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We generalize the notion of a root system by relaxing the conditions that ensure that it is invariant under reflections and study the resulting structures, which we call generalized root systems (GRSs). Since both Kostant root systems and root systems of Lie superalgebras are examples of GRSs, studying GRSs provides a uniform axiomatic approach to studying both of them. GRSs inherit many of the properties of root systems. In particular, every GRS defines a crystallographic hyperplane arrangement. We believe that GRSs provide an intrinsic counterpart to finite Weyl groupoids and crystallographic hyperplane arrangements, extending the relationship between finite Weyl groupoids and crystallographic hyperplane arrangements established by Cuntz. An important difference between GRSs and root systems is that GRSs may lack a (large enough) Weyl group. In order to compensate for this, we introduce the notion of a virtual reflection, building on a construction of Penkov and Serganova in the context of root systems of Lie superalgebras. The most significant new feature of GRSs is that, along with subsystems, one can define quotient GRSs. Both Kostant root systems and root systems of Lie superalgebras are equivalent to quotients of root systems and all root systems are isomorphic to quotients of simply-laced root systems. We classify all rank 2 GRSs and show that they are equivalent to quotients of root systems. Finally, we discuss in detail quotients of root systems. In particular we provide all isomorphisms and equivalences among them. Our results on quotient of root systems provide a different point of view on flag manifolds, reproving results of Alekseevsky and Graev. [ABSTRACT FROM AUTHOR]

Dimitrov and Fioresi introduced an object that they call a generalized root system. This is a finite set of vectors in a Euclidean space satisfying certain compatibilities between angles and sums and differences of elements. They conjecture that every generalized root system is equivalent to one associated to a restriction of a Weyl arrangement. In this note, we prove the conjecture and provide a complete classification of generalized root systems up to equivalence. [ABSTRACT FROM AUTHOR]

The basis of orchard production is rootstocks that reduce the vigor of sweet cherry trees. However, not all rootstocks for this species can be easily propagated using traditional methods of stooling or cutting. Some of these must be propagated using the in vitro method. This is expensive and, consequently, increases the price of maiden sweet cherry trees. Our experiment assessed the growth of maiden trees of selected sweet cherry varieties ('Bellise', 'Earlise', 'Lapins', 'Vanda') depending on the method of propagation of a semi-dwarf GiSelA 5 rootstock. Additionally, the intensity of physiological processes taking place in the obtained maiden trees was also examined. The experiment compared one type of GiSelA 5 rootstock, obtained using a cheaper softwood cuttings method, with another rootstock propagated using an in vitro method. During the two years of study, there were no significant differences in the percentage of maiden trees obtained in the case of the propagation methods for both types of rootstocks, ranging from 77.43% to 87.74%. The vigor of maiden tree growth in the first year of this study was stronger than in the second year. In particular, the stem diameter of maiden trees varied from 7% to 39%, depending on the variety considered. With the exception of one variety, maiden trees produced from a rootstock propagated by stem cuttings were characterized by a larger stem diameter for the three varieties, ranging from 23% to 29%, and by a greater number of side shoots, ranging from 73% to 172%, compared to those from in vitro. Additionally, when using the stem cutting method of propagation, the rootstocks had a better developed root system, except for the 'Earlise' variety. However, most often, no significant differences were found between the methods of propagation regarding the fresh weight of the maiden trees and leaves and their leaf blade area. The activity of physiological processes of maiden sweet cherry trees varied, and no constant regularities were found. In the second year of the experiment, maiden trees were more often characterized by lower levels of net photosynthetic intensity and internal CO2 concentration, which was associated with worse growth results. Based on the collected results, it is recommended to propagate the considered rootstock using stem cuttings, which yields maiden trees with similar and sometimes even better growth parameters than those propagated using the in vitro method. [ABSTRACT FROM AUTHOR]

To increase biodiversity in tomato cultivation, two herbal aromatic plants, thyme (Thymus vulgaris) and basil (Ocimum basilicum L.), were introduced as companion plants. Their role was to improve crop plant growth and stress resistance. Moreover, the effect of the soil application of Trichoderma microbial preparations on tomato growth parameters and yield, in combination with companion plants, was studied. Ligno-cellulose multi-layer microcapsules with Trichoderma atroviride TRS14 spores (MIC14) and the commercial preparation Trianum G (TG) were used as microbial preparations. This experiment was carried out in a certified organic field. Tomato plants were intercropped with thyme or basil in the arrangement of two tomato rows alternating with one herbal row. In all intercropping arrangements and in the control (tomato plants grown without herbs), subplots were sectioned. The soil in the subplots was amended with the MIC14 and TG preparations used at a concentration of 104 spores g−1 of the soil and planted with tomato transplants. No control measures were applied during tomato growing, and the plants were naturally infected with late blight. Tomato plant growth parameters and yield were assessed, and late blight severity was monitored. The degree of soil colonization by Trichoderma fungi and the effect of these applications on soil microbial activity and biodiversity (dehydrogenases activity, EcoPlates AWCD, and Shannon index) were evaluated. The results clearly showed a significant influence of thyme and basil on tomato growth and yield in organic production. The cultivation of thyme adjacent to tomatoes had a beneficial effect on the development of the root system and the number of flowers and fruits on the crop plants. Basil, on the other hand, clearly decreased tomato yield and adversely affected the effect of Trichoderma applications by reducing root system development. Moreover, basil as a companion plant increased late blight symptoms. Both Trichoderma strains colonized soil, but they had no significant effect on the microbial activity or metabolic potential measured on the EcoPlates with the use of the BIOLOG system. However, a decrease in dehydrogenases activity was noted. In organic cultivation, the Trichoderma preparations used had no significant effect on tomato yield, opposite to its increase in integrated tomato production. [ABSTRACT FROM AUTHOR]

