Stages Of Plant Development Research Articles

Litter facilitates plant development but restricts seedling establishment during vegetation regeneration

Abstract Rapid vegetation regeneration and increased litter production have been predicted under the global greening scenario, but the overall relationship between litter production and vegetation regeneration has not been well addressed. To bridge this knowledge gap, we quantified the responses of the seed stage, seedling stage, plant development stage and vegetation community to litter using 3193 paired observations at the global scale based on the effect size across different categories. Overall, litter significantly decreased seedling establishment and density by 28.4% and 27.7%, increased plant height by 17.4% and decreased species richness by 15.4%. Seed germination at the seed stage was not directly controlled by litter but was positively regulated by changes in soil moisture from litter. In contrast, litter type and litter mass displayed negative effects on the seedling stage, but litter promoted seedling survival with increasing elevation. Moreover, litter composition and plant type dominated the effects of litter on the plant development stage, showing that the increase in litter production might favour the development of broadleaved trees rather than other plants. The present results suggest that litter could restrict the stage from seed to seedling but facilitate plant development after the seedling establishment and slightly affect the vegetation community except for species richness. These results provide deep insight into the relationships between litter production and vegetation regeneration at different stages, which are important for developing models accounting for vegetation regeneration responses to ongoing global greening. Read the free Plain Language Summary for this article on the Journal blog.

The Growth-promoting and Antipathogenic Effects of Microorganisms Isolated from Solanum nigrum L. and Inoculated in Solanum lycopersicum L.

Background: In recent years, there has been a growing scientific interest in the biodiversity and function of endophytic bacteria, as well as the prospects for their practical use. Objective: The purpose of this work was to isolate endophytic microorganisms from generative organs of the European black nightshade (Solanum nigrum L.), assess their biological activity, and test their growth-promoting/protective effects in tomato (Solanum lycopersicum L.) plants. Methods: From the tissues of generative organs of S. nigrum plants, 14 strains of endophytic microorganisms were isolated. Most of them belonged to Bacillus sp. The physiological and biochemical properties and enzymatic and oxidative metabolism of some of them were studied. Sequence analysis of 16S rRNA fragments revealed 99,65% similarity of BA1s-OSN-0820 and BAXS-OSN-0820 isolates to B. amyloliquefaciens strains, while the ITS sequence of the RHC-OSN-0820 isolate showed 99,65% of similarity to Rhodotorula kratochvilovae. Results: The actions of these endophytes against tomato pathogenic bacteria and fungi were then tested. The isolates had a significant bacteriostatic effect against Xanthomonas campestris, the causative agent of black bacterial spotting of leaf, and Clavibacter michiganensis, the causative agent of bacterial wilt, with a lower effect against Pseudomonas syringae, the causative agent of bacterial spotting. Isolates also showed selectivity against micromycetes that cause mycosis in tomatoes grown indoors, such as Fusarium oxysporum, Alternaria solani, Botrytis cinerea, Sclerotinia sclerotiorum, and F. acuminatum. In particular, the highest antifungal activity was detected against S. sclerotiorum and fungi of the Fusarium genus. Inoculation of tomatoes with endophytic microorganisms revealed a positive effect on seed germination efficiency and the stimulation of seedling growth. Thus, the effectiveness of interspecific transfer of endophytic microorganisms from a wild, S. nigrum, to a cultivated Solanum species, S. lycopersicum, was reported. Conclusion: A consortium of plant-associated microorganisms isolated from a wild relative has a positive effect on the germination of tomato seeds, stimulating the formation of the root system and nutrition of seedlings. The antagonism of the isolates against phytopathogenic fungi and bacteria provides long-term protection during the most critical stages of plant development and has prospects for the development of microbial biologics for cultivated plants of the Solanaceae family.

Environmental microbiology going computational-Predictive ecology and unpredicted discoveries.

Environmental microbiology going computational-Predictive ecology and unpredicted discoveries.

Microbiomes in agroecosystem: Diversity, function and assembly mechanisms.

