Plant Root System Research Articles

Image analysis of hydroponic plant root system and 3D morphological reconstruction method

Plant roots have three-dimensional branching structure to mechanically support the above-ground portion of the plant. In addition, it is probable that each root forms an optimal morphology for the environment in which it is placed. If we can identify and analyse this three-dimensional morphology and physical properties such as rigidity and stress profile, it would be possible to propose new materials that take advantage of the branching structure. However, since it is difficult to evaluate the three-dimensional morphology of root systems in soil, we intend to capture and quantify the morphology using hydroponics. In this study, we present the results of image analysis of root morphology in 2D images we have been working on, as well as a 3D stereo imaging method and a 3D morphology reconstruction method using the direct linear transformation method (DLT).

Reinforcement Effect of Plant Root System on Collapse of Earth Canals and Levee Slopes in Ghana

Reinforcement Effect of Plant Root System on Collapse of Earth Canals and Levee Slopes in Ghana

Agricultural Use of Natural Biostimulants – Humic Substances: a Rview

This work presents the characteristics of humic substances, with particular emphasis on the properties of agricultural importance, i.e., the improvement of soil structure, soil properties and the availability of nutrients. Attention was also paid to the methods of introducing given substances into the soil and the possibility of direct application to the plant surface. The mechanisms responsible for the stimulating and protective effect of humic substances on plant development were explained in detail, including phytohormonal regulation, the mitigation of biotic and abiotic stresses, antioxidant properties and the influence on seed germination and the development of the plant root system. The economic and environmental importance of the application of the substances in question was also emphasized, consisting of maintaining the health of the soil and the quality of plants, while reducing the share of chemical fertilizers and reducing the amount of water used. It should be noted that humic substances, like any agricultural product, should be appropriately selected for the type of cultivation conducted, i.e., the optimal dose and method of application should be determined.

Knowledge and Adoption of Drip Irrigation in Citrus Crops among Farmers ofWestern Haryana

Water is becoming increasing scare which limits agricultural development not only in Indiabut also in many parts of the world. Drip irrigation is an incredibly efficient wateringmethod that slowly delivers water directly to plant root system. The present study wasundertaken to assess the knowledge and adoption level of drip irrigation in citrus cropsamong farmers of Haryana state. Majority of respondents belonged to middle age group(51.67%), general castes (96.67%), joint families (68.33%) and having land between 4-10hectares (45.00%). It was found that majority of sampled farmers (61.67%) had high levelof knowledge while 31.67 per cent had moderate level of knowledge of drip irrigation.More number of farmers had high level of adoption (40.00%) whereas 35.00 per cent hadmedium and 25.00 per cent had low level of adoption of drip irrigation. Socio-economicfactors like income, landholding, mass media exposure, education and socio-economic statusof farmers were found significantly associated with the level of knowledge and adoptionof drip irrigation. It is concluded that more efforts are required to increase the knowledgeof farmers about drip irrigation for wider adoption of micro-irrigation technologies.

FORMATION OF A SYMBIOTIC APPARATUS OF LENTIL DEPENDING ON INOCULATION AND PROCESSING OF SEEDS WITH MICROELEMENTS

The article presents the results of a long-term study of the features of the formation of the symbiotic potential of lentil plants, taking into account both the hydrothermal features of the vegetation period of plants, and from the standpoint of using various options for pre-sowing seed treatment with inoculant and complex micronutrient fertilizers. Aspects of the formation of the symbiotic potential of lentils in the context of different years according to the hydrothermal regime were determined, which made it possible to determine the optimal SCC interval for the realization of the effective potential of the formation of nodule bacteria and their vital activity. The features of the use of one of the modern lentil seed inoculants Anderiz-r and complex chelated micronutrient fertilizer for presowing seed treatment - Oracle in the format of single and combined use against the background of the recommended background of mineral nutrition at the level of 30 kg / ha of the active substance nitrogen, phosphorus and potassium from the standpoint of the formation of a symbiotic apparatus in the dynamics of the phenological development of lentils. The effect of these preparations on the formation of the number and mass of nodule bacteria on the root system of lentil plants was studied for the period from the branching of the stem to the beginning of the formation of fruit elements. It has been proven that the combined use of an inoculant and microfertilizer provides a general increase in the number of nodule bacteria on a plant by at least 80% for an increase in their mass by 2.4 times. The features of the formation of the ratio between the number and mass of nodule bacteria in lentil plants have been established both from the standpoint of hydrothermal vegetation regimes and from the standpoint of using options for pre-sowing seed inoculation and the use of complex micronutrients for the same pre-sowing seed treatment. It is noted that from the standpoint of a positive influence on the general indicators of the formation of the symbiotic potential of lentil plants, an obligatory technological element is the pre-sowing inoculation of seeds with a species-specific strain of bacteria, which makes it possible to significantly increase the total number of nodule bacteria on lentil roots from 5-7 to 30-31, depending on the phenological phase. plants and years of research