Background In epiphytic bromeliads, the roots were previously considered to be poorly functional organs in the processes of absorption and metabolization of water and nutrients, while the leaves were considered to always act as protagonists in both functions. More recent discoveries have been changing this old view of the root system. Scope In this review, we address previous ideas regarding the function performed by the roots of epiphytic bromeliads (mere holdfast structures with low physiological activity) and the importance of a reduced or lack of a root system for the emergence of epiphytism. We present indirect and direct evidence that contradicts this older hypothesis. Furthermore, the importance of the root absorptive function mainly for juvenile tankless epiphytic bromeliads and the characteristics of the root absorption process of adult epiphytic tank bromeliads are discussed thoroughly from a physiological perspective. Finally, some factors (species, substrate, environmental conditions) that influence the absorptive capability of the roots of epiphytic tank bromeliads are also be considered, highlighting the importance that the absorptive role of the roots has for the plasticity of bromeliads that live on trees, which is an environment characterized by intermittent availability of water and nutrients. Conclusions The roots of tank-forming epiphytic bromeliads play important roles in the absorption and metabolization of nutrients and water. The importance of roots is greatest for juvenile tankless bromeliads since the root is the main absorptive organ. In larger plants with a tank, although the leaves become the protagonists in the resource acquisition process, the roots complement the absorptive function of the leaf trichomes, resulting in improved growth of these bromeliad. The physiological and biochemical properties of the processes of absorption and distribution of resources in the tissues appear to differ between absorption by trichomes and roots. [ABSTRACT FROM AUTHOR]

Since the characteristics of plug seedlings affect the effectiveness of automatic transplanting, this study aimed to explore the effect of the addition of biochar into substrates on the growth of plug seedlings before and after transplanting. The physicochemical properties of substrates with 0%, 5%, 10%, 15%, 20%, and 25% biochar addition all met the requirements of seedling cultivation. The growth trend, root systems, and mechanical properties of seedlings before transplanting and the leaf gas exchange parameters of seedlings after transplanting were measured in this study. The results indicated that the seedlings cultivated with 10% biochar added to the substrate achieved the best growth trend and physiological indices, and the root systems under this treatment were also stronger than those of other treatments, while the seedlings cultivated with 25% biochar treatment were the worst, with less than 22.23% of the growth seen in the 10% biochar treatment, and even less than 1.5% of the growth of the seedlings cultivated without biochar treatment. Since the strong root systems could enhance the mechanical properties of seedling pots, the seedling pots cultivated with 10% biochar added into the substrate possessed the best compression resistance properties, with the maximum value of 49.52 N, and could maintain maximum completeness after free-fall impacting, wherein the loss of root and substrate was only 8.22%. The analysis results of seedlings cultivated after impacting proposed that the seedlings with better growth trends and root systems before transplanting could obtain better leaf gas exchange parameters during the flower stage after transplanting, so the seedlings cultivated with 5%~10% biochar added into the substrate grew better after impacting and then transplanting. It was noticed that the seedlings cultivated with appropriate biochar added into the substrate were able to achieve the optimal growth parameters and mechanical properties before and after transplanting, which were better able to meet the requirements of automatic transplanting. Thus, this study can promote the development of automatic transplanting technology to some extent. [ABSTRACT FROM AUTHOR]