Soils are a main repository of biodiversity harbouring immense diversity of microbial species that plays a central role in fundamental ecological processes and acts as the seed bank for emergence of the plant microbiome in cropland ecosystems. Crop-associated microbiomes play an important role in shaping plant performance, which includes but not limited to nutrient uptake, disease resistance, and abiotic stress tolerance. Although our understanding of structure and function of soil and plant microbiomes has been rapidly advancing, most of our knowledge comes from ecosystems in natural environment. In this review, we present an overview of the current knowledge of diversity and function of microbial communities along the soil-plant continuum in agroecosystems. To characterize the ecological mechanisms for community assembly of soil and crop microbiomes, we explore how crop host and environmental factors such as plant species and developmental stage, pathogen invasion, and land management shape microbiome structure, microbial co-occurrence patterns, and crop-microbiome interactions. Particularly, the relative importance of deterministic and stochastic processes in microbial community assembly is illustrated under different environmental conditions, and potential sources and keystone taxa of the crop microbiome are described. Finally, we highlight a few important questions and perspectives in future crop microbiome research.

A perspective view of nitric oxide: biosynthesis, metabolism and signaling in plants

<p indent="0mm">Nitric oxide (NO) is an important gaseous signaling molecule widely distributed in living organisms, it modulates protein stability and enzyme activities mainly through post-translational modifications, including <italic>S</italic>-nitrosylation and tyrosine nitration. NO regulates multiple physiological processes during plant development and stress responses. Moreover, the complex interplay among NO and phytohormones, reactive oxygen species and other signaling molecules precisely regulates various stages of plant growth and development to maintain normal life activities. Here, we review the synthesis and metabolism of NO, and provide insights into the mechanism and biological significance of NO in the regulation of plant development and stress responses.

Dispersal kernel of green rice leafhopper estimated from truncated data

AbstractCharacterizing dispersal kernels from truncated data is important for managing and predicting population dynamics. We used mark‐recapture data from 10 previously published replicated experiments at three host plant development stages (seedling, tillering, and heading) to estimate parameters of the normal and exponential dispersal kernels for green rice leafhopper,Nephotettix cincticeps(Uhler). We compared classic statistical methods for estimating untruncated distribution parameters from truncated data with maximum likelihood (MLE) and the method of statistical moments for simulated and empirical data. Simulations showed that both methods provided accurate parameter estimates with similar precision. The method of moments is algebraically complex, but simple to calculate, while the MLE methods require numerical solutions of nonlinear equations. Simulations also showed that accurate, precise estimates of the parameters of the untruncated distributions could be attained even under severe truncation with sufficient numbers of recaptures. Both diffusivity and the exponential mean were higher with later plant growth stage, showing that insects moved farther and faster at the heading stage. Precision of the estimates was not strongly related to percent capture, size of the experimental field, or the number of leafhoppers captured. The leptokurtic exponential kernel fit the data better than the normal kernel for all the experiments. These results support an alternative explanation for the strong density‐dependent population regulation of this species at the heading stage. Instead of leafhopper density per se, the increase in movement at this stage could integrate the populations in the separate fields, leveling densities throughout the landscape.

INFLUENCE OF FORECROPS AND SUPPLEMENTARY FERTILIZATION OF WINTER WHEAT AT DIFFERENT PERIODS OF ITS VEGETATION ON YIELD FORMATION AND GRAIN QUALITY