Plant Growth Promotion by Two Volatile Organic Compounds Emitted From the Fungus Cladosporium halotolerans NGPF1.

Microbial volatiles have beneficial roles in the agricultural ecological system, enhancing plant growth and inducing systemic resistance against plant pathogens without being hazardous to the environment. The interactions of plant and fungal volatiles have been extensively studied, but there is limited research specifically elucidating the effects of distinct volatile organic compounds (VOCs) on plant growth promotion. The current study was conducted to investigate the impact of VOCs from Cladosporium halotolerans NGPF1 on plant growth, and to elucidate the mechanisms for the plant growth-promoting (PGP) activity of these VOCs. The VOCs from C. halotolerans NGPF1 significantly promoted plant growth compared with the control, and this PGP activity of the VOCs was culture medium-dependent. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) identified two VOC structures with profiles that differed depending on the culture medium. The two compounds that were only produced in potato dextrose (PD) medium were identified as 2-methyl-butanal and 3-methyl-butanal, and both modulated plant growth promotion and root system development. The PGP effects of the identified synthetic compounds were analyzed individually and in blends using N. benthamiana plants. A blend of the two VOCs enhanced growth promotion and root system development compared with the individual compounds. Furthermore, real-time PCR revealed markedly increased expression of genes involved in auxin, expansin, and gibberellin biosynthesis and metabolism in plant leaves exposed to the two volatile blends, while cytokinin and ethylene expression levels were decreased or similar in comparison with the control. These findings demonstrate that naturally occurring fungal VOCs can induce plant growth promotion and provide new insights into the mechanism of PGP activity. The application of stimulatory volatiles for growth enhancement could be used in the agricultural industry to increase crop yield.

Drought stress induces changes in the physiology and root system of soybean plants

Drought stress induces changes in the physiology and root system of soybean plants

Phenotyping seedlings for selection of root system architecture in alfalfa (Medicago sativa L.)

BackgroundThe root system architecture (RSA) of alfalfa (Medicago sativa L.) affects biomass production by influencing water and nutrient uptake, including nitrogen fixation. Further, roots are important for storing carbohydrates that are needed for regrowth in spring and after each harvest. Previous selection for a greater number of branched and fibrous roots significantly increased alfalfa biomass yield. However, phenotyping root systems of mature alfalfa plant is labor-intensive, time-consuming, and subject to environmental variability and human error. High-throughput and detailed phenotyping methods are needed to accelerate the development of alfalfa germplasm with distinct RSAs adapted to specific environmental conditions and for enhancing productivity in elite germplasm. In this study methods were developed for phenotyping 14-day-old alfalfa seedlings to identify measurable root traits that are highly heritable and can differentiate plants with either a branched or a tap rooted phenotype. Plants were grown in a soil-free mixture under controlled conditions, then the root systems were imaged with a flatbed scanner and measured using WinRhizo software.ResultsThe branched root plants had a significantly greater number of tertiary roots and significantly longer tertiary roots relative to the tap rooted plants. Additionally, the branch rooted population had significantly more secondary roots > 2.5 cm relative to the tap rooted population. These two parameters distinguishing phenotypes were confirmed using two machine learning algorithms, Random Forest and Gradient Boosting Machines. Plants selected as seedlings for the branch rooted or tap rooted phenotypes were used in crossing blocks that resulted in a genetic gain of 10%, consistent with the previous selection strategy that utilized manual root scoring to phenotype 22-week-old-plants. Heritability analysis of various root architecture parameters from selected seedlings showed tertiary root length and number are highly heritable with values of 0.74 and 0.79, respectively.ConclusionsThe results show that seedling root phenotyping is a reliable tool that can be used for alfalfa germplasm selection and breeding. Phenotypic selection of RSA in seedlings reduced time for selection by 20 weeks, significantly accelerating the breeding cycle.