Developing high-efficiency mixed forests or converting low-efficiency pure forests into near-natural mixed forests with optimal structure and function is a crucial aspect of forest management. In the initial stages of afforestation or stand improvement, fertilization and planting distance significantly influence the formation and development of mixed forests. This study investigated how nutrients and planting distance affect root competition between five-year-old Chinese pine (Pinus tabuliformis) and one-year-old Chinese white poplar (Populus tomentosa) and identified the factors influencing the competitive ability of these two species. Field planting experiments used three fertilization gradients (63 g·m−2, 125 g·m−2, and 250 g·m−2) of Stanley compound fertilizer with an N:P:K ratio of 2:1:1 and two planting distances (25 cm and 50 cm). Each experimental group was planted in circular plots with a radius of 0.5 m, yielding a total of nine plots. The effects of different fertilization concentrations and planting distances on root distribution were analyzed both horizontally and vertically. Pearson correlation analysis was used to assess the relationship between roots and soil nutrients, while Levins' niche overlap formula evaluated the differences in root competition between the species. Furthermore, principal component analysis quantified the relationships between impact factors and the root competitiveness of the two species. Results indicated that both species primarily allocated their fine root biomass to the shallow 0–10 cm layer. Pinus tabuliformis primarily extended to the southwest, while Populus tomentosa predominantly grew to the north. Both species exhibited enhanced root growth at moderate nutrient concentrations of 125 g·m−2. At a planting distance of 50 cm from Pinus tabuliformis, Populus tomentosa seedlings demonstrated superior root growth compared to those planted 25 cm apart. Pinus tabuliformis demonstrated greater competitive ability in the deeper 10–30 cm soil layers compared to Populus tomentosa, which showed the opposite pattern in the shallow 0–10 cm layers. Furthermore, available phosphorus (contribution rate of one impact factor on the competitiveness indexes, CR: −0.998), organic matter (CR: −0.978), total nitrogen (CR: −0.947), and alkali-hydrolysable nitrogen (CR: −0.937) significantly negatively impacted the competitiveness indexes of Pinus tabuliformis. The fine root surface area, volume, and length of Populus tomentosa also significantly negatively affected its competitiveness indexes, with all contribution rates exceeding an absolute value of 0.847. Results indicated that the root distributions of Pinus tabuliformis and Populus tomentosa overlapped spatially, with each species exhibiting advantages in different regions. Therefore, in future plantation reconstruction and forest management, it is essential to thoroughly evaluate root, soil, and fertilizer factors, adjusting planting distances accordingly, to effectively mitigate competition between the two species and successfully establish a mixed forest. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The root system plays a crucial role in water and nutrient absorption, making it a significant factor affected by nitrogen (N) availability in the soil. However, the intricate dynamics and distribution patterns of cotton (Gossypium hirsutum L.) root density and N nutrient under varying N supplies in Southern Xinjiang, China, have not been thoroughly understood. A two-year experiment (2021 and 2022) was conducted to determine the effects of five N rates (0, 150, 225, 300, and 450 kg N ha−1) on the root system, shoot growth, N uptake and distribution, and cotton yield. Compared to the N0 treatment (0 kg N ha−1), the application of N fertilizer at a rate of 300 kg N ha−1 resulted in consistent and higher seed cotton yields of 5875 kg ha−1 and 6815 kg ha−1 in 2021 and 2022, respectively. This N fertilization also led to a significant improvement in dry matter weight and N uptake by 32.4% and 53.7%, respectively. Furthermore, applying N fertilizer at a rate of 225 kg N ha−1 significantly increased root length density (RLD), root surface density (RSD), and root volume density (RVD) by 49.6–113.3%, 29.1–95.1%, and 42.2–64.4%, respectively, compared to the treatment without N fertilization (0 kg N ha−1). Notably, the roots in the 0–20 cm soil layers exhibited a stronger response to N fertilization compared to the roots distributed in the 20–40 cm soil layers. The root morphology parameters (RLD, RSD, and RVD) at specific soil depths (0–10 cm in the seedling stage, 10–25 cm in the bud stage, and 20–40 cm in the peak boll stage) were significantly associated with N uptake and seed cotton yield. Optimizing nitrogen fertilizer supply within the range of 225–300 kg N ha−1 can enhance root foraging, thereby promoting the interaction between roots and shoots and ultimately improving cotton production in arid areas. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The active development of production has a negative impact on the environment. Millions of cubic meters of forest are cut down annualy for production needs. These volumes need to be restored. Therefore, research in the field of reforestation is relevant and important. The aim of this study has been to evaluate the technology of rooting coniferous trees during summer grafting. Various terms of green cuttings of coniferous trees of the Pinaceae family were considered, common representatives in the region (Pinus sylvestris L., Picea obovata Ledeb., Picea obovata var. coerulea Malyschev, Pinus sibirica Du Tour) have been considered. The cuttings have been harvested in four terms, starting from the 3rd ten-day-period of June to the end of July. The grafting has been carried out in different conditions: in a green house with a fog plant and a climate chamber with manual watering. Several methods have been used to prepare the cuttings for planting: with and without needle removing on the lower part of the cutting. Before planting, the tested cuttings have been treated with the root formation preparation “Kornevin” (control grop – without treatment). As a result of the study, the optimal time for grafting coniferous trees for the Baikal region has been determined as the 3rd ten-day-period of June and July. The minimum rooting period for the cuttings has been figured out as 155 days. It has been noted that the cuttings whose lower part needles have not been removed, have taken root faster. Their rooting share is 10 % higher. The best rooting rate has been recorded in cuttings obtained from the plants Picea obovata Ledeb. and P. obovata var. coerulea Malyschev – 22–30%. The cuttings from Pinus sylvestris L. and P. sibirica Du Tour have a very low rooting share – less than 1 %. To determine the quality of rooting, biometric indicators of the formed roots have been obtained. The cuttings planted in the 3rd ten-day-period of June in cultivation beds with regulated fogging are characterized by powerful roots.

