Crop Root System Research Articles

Crop root system plasticity for improved yields in saline soils.

Crop yields must increase to meet the demands of a growing world population. Soil salinization is increasing due to the impacts of climate change, reducing the area of arable land for crop production. Plant root systems are plastic, and their architecture can be modulated to (1) acquire nutrients and water for growth, and (2) respond to hostile soil environments. Saline soils inhibit primary root growth and alter root system architecture (RSA) of crop plants. In this review, we explore how crop root systems respond and adapt to salinity, focusing predominately on the staple cereal crops wheat, maize, rice, and barley, that all play a major role in global food security. Cereal crops are classified as glycophytes (salt-sensitive) however salt-tolerance can differ both between species and within a species. In the past, due to the inherent difficulties associated with visualising and measuring root traits, crop breeding strategies have tended to focus on optimising shoot traits. High-resolution phenotyping techniques now make it possible to visualise and measure root traits in soil systems. A steep, deep and cheap root ideotype has been proposed for water and nitrogen capture. Changes in RSA can be an adaptive strategy to avoid saline soils whilst optimising nutrient and water acquisition. In this review we propose a new model for designing crops with a salt-tolerant root ideotype. The proposed root ideotype would exhibit root plasticity to adapt to saline soils, root anatomical changes to conserve energy and restrict sodium (Na+) uptake, and transport mechanisms to reduce the amount of Na+ transported to leaves. In the future, combining high-resolution root phenotyping with advances in crop genetics will allow us to uncover root traits in complex crop species such as wheat, that can be incorporated into crop breeding programs for yield stability in saline soils.

ЗБІЛЬШЕННЯ ЗАПАСІВ ПРОДУКТИВНОЇ ВОЛОГИ У ҐРУНТІ ЗАЛЕЖНО ВІД МІКОРИЗАЦІЇ КОРЕНЕВОЇ СИСТЕМИ РОСЛИН СІЛЬСЬКОГОСПОДАРСЬКИХ КУЛЬТУР МІКОРИЗОУТВОРЮЮЧИМИ ГРИБАМИ

Як відомо, нижні горизонти ґрунту зволожуються завдяки осіннім і зимовим опадам, а верхні – завдяки літніх, які за наявності високих температур повітря інтенсивно випаровуються. У ґрунті залишається лише 30–50% вологи від тієї кількості, яка нагромаджується в ньому завдяки опадам, а в гостро посушливі роки цей відсоток зазвичай може бути значно меншим. У зв’язку із цим однією з головних проблем у землеробстві є збереження та раціональне використання запасів продуктивної вологи. Мета досліджень – з’ясувати вплив мікоризації кореневої системи рослин сільськогосподарських культур мікоризоутворювальними грибами на формування запасу продуктивної вологи у верхньому шарі ґрунту. Польові, лабораторні та статистичні методи досліджень. За використання мікоризоутворювальних грибів отримано позитивні результати щодо їхнього впливу на формування запасу продуктивної вологи в шарі ґрунту 0–30 см. Зокрема, у посівах пшениці м’якої озимої та кукурудзи звичайної у варіантах із грибами Tuber melanosporum VITTAD (препарат Міковітал) і Trichoderma harzianum RIFAI (препарат Мікофренд) у різні терміни вегетації рослин (30, 60, 90 і 120 днів) запас продуктивної вологи в шарі ґрунту 0–30 см був на 5,3–47,8% більший, ніж у контролі. Таке зростання цього показника стало можливим завдяки збільшенню маси кореневої системи цих культур за її мікоризації, яка в рослин пшениці м’якої озимої була на 13,7–83,2%, а в рослин кукурудзи звичайної на 21,1–130,1% більшою, ніж у контролі. Накопичення більшої маси продуктивної вологи у ґрунті у варіантах із мікоризою порівняно з контролем відбувається завдяки здатності грибів створювати масу тонких абсорбуючих гіфів, які проникають у найдрібніші пори землі та збільшують таким чином поглинання поживних речовин і вологи. Мікоризоутворювальні гриби сприяють накопиченню запасів продуктивної вологи у верхньому шарі ґрунту завдяки збільшенню маси кореневої системи рослин сільськогосподарських культур і формуванню абсорбційних ниткоподібних гіфів, які проникають у найменші пори землі.

