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Advances in Plant Defensive Biochemical Activity
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Advances in Plant Defensive Biochemical Activity

A special issue of Life (ISSN 2075-1729). This special issue belongs to the section "Plant Science".

Deadline for manuscript submissions: closed (20 February 2023) | Viewed by 18462

Special Issue Editors

Dr. Mubasher Hussain

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Guest Editor
Guangdong Chinese Academy of Sciences, Guangzhou 510260, China
Interests: microbial ecology; biological control of insect pests; insect molecular biology; applied entomology; chemical ecology; integrated pest management
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Runqian Mao

E-Mail Website
Co-Guest Editor
Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China
Interests: ecology; chemical ecology; molecular biology; medicinal plant sciences
Prof. Dr. Liande Wang

E-Mail Website
Co-Guest Editor
College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Interests: biology; ecology; chemical ecology; molecular ecology; plant sciences
Prof. Dr. Dongliang Qiu

E-Mail Website
Co-Guest Editor
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Interests: agricultural plant science; biotechnology; botany; environmental science; molecular biology
Prof. Dr. Xiansheng Zhang

E-Mail Website
Co-Guest Editor
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
Interests: plant organgenesis; regeneration; stem cell; totipotency

Special Issue Information

Dear Colleagues,

Plant defense compounds act as fingerprints and are essential for specialist herbivores in host plant recognition. Notwithstanding the enormous efforts of academic researchers and the industry, a general solution for a better understanding of the biochemical-mediated defensive response against plant pathogens remains to be found. Therefore, elucidating the role of defensive biochemicals in plants in response to pathogen infection and herbivores may reveal a novel therapeutic strategy to mitigate bacterial diseases. New approaches to bacterial disease control are urgently needed; plant defense chemicals are thus of particular interest for study. This Special Issue will provide an overview of the latest advances in the field of antibacterial plant biochemicals, phytohormones and their applications in a diverse range of areas. This Special Issue will highlight selected papers that detail advances in phytohormonal biosynthesis at molecular and metabolic levels and those that further our understanding of the relationships between defensive biochemicals in plant and their associated phytohormones, particularly in their role against antibacterial activity. 

Potential topics include, but are not limited to:

  • Antibacterial defensive compounds;
  • Bacterial disease;
  • Biochemical-mediated defensive response;
  • Herbivores and host plant recognition;
  • Mechanisms of action of herbivores’ biochemical fingerprints;
  • Plant-associated phytohormones;

Future perspectives for plant defense chemical

Dr. Mubasher Hussain
Prof. Dr. Runqian Mao
Prof. Dr. Liande Wang
Prof. Dr. Dongliang Qiu
Prof. Dr. Xiansheng Zhang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Life is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • antibacterial activity
  • bacterial disease
  • biochemical fingerprints
  • plant defense chemicals
  • pytohormones
  • terpenoids

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Published Papers (8 papers)