The growth peculiarities of Scots pine (Pinus sylvestris L.) have been studied by the example of an even-aged pine stand of high density. A long-term research has been conducted on a permanent sample plot. The data has been collected from the stand aged from 37 to 55 years. The characteristics of individual trees and the entire stand during the growth period in the absence of external influences (cutting, windfalls, pest damage, etc.) and after improvement cuttings have been analyzed. The influence of the amount of resource available to a tree on the formation of crowns, root systems and stem wood has been investigated. The size of the available resource has been the square of the dominance area. The root system of the pine trees of the studied stands is compact in size and, despite the high stand density, due to the high content of nutrients in the soil and the absence of moisture deficiency, it sufficiently ensures intensive tree growth corresponding to the conditions of the I quality class. It has been found that under these conditions, the average area of the root system is proportional to the average square of the dominance area. It has been shown that the stem diameter at a height of 1.3 m in the absence of external influences significantly depends on the square of the dominance area. The correlation coefficient of these indicators for the studied stand at the age of 37 is 0.89. The influence of cuttings on annual radial increment has been studied using dendrochronology methods. It has been revealed that in the year following the cutting, it has increased by 1.3–2.0 times, depending on the increase in the square of the dominance area. A method has been proposed for calculating the competition coefficient as a share of the resource required for the free growth of a tree, which is redistributed between its closest neighbours. Long-term observations have shown that with competition coefficients exceeding 0.6–0.7, the stem diameter increment rate decreases significantly, and the trees develop a sparse crown extending less than 40 % of the tree height. This, in turn, leads to growth retardation and a transition to a depressed state. This, in turn, leads to growth retardation and a transition to a depressed state.

Abstract The root system plays a crucial role in water and nutrient absorption, making it a significant factor affected by nitrogen (N) availability in the soil. However, the intricate dynamics and distribution patterns of cotton (Gossypium hirsutum L.) root density and N nutrient under varying N supplies in Southern Xinjiang, China, have not been thoroughly understood. A two-year experiment (2021 and 2022) was conducted to determine the effects of five N rates (0, 150, 225, 300, and 450 kg N ha−1) on the root system, shoot growth, N uptake and distribution, and cotton yield. Compared to the N0 treatment (0 kg N ha−1), the application of N fertilizer at a rate of 300 kg N ha−1 resulted in consistent and higher seed cotton yields of 5875 kg ha−1 and 6815 kg ha−1 in 2021 and 2022, respectively. This N fertilization also led to a significant improvement in dry matter weight and N uptake by 32.4% and 53.7%, respectively. Furthermore, applying N fertilizer at a rate of 225 kg N ha−1 significantly increased root length density (RLD), root surface density (RSD), and root volume density (RVD) by 49.6–113.3%, 29.1–95.1%, and 42.2–64.4%, respectively, compared to the treatment without N fertilization (0 kg N ha−1). Notably, the roots in the 0–20 cm soil layers exhibited a stronger response to N fertilization compared to the roots distributed in the 20–40 cm soil layers. The root morphology parameters (RLD, RSD, and RVD) at specific soil depths (0–10 cm in the seedling stage, 10–25 cm in the bud stage, and 20–40 cm in the peak boll stage) were significantly associated with N uptake and seed cotton yield. Optimizing nitrogen fertilizer supply within the range of 225–300 kg N ha−1 can enhance root foraging, thereby promoting the interaction between roots and shoots and ultimately improving cotton production in arid areas.

Let g be a finite-dimensional simple Lie algebra over an algebraically closed field of characteristic 0. In this paper we classify all regular decompositions of g and its irreducible root system Δ. A regular decomposition is a decomposition g = g 1 ⊕ ... ⊕ g m , where each g i and g i ⊕ g j are regular subalgebras. Such a decomposition induces a partition of the corresponding root system, i.e. Δ = Δ 1 ⊔ ... ⊔ Δ m , such that all Δ i and Δ i ⊔ Δ j are closed. Partitions of Δ with m = 2 were known before. In this paper we prove that the case m ⩾ 3 is possible only for systems of type A n and describe all such partitions in terms of m -partitions of (n + 1). These results are then extended to a classification of regular decompositions of g. [ABSTRACT FROM AUTHOR]

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Abstract Background The frequency and severity of abiotic stress events, especially drought, are increasing due to climate change. The plant root is the most important organ for water uptake and the first to be affected by water limitation. It is therefore becoming increasingly important to include root traits in studies on drought stress tolerance. However, phenotyping under field conditions remains a challenging task. In this study, plants were grown in a hydroponic system with polyethylene glycol as an osmotic stressor and in sand pots to examine the root system of eleven spring barley genotypes. The root anatomy of two genotypes with different response to drought was investigated microscopically. Results Root diameter increased significantly (p