The wheat basic helix-loop-helix gene TabHLH123 positively modulates the formation of crown roots and is associated with plant height and 1000-grain weight under various conditions.

Crown roots are the main components of the fibrous root system in cereal crops and play critical roles in plant adaptation; however, the molecular mechanisms underlying their formation in wheat (Triticum aestivum) have not been fully elucidated. In this study, we identified a wheat basic helix-loop-helix (bHLH) protein, TabHLH123, that interacts with the essential regulator of crown root initiation, MORE ROOT in wheat (TaMOR). TabHLH123 is expressed highly in shoot bases and roots. Ectopic expression of TabHLH123 in rice resulted in more roots compared with the wild type. TabHLH123 regulates the expression of genes controlling crown-root development and auxin metabolism, responses, and transport. In addition, we analysed the nucleotide sequence polymorphisms of TabHLH123s in the wheat genome and identified a superior haplotype, TabHLH123-6B, that is associated with high root dry weight and 1000-grain weight, and short plant height. Our study reveals the role of TabHLH123 in controlling the formation of crown roots and provides beneficial insights for molecular marker-assisted breeding in wheat.

Bionic Design of Furrow Opener Based on Muskrat Claw-Toe Structure to Improve the Operating Performance of Deep Application of Liquid Fertilizer in Paddy Fields in Cold Region of China

The deep application of liquid fertilizer in paddy fields is a fertilization technique that applies liquid fertilizer deep near the root system of paddy field crops, which can effectively improve the absorption rate of the crops and reduce the amount of fertilizer applied. In the cold regions of China, the soil return rate of the furrowing operation of the deep application of liquid fertilizer in paddy fields is low, which can easily cause the excessive liquid leakage of fertilizer and affect crop growth. Therefore, it is difficult to popularize in large areas. According to the characteristics of paddy soil in the cold regions of China and the operating requirements of a high backfill rate and low disturbance rate of the soil of the deep application of liquid fertilizer, this paper designed a bionic liquid fertilizer deep application furrow opener based on the claw-toe structure of the muskrat. In this study, an indoor soil bin test was conducted by constructing a deep application environment for the liquid fertilizer in paddy fields. The results of the soil bin test showed the effects of the key operating parameters of the bionic design of the liquid fertilizer deep application furrow opener, spraying pressure of the liquid fertilizer and operating speed on the furrowing resistance, soil disturbance rate and the leakage amount of liquid fertilizer. The bionic design of the liquid fertilizer deep application furrow opener has a low soil disturbance rate and leakage amount of fertilizer when the operating speed is 0.8 m s−1, and the spraying pressure is 0.2 MPa. This furrow opener significantly improves the operating performance of the deep application of liquid fertilizer in the cold regions of China and is suitable for the deep application of liquid fertilizer in the paddy fields of this region.

Parameters of the furrow cutter with levellers of the combined machine

The purpose of the research is to confirm the plurals of a furrow cutter with levelers of combination machine. Combined machine turns the soil layer of the zone where the root system of field crops develops by 180°, prepares the soil for planting, and forms an irrigation ditch. The combined machine consists of disc knives, reverse-cutting ploughshare housings, roller, thresher and levellers. The conducted theoretic and pilot explore showed height combined machine sweeper should be 0.45 m, length 0.7 m, the opening angle of the wings 30°, the height of the leveller 0.1 m, the installation angle relation to the area of activity motion should be 30° showed. According to the outcome the conducted experimentation analysis, tensile strength slimmer is line of 600-650 N.