ПРАКТИЧЕСКИЕ АСПЕКТЫ ПРИМЕНЕНИЯ БИОУДОБРЕНИЯ «ВЕСНА» КАК ФАКТОР ЗАЩИТЫ ПОЧВЕННОГО ПЛОДОРОДИЯ

The article is devoted to the study of the effect of biofertilizers on the number of different groups of soil microarthropods of chernozem of ordinary agrocenosis of perennial grasses in the condi-tions of the Lower Don. Most groups of mites and collembolus on the agrocenosis of perennial grasses, being saprophages by the nature of nutrition, undoubtedly play an important role in the circulation of substances, indirectly affecting the productivity of the agrocenosis. It was found that when applying the biofertilizer "Vesna", the number of all groups of microarthropods at the exper-imental site exceeded the control indicators by 1.5 times. All groups of ticks showed a large num-ber, gamase and shell ticks prevailed. The number of leg-tails was less than the number of ticks in the experimental area, but it turned out to be higher than the number of leg-tails in the control ar-ea. The vertical distribution of microarthropods in the horizon of 0-20 cm of the chernozem of the ordinary agrocenosis of perennial grasses was characterized by an uneven distribution: basically all groups of ticks and longtails are concentrated in the horizon of 0-10 cm, which is determined by the gradient of hydrothermal conditions and the distribution of root systems of plants of agro-cenosis.

Antagonistic activity of endophytic actinobacteria from native potatoes (Solanum tuberosum subsp. tuberosum L.) against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum

BackgroundThe native potatoes (Solanum tuberosum subsp. tuberosum L.) grown in Chile (Chiloé) represent a new, unexplored source of endophytes to find potential biological control agents for the prevention of bacterial diseases, like blackleg and soft rot, in potato crops.ResultThe objective of this study was the selection of endophytic actinobacteria from native potatoes for antagonistic activity against Pectobacterium carotovorum subsp. carotovorum and Pectobacterium atrosepticum, and their potential to suppress tissue maceration symptoms in potato tubers. This potential was determined through the quorum quenching activity using a Chromobacterium violaceaum ATCC 12472 Wild type (WT) bioassay and its colonization behavior of the potato plant root system (S. tuberosum) by means of the Double labeling of oligonucleotide probes for fluorescence in situ hybridization (DOPE-FISH) targeting technique. The results showed that although Streptomyces sp. TP199 and Streptomyces sp. A2R31 were able to inhibit the growth of the pathogens, only the Streptomyces sp. TP199 isolate inhibited Pectobacterium sp. growth and diminished tissue maceration in tubers (p ≤ 0.05). Streptomyces sp. TP199 had metal-dependent acyl homoserine lactones (AHL) quorum quenching activity in vitro and was able to colonize the root endosphere 10 days after inoculation.ConclusionsWe concluded that native potatoes from southern Chile possess endophyte actinobacteria that are potential agents for the disease management of soft rot and blackleg.

Экологическая оценка влияния сельскохозяйственной деятельности на эмиссию углекислого газа из чернозема выщелоченного Тобол-Ишимского междуречья