Global climate change, which has also occurred in the Western ForestSteppe of Ukraine, has led to early sowing starting from the very beginning of the spring season. In this regard, to provide a scientific basis for spring barley cultivation technology, the issue of investigating the processes of plant growth and development before the onset of the tillering phenomenon, i.e., the second and third stages of organogenesis, is of particular relevance. The purpose of this study was to establish the regularities of dependence of spring barley plant growth and development on the influence of vegetation factors at different sowing dates in the Western Forest-Steppe of Ukraine. To summarise the findings, the following methods were employed: general scientific methods based on objectivity, evidence, reproduction, and mathematical and statistical methods for processing experimental data. The study found the dependence of the processes of growth and development of spring barley plants based on plant biomass, crude biomass, and dry matter content of the root system and aerial parts of plants, as well as leaf area according to the analysis at the beginning of the tillering phase, on the influence of sowing time. The study estimated the significance of the studied factor under the influence of supply conditions for the maximum realisation of spring barley productivity potential. As a result, a regularity was revealed, according to which a substantial decrease in the productivity potential of barley plants was established with a delay for each subsequent 10 days starting from the first sowing date on 10 March. The maximum data values were obtained at the first sowing date, where the plant biomass was 723.6 mg, the crude biomass of the root system was 67.5 mg, the dry matter of the root system was 18.0 mg, the crude biomass of the aerial part of the plant was 656.1 mg, the dry matter of the aerial part of the plant was 130.8 mg and the leaf surface area was 18.1 cm2 . As a result of the scientific substantiation, the practical value of the study lies in the favourability of early sowing dates to ensure maximum realisation of plant productivity potential due to vegetation factors

Pinus massoniana (Lamb.) safeguards China's forestry carbon sequestration value and plays a crucial role in achieving dual-carbon goals. The phenotypic information of the root system is a critical criterion for assessing the quality of robust seedlings. To address the issues of high measurement errors, low efficiency in traditional manual root measurement, and the inadequacy of existing 3D reconstruction equipment in evaluating fine root systems, a low-cost and efficient research approach for root system phenotypic information detection was designed. In this study, we outlined the root system phenotypic parameter detection methods and proposed a two-dimensional image-based data collection system. We employed suitable preprocessing methods to effectively eliminate image noise and intuitively capture the root system's skeletal features. Through conditional judgments, we pinpointed the root tip endpoints and main lateral root junctions of the root system's skeleton. The PPSA algorithm was utilized to achieve precise segmentation of main and lateral roots, and mathematical relationships were established between calibrated objects and the real environment to extract root system phenotypic parameters. The results demonstrated that the two-dimensional image-based approach for root system phenotypic information research fulfilled the rapid and efficient quality assessment requirements of nursery seedlings in forest management. [ABSTRACT FROM AUTHOR]

Background: The frequency and severity of abiotic stress events, especially drought, are increasing due to climate change. The plant root is the most important organ for water uptake and the first to be affected by water limitation. It is therefore becoming increasingly important to include root traits in studies on drought stress tolerance. However, phenotyping under field conditions remains a challenging task. In this study, plants were grown in a hydroponic system with polyethylene glycol as an osmotic stressor and in sand pots to examine the root system of eleven spring barley genotypes. The root anatomy of two genotypes with different response to drought was investigated microscopically. Results: Root diameter increased significantly (p < 0.05) under polyethylene glycol treatment by 54% but decreased significantly (p < 0.05) by 12% under drought stress in sand pots. Polyethylene glycol treatment increased root tip diameter (51%) and reduced diameter of the elongation zone (14%) compared to the control. Under drought stress, shoot mass of plants grown in sand pots showed a higher correlation (r = 0.30) with the shoot mass under field condition than polyethylene glycol treated plants (r = -0.22). Conclusion: These results indicate that barley roots take up polyethylene glycol by the root tip and polyethylene glycol prevents further water uptake. Polyethylene glycol-triggered osmotic stress is therefore unsuitable for investigating root morphology traits in barley. Root architecture of roots grown in sand pots is more comparable to roots grown under field conditions. [ABSTRACT FROM AUTHOR]

This paper is devoted to the descriptions of automorphisms and local automorphisms on complex solvable Lie algebras of maximal rank. First, it is established that any automorphism on a solvable Lie algebra of maximal rank can be represented as a product (composition) of inner, diagonal and graph automorphisms. We apply the description of automorphism to the specification of automorphisms on solvable Lie algebras of maximal rank with abelian nilradical, and to the description of automorphisms of standard Borel subalgebras of complex simple Lie algebras. Based on the representation of an automorphism, it is proved that all local automorphisms on a solvable Lie algebra of maximal rank are global automorphisms. We also present two examples of solvable Lie algebras which are not of maximal rank and have different behaviours of local automorphisms. Namely, the first algebra does not admit pure local automorphisms, while the second algebra admits a local automorphism which is not an automorphism. [ABSTRACT FROM AUTHOR]