Formation of the area of the leaf surface of plants of agricultural cultures depends on the mass of the root system during its mycorization

Goal. To establish the influence of the mass of the root system during its mycorrhization on the formation of the area of leaves of agricultural crops. Methods. Field, laboratory and statistical. The results. The use of mycorrhiza-forming fungi and nitrogen-fixing bacteria for the presowing treatment of agricultural crop seeds has a significant effect on the formation of the root system, and therefore on the area of their leaf surface. In particular, the use for this purpose of such mycorrhizal fungi as Trichoderma harzianum RIFAI. and Tuber melanosporum VITTAD. (preparation Mikofrend, Mykovital) and nitrogen-fixing bacteria Bucillus subtilis Cohn. (preparation Florobacillin) helps to increase the mass of the root system of such agricultural crops as soft winter wheat, common corn, annual sunflower and cultivated soybean by 9.3–138.8%, which in turn helps to increase the leaf surface area by 2 .9–100.2% compared to the control. A particularly significant increase in this indicator was noted for the treatment of seeds of agricultural crops with the drug Micofrend, which is 100.2% compared to the control. There is a close correlation between the mass of the root system and the leaf surface area of agricultural crops, which ranges from +0.95 to +0.99%. Conclusions. Pre-sowing application of vesicular-arboscular and bacterial preparations Mycovital, Mycofriend and Florabacillin to the seeds contributes to the stable mass of the root system and leaf surface area of soft winter wheat, ordinary corn, annual sunflower and cultivated soybeans.

An improved model to simulate soil water and heat: A case study for drip-irrigated tomato grown in a greenhouse

Soil physical, chemical, and biological processes are influenced by soil water and heat conditions, which greatly depend on the crop root systems in different soil layers. Hence, understanding root distribution, soil water and heat dynamics is essential to improve water and nutrient use efficiency. A case study of tomato grown in a greenhouse with drip irrigation was conducted to test an improved two-dimensional (2D) model, namely UZflow-2D, for simulating the soil water and heat dynamics. The performance of UZflow-2D model was also compared with the well-known Hydrus-2D model. A 2D root length density (RLD) function, as a main subsidiary model of UZflow-2D, was proposed by investigating the roots distribution from lateral and radial latitudes at the four main growth stages (seedling, flowering, fruit-setting, and picking). Experimental data in 2015 was used to calibrate the parameters of UZflow-2D and Hydrus-2D models, and validated using the data of 2016. Results showed that more than 70% of the total RLD was concentrated in soil layers of 0–20 cm during the seedling, 0–40 cm during the flowering, and 0–60 cm during the fruit-setting and picking stages. The 2D RLD function perform well for locations within and between two rows, with determination coefficients higher than 0.77. Both UZflow-2D and Hydrus-2D models perform well in simulating soil water and soil temperature dynamics, while UZflow-2D model produced improved accuracy in modeling the soil water and heat dynamics within and between two rows of drip-irrigated tomato plants. The overall root mean square error (RMSE) was ∼0.008 cm3 cm−3 for soil water contents, and ∼0.434 °C for soil temperature for UZflow-2D model. However, the overall RMSE was ∼0.012 cm3 cm−3 for soil water contents, and ∼0.504 °C for soil temperature for Hydrus-2D model. Hence, the UZflow-2D model can be served as an alternatively useful tool to simulate water and heat dynamics.

Root system architecture and environmental flux analysis in mature crops using 3D root mesocosms.