Abstract. The purpose of this work is to study carbon dioxide emissions from the surface of virgin and arable chernozem during the growing season of the Tobol-Ishim interfluve. Methods. The study was conducted on virgin land, in pure steam, under grain crops and corn from May to October. The intensity of carbon dioxide release was determined by the method of Shtatnov with titration in the field. Results. Based on previous studies, based on scientifically based approaches, as well as our own experimental data, the relationship between carbon dioxide emission and hydrothermal conditions of the humus layer (0–30 cm) was investigated, and the degree of influence of the type of land and crops on the release of CO2 from the surface of leached chernozem was determined. It has been established that the chernozems of Western Siberia are characterized by very low biological activity in the spring and autumn periods. CO2 emissions in May averaged 1.0–1.6 kg/ha per hour with a coefficient of variation of 8 %. The peak release of carbon dioxide into the atmosphere occurs in June-July (2.6–6.5 kg/ha per hour). It was revealed that under grain crops the gaseous losses of C–CO2 in the summer period amount to 4.1–6.5 kg/ha per hour, and in the area of pure steam – 2.3–3.4 kg/ha. The determining role in the intensity of carbon dioxide release is played by the soil temperature (r = 0.7). During the years of research, there were no dry periods, which did not allow us to establish a reliable effect of soil moisture on CO2 emissions, the correlation coefficient was 0.2 units. Based on the results obtained, a low degree (12.8 %) of the influence of the type of land (virgin land/arable land) and crops (cereals/corn) on the intensity of carbon dioxide release into the atmosphere from the surface of chernozem was revealed. The maximum degree of influence was in hydrothermal soil conditions (65 %), on which the activity of the soil microbiota and the root system of plants depended. Scientific novelty. For the first time, the intensity of carbon dioxide release from the surface of leached chernozem was studied for the Tobol-Ishim interfluve and the degree of influence of the anthropogenic factor against the background of the hydrothermal regime of soil was established.

The Effects of Different Fertilization Practices in Combination with the Use of PGPR on the Sugar and Amino Acid Content of Asparagus officinalis

The present study examined the effects of different nitrogen (NH4NO3) and potassium (KNO3) fertilization levels in combination with a nitrogen-fixing, plant growth-promoting rhizobacteria (PGPR) inoculation on the carbohydrate (CHO), amino acid content, and nutrient concentrations (N, P, K) in the spears and the root system of asparagus plants. No significant differences were indicated between the different fertilization treatments regarding N, P, and K in the leaves and roots of asparagus. The inoculation of the asparagus fields with PGPR, no matter the type of the inorganic fertilizer, resulted in increased CHO and amino acid content of the foliage and roots of asparagus. The highest CHO content and amino acid content were recorded in the treatment that combined PGPR inoculation along with KNO3 fertilizer, indicating that higher K applications acted synergistically with the added PGPR.

Various ORSV infection symptoms on ceratorhiza induction in orchid plants

Several types of orchids that are in great demand and cultivated by various groups are Phalaenopsis sp. and Dendrobium sp. Mycorrhizae are needed by orchid plants to complete their life cycle. This is because mycorrhizae are capable of symbiosis with the root system of the host plant so that the plant's capacity to absorb elements will increase. This study aims to determine the extent to which Ceratorhiza induction on Phalaenopsis amabilis and Dendrobium discolour orchids can suppress the symptoms of Odontoglossum ringspot virus (ORSV) infection. The method used in this study was a factorial completely randomized design (CRD) with 2 factors and 4 replications. The first factor is the type of orchid used, namely Phalaenopsis amabilis (A1) and Dendrobium discolour (A2), while the second factor is the type of administration of mycorrhizae, viruses, and mycorrhizal viruses. Observation of disease symptoms is done by looking at the symptoms that appear on leaves that have been infected with ORSV. The results showed that the symptoms that appeared in Phalaenopsis amabilis were in the form of mosaic, necrosis, leaf malformation, while in Dendrobium discolour were mosaic and necrotic. Ceratorhiza was not able to suppress the symptoms of disease infection because based on the results obtained; the treatment on orchids inoculated with mycorrhizae and viruses showed more severe symptoms compared to the treatment only inoculated with viruses increased response and Dendrobium discolours showed a decreased response in leaf length, width, and number. Meanwhile, in the root organ, Dendrobium discolour showed an increased response and Phalaenopsis amabilis showed a decreased response in root length and number of roots.

Role of Auxin and Nitrate Signaling in the Development of Root System Architecture

The plant root is an important storage organ that stores indole-3-acetic acid (IAA) from the apical meristem, as well as nitrogen, which is obtained from the external environment. IAA and nitrogen act as signaling molecules that promote root growth to obtain further resources. Fluctuations in the distribution of nitrogen in the soil environment induce plants to develop a set of strategies that effectively improve nitrogen use efficiency. Auxin integrates the information regarding the nitrate status inside and outside the plant body to reasonably distribute resources and sustainably construct the plant root system. In this review, we focus on the main factors involved in the process of nitrate- and auxin-mediated regulation of root structure to better understand how the root system integrates the internal and external information and how this information is utilized to modify the root system architecture.