Chari and Greenstein (Adv. Math. 220(4), 1193–1221, 2009) introduced certain combinatorial subsets of the roots of a finite-dimensional simple Lie algebra g , which were important in studying Kirillov–Reshetikhin modules over U q (g ̂) and their specializations. Later, Khare (J. Algebra. 455, 32–76, 2016) studied these subsets for large classes of highest weight g -modules (in finite type), under the name of weak- A -faces (for a subgroup A of (ℝ , +) ), and more generally, ({2};{1,2})-closed subsets. These notions extend and unify the faces of Weyl polytopes as well as the aforementioned combinatorial subsets. In this paper, we consider these "discrete" notions for an arbitrary Kac–Moody Lie algebra g , in three prominent settings: (a) the weights of an arbitrary highest weight g -module V; (b) the convex hull of the weights of V; (c) the weights of the adjoint representation. For (a) (respectively, (b)) for all highest weight g -modules V, we show that the weak- A -faces and ({2};{1,2})-closed subsets agree, and equal the sets of weights on the exposed faces (respectively, equal the exposed faces) of the convex hull of weights conv(wtV). This completes the partial progress of Khare in finite type, and is novel in infinite type. Our proofs are type-free and self-contained. For (c) involving the root system, we similarly achieve complete classifications. For the weights of ad g for any indecomposable Kac–Moody g , we show that the weak- A -faces and ({2};{1,2})-closed subsets agree, and equal the Weyl group translates of the sets of weights in certain "standard parabolic faces" (which also holds for highest weight modules). This was proved by Chari and her coauthors for Δ ⊔{0} in finite type, but is novel for other types. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective to examine the effect of management systems on root dry weight, the percentage distribution of root weight in the soil profile, and the soil carbon content. Treatments consisted of 13 management systems established 22 years ago: degraded pasture; continuous pasture, fertilised, and intercropped with a legume species; continuous pasture with fertilisation; continuous pasture without fertilisation; pasture for four years followed by soybean cropping for four years; pasture for four years followed by soybean cropping for four years, with eucalyptus; soybean cropping for four years followed by pasture for four years; soybean cropping for four years followed by pasture for four years, with eucalyptus; soybean cropping for one year followed by pasture for three years; soybean cropping for one year followed by pasture for three years; continuous summer soybean cropping under conventional cultivation; continuous summer soybean cropping under conservation farming; and continuous no-till summer soybean cropping. Except for degraded pastures, pasture systems have higher root dry mass than soybean cropping systems. The integrated production systems increase the dry weight of the roots, and the carbon content of the soil and reduce aluminum saturation and soil acidity. The highest percentages of roots are found in the 0–0.10 m range. [ABSTRACT FROM AUTHOR]

Health and quality of the root system are imperative to ensure the successful establishment of a citrus tree after transplant from the nursery into the field. Containerized citrus production in enclosed nurseries restricts root growth and can result in root circling and intertwining. This may hinder root expansion and result in root girdling after transplant, negatively affecting tree establishment and growth. The root structure of a transplanted citrus tree can also be affected by the container type used in the nursery. Containers with root-pruning properties like chemical pruning or air pruning reduce root circling and may produce superior root systems compared with regular, nonpruning containers. The aim of this study was to evaluate the effects of different nursery containers on root physiological and morphological traits and plant performance over 15 months of growth in the nursery. Three container types, chemical pruning containers, air-pruning containers, and standard nursery containers, were compared. The chemical pruning containers were standard citrus nursery containers with a mixture of copy hydroxide [Cu(OH)2] and copper carbonate (CuCO3) [10% copper (Cu)] applied to the inner wall. Pruning occurs upon contact of the roots with the Cu on the wall of the containers. The air-pruning containers were customsized Air-Pots in which pruning occurs on holes in the wall of the containers upon contact of the roots with the air. Two rootstocks, US-812 and US-942 (Citrus reticulata × Poncirus trifoliata), were included for comparison in the nongrafted stage and 12 months after grafting with 'Valencia' orange (Citrus sinensis). Chemical root pruning positively influenced tree height, shoot mass, leaf area, rootstock trunk diameter, and the nonfibrous root biomass. No differences among container types were observed for the fibrous root biomass, but chemical pruning produced more roots that were finer with a higher specific root length and a higher respiration rate. In contrast, air pruning produced more roots that were thicker compared with the other containers. Most of the leaf nutrients were lower in trees grown in the chemical pruning containers compared with the standard containers, except for Cu and zinc (Zn), which were highest in the former. Trees growing in air-pruning containers were not significantly different in growth from trees growing in standard containers. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two organic carbon resources (wood ash and sawdust) were applied in the study site to assess their profound effects on soil properties and growth and biomass properties of lupin (Lupinus albus L.). Because of their contribution to improving soil structure, enhanced water-holding capacity, and increased carbon sequestration. The experiments were conducted in mid-November 2022 at Grdarasha Research Station, College of Agricultural Engineering Sciences, Salahaddin University-Erbil, Iraq. The experiment includes two organic amendments (wood ash and sawdust) as a treatment and Control. Results showed that the application of wood ash and sawdust improved and raised the number of essential elements and heavy metals in the soil, which in turn boosted the ability of the roots to absorb nutrients. The highest germination percentage, plant height, and leaf number were observed in the ash treatment (95.00 %, 22.00 cm, and 21.22) respectively. The great values of fresh and dry shoot weight were found in sawdust treatment 63.78 and 14 g/plant) respectively. The effects of treatments were not significant on root length and fresh and dry root weights. The final findings showed that adding various forms of organic carbon could alter the chemical characteristics of the soil. This, in turn, might have a good impact on microbes, which can subsequently help plants grow by converting, solubilizing, and mobilizing soil nutrients. Furthermore, lupin plants appeared to be a form of phytoremediation, or absorption, for certain heavy metals. [ABSTRACT FROM AUTHOR]