Current methods of root sampling typically only obtain small or incomplete sections of root systems and do not capture their true complexity. To facilitate the visualization and analysis of full-sized plant root systems in 3-dimensions, we developed customized mesocosm growth containers. While highly scalable, the design presented here uses an internal volume of 45 ft3 (1.27 m3), suitable for large crop and bioenergy grass root systems to grow largely unconstrained. Furthermore, they allow for the excavation and preservation of 3-dimensional root system architecture (RSA), and facilitate the collection of time-resolved subterranean environmental data. Sensor arrays monitoring matric potential, temperature and CO2 levels are buried in a grid formation at various depths to assess environmental fluxes at regular intervals. Methods of 3D data visualization of fluxes were developed to allow for comparison with root system architectural traits. Following harvest, the recovered root system can be digitally reconstructed in 3D through photogrammetry, which is an inexpensive method requiring only an appropriate studio space and a digital camera. We developed a pipeline to extract features from the 3D point clouds, or from derived skeletons that include point cloud voxel number as a proxy for biomass, total root system length, volume, depth, convex hull volume and solidity as a function of depth. Ground-truthing these features with biomass measurements from manually dissected root systems showed a high correlation. We evaluated switchgrass, maize, and sorghum root systems to highlight the capability for species wide comparisons. We focused on two switchgrass ecotypes, upland (VS16) and lowland (WBC3), in identical environments to demonstrate widely different root system architectures that may be indicative of core differences in their rhizoeconomic foraging strategies. Finally, we imposed a strong physiological water stress and manipulated the growth medium to demonstrate whole root system plasticity in response to environmental stimuli. Hence, these new "3D Root Mesocosms" and accompanying computational analysis provides a new paradigm for study of mature crop systems and the environmental fluxes that shape them.

Cover crops and a devigorating rootstock can impart substantial agroecosystem services to high-resource vineyards: A multi-year study

In vineyards, cover crops typically grow concurrently with grapevines and can impart a multitude of agroecosystem services; yet concerns over potential disservices might limit adoption. Reductions in yield and vegetative growth are key disservices of concern, but at sites with high soil resources, reducing excessive vegetative growth is often considered beneficial, if the yield is not strongly penalized. To optimize agroecosystem services provided by cover crops, it is crucial to examine above- and belowground plant responses over multiple years. Documentation of the responses of fruit crop root systems to cover crops may clarify potential benefits for long-term agroecosystem services associated with aboveground growth and soil resources. In 2016, we established a perennial grass under young vines (full floor cover) to examine if agroecosystem services imparted by an under-vine cover crop change in the first five years of vineyard production and depend on rootstock vigor. Overall, cover crop reduced grapevine vegetative growth between 13% and 30% across all years and with a trend of more substantial reductions in the first two years. In contrast, yield was reduced in only three of the five years, between 9% and 25%, depending on the rootstock. Furthermore, neither cover crop nor differences in rootstock vigor resulted in relevant or consistent changes in fruit chemistry during the study. Overall, we found that in a relatively fertile, young vineyard, combining a lower vigor rootstock with a perennial, under-vine cover crop imparts substantial agroecosystem services in comparison to the more common practices of using a medium vigor rootstock and spraying herbicide under the vines. These services included improved crop load (ratio of fruit to vegetative mass), increased soil phosphorus availability, increased deep soil water content, and presumably lower labor and other costs associated with vineyard maintenance. Studies on a decadal timescale are needed to further clarify whether these services persist, accumulate with time, or if competition from the cover crop eventually leads to unacceptable decreases in vine nutrient status, growth, and production.

Design of High-Efficiency Soil-Returning Liquid Fertilizer Deep-Application Furrow Openers for Improving Furrowing Performance in Cold Regions of Northeast China

Liquid-fertilizer deep-application techniques are techniques for applying fertilizers to the root system of crops, which can effectively improve the utilization rate of fertilizers and reduce application amounts. Due to the soil viscosity of soils in the cold region of Northeast China, the soil return rate of furrow openers for liquid-fertilizer deep applications is low, which can easily cause excessive volatilizations of liquid fertilizers. Therefore, aiming at the operational requirements of low soil disturbance for liquid-fertilizer furrowing and deep applications, an efficient soil-returning liquid-fertilizer deep-application furrow opener was innovatively designed based on soil characteristics during the inter-cultivation period in the cold region of Northeast China. The discrete element method (DEM) was used to analyze the operating performance of the high-efficiency soil-returning liquid-fertilizer deep-application furrow openers, which is determined by key operating parameters including width and slip cutting angle. The DEM Virtual Simulation Experiment results show that the optimal combination is the width of 37.52 mm and a slip cutting angle of 43.27°, and the test results show that the optimal performance of the high-efficiency soil-returning liquid-fertilizer deep-application furrow opener is that the soil disturbance rate is 51.81%, and the soil-returning depth is 52.1 mm. This paper clarifies the relationship between the width and the slip cutting angle in furrowing resistance and soil disturbance and the mechanism by which the width and slip cutting angle affect soil disturbance. Above all, this study provides a theoretical and practical reference for the design of liquid-fertilizer deep-application furrow openers.