Research on the study of effectiveness of nitrogen fertilization on productivity and quality of winter wheat grain was conducted in the conditions of the Volga region in 2017-2021. A two-factor experiment was set on leached heavy loamy black soil (humus - 6.5% by Tyurin; pH of the salt extract - 6.3-6.5; P2O5 - 185-216; K2O - 80-85 mg per 1 kg of soil) according to the following scheme: I - forecrop (factor A): complete and sown fallow; II. fertilization with ammonium nitrate (factor B): 1. control (N0); 2. autumn (N34); 3 with a seeder (N34); 4. early spring (N34); 5 early spring (N34) + at the shooting stage (N34); 6 early spring (N34) + at the shooting stage (N34) + N15at the heading phase. Lack of moisture at the start of the experiments did not allow to obtain friendly seedlings (complete fallow - 75.9-78.3%, sown - 71.7-75.2%). Frequent temperature fluctuations at the beginning of the vegetation season and lack of precipitation during the period of grain filling had a negative impact on survivability of plants by the harvesting time (complete fallow - 44.9-50.3%, sown - 29.2-34.2%). The highest grain yield (4.48 t/ha) was formed when winter wheat was sown on complete fallow in combination with fertilizer application (N34+N34+N15), which exceeded the control by 1.11 t/ha (34.9%). High content of protein (13.7%) and gluten (31.8%) provided the variant with early spring fertilization in a scattered way at a dose of N34. An increase offertilization frequency led to a decrease of protein (13.3%) and gluten (30.4%). Cultivation of winter wheat on sown fallow reduced yield by 1.19 t/ha (36.2%) and quality parametres (protein 12.2%, gluten 26.9%) of the grain. The highest net operating profit (25,883 rubles/ha) and high profitability (136.8%) of the grain were obtained when sown on complete fallow in combination with fractional fertilization at different stages of plant development. The cost of 1 ton of grain was 4220 rubles.

Arabidopsis Ubiquitin-Conjugating Enzymes UBC4, UBC5, and UBC6 Have Major Functions in Sugar Metabolism and Leaf Senescence.

The ubiquitin-conjugating enzyme (E2) is required for protein ubiquitination. Arabidopsis has 37 E2s grouped into 14 subfamilies and the functions for many of them are unknown. We utilized genetic and biochemical methods to study the roles of Arabidopsis UBC4, UBC5, and UBC6 of the E2 subfamily IV. The Arabidopsis ubc4/5/6 triple mutant plants had higher levels of glucose, sucrose, and starch than the control plants, as well as a higher protein level of a key gluconeogenic enzyme, cytosolic fructose 1,6-bisphosphatase 1 (cyFBP). In an in vitro assay, the proteasome inhibitor MG132 inhibited the degradation of recombinant cyFBP whereas ATP promoted cyFBP degradation. In the quadruple mutant ubc4/5/6 cyfbp, the sugar levels returned to normal, suggesting that the increased sugar levels in the ubc4/5/6 mutant were due to an increased cyFBPase level. In addition, the ubc4/5/6 mutant plants showed early leaf senescence at late stages of plant development as well as accelerated leaf senescence using detached leaves. Further, the leaf senescence phenotype remained in the quadruple ubc4/5/6 cyfbp mutant. Our results suggest that UBC4/5/6 have two lines of important functions, in sugar metabolism through regulating the cyFBP protein level and in leaf senescence likely through a cyFBP-independent mechanism.

A seed-like proteome in oil-rich tubers.

There are numerous examples of plant organs or developmental stages that are desiccation-tolerant and can withstand extended periods of severe water loss. One prime example are seeds and pollen of many spermatophytes. However, in some plants, also vegetative organs can be desiccation-tolerant. One example are the tubers of yellow nutsedge (Cyperus esculentus), which also store large amounts of lipids similar to seeds. Interestingly, the closest known relative, purple nutsedge (Cyperus rotundus), generates tubers that do not accumulate oil and are not desiccation-tolerant. We generated nanoLC-MS/MS-based proteomes of yellow nutsedge in five replicates of four stages of tuber development and compared them to the proteomes of roots and leaves, yielding 2257 distinct protein groups. Our data reveal a striking upregulation of hallmark proteins of seeds in the tubers. A deeper comparison to the tuber proteome of the close relative purple nutsedge (C. rotundus) and a previously published proteome of Arabidopsis seeds and seedlings indicates that indeed a seed-like proteome was found in yellow but not purple nutsedge. This was further supported by an analysis of the proteome of a lipid droplet-enriched fraction of yellow nutsedge, which also displayed seed-like characteristics. One reason for the differences between the two nutsedge species might be the expression of certain transcription factors homologous to ABSCISIC ACID INSENSITIVE3, WRINKLED1, and LEAFY COTYLEDON1 that drive gene expression in Arabidopsis seed embryos.

Chemical priming enhances plant tolerance to salt stress.