Global climate change, which has also occurred in the Western Forest-Steppe of Ukraine, has led to early sowing starting from the very beginning of the spring season. In this regard, to provide a scientific basis for spring barley cultivation technology, the issue of investigating the processes of plant growth and development before the onset of the tillering phenomenon, i.e., the second and third stages of organogenesis, is of particular relevance. The purpose of this study was to establish the regularities of dependence of spring barley plant growth and development on the influence of vegetation factors at different sowing dates in the Western Forest-Steppe of Ukraine. To summarise the findings, the following methods were employed: general scientific methods based on objectivity, evidence, reproduction, and mathematical and statistical methods for processing experimental data. The study found the dependence of the processes of growth and development of spring barley plants based on plant biomass, crude biomass, and dry matter content of the root system and aerial parts of plants, as well as leaf area according to the analysis at the beginning of the tillering phase, on the influence of sowing time. The study estimated the significance of the studied factor under the influence of supply conditions for the maximum realisation of spring barley productivity potential. As a result, a regularity was revealed, according to which a substantial decrease in the productivity potential of barley plants was established with a delay for each subsequent 10 days starting from the first sowing date on 10 March. The maximum data values were obtained at the first sowing date, where the plant biomass was 723.6 mg, the crude biomass of the root system was 67.5 mg, the dry matter of the root system was 18.0 mg, the crude biomass of the aerial part of the plant was 656.1 mg, the dry matter of the aerial part of the plant was 130.8 mg and the leaf surface area was 18.1 cm2. As a result of the scientific substantiation, the practical value of the study lies in the favourability of early sowing dates to ensure maximum realisation of plant productivity potential due to vegetation factors. [ABSTRACT FROM AUTHOR]

Silvopastoral systems are an important strategy for sustainable livestock production. However, to expand their implementation, it is crucial to identify and develop forage materials that maintain good production and quality while being tolerant to shade conditions as well as other biotic and abiotic stresses. A field trial was conducted to evaluate the morpho-anatomical and agronomic responses of two Urochloa hybrids (Camello and Talisman) under two light conditions: shade (28 % light intensity) and full exposure. The trial followed a randomised complete block design with split-plot arrangement, where each treatment corresponded to a plot with three replications. Morphological and anatomical parameters were recorded in three technical replicates of each replication. Histological leaf sections were analysed for the percentage of adaxial epidermis, abaxial epidermis, vascular tissue, colourless parenchyma, Kranz sheath, bulliform cells, sclerenchyma, and chlorenchyma. Measurements in leaf included relative chlorophyll concentration, leaf area, leaf length, and leaf width. Evaluations in plant included height and number of tillers. Agronomic parameters such as plant cover and dry biomass were recorded for each plot. Additionally, six leaf imprints were made on the leaf undersides to observe stomatal morphology, and their length was recorded. Furthermore, plants from each treatment were grown in soil-filled tubes within the same plots. Root system photographs were taken, and in three replications per treatment, root length, root diameter, root volume, root surface area, and the depth at which 95 % of roots were concentrated (D95) were determined. These data can be utilised by the scientific community and breeders to conduct analyses and meta-analyses to identify shade tolerance mechanisms and develop genetic materials tolerant to changing climatic conditions while being optimal for use in silvopastoral systems.

Abstract The objective of this work was to evaluate whether the use of on-farm inoculants based on arbuscular mycorrhizal fungi (AMF) interferes with the agronomic performance of wheat cultivars. The following treatments were applied to cultivars TBIO Calibre and TBIO Sossego: eight on-farm inoculants, i.e., Acaulospora morrowiae, Cetraspora pellucida, Claroideoglomus etunicatum, Glomus intraradices, Rhizophagus clarus, Scutellospora heterogama, and two mycorrhizal communities from native forest (NF) obtained in the Bom Princípio (BP) and in the Flores da Cunha (FC) Brazilian municipalities; and no inoculant (control). A randomized complete block experimental design was used. Mycorrhizal colonization, root morphology, and thousand grain weight were evaluated. The association between 'TBIO Sossego' and S. heterogama provided the greatest root volume, while that between 'TBIO Calibre' and C. etunicatum and between 'TBIO Sossego' and the BP NF community resulted in the best thousand-grain weight. The use of AMF, especially C. etunicatum and S. heterogama, enhances the development of the root system of wheat. 'TBIO Calibre' showed the greatest total length and quantity of very fine roots, while 'TBIO Sossego' developed a root system with the greatest surface area and quantity of thick roots. The use of on-farm inoculants affects the agronomic performance of wheat cultivars.