Unexpected diversity among small-scale sample replicates of defined plant root compartments

Community assembly processes determine patterns of species distribution and abundance which are central to the ecology of microbiomes. When studying plant root microbiome assembly, it is typical to sample at the whole plant root system scale. However, sampling at these relatively large spatial scales may hinder the observability of intermediate processes. To study the relative importance of these processes, we employed millimetre-scale sampling of the cell elongation zone of individual roots. Both the rhizosphere and rhizoplane microbiomes were examined in fibrous and taproot model systems, represented by wheat and faba bean, respectively. Like others, we found that the plant root microbiome assembly is mainly driven by plant selection. However, based on variability between replicate millimetre-scale samples and comparisons with randomized null models, we infer that either priority effects during early root colonization or variable selection among replicate plant roots also determines root microbiome assembly.

The influence of bioregulating adaptogens on the growth processes, development and decorative qualities of an orchid

At present, plant biostimulating adaptogens used in the process of growing a wide range of cultivated plants are artificial analogs of natural stimulants, the chemical composition of which contains phytohormones, amino acids and a vitamin complex, which enhance the growth and development of the root system of plants by several times. The effectiveness of these agents is explained by the creation of a mutually beneficial symbiosis of the mycelium of mycorrhizal fungi and the root system of the plant, thereby providing the roots of the orchid with biologically active elements: mineral salts, enzymes, hormones and vitamins. Mycorrhizal fungi, in turn, receive carbohydrates necessary for their growth and development. Due to the fact that indoor plants contain a small amount of growth regulators in their chemical composition, their synthetic analogs are necessary for the productive growth and development of the orchid, which determines the relevance of the research carried out. The article presents the results of experiments on the effect of biostimulating adaptogens Ribav-extra, Ecopin and Epin-extra on the process of root formation of cuttings and morphological features in the studied species of dendrobium orchid. The studied plants were propagated in three ways: by dividing the bush, pseudobulbs and cuttings. The cuttings were soaked for 18 h before planting in drug solutions at a concentration of 1 ml/10 L of water. Also, vegetative plants were sprayed twice with biostimulants: in the phase of regrowth of the first leaf and two weeks later at a concentration of 0.5 ml/10 L of water. The results obtained showed differences in the experimental variants in terms of the onset of phenological phases: the beginning of the formation and regrowth of roots, leaves and peduncles, as well as the flowering period. The reaction of dendrobium to treatment with Ribav-extra, Ecopin and Epin-extra was revealed. In plants in all variants, the preparations used stimulated the development of the root system, leaf apparatus, and the appearance of peduncles. The phenophase data in the tested plants occurred 7-28 days earlier in comparison with the control variant (without the use of bioregulators). The treatment of the test plants with the growth regulator Ribav-extra promoted earlier regrowth of the first and second roots and leaves (by 20-28 days). Ekopin turned out to be the most passive and did not significantly affect the rate of development of the tested plants. The phenophases of regrowth of the 1st root and 1st leaf began 3-5 days earlier than the plants of the control variant. Ribav-extra and Epin-extra stimulated the appearance of peduncles in plants by the age of 3 years.

New methods of cleaning soil from heavy metals

The purpose of the work was to study new methods of cleaning soil from heavy metals. In this work, it was proposed to extract heavy metals Cd, Zn, Fe, Cu, Mn, Pb from soils using the method of biological purification. For this, we recommended to carry out preliminary treatment of soils with complexones and to carry out additional introduction of biophilic elements into complex compounds. The possibility of using electromechanical treatment for removing heavy metals from soils after a preliminary increase in the mobility of ions by acidification and the use of complexation reactions is shown. The experiments were carried out on the plants of sowing oat Avena sativa L. variety Yakov when grown in laboratory conditions on sod-podzolic soil with the introduction of soluble salts of heavy metals into the soil. It was noted that the largest amount of heavy metals is concentrated in the root system of plants. When growing oats in the field, the concentration of metals in the grain was assessed: Mn - 30-35 ppm, Fe - 55-65 ppm, Cu - 4-5 ppm, Zn - 30-35 ppm, Cd, Pb < 3 ppm.