Salt stress severely limits the productivity of crop plants worldwide and its detrimental effects are aggravated by climate change. Due to a significant world population growth, agriculture has expanded to marginal and salinized regions, which usually render low crop yield. In this context, finding methods and strategies to improve plant tolerance against salt stress is of utmost importance to fulfill food security challenges under the scenario of the ever-increasing human population. Plant priming, at different stages of plant development, such as seed or seedling, has gained significant attention for its marked implication in crop salt-stress management. It is a promising field relying on the applications of specific chemical agents which could effectively improve plant salt-stress tolerance. Currently, a variety of chemicals, both inorganic and organic, which can efficiently promote plant growth and crop yield are available in the market. This review summarizes our current knowledge of the promising roles of diverse molecules/compounds, such as hydrogen sulfide (H2S), molecular hydrogen, nitric oxide (NO), hydrogen peroxide (H2O2), melatonin, chitosan, silicon, ascorbic acid (AsA), tocopherols, and trehalose (Tre) as potential primers that enhance the salinity tolerance of crop plants.

The Role of Medicago lupulina Interaction with Rhizophagus irregularis in the Determination of Root Metabolome at Early Stages of AM Symbiosis.

The nature of plant–fungi interaction at early stages of arbuscular mycorrhiza (AM) development is still a puzzling problem. To investigate the processes behind this interaction, we used the Medicago lupulina MlS-1 line that forms high-efficient AM symbiosis with Rhizophagus irregularis. AM fungus actively colonizes the root system of the host plant and contributes to the formation of effective AM as characterized by a high mycorrhizal growth response (MGR) in the host plant. The present study is aimed at distinguishing the alterations in the M. lupulina root metabolic profile as an indicative marker of effective symbiosis. We examined the root metabolome at the 14th and 24th day after sowing and inoculation (DAS) with low substrate phosphorus levels. A GS-MS analysis detected 316 metabolites. Results indicated that profiles of M. lupulina root metabolites differed from those in leaves previously detected. The roots contained fewer sugars and organic acids. Hence, compounds supporting the growth of mycorrhizal fungus (especially amino acids, specific lipids, and carbohydrates) accumulated, and their presence coincided with intensive development of AM structures. Mycorrhization determined the root metabolite profile to a greater extent than host plant development. The obtained data highlight the importance of active plant–fungi metabolic interaction at early stages of host plant development for the determination of symbiotic efficiency.

LEAFY COTYLEDONs: Connecting different stages of plant development

The life of higher plants progresses successively through embryonic, juvenile, adult, and reproductive stages. LEAFY COTYLEDON (LEC) transcription factors, first discovered in Arabidopsis thaliana several decades ago, play a key role in regulating plant embryonic development, seed maturation, and subsequent growth. Existing studies have demonstrated that LECs together with other transcription factors form a huge and complex regulatory network to regulate many aspects of plant growth and development and respond to environmental stresses. Here, we focus on the role that has received little attention about the LECs linking different developmental stages and generational cycles in plants. We summarize the current fragmented research progress on the LECs role and molecular mechanism in connecting embryonic and vegetative growth periods and the reproductive stage. Furthermore, the possibility of LECs controlling the maintenance and transition of plant growth stages through epigenetic modifications is discussed.

Fusarium species that cause corn stalk rot in the Ubaté valley of Cundinamarca, Colombia

