Worldwide Research on Plant Defense against Biotic Stresses as Improvement for Sustainable Agriculture

Agriculture is the basis for food production on a global scale. Sustainable agriculture tries to improve or maintain the quality of food without compromising the environment. As sessile organisms, plants cannot avoid adverse environmental conditions and contact with other living organisms. The damage caused to plants by other living organisms such as parasites and pathogens (virus, bacteria, fungi, nematodes or insects) brings about what is known as biotic stress. Plants are constantly exposed to biotic stress, which causes changes in plant metabolism involving physiological damages that lead to a reduction of their productivity. To fight biotic stress, plants have developed sophisticated defense mechanisms. Thus, understanding plant defense mechanisms might prevent important crop and economic losses. In this article, a bibliometric analysis of biotic stress is carried out. Different aspects of the publications are analyzed, such as publication type, research field, journal type, countries and their institutions, as well as the keyword occurrence frequency, and finally special attention is paid to the plant studied by the leading countries and institutions. As expected, journals selected by authors to publish their relevant findings are plant-specific journals. However, it should be noted that the fourth position, in terms of the number of publications per journal, is occupied by BMC Genomics journal. Such a journal considers mainly articles on genomics, which indicates the involvement of genetic factors in the control of biotic stress. Analysis of the keywords used in publications about biotic stress shows the great interest in the biotic–abiotic stress interaction, in the gene expression regulation in plants as well as phytohormones in the current research. In short, the great effort made by the scientific community in the biotic and abiotic stresses field with the aim to understand, regulate and control plant damages caused by biotic stress agents will help in the development of sustainable agriculture

Response of BVOC emissions from Fraxinus excelsior to biotic stress

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Proteomics-based dissection of biotic stress responsive proteins in bread wheat (Triticum aestivum L.)

Proteomic techniques that allow the identification and quantification of stress-related proteins, mapping dynamics of their expression and post translational modifications represent an important approach in the research of plant stresses. Biotic stress is one of the major stresses limiting crop productivity and the geographical distribution of many important crops worldwide. Two hundred and seventeen protein spots reproducibly were detected from six gels by using two-dimensional electrophoresis. After tryptic digestion, MALDI-TOF/MS analysis and database searching of some of the identified proteins indicated that the proteins are known to be involved in several biotic stress related functions as disease associate with pathogens. Mass spectrometry analysis allowed the identification of 185 differential expressed proteins with isoforms including well known biotic stress  esponsive proteins. Keumgang (13%), Jinpum (8%), China-108 (14%), Yeonnon-67 (11%), Norin-61 (22%) and Kantou-107 (32%) were identified as biotic stress responses proteins directly coupled to disease and pathogen infection on wheat. Nevertheless, our studies provides new insights into identification of biotic stress responses protein in disease infected wheat grain by natural condition, the post-translational modification in  protein sequences, verify eventual differences among the genotypes in relation to them, and demonstrates the advantages of proteomic analysis.Key words: Biotic stress, matrix-assisted laser desorption ionization-time of flight, proteomics, posttranslational modification, two-dimensional electrophoresis, wheat

Exogén SA kezelések fényben és sötétben történő hatásának összehasonlító elemzése vad típusú és etilén receptor mutáns, Never-ripe paradicsom növények leveleiben

Biotic stresses is caused in plants due to damage instigated by other organisms, like insects, disease (fungal, bacterial, and viral), which are major limitations to crop yield. The cellular response to biotic stress is an oxidative and nitrosative burst involving production of reactive oxygen species (ROS) and nitric oxide (NO). Salicylic acid (SA) is a natural phenolic compound, which accumulates under biotic stress and controls physiological and biochemical functions in plants. SA plays an important role in oxidative and nitrosative stress by modulating the activity of some antioxidant enzymes. Polyamines (PAs) are low molecular weight organic compounds acting as signal molecules by directly or indirectly involved in the biotic stress response pathway. The metabolism of PAs is regulated not just by SA but also by the gaseous phytohormone ethylene (ET), which is a key regulator in plant growth and developmental process as well as biotic stress response. Furthermore, ET and PAs may be an antagonistic relationship because they share a common biosynthetic precursor. However, plant immune defence also depends on the environmental factors such as light. Excess of light energy under stress conditions leads to oxidative stress, which may contribute to the initiation of cell death in tissues