Exploitation of neighbouring subsoil for nutrient acquisition under annual-perennial strip intercropping systems

Little is known how the deep root systems of perennial crops contribute to deeper and better resource use when intercropped with annuals in arable fields. Therefore, we aimed at measuring the capacity of deep-rooted perennials, alfalfa (Medicago sativa L.) and curly dock (Rumex crispus L.) to access nutrients located under neighboring annuals at 1.0 and 2.5 m of soil depth. Alfalfa and curly dock were able to access the tracer sources (15N and Cs) placed at a distance farther than 0.4 m under the annual crop strips. As a result, the reliance on deeper soil layers for nutrient uptake by the crops grown at the borders became greater compared with the crops grown in the mid-strips. Combination of an annual cereal (winter rye) and a perennial legume (alfalfa) having contrasting root systems exhibited higher resource complementarity compared with intercroppings having more similar root systems or in the absence of legumes. Our results demonstrated that the deep-rooted perennials, when intercropped with annuals, can induce vertical niche complementarity, especially at deeper soil layers. This was assumed to be due to the differences in rooting depth and deep root activity the crop components, however, the magnitude of the effects depended on choice of crop combinations, and on types of tracers used in the study.

Application of Sophora alopecuroides organic fertilizer changes the rhizosphere microbial community structure of melon plants and increases the fruit sugar content.

Sophora alopecuroides L. is a leguminous plant commonly found in northwest China. In Xinjiang, the fresh herb of S. alopecuroides is often applied as a green fertilizer to the rhizosphere of melon (Cucumis melo) plants at the end of their flowering period, to improve the taste of the fruits. However, the effects of S. alopecuroides-based fertilizers on the microbial community structure of soil and crop-root systems are unclear. In order to study the sweetening mechanism of the S. alopecuroides organic fertilizer, three different varieties of melon were selected. The untreated plants were used as the control (CK) group, and the plants treated with S. alopecuroides-based organic fertilizer were selected as the treatment (T) group. The physical and chemical properties, enzyme activities and microbial community structure of the rhizosphere samples were also determined, and a correlation analysis with the fruit sweetness index was conducted. Sugar content of group T was at least 40% higher than that of group CK. The increase in fruit sugar content positively correlated with the increase in the abundance of beneficial microorganisms, including Pseudomonas, Bacillus, Mycobacterium, Burkholderia, Streptomyces, Acinetobacter, Proteobacteria, Lysobacter, Actinomycetes, Penicillium and Aspergillus. Sophora alopecuroides organic fertilizer could alter the composition and function of bacterial and fungal communities and promote the growth of beneficial bacteria in the melon plant rhizosphere. Further, it could increase the content of soluble solids and sugar in the fruits to achieve a sweetening effect. This fertilizer can be applied as a fruit sweetener in melon cultivation, improving the sugar content of the fruit and consequently the sweetness. © 2022 Society of Chemical Industry.

