freezing low temperatures, and exhibit various symptoms of chilling injury such as chlorosis, necrosis, or growth retardation. In contrast, chilling tolerant species are able to grow at such cold temperatures. Conventional breeding methods have met with limited success in improving the cold tolerance of important crop plants involving inter-specific or inter-generic hybridization. Recent studies involving full genome profiling/ sequencing, mutational and transgenic plant analyses, have provided a deep insight of the complex transcriptional mechanism that operates under cold stress. The alterations in expression of genes in response to cold temperatures are followed by increases in the levels of hundreds of metabolites, some of which are known to have protective effects against the damaging effects of cold stress. Various low temperature inducible genes have been isolated from plants. Most appear to be involved in tolerance to cold stress and the expression of some of them is regulated by C-repeat binding factor/ dehydration-responsive element binding (CBF/DREB1) transcription factors. Numerous physiological and molecular changes occur during cold acclimation which reveals that the cold resistance is more complex than perceived and involves more than one pathway. The findings summarized in this review have shown potential practical applications for breeding cold tolerance in crop and horticultural plants suitable to temperate geographical locations

Improving zinc and iron biofortification in wheat through genomics approaches

Globally, about 20% of calories (energy) come from wheat. In some countries, it is more than 70%. More than 2 billion people are at risk for zinc deficiency and even more, people are at risk of iron deficiency, nearly a quarter of all children underage group of 5 are physically and cognitively stunted, and lack of dietary zinc is a major contributing factor. Biofortified wheat with elevated levels of zinc and iron has several potential advantages as a delivery vehicle for micronutrients in the diets of resource-poor consumers who depend on cereal-based diets. The conventional breeding strategies have been successful in the introduction of novel alleles for grain Zn and Fe that led to the release of competitive Zn enriched wheat varieties in South Asia. The major challenge over the next few decades will be to maintain the rates of genetic gains for grain yield along with increased grain Zn/Fe concentration to meet the food and nutritional security challenges. Therefore, to remain competitive, the performance of Zn-enhanced lines/varieties must be equal or superior to that of current non-biofortified elite lines/varieties. Since both yield and Zn content are invisible and quantitatively inherited traits except few intermediate effect QTL regions identified for grain Zn, increased breeding efforts and new approaches are required to combine them at high frequency, ensuring that Zn levels are steadily increased to the required levels across the breeding pipelines. The current review article provides a comprehensive list of genomic regions for enhancing grain Zn and Fe concentrations in wheat including key candidate gene families such NAS, ZIP, VLT, ZIFL, and YSL. Implementing forward breeding by taking advantage of the rapid cycling trait pipeline approaches would simultaneously introgress high Zn and Fe QTL into the high Zn and normal elite lines, further increasing Zn and Fe concentrations

Negative pressure wound therapy: eleven-year experience at a tertiary care hospital

Background: Management of complicated wounds is a reconstructive challenge. A reconstructive surgeon has to be ready to face new challenges every day. Negative pressure wound therapy has revolutionized the management of complex wounds. We are presenting our experience with this wound care modality in the past 11 years.Methods: It was a prospective study conducted from January 2006 to December 2016 on patients having wounds of varied etiologies, who consented to participate in this study. Custom made low cost NPWT was used till definitive wound closure.Results: A total of 568 patients consented to participate in the study during these 11 years. No major complications were seen. Most of these were males (60.73%) in their 3rd and 4th decade. Trauma was the leading cause of wounds in 38.14%, followed by diabetic foot wounds in 21.5%. Ankle and foot was the most common site of wounds (30.92%) followed by leg (24.01%). A total of 322 small, 218 medium and 97 large size dressings were used. Most of the patients improved with the NPWT.  No major complications were seen.Conclusions: NPWT is safe, effective and has proved to be revolutionary in managing difficult wounds. With the use of customized low cost NPWT the benefit can be extended to underprivileged population in under developed nations too

Two stage flexor tendon reconstruction in hand: our experience

Background: Flexor tendon injuries in the digital flexor sheath area (zone II) are the most difficult to treat and remain a focus of both clinical attention and basic investigations. This prospective study was designed to evaluate the results of staged zone II flexor tendon repair.Methods: Seventy digits in thirty five patients were treated by Two Stage flexor tendon reconstruction and followed for an average of one and a half year. The procedure included placing a silicone catheter (cut to desire size) as an active implant and reconstruction of A2, A4 or both pulleys if damaged in first stage. During the second stage (performed three to eight months later), tendon graft replaced the silicone catheter in the pseudo sheath formed around the catheter. The proximal end of the transplanted tendon was fixed with flexor digitorum profundus tendon of respective finger using the Pulvertaft method, and the distal end of the graft was fixedwith the distal stump of respective flexor digitorum profundus tendon. Early controlled motion protocol was instituted in all cases.Results: As per Buck Gramcko scale total active motion obtained was Excellent in 70%, Good in 20%, Fair in 7.1%, and Poor in 2.9% of patients.Conclusions: Flexor tendon reconstruction using two stage tendon reconstructions is an effective way to restore digital tendon function in delayed zone II flexor tendon injuries