Updated Rice Kinase Database RKD 2.0: enabling transcriptome and functional analysis of rice kinase genes

Rice kinases with biotic stress responses. (XLSX 28 kb

Farmers\u27 Perception on the Performance of Different Rice Varieties in Kapilvastu District, Nepal

Rice is the major staple food crop in Nepal. To date, several rice varieties have been developed and released in Nepal. However, rice production is far below in comparison with its production potential. A household survey was conducted in Bangaganga municipality of Kapilvastu district in 2018 to assess farmers\u27 perception on performance of four different rice varieties (Radha-4, Ramdhan, Gorakhnath, and Sawa). The data were collected from a total of 120 rice farmers (randomly selected) using the interview schedule and analyzed using descriptive statistics, Likert scale, and indexing technique. Statistical analysis showed that the Ramdhan variety had the highest yield (4.95 t/ha), whereas Radha-4 had the lowest yield (3.15 t/ha). The most disease and drought-tolerant variety, as perceived by the farmers, was Radha-4. Smut and Khaira were perceived as the primary diseases whereas Brown planthopper and Rice Gundhi bug were the most important insects of all studied rice varieties. The study recommended that the plant breeders should focus on developing site-specific rice varieties to meet the multiple concerns of the farmers, such as higher yield and stress-tolerant. The farmers should be made aware of varietal selection and crop pest management techniques via training programs, which further helps to reduce the yield gap between farmers\u27 field and research field

Effect of elevated atmospheric CO2 level on the abiotic and biotic stress tolerance of cereals

Abstract Effect of elevated CO2 level (EC) was studied on the tolerance of cereals to elevated temperature and drought and on the resistance of wheat to fungal diseases. In general, elevated growth temperature did not affect final grain size, thus having less harmful effects than heat stress or drought during grain-filling. The plants subjected to low water supply levels or elevated temperature had higher biomass and grain yield at EC than at the ambient level. Susceptible wheat varieties were, however, usually more prone to diseases when grown at EC, while resistant varieties remained resistant even at EC

Emerging connections between small RNAs and phytohormones

Small RNAs (sRNAs), mainly including miRNAs and siRNAs, are ubiquitous in eukaryotes. sRNAs mostly negatively regulate gene expression via (post-)transcriptional gene silencing through DNA methylation, mRNA cleavage, or translation inhibition. The mechanisms of sRNA biogenesis and function in diverse biological processes, as well as the interactions between sRNAs and environmental factors, like (a)biotic stress, have been deeply explored. Phytohormones are central in the plant’s response to stress, and multiple recent studies highlight an emerging role for sRNAs in the direct response to, or the regulation of, plant hormonal pathways. In this review, we discuss recent progress on the unraveling of crossregulation between sRNAs and nine plant hormones

Predictability of biotic stress structures plant defence evolution

To achieve ecological and reproductive success, plants need to mitigate a multitude of stressors. The stressors encountered by plants are highly dynamic but typically vary predictably due to seasonality or correlations among stressors. As plants face physiological and ecological constraints in responses to stress, it can be beneficial for plants to evolve the ability to incorporate predictable patterns of stress in their life histories. Here, we discuss how plants predict adverse conditions, which plant strategies integrate predictability of biotic stress, and how such strategies can evolve. We propose that plants commonly optimise responses to correlated sequences or combinations of herbivores and pathogens, and that the predictability of these patterns is a key factor governing plant strategies in dynamic environments.</p