In recent years, corn (Zea mays L.) crops in the Colombian cold tropics located in the Ubaté valley in Cundinamarca have been affected by stalk rot with incidences up to 40%. Despite the importance of this disease, accurate diagnosis has not been conducted. The objectives of the study were to determine the causal agents of corn lodging associated with stalk rot in this corn-producing region and describe the symptoms of the disease. Two plots with stalk rot reported in the municipality of Simijaca in July 2016 were sown with the regional varieties Simijaca and Sogamoso. Plants were randomly inspected on a monthly basis for describing disease symptoms and isolating the pathogen. The Fusarium species isolated were morphologically and molecularly identified and pathogenicity tests were conducted. The disease was detected at early plant developmental stages with the combination of chlorosis, leaf anthocyanosis, and dwarfism as the main symptoms in the two corn varieties evaluated. Crown and node necrosis in longitudinal sections of the stalk and purple colorations in the crown, nodes and internodes of plants were observed 90 d after sowing. Finally, lodging occurred at any phenological stage of the crop. Fusarium spp. were isolated in all stages of plant development. Fusarium species were identified as F. graminearum in the Fusarium graminearum species complex and F. subglutinans in the Fusarium fujikuroi species complex, which have cold-climate production zones as their ecological niche. Pathogenicity tests confirmed F. graminearum and F. subglutinans as the causal agents of stalk rot in the regional corn variety Simijaca in the Ubate valley in Cundinamarca.

Interactions between Halopriming and Hormopriming in Regulating the Vegetative Growth and Seed Quality of Vicia faba L.

High seed quality and growth performance is farmer’s and agricultural enterprise’s demand. However, increasing population increases food demand and due to global warming and limited natural resources, more attention has been paid to implementing different effective strategies. Halopriming and hormopriming have shown improvement in different growth and developmental stages in plants and under adverse environmental conditions. Therefore, this study was aimed to study the interaction impact of halopriming and hormopriming on growth and seed production of faba bean (Vicia faba L.). The interaction effect of seed priming was examined during germination and field growth performance of faba bean. Different salt substances NaCl (0, 25 and 50 mM) and CaSO4 (0, 2.5 and 5 mM) were used as a halopriming. Salicylic acid (SA) (0, 0.5 and 1mM) was used as a hormopriming agent. Split-plot randomize complete block design was followed with three replicates. The results show a significant increase in seed germination when the seeds were haloprimed with CaSO4 (2.5 and 5 mM) and compared with the control. NaCl (25 and 50 mM) increased the number of fruit set, brunches, pods and yield per plant significantly in comparison to the control. SA at 0.5 mM increased plant height significantly when compared with the control. These results may indicate that different varieties and species respond differently to seed priming. In addition, the interaction between the halopriming and hormopriming compounds may function as a buffer to modify the osmotic presser during imbibition, and may the seed coat of fabe bean, Aquadlge, variety prevent the transport of the compounds to the embryo. Therefore, it has been suggested and recommended to implement a combination between halopriming and hormopriming using different species and faba bean variety and study its effect at the molecular level during seed germination.

Recovery of Grain Yield and Protein with Fertilizer Application Post Nitrogen Stress in Winter Wheat (Triticum aestivum L.)

Unfavorable weather conditions and lack of appropriate farm machinery often delay N application. This results in nitrogen (N) deficiency during the vegetative and early reproductive growth stages of winter wheat. The objective of this study was to evaluate the impact of N application timings (from tillering to flag leaf growth stages) on winter wheat grain yield and protein. The study was conducted across 12 site–years in Oklahoma, US. The treatments included a non-fertilized check, a pre-plant application of 100 kg N ha−1, and ten in-season application timings at 100 kg of N ha−1. The in-season treatment applications were initiated at the point when an N deficiency was visually identified by comparing the pre-plant treatment to the non-fertilized check. The treatments were applied in a progressive order every seven growing degree days (GDD &gt; 0 °C) until a cumulative GDD of 63 was reached after visual deficiency (DAVD). All in-season treatments increased grain yield and protein as compared to the non-fertilized check, showing that N was a yield-limiting factor. The nitrogen applications made post Feekes 8 decreased grain yield when compared to pre-plant applications. Across this data set, that timing corresponded to a range of 21 to 63DAVD. The results suggested that forgoing N application until the growth stage Feekes 7, even when the visual N deficiency was highly apparent before that stage, had no negative impact on the yield, and it even increased the yield as compared to the pre-plant application in some cases. The plant developmental stage at which the N application takes place is more critical than the level of N deficiency. Our results show that N fertilizer applications should be made posteriorly to the crop dormancy to maximize both yield and protein, and that plants can recover from N deficiency when applications are made until the late-vegetative phase (Feekes 7). This document shows that winter wheat producers have a much wider N application window than traditionally believed.