Harnessing Genome Editing Techniques to Engineer Disease Resistance in Plants

Modern genome editing (GE) techniques, which include clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) system, transcription activator-like effector nucleases (TALENs), zinc-finger nucleases (ZFNs) and LAGLIDADG homing endonucleases (meganucleases), have so far been used for engineering disease resistance in crops. The use of GE technologies has grown very rapidly in recent years with numerous examples of targeted mutagenesis in crop plants, including gene knockouts, knockdowns, modifications, and the repression and activation of target genes. CRISPR/Cas9 supersedes all other GE techniques including TALENs and ZFNs for editing genes owing to its unprecedented efficiency, relative simplicity and low risk of off-target effects. Broad-spectrum disease resistance has been engineered in crops by GE of either specific host-susceptibility genes (S gene approach), or cleaving DNA of phytopathogens (bacteria, virus or fungi) to inhibit their proliferation. This review focuses on different GE techniques that can potentially be used to boost molecular immunity and resistance against different phytopathogens in crops, ultimately leading to the development of promising disease-resistant crop varieties

Inducing Fungus-Resistance into Plants through Biotechnology

Plant diseases are caused by a variety of plant pathogens including fungi, and their management requires the use of techniques like transgenic technology, molecular biology, and genetics. There have been attempts to use gene technology as an alternative method to protect plants from microbial diseases, in addition to the development of novel agrochemicals and the conventional breeding of resistant cultivars. Various genes have been introduced into plants, and the enhanced resistance against fungi has been demonstrated. These include: genes that express proteins, peptides, or antimicrobial compounds that are directly toxic to pathogens or that reduce their growth in situ; gene products that directly inhibit pathogen virulence products or enhance plant structural defense genes, that directly or indirectly activate general plant defense responses; and resistance genes involved in the hypersensitive response and in the interactions with virulence factors. The introduction of the tabtoxin acetyltransferase gene, the stilbene synthase gene, the ribosome-inactivation protein gene and the glucose oxidase gene brought enhanced resistance in different plants. Genes encoding hydrolytic enzymes such as chitinase and glucanase, which can deteriorate fungal cell-wall components, are attractive candidates for this approach and are preferentially used for the production of fungal disease-resistant plants. In addition to this, RNA-mediated gene silencing is being tried as a reverse tool for gene targeting in plant diseases caused by fungal pathogens. In this review, different mechanisms of fungal disease resistance through biotechnological approaches are discussed and the recent advances in fungal disease management through transgenic approach are reviewed

Genetic Engineering for Viral Disease Management in Plants

Viral diseases are a major threat to world agriculture and breeding resistant varieties against these viruses is one of the major challenge faced by plant virologists and biotechnologists. The development of the concept of pathogen derived resistance gave rise to strategies ranging from coat protein based interference of virus propagation to RNA mediated virus gene silencing. Much progress has been achieved in protecting plants against these RNA and DNA viruses. In this review, the most recent transgene based approaches for viral disease management in plants will be discussed

Conceptualisation, Systematic Review and Future Research Directions in the Broad Domains of Tourism Infrastructure

This paper explored the conceptualisation and research gaps in the field of tourism infrastructure. Key objective of the paper is to define tourism infrastructure and underline the areas explored by researchers and the fields uncharted yet. Systematic overview of existing research is given and briefly showed by details in papers. Articles published between 2007 and upto the end of 2021 has been selected to verify results. The details of author, objectives, methodology and results and conclusions are separated to help budding researchers to identify the research gaps. Nevertheless, the last section briefly describes the areas left untouched by studies for further research. The appraisal conducted shows that certain areas are not properly explored either conceptually, theoretically or empirically. Infrastructure gap is analyzed but the factors determining the functioning of infrastructure unbotched yet. Function of infrastructure to enhance service quality of environment is still unexplored and needs further empirical analysis. At the same time, there is a complete dearth of studies to analyse the contribution of sustainable infrastructure on dimensions of environment sustainability. Lastly, it is confirmed that the accessible literatures botched to give clear practical verification on the influence of tourism infrastructure on services and their influence on tourism resources management. As a result, it is anticipated that the study will add positively in said area and is obliging for lately researchers to conduct studies on uncharted dimensions