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Research

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27 pages, 4234 KiB  
Article
Additive Effect of the Composition of Endophytic Bacteria Bacillus subtilis on Systemic Resistance of Wheat against Greenbug Aphid Schizaphis graminum Due to Lipopeptides
by Sergey D. Rumyantsev, Valentin Y. Alekseev, Antonina V. Sorokan, Guzel F. Burkhanova, Ekaterina A. Cherepanova, Ravil R. Garafutdinov, Igor V. Maksimov and Svetlana V. Veselova
Life 2023, 13(1), 214; https://doi.org/10.3390/life13010214 - 11 Jan 2023
Cited by 11 | Viewed by 2189
Abstract
The use of biocontrol agents based on endophytic bacteria against phloem-feeding insects is limited by a lack of knowledge and understanding of the mechanism of action of the endophyte community that makes up the plant microbiome. In this work, the mechanisms of the [...] Read more.
The use of biocontrol agents based on endophytic bacteria against phloem-feeding insects is limited by a lack of knowledge and understanding of the mechanism of action of the endophyte community that makes up the plant microbiome. In this work, the mechanisms of the additive action of endophytic strains B. subtilis 26D and B. subtilis 11VM on the resistance of bread spring wheat against greenbug aphid Schizaphis graminum, was studied. It was shown that B. subtilis 26D secreted lipopeptide surfactin and phytohormones cytokinins, and B. subtilis 11VM produced iturin and auxins into the cultivation medium. Both strains and their lipopeptide-rich fractions showed direct aphicidal activity against greenbug aphid. For the first time, it was shown that B. subtilis 26D and B. subtilis 11VM in the same manner, as well as their lipopeptide-rich fractions, activated the expression of salicylate- and ethylene-dependent PR genes, and influenced plant redox metabolism, which led to an increase in plant endurance against aphids. The composition of endophytic strains B. subtilis 26D + B. subtilis 11VM had an additive effect on plant resistance to aphids due to an increase in the number of endophytic bacterial cells, and, as well as due to the synergistic effect of their mixture of lipopeptides − surfactin + iturin, both on the aphid mortality and on the expression of PR1 and PR3 genes. All these factors can be the reason for the observed increase in the growth of plants affected by aphids under the influence of B. subtilis 26D and B. subtilis 11VM, individually and in composition. The study demonstrates the possibility of creating in the future an artificial composition to enhance plant microbiome with endophytic bacteria, which combines growth-promoting and plant immunity stimulating properties against phloem-feeding insects. This direction is one of the most promising approaches to green pesticide discovery in the future. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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14 pages, 2378 KiB  
Article
The Cellular Immunological Responses and Developmental Differences between Two Hosts Parasitized by Asecodes hispinarum
by Zhiming Chen, Tingting Fu, Lang Fu, Bin Liu, Yaping Lin, Baozhen Tang and Youming Hou
Life 2022, 12(12), 2025; https://doi.org/10.3390/life12122025 - 4 Dec 2022
Cited by 2 | Viewed by 1631
Abstract
This study aims to investigate the developmental interactions of Asecodes hispinarum Bouček on Brontispa longissima Gestro and Octodonta nipae Maulik, as well as the cellular immune responses of B. longissima and O. nipae larvae in response to parasitism by A. hispinarum, with [...] Read more.
This study aims to investigate the developmental interactions of Asecodes hispinarum Bouček on Brontispa longissima Gestro and Octodonta nipae Maulik, as well as the cellular immune responses of B. longissima and O. nipae larvae in response to parasitism by A. hispinarum, with the hope of determining the reason for the difference in larval breeding of A. hispinarum in B. longissima and O. nipae. The effects of parasitism by A. hispinarum on the larval development, hemocyte count, and proportion of the hemocyte composition of the two hosts were carried out through selective assay and non-selective assay using statistical analysis and anatomical imaging. There was no significant difference in parasitic selection for A. hispinarum on the larvae of these two beetles; however, more eggs were laid to B. longissima larvae than to O. nipae larvae after parasitism by A. hispinarum. The eggs of A. hispinarum were able to grow and develop normally inside the larvae of B. longissima, and the parasitism caused the larvae of B. longissima become rigid within 7 d, with a high larval mortality rate of 98.88%. In contrast, the eggs of A. hispinarum were not able to develop normally inside the O. nipae larvae, with a high encapsulation rate of 99.05%. In addition, the parasitism by A. hispinarum caused a 15.31% mortality rate in O. nipae larvae and prolonged the larval stage by 5 d and the pupal stage by 1 d. The number of hemocytes during the 12, 24, 48, 72, and 96 h of the four instars from O. nipae larvae was 6.08 times higher than from B. longissima larvae of the same age. After 24 h of being parasitized by A. hispinarum, the total number of hemocytes and granulocyte proportion of B. longissima larvae increased significantly. However, the total number of hemocytes and plasmatocyte proportion of O. nipae increased significantly after 24, 72, and 96 h, and the proportion of granulocytes increased significantly after 12 h post-parasitism. The results in the present study indicated that A. hispinarum was unable to successfully reproduce offspring in O. nipae, but its spawning behavior had an adverse effect on the larval development of its host. In addition, the adequate number of hemocytes and more pronounced changes in the hemocyte count and hemocyte composition ratio in the larvae after parasitization may be important factors for the successful encapsulation in O. nipae larvae. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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12 pages, 2336 KiB  
Article
Functional Characterization of the Ryanodine Receptor Gene in Diaphorina citri
by Tian-Sheng Liu, Xue-Li Sun, Min-Liang Bin, Gan-Jun Yi and Xin-Xin Zhang
Life 2022, 12(12), 2005; https://doi.org/10.3390/life12122005 - 1 Dec 2022
Cited by 2 | Viewed by 1478
Abstract
The Asian citrus psyllid Diaphorina citri (Hemiptera: Liviidae) is a major citrus pest spread around the world. It is also a vector of the bacterium ‘Candidatus Liberibacter asiaticus’, considered the cause of the fatal citrus disease huanglongbing (HLB). Insect ryanodine receptors (RyRs) [...] Read more.
The Asian citrus psyllid Diaphorina citri (Hemiptera: Liviidae) is a major citrus pest spread around the world. It is also a vector of the bacterium ‘Candidatus Liberibacter asiaticus’, considered the cause of the fatal citrus disease huanglongbing (HLB). Insect ryanodine receptors (RyRs) are the primary target sites of diamide insecticides. In this study, full-length RyR cDNA from D. citri (named DcRyR) was isolated and identified. The 15,393 bp long open reading frame of DcRyR encoded a 5130 amino acid protein with a calculated molecular weight of 580,830 kDa. This protein had a high sequence identity (76–79%) with other insect homologs and a low sequence identity (43–46%) with mammals. An MIR domain, two RIH domains, three SPRY domains, four RyR repeat domains, an RIH-associated domain at the N-terminus, two consensus calcium-binding EF-hands, and six transmembrane domains were among the characteristics that DcRyR shared with insect and vertebrate RyRs. In expression analysis, the DcRyR gene displayed transcript abundance in all tissues and developmental stages as well as gene-differential and stage-specific patterns. In addition, diagnostic PCR experiments revealed that DcRyR had three potential alternative splice variants and that splicing events might have contributed to the various functions of DcRyR. However, diamide resistance-related amino acid residue mutations I4790M/K and G4946E were not found in DcRyR. These results can serve as the basis for further investigation into the target-based diamide pesticide resistance of D. citri. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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11 pages, 1956 KiB  
Article
Assessing the Bacterial Communities Composition from Differently Treated Agarwood via 16S rRNA Gene Metabarcoding
by Yichen Wang, Mubasher Hussain, Xincheng An, Xiaojun Jiang and Runqian Mao
Life 2022, 12(11), 1697; https://doi.org/10.3390/life12111697 - 25 Oct 2022
Cited by 2 | Viewed by 2136
Abstract
Agarwood (Aquilaria sinensis) is one of the most important resin-containing plants used to produce agar around the world and it is a precious herbal medicine usually combined with other herbs. In this study, we used the Illumina sequencing technique to explore [...] Read more.
Agarwood (Aquilaria sinensis) is one of the most important resin-containing plants used to produce agar around the world and it is a precious herbal medicine usually combined with other herbs. In this study, we used the Illumina sequencing technique to explore the agarwood bacterial community structure from four different incense formations of agarwood, including healthy agarwood, drilling agarwood, liquid fermentation agarwood, and insect attack agarwood. Our results showed that 20 samples of three different incense-formation methods of agarwood and healthy agarwood acquired 1,792,706 high-quality sequences. In-depth investigation showed that when the diversity of agarwood bacterial species was higher, the agarwood incense quality was higher as well. Among healthy agarwood, drilling agarwood, fermentation agarwood, and insect attack agarwood, the bacterial community structure had significant changes. Natural agarwood, such as insect attack agarwood, kept more bacterial community structure, and the incense quality was better. Furthermore, we observed that in the healthy agarwood, Amnibacterium and Delftia were the predominant bacteria. Actinoplanes, Bordetella, and Sphingobacterium were the dominant bacteria in the drilling agarwood. Additionally, Pelagibacterium and Methylovirgula were some of the main bacteria in the fermentation liquid agarwood and the insect attack agarwood, while Cellulomonas and Aeromicrobium were the dominant bacteria. This research provides a basis for further research into the underlying mechanisms of incense production, as well as the bacterial community applications of agarwood production. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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17 pages, 2972 KiB  