A Phenological scale of statice

AbstractStatice is an important cut flower belonging to the Plumbaginaceae family and which has good acceptance among producers and consumers. The construction of a phenological scale for statice that is easy, fast, and non‐destructive can contribute to the improvement of management practices, increase flower yield and quality, increase the knowledge on the plant and facilitate the communication between the scientific and technical personnel. Field and greenhouse experiments with seven sowing dates were carried out during 2019 and 2020 at the Universidade Federal de Santa Maria, in Santa Maria, RS, Brazil, with Assorted Seeds (mix) and two cultivars (QIS Purple and QIS Yellow) of statice to describe the main stages of plant development. The developmental cycle of statice was divided into three phases: germination, vegetative and reproductive. The germination phase includes the stages S0, S1, S2 and SE, the vegetative phase comprises the stages VC, V2, V8, V10, V20, V100 and Vn, and the reproductive phase has the stages R1, R1.1, R1.2, R1.n, R2, R2.1, R2.2, R2.n, R3, R3.1, R3.2, R3.n, R4, R4.1, R4.2, R4.n, R5, R5.1, R5.2, R5.n, R6, R6.1, R6.2, R6.n, R7, R7.1, R7.2, R7.n, R8, R8.1, R8.2, R8.n and R9. Part of the vegetative development overlaps the reproductive development to represent the appearance of new leaves as new floral stems develop. The phenological scale proposed for statice has practical applications and can be easily used in the field by scientists, teachers, students, consultants and farmers.

The influence of Rhizobium tropici produced EPM biopolymer on green bush bean root and plant growth

A Rhizobium tropici (R. tropici) derived biopolymer has been reported as an effective, biodegradable, additive to reduce erosion. In addition to directly modifying the mechanical properties of the soil, it was postulated that indirectly it enhanced vegetation, which in turn stabilized the soil through enhanced root infrastructure. We therefore chose to study its impact directly on Green Bush Bean plants, where its effect could be measured in the early stages of plant development, starting from germination of the seeds through the initial growth of leaves and shoots. EPM derived from R. tropici bacteria ATCC (strain) grown in two laboratories were tested with similar results, indicating a high degree of reproducibility. Watering Bush Bean seeds with EPM concentrations as low as 50 and 100 mg/L produced a small increase of the germination rate, from 87% to 93% for seeds grown for ten days in a moist environment. The seeds were then transplanted into potting soil and allowed to grow for another three weeks, during which they were watered daily with tap water or the EPM solutions. Continued watering with EPM after transplantation showed enhancement in both root and stem/leaf mass three weeks after transplantation into potting soil by 45% for the two EPM biopolymers. Root density was also higher by 29% to 71% for EPM1.The mass of the leaf and shoots also showed a significant enhancement over the control, but in this case favoring EPM2, consistent with plants preferring either root or leaf production.

Chemical process route selection based upon potential environmental risk of chemical releases

Chemical process route selection is a key decision taken during the preliminary design stage of chemical plant development. This work presents a risk-based methodology that can be used to select the most inherently environmentally friendly chemical process route among alternate routes to produce a chemical. An index called Inherent Environmental Risk Index for Chemical Release (Chem-IERI) is proposed which represents the potential environmental risk due to a total loss of containment event in the plant. The risk index incorporates three parameters, namely the magnitude of environmental impact, the occurrence frequency of the accidental chemical release event that results in the environmental impact and the vulnerability of the environmental element where the impact is observed. Eight environmental impacts are considered and a methodology to estimate the vulnerability of environmental elements to these impacts is proposed. A higher index value indicates a higher environmental risk. The index developed was applied to assess four possible process routes to produce acetone. Propene oxidation process route showed the lowest Chem-IERI value while cumene oxidation process route showed the highest indicating the least inherent environmental friendliness.