Research on an Efficient Deep-Hole Application Method for Liquid Fertilizer Based on Alternate Drilling

Liquid fertilizers are mainly applied by spraying liquid fertilizer on the surface of crop leaves and by deep openings between rows. The first causes considerable environmental pollution, and the second can easily cause to damage the root system of crops. In this study, corn crops were taken as the study object and an efficient deep-hole application method for liquid fertilizer based on alternate drilling was proposed. The needle body is driven by the spur gear wheel system in a caving mechanism to puncture holes alternately in a vertical posture and high-speed punctures are implemented with less disturbance to the soil. The cylindrical hollow cam of the mechanism is controlled so that the fertilizer needle sprays fertilizer when injected into soil and stops injecting when pulled out of the soil. Based on the bench test, fertilizer injecting performance and energy saving performance of the differential two-way fertilizer supply distribution device were analyzed and the head loss for energy saving value is 2.1, 3.1, and 5.5 m. Based on numerous field tests, the puncture track, hole width, and hole spacing are analyzed under different puncture speeds. Field tests were carried out according to a quadratic orthogonal rotating combination design and the results show that when the fertilization depth for agronomic requirements is 80 mm and the machine work speed and forward speed are 127 r min−1 and 1.40 m s−1, respectively, the hole width is 39.9 mm, the hole spacing is 320 mm. The efficient deep-hole application method for liquid fertilizer based on alternate drilling can provide support for data analysis and theoretical design of liquid fertilizer deep application technology for corn crops.

Effects of Combined Abiotic Stresses Related to Climate Change on Root Growth in Crops

Climate change is a major threat to crop productivity that negatively affects food security worldwide. Increase in global temperatures are usually accompanied by drought, flooding and changes in soil nutrients composition that dramatically reduced crop yields. Against the backdrop of climate change, human population increase and subsequent rise in food demand, finding new solutions for crop adaptation to environmental stresses is essential. The effects of single abiotic stress on crops have been widely studied, but in the field abiotic stresses tend to occur in combination rather than individually. Physiological, metabolic and molecular responses of crops to combined abiotic stresses seem to be significantly different to individual stresses. Although in recent years an increasing number of studies have addressed the effects of abiotic stress combinations, the information related to the root system response is still scarce. Roots are the underground organs that directly contact with the soil and sense many of these abiotic stresses. Understanding the effects of abiotic stress combinations in the root system would help to find new breeding tools to develop more resilient crops. This review will summarize the current knowledge regarding the effects of combined abiotic stress in the root system in crops. First, we will provide a general overview of root responses to particular abiotic stresses. Then, we will describe how these root responses are integrated when crops are challenged to the combination of different abiotic stress. We will focus on the main changes on root system architecture (RSA) and physiology influencing crop productivity and yield and convey the latest information on the key molecular, hormonal and genetic regulatory pathways underlying root responses to these combinatorial stresses. Finally, we will discuss possible directions for future research and the main challenges needed to be tackled to translate this knowledge into useful tools to enhance crop tolerance.

Spatial and Temporal Characteristics of Infiltration Wetting Front of Ring-Shaped Root Emitters

Ring-shaped root emitter is a new type of emitter applicable to the roots of fruit trees in arid areas. To study the characteristics of infiltration wetting front changes in ring-shaped root emitters, the orthogonal test method was used to design nine groups of schemes for four factors: radius of irrigation ring R, burial depth H, number of orifices M, irrigation water volume V and their three levels (R = 20, 30 and 40 cm; M = 4, 6 and 8; H = 20, 30 and 40 cm, V = 40, 60 and 80 L). The infiltration process of these nine scenarios was simulated using HYDRUS-3D software. The results show that the interference infiltration time exhibited a good power function relationship with the irrigation ring radius, number of orifices and burial depth; before the interference infiltration, the wetting fronts were all in the shape of a rotating ellipsoid centered on the infiltration point and can be expressed by the equations of the upper and lower semi-elliptic curves relative to the infiltration point. With the increase in time, the wetting fronts were centered at the infiltration point and infiltrated in all directions at a different velocity. The transport rate decreased with time. The power function relationship between the wetting fronts and the influencing factors after the interference infiltration in different directions was established, and the coefficient of determination was above 0.888. The wetting front shape after infiltration stabilization can be regarded as a rotating body formed by the vertical wetting front plane around the z-axis. The wetted soil volume of deep percolation, surface and suitable infiltration scenarios was rugby-shaped, apple-shaped with a flattened top and complete apple-shaped, respectively. Burying the irrigation ring at slightly deeper than one-third of the crop root zone is recommended, and half of the horizontal range of the crop root system can be selected as the irrigation ring radius. The research results can provide a reference for selecting root emitter parameters and layout as well as developing a root irrigation system.