Article
Genome Organization and Comparative Evolutionary Mitochondriomics of Brown Planthopper, Nilaparvata lugens Biotype 4 Using Next Generation Sequencing (NGS)
by Guru-Pirasanna-Pandi Govindharaj, Soumya Bharti Babu, Jaipal Singh Choudhary, Muhammad Asad, Parameswaran Chidambaranathan, Basana-Gowda Gadratagi, Prakash Chandra Rath, Naiyar Naaz, Mariusz Jaremko, Kamal Ahmad Qureshi and Uttam Kumar
Life 2022, 12(9), 1289; https://doi.org/10.3390/life12091289 - 23 Aug 2022
Cited by 2 | Viewed by 2172
Abstract
Nilaparvata lugens is the main rice pest in India. Until now, the Indian N. lugens mitochondrial genome has not been sequenced, which is a very important basis for population genetics and phylogenetic evolution studies. An attempt was made to sequence two examples of [...] Read more.
Nilaparvata lugens is the main rice pest in India. Until now, the Indian N. lugens mitochondrial genome has not been sequenced, which is a very important basis for population genetics and phylogenetic evolution studies. An attempt was made to sequence two examples of the whole mitochondrial genome of N. lugens biotype 4 from the Indian population for the first time. The mitogenomes of N. lugens are 16,072 and 16,081 bp long with 77.50% and 77.45% A + T contents, respectively, for both of the samples. The mitochondrial genome of N. lugens contains 37 genes, including 13 protein-coding genes (PCGs) (cox1-3, atp6, atp8, nad1-6, nad4l, and cob), 22 transfer RNA genes, and two ribosomal RNA (rrnS and rrnL) subunits genes, which are typical of metazoan mitogenomes. However, both samples of N. lugens mitogenome in the present study retained one extra copy of the trnC gene. Additionally, we also found 93 bp lengths for the atp8 gene in both of the samples, which were 60–70 bp less than that of the other sequenced mitogenomes of hemipteran insects. The phylogenetic analysis of the 19 delphacids mitogenome dataset yielded two identical topologies when rooted with Ugyops sp. in one clade, and the remaining species formed another clade with P. maidis and M. muiri being sisters to the remaining species. Further, the genus Nilaparvata formed a separate subclade with the other genera (Sogatella, Laodelphax, Changeondelphax, and Unkanodes) of Delphacidae. Additionally, the relationship among the biotypes of N. lugens was recovered as the present study samples (biotype-4) were separated from the three biotypes reported earlier. The present study provides the reference mitogenome for N. lugens biotype 4 that may be utilized for biotype differentiation and molecular-aspect-based future studies of N. lugens. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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14 pages, 839 KiB  
Article
Plant Volatile Compounds of the Invasive Alligatorweed, Alternanthera philoxeroides (Mart.) Griseb, Infested by Agasicles hygrophila Selman and Vogt (Coleoptera: Chrysomelidae)
by Meng-Zhu Shi, Jian-Yu Li, Yan-Ting Chen, Ling Fang, Hang Wei and Jian-Wei Fu
Life 2022, 12(8), 1257; https://doi.org/10.3390/life12081257 - 17 Aug 2022
Cited by 1 | Viewed by 1955
Abstract
Plants release a variety of volatiles and herbivore-induced plant volatiles (HIPVs) after being damaged by herbivorous insects, which play multiple roles in the interactions with other plants and insects. Agasicles hygrophila Selman and Vogt (Coleoptera: Chrysomelidae) is a monophagous natural enemy and an [...] Read more.
Plants release a variety of volatiles and herbivore-induced plant volatiles (HIPVs) after being damaged by herbivorous insects, which play multiple roles in the interactions with other plants and insects. Agasicles hygrophila Selman and Vogt (Coleoptera: Chrysomelidae) is a monophagous natural enemy and an effective biocontrol agent for Alternanthera philoxeroides (Mart.) Griseb. Here, we reported differences among the volatiles of A. philoxeroides by solid phase microextraction (SPME) using a gas chromatography-mass spectrometer (GC-MS). We compared the volatile emission of: (1) clean plants (CK); (2) A. philoxeroides plants with mechanical damage treatment (MD); and (3) A. philoxeroides plants infested with A. hygrophila 1st, 2nd, and 3rd larvae and female and male adults. A total of 97 volatiles were recorded, of which 5 occurred consistently in all treatments, while 61 volatiles were only observed in A. philoxeroides infested by A. hygrophila, such as trans-nerolidol, (E)-β-farnesene, and (3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (E, E-TMTT), etc. Among the 97 volatile compounds, 37 compounds belong to alkenes, 29 compounds belong to alkanes, and there were 8 esters, 8 alcohols and 6 ketones. Orthogonal partial least squares-discrimination analysis (OPLS-DA) showed that the different treatments were separated from each other, especially insect feeding from CK and MD treatments, and 19 volatiles contributed most to the separation among the treatments, with variable importance for the projection (VIP) values > 1. Our findings indicated that the alligatorweed plants could be induced to release volatiles by different stages of A. hygrophila, and the volatile compounds released differ quantitatively and qualitatively. The results from this study laid an important foundation for using volatile organic compounds (VOCs) and HIPVs of alligatorweed to improve the control effect of A. hygrophila on A. philoxeroides. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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16 pages, 2955 KiB  