Ecological methods of protecting bearded irises in the urban environment

The article presents data from a long-term phytopathological survey of a collection of varieties Iris x hybrida Hort. Main Botanical Garden named after N.V. Tsitsin RAS (Moscow). Data on diseases of bearded irises in the urban environment were obtained, changes in the composition of the fungal complex in the rhizo- and phyllosphere were studied. Low soil fertility during the adaptation period of bearded irises worsens the formation and development of the root system of plants, increases the likelihood of increased disease damage and premature leaf fall. The experience of successful establishment of cultivators Iris x hybrida with the use of complex preventive and health-improving measures to improve fertility and reduce stress factors has been obtained. It was found that the introduction of NPK-complex, etching with a biofungicide based on phytobacteriomycin, and spraying vegetative plants with a microbiological preparation based on saprophytic antagonist fungi and bacteria within two years from the moment of transplanting varieties of garden bearded irises have a positive effect on their survival rate and decorative effect. The use of biological fungicides in combination with a complex of fertilizers is mandatory in a pesticide-free protection system for garden iris varieties sensitive to mycoses.

Germination and Agronomic Traits of Phaseolus vulgaris L. Beans Sprayed with Trichoderma Strains and Attacked by Acanthoscelides obtectus

Acanthoscelides obtectus, one of the world’s most important post-harvest pests, attacks wild and cultivated common beans (Phaseolus vulgaris L.). Four Trichoderma strains, Trichoderma arundinaceum IBT 40,837 (=Ta37), a wild-type strain producer of trichothecene harzianum A (HA); two transformed strains of Ta37, Ta37-17.139 (Δtri17) and Ta37-23.74 (Δtri23); and T. brevicompactum IBT 40,841 (=Tb41), a wild-type strain producer of the trichothecene trichodermin, were evaluated to determine the effect of these compounds on the virulence of A. obtectus and the effect of these strains on the seed’s capacity of germination and on the agronomic traits of the plants grown from these seeds. Treatments of bean seeds with different Trichoderma strains provided varying survival rates in A. obtectus adults, so life survival of insects after Tb41 strain application was reduced to 15 days. Δtri17 and Tb41 strains sprayed on P. vulgaris beans resulted in low weight losses (1.21 and 1.55%, respectively). In spite of the low germination percentage of beans treated with Δtri23 strain (lower than the germination percentages of the rest of the fungal strains applied), this treatment encouraged a greater Wet Weight of Aerial Part of the plants grown from both damaged and undamaged beans. High germination rates of Ta37 and Δtri17 strains (higher than with the rest of treatments), did not turn into a greater Wet Weight Aerial Part and Wet Weight of Root System in the future plants developed. Linear regression between the number of exit holes and the wet weight aerial part on the one hand, and between the number of exit holes and the wet weight root system on the other, showed interaction, so Δtri23 and Tb41 strains behaved differently in comparison to their respective control treatments. The number of exit holes of beans treated with Δtri23 or Tb41 was negatively correlated with both the wet weight aerial part and the wet weight root system in P. vulgaris plants. Δtri23 sprayed on undamaged beans caused the greatest Wet Weight Aerial Part and wet weight root system in plants. Due to the good results obtained by Δtri23 and Tb41 strains in this work, more studies for A. obtectus control, P. vulgaris plant growth and trichothecenes production by these strains should be explored, in order to advance in the knowledge of how these fungi could be used in the field crop, together with the application of management strategies to mitigate risks for farmers and to minimize environmental contamination.

Root System Analysis and Influence of Moisture on Soil Electrical Properties

This paper proposes a methodology for plant root system and soil moisture analysis through the geoelectrical prospecting method. Overall, bench and field experiments are implemented to analyze the behavior of electrical conductivity of the soil in relation to moisture content and plant root system growth. Specifically, Wenner array and lateral profiling technique are used to stratify the soil in horizontal layers, performing in-depth analysis. Millet (Pennisetum glaucum L.), bean (Phaseolus vulgaris L.) and sorghum (Sorghum bicolor L. Moench) are used to analyze the root system behavior. Results show that the soil water dynamics can be observed through soil stratification in horizontal layers and the plant root system is correlated with apparent electrical conductivity of the soil. Thus, geoelectric prospecting methods can be used as an analysis tool, both of soil moisture dynamics and of plant roots, to support decision making regarding soil and crop management.