Spatiotemporal Distribution of Water and Nitrogen in Border Irrigation and Its Relationship with Root Absorption Properties

The spatiotemporal distribution characteristics of water and nitrogen in the soil profile are essential influencing factors that determine the development of crop root systems. The purpose of this study was to clarify the inter-row and inter-tree variability in soil moisture in the apple root zone, and to determine the effective root diameter ranges of apple trees that influence water and nitrogen absorption. The method used was a 2-year border irrigation experiment carried out in a traditional apple orchard in Zuncun, Shanxi Province, China. Dynamic variations in the soil moisture between trees within the row (perpendicular to the direction of border irrigation) and between rows (along the direction of border irrigation) were continuously measured from 2015 to 2016, and a specific soil profile was excavated to analyze the distribution characteristics of soil water, nitrogen, and roots with different diameters. The results showed obvious variations in soil moisture in the surface soil of 0–30 cm, and the soil moisture content between rows was 5% higher than that between trees within the row. The root length density in the soil between trees within the row was 33.5% higher than that in the soil between rows. Bivariate correlation analysis showed that the correlation between the root system and nitrogen and water was ranked from highest to lowest: total nitrogen (0.741) > nitrate nitrogen (−0.36) > soil moisture (−0.273). The correlation coefficient between trees within the row was higher than that between rows. Lower soil moisture between trees within the row resulted in increased root biomass and more active uptake activity between trees within the row. There were different significant correlations between the specific root diameter and the contents of soil water and nitrogen, showing that the 1.5 mm diameter roots correlated with the water content, whereas the 2.0 mm diameter roots correlated with the nitrogen content. The findings of this study provide a deeper understanding of the absorption mechanism of crop roots for soil water and nitrogen.

Effects of Different Crop Root Systems on Soil Detachment by Concentrated Flow on the Loess Plateau in China

Soil erosion in sloping cropland is a major water and soil conservation issue in the Loess Plateau region, one of the main areas with sloping cropland in China. However, the effect of crop root systems, a major factor potentially influencing soil and water conservation in cropland, on farmland erosion, remains unclear. In the present study, soil erosion was investigated using indoor runoff scouring experiments with millet, maize, and soybean cover, with a bare surface as the control (CK), on sloping surfaces. Crop root system characteristics, rill initiation time, and erosion law, as well as their interactions, were investigated. Rill initiation time in slopes with all three crops slope were greater than that in the bare slope, indicating that crops could significantly enhance soil anti-scourability. Soil detachment rate decreased under crop cover when compared with bare land, considering the average soil detachment rate was the highest under CK, followed by under maize and soybean, and the least under millet. Slope gradient and unit discharge rate were positively correlated with soil detachment rate. Root length density, root surface area density, and root volume density were negatively correlated with soil detachment rate. Moreover, roots in the 0–1 mm diameter range dominantly influenced soil erosion.