Article
The Entomopathogenic Nematodes H. bacteriophora and S. carpocapsae Inhibit the Activation of proPO System of the Nipa Palm Hispid Octodonta nipae (Coleoptera: Chrysomelidae)
by Nafiu Bala Sanda, Bofeng Hou and Youming Hou
Life 2022, 12(7), 1019; https://doi.org/10.3390/life12071019 - 9 Jul 2022
Cited by 1 | Viewed by 2019
Abstract
Entomopathogenic nematodes are biocontrol agents of invasive insect pests in soil and cryptic habitats. Nipa palm hispid, Octodonta nipae, is a pest of palm trees in Sothern China. To address its increasing damage, environmentally friendly control methods are required. This study aimed [...] Read more.
Entomopathogenic nematodes are biocontrol agents of invasive insect pests in soil and cryptic habitats. Nipa palm hispid, Octodonta nipae, is a pest of palm trees in Sothern China. To address its increasing damage, environmentally friendly control methods are required. This study aimed to test efficacy of Heterorhabditis bacteriophora and Steinernema carpocapsae on O. nipae and investigated the influence of secondary metabolites, nematodes, and their isolated cuticles on the activation of O. nipae’s prophenoloxidase system using qPCR analysis. Our data revealed that O. nipae were less susceptible to H. bacteriophora than S. carpocapsae and penetrations of infective juveniles were higher with S. carpocapsae treatment than H. bacteriophora. Moreover, expression levels of the serine protease P56, prophenoloxidase activation factor 1, PPO and serine protease inhibitor 28 upon S. carpocapsae and H. bacteriophora infections were generally downregulated at all times. However, upon heating, the cuticles lost their inhibitory effects and resulted in upregulation of the PPO gene. Similarly, the addition of arachidonic acid reversed the process and resulted in the upregulation of the PPO gene compared to the control. Further work is needed to identify toxic substances secreted by these EPNs to evade O. nipae’s immune system. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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17 pages, 1020 KiB  
Review
Molecular and Biochemical Mechanisms of Elicitors in Pest Resistance
by Saif ul Malook, Saiqa Maqbool, Muhammad Hafeez, Samantha Chandranath Karunarathna and Nakarin Suwannarach
Life 2022, 12(6), 844; https://doi.org/10.3390/life12060844 - 6 Jun 2022
Cited by 10 | Viewed by 3498
Abstract
Insect herbivores have a variety of life cycles and feeding habits, making them extremely diverse. With their host plants, they form close relationships and suppress their defense mechanisms. Molecular elicitors are the key bio-elements in the detection and recognition of attacking enemies in [...] Read more.
Insect herbivores have a variety of life cycles and feeding habits, making them extremely diverse. With their host plants, they form close relationships and suppress their defense mechanisms. Molecular elicitors are the key bio-elements in the detection and recognition of attacking enemies in tissue consumption. Insect oral secretion, frass, and fluid of egg deposition contain biologically active molecules called herbivore-associated elicitors (HAEs) that are recognized by pattern-recognition receptors (PRRs). Many plants distinguish insect feeding from wounding by HAEs present in their oral secretions (OS) and induce local and/or systemic responses against arthropod feeding. PRRs perceive HAEs in the oral secretion of caterpillars in a species-specific manner to elicit exclusive defense responses. HAEs-PRRs interactions induce plant resistance by reprogramming plant metabolism and transcriptional machinery. Quantitative, timely, and coordinated plant response initiate early signaling events, including Ca2+, reactive oxygen species (ROS), and mitogen-activated protein kinases (MAPKs). However, in insect herbivory, little is known about the molecular basis of signal transduction and regulation of plant resistance. We discuss here how early signaling cascades converge into the accumulation of phytohormones that regulate downstream special metabolites against herbivores. In this review, we propose a hypothetical model of PPRs-HAEs-mediated-induced responses in plants and discuss how PRRs-HAEs interactions elicit short- and long-term induced defenses in plants. The understanding of PRRs-HAEs interactions will help to explore the fundamental molecular mechanisms of host manipulation and may generate prospects to develop novel pest-resistance strategies. Full article
(This article belongs to the Special Issue Advances in Plant Defensive Biochemical Activity)
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