Physico-chemical properties of maize (Zea mays L.) mucilage differ with the collection system and corresponding root type and developmental stage of the plant

PurposeMucilage plays crucial roles in root-soil interactions. Collection systems for maize (Zea mays L.) use primary and seminal roots of aeroponically-grown seedlings (CSA), or brace roots of soil-grown plants (CSB). While each method represents specific plant developmental stages, and root types growing in specific (micro-)environments, these factors are rarely considered. It is unclear whether mucilage exhibits distinct physico-chemical properties related to collection system-inherent factors.MethodsMucilage of maize genotype B73 was collected from systems CSA and CSB. Chemical composition was assessed by pH, nutrient contents, neutral sugar composition, and polysaccharide polymer length. Viscosity, surface tension and contact angle represented physical properties.ResultsThe share of hexoses among total polysaccharides was 11% higher in CSB than in CSA, whereas pentoses were predominant in CSA, together with higher nutrient concentrations and pH values. Mannose was detected only in CSB, which also exhibited higher surface tension, viscosity and contact angle compared to CSA.ConclusionsPhysico-chemical differences between the two mucilages are related to root type functions, environmental root growth conditions, and plant developmental state. Higher fractions of pentoses in CSA mucilage seem related to semi-sterile system conditions. Higher viscosity of CSB mucilage might reflect the need for enhanced water holding capacity of brace roots growing in drier conditions. A strong influence of environmental factors on mucilage properties even for a single genotype might play additional roles e.g. in the attraction of microbiomes. These aspects are relevant when assessing the role of mucilage in the rhizosphere, or when developing models of rhizosphere processes.

Behavioral Responses of Bemisia tabaci Mediterranean Cryptic Species to Three Host Plants and Their Volatiles.

Simple SummaryBemisia tabaci Gennadius (Hemiptera: Aleyrodidae) was first observed in tobacco in Greece in 1889. In China, since the introduction of Euphorbia pulcherrima (Euphorbiales: Euphorbiaceae, native to Central America) at the end of the previous century, B. tabaci has gradually become an increasingly significant agricultural pest. In recent years, the push–pull strategy has been widely applied to the control of the pest. The distinct volatiles are emitted of plants directly affect the efficiency of pushing and pulling; hence, we aimed to study the behavioral responses of B. tabaci to three plants (Gossypium hirsutum, Abutilon theophrasti, and Ricinus communis) during various growth phases (pre-flowering, fluorescence, and fruiting) and analyzed the quality and quantity of volatiles from of three growth stage, as well as identified few compounds that attract or repel the B. tabaci. The results demonstrated that the distinct volatiles are emitted by pre-flowering, flowering, and fruiting plants with varying effects on B. tabaci preference. Three volatile compounds (linalool, (Z)-3-hexenyl acetate, and nonanal) analyzed in this study had trapping/repellent effects on B. tabaci. Therefore, these compounds can be adopted as potential attractants or repellents to control B. tabaci.Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a worldwide pest that damages over 900 host plant species. The volatile organic compounds (volatiles) of contrasting plants, as well as their growth stage, influence this pest’s infestation behavior. The chemical contents of volatiles isolated from three plants (Gossypium hirsutum, Abutilon theophrasti, and Ricinus communis) during various growth phases (pre-flowering, fluorescence, and fruiting) were examined, as well as their influence on the behavior of adult B. tabaci. The olfactometer studies demonstrated that growth periods of the three plants affected the preference of B. tabaci. Volatiles of piemarker and cotton plants had dissimilar levels of attraction to adults during all stages. Volatile substances released by the castor at the stage of flowering had repellent effect on B. tabaci. In the plant versus plant combination, piemarker volatiles before and during anthesis were most preferred by adults, followed by cotton and then castor. A total of 24, 24, and 20 compounds were detected from volatiles of piemarker, cotton, and castor, respectively, and proportions among the compounds changed during different stages of plant development. The olfactory responses of B. tabaci to volatile compounds presented that linalool and high concentration of (Z)-3-hexenyl acetate had a strong trapping effect on this pest, while nonanal had a significant repellent effect at high concentration. This study indicates that distinct plants and their growth stage affect their attractiveness or repellency to B. tabaci adults, which are mediated by changing plant volatiles. These compounds obtained by analysis screening can be adopted as potential attractants or repellents to control Mediterranean (MED) B. tabaci.