POTENTIAL OF HORTICULTURE CROPS AND TREES IN AGROFORESTRY SYSTEMS IN INDIA

Agroforestry is a branch of science of a combined farming system of trees, crops, and animals on the same unit of land. Horticulture / tree-based agroforestry has been proven as an important tool for crop diversification. Tree and vegetable combination is new horticulture-based alley cropping system which are maintains higher output and also boosts the economic status of the farmers, improves farmers livelihood on a sustainable basis, and provide employment throughout year. The horticulture-based alley cropping systems (agroforestry) combine perennial woody crops and non-woody crops, the vegetables are managed spatially to achieve both economic and environmental benefits of the farming system. The selection of crops is depending upon various factors like agro-climatic and edaphic conditions, crop root system, and water and nutrient requirement pattern and above-ground growth habits. There are several agroforestry systems based on fruit trees is practiced in whole part of the country according to local conditions. Fruit tree-based agroforestry system has significant roles in the livelihood improvement and it provides several ways to the income generation of household and supplementary food for smallholder farmers. These systems not only provide fruits but also fulfil the timber, food, fuel, and fodder requirement. Besides, they also generate employment, provide nutritional security, reduce greenhouse gas emissions, improvement on soil health and provide sustainable economic improvement of farmers.

ТЕОРЕТИЧЕСКОЕ ОБОСНОВАНИЕ КОМПОНОВОЧНО-КОНСТРУКТИВНЫХ РЕШЕНИЙ ПОЛИВНЫХ МОДУЛЕЙ СИСТЕМ КАПЕЛЬНОГО ОРОШЕНИЯ ДРЕВЕСНО-ПЛОДОВЫХ НАСАЖДЕНИЙ

Purpose: developing the methodology for parameter determination and choosing a layout and design solution for an irrigation module for drip irrigation and fertigation of tree and fruit plants cultivated in industrial gardens using industrial technologies for agrotechnical work. The economic and production efficiency of drip-irrigated tree-fruit orchards is determined by the degree of compliance of the layout and design solutions of drip irrigation systems with the natural and climatic conditions and the needs of cultivated crops. The specified compliance of the technical capabilities of drip irrigation systems with the physiological characteristics of plants is ensured by drip irrigation modules that directly supply irrigation water or solution to the zones of their consumption by the root systems of plants. The basis of the publication was the results of the author's research and development of drip irrigation systems for industrial gardens and the author's methods for predicting the size of the contours or zones of drip moisture in the soil space and the parameters of the apple crops root systems. Results. A generalization of private author's methods for predicting the parameters of moisture contours formed in the soil column during drip irrigation, and the parameters of root systems of perennial tree-fruit crops of row planting, developed in relation to the conditions of their cultivation in drip irrigated gardens, is carried out. As a result of the adaptation and joint use of these methods, a methodology for predicting the parameters of moistening zones formed by irrigation lines located along the rows has been developed. Conclusions. A scientific and methodological justification has been developed for choosing a layout and design solution for a drip irrigation module that provides drip irrigation of tree-fruit crops of row planting cultivated in industrial drip-irrigated orchards using industrial technologies for conducting work.

Development and Validation of a Deep Learning Based Automated Minirhizotron Image Analysis Pipeline.

Root systems of crops play a significant role in agroecosystems. The root system is essential for water and nutrient uptake, plant stability, symbiosis with microbes, and a good soil structure. Minirhizotrons have shown to be effective to noninvasively investigate the root system. Root traits, like root length, can therefore be obtained throughout the crop growing season. Analyzing datasets from minirhizotrons using common manual annotation methods, with conventional software tools, is time-consuming and labor-intensive. Therefore, an objective method for high-throughput image analysis that provides data for field root phenotyping is necessary. In this study, we developed a pipeline combining state-of-the-art software tools, using deep neural networks and automated feature extraction. This pipeline consists of two major components and was applied to large root image datasets from minirhizotrons. First, a segmentation by a neural network model, trained with a small image sample, is performed. Training and segmentation are done using “RootPainter.” Then, an automated feature extraction from the segments is carried out by “RhizoVision Explorer.” To validate the results of our automated analysis pipeline, a comparison of root length between manually annotated and automatically processed data was realized with more than 36,500 images. Mainly the results show a high correlation (r = 0.9) between manually and automatically determined root lengths. With respect to the processing time, our new pipeline outperforms manual annotation by 98.1-99.6%. Our pipeline, combining state-of-the-art software tools, significantly reduces the processing time for minirhizotron images. Thus, image analysis is no longer the bottle-neck in high-throughput phenotyping approaches.