Plant microbial fuel cells represent an innovative type of microbial fuel cell technology, utilizing plant rhizodeposition to fuel electrochemically active bacteria on the anode surface, thereby generating bioelectricity. This study delves into some botanical aspects of plant species employed in PMFCs and Constructed Wetland PMFCs, aiming to investigate whether their bioelectrical performance is influenced by Raunkiær life forms and root architecture. Our study involved 40 plant species described in 38 documents. In some cases, nomenclature issues prevented the interpretation of actual species used in the experiments. The bioelectrical performance of PMFCs appeared to be significantly affected by both life forms and root architecture. Therophytes and Hemicriptophytes exhibited higher median values than the other life forms, while the Geophyte group showed very high power density values despite a lower median value. In contrast, CW-PMFCs do not appeared to be significantly affected by the botanical traits considered, likely due to the limited data collected on this experimental configuration. The plant species that performed the best in PMFCs include Carex hirta, Alisma plantago-aquatica, Glyceria maxima and Canna indica, all of which have an adventitious root system. C. hirta, G. maxima and C. indica are geophytes, while A. plantago-aquatica is a hydrophyte. Consequently, epiphytes, chamaephytes and nanophanerophytes, as well as plants with fibrous root systems, appeared to be not recommended for PMFCs. Nevertheless, the results of our study may have certain limitation due to nomenclature issues that prevented the accurate identification of species used in the PMFCs, the absence of a standardized benchmark for electrical measurement, and the lack of clear match between each species and its bioelectrical performance, reducing the data pool.

[Objective] This study was aimed to explore the characteristics of soil organic carbon and moisture content under different vegetation restoration types and their relationships, and to provide a scientific basis for the selection of vegetation restoration models in the Mu Us sandy land. [Methods] Different vegetation restoration types, including natural restoration of grassland and various plants such as Artemisia desertorum, Salix psammophila, A. desertorum S. psammophila mixed (shrub-shrub mixed), Pinus sylvestris, S. psammophila P. sylvestris mixed (tree-shrub mixed), in the Mu Us sandy land, were studied. Bare sand was used as the control. The effects and correlations of different vegetation restoration types on carbon and water in the 0-5.0 m soil profile were analyzed. [Results] (1) Vegetation restoration increased, with S. psammophila P. sylvestris mixed, P. sylvestris, Grassland, A. desertorum S. psammophila mixed, A. desertorum S. psammophila mixed, and A. desertorum showing decreasing trends, with significant accumulation effects observed within the 0—0.2 m soil depth. As soil depth increased, the organic carbon content of all vegetation types gradually decreased. Within the depth range of 0.8—2.2 cm, A. desertorum, S. psammophila, and A. desertorum S. psammophila mixed exhibited carbon loss. (2) Different vegetation restoration types showed varying degrees of soil moisture deficit in deep soil layers, primarily concentrated at 1—3.0 m soil layer, with S. psammophila P. sylvestris mixed showing the most severe deficit, followed by P. sylvestris, A. desertorum S. psammophila, S. psammophila, Grassland, A. desertorum. (3) Roots were identified as the main factors influencing soil organic carbon content and moisture consumption. Soil organic carbon content exhibited a negative correlation with soil moisture within the 0—5.0 m soil depth range. [Conclusion] Vegetation carbon storage was achieved at the expense of utilizing deep soil moisture, with S. psammophila P. sylvestris mixed exhibiting the lowest water consumption per unit of fixed carbon. The study suggests that S. psammophila P. sylvestris mixed exhibits favorable effects in vegetation restoration from the perspective of soil carbon retention and water retention in the Mu Us sandy land.

[ Objective ] The study aims to analyze the metabolomic difference in potato roots under NaHCO 3 stress , in order to understand the metabolic mechanism of different potato varieties in response to NaHCO 3 stress , and to provide theoretical basis for optimizing potato breeding , cultivation techniques , and production applications. [ Methods ] The root systems of potato ‘ V 7 ’ and ‘ KANG Nibeike ’ seedlings were selected as materials , and NaHCO 3 solution was used to simulate alkali stress with different concen- trations ( CK , 10 , 20 , 30 , 40 , and 50 mmol / L ) . The root metabolites of these two potato varieties were analyzed by LC-MS and multidimensional statistics combined with non-targeted metabolomics detection. [ Results ] ( 1 ) Under NaHCO 3 stress , 160 metabolites were up-regulated and 91 metabolites were down- regulated in ‘ V 7 ’ roots , and 125 metabolites were up-regulated and 52 metabolites were down-regulated in ‘ KANG Nibeike ’ roots. ( 2 ) 10 differential metabolic pathways were selected for each of the two varieties , among which 4 differential metabolic pathways , namely biosynthesis of plant secondary metabolites , bio- synthesis of unsaturated fatty acids , synthesis of histidine and purine-derived alkaloids , and pyrimidine metabolism , were the key metabolic pathways in response to alkali stress in potato roots. ( 3 ) Differential metabolites , such as carbohydrates , amides , amines , oxy-containing organic compounds , alkaloids , phe- nolic acids , and somatogenin , etc. , were involved in the complex regulatory network in potato in response to NaHCO 3 stress. [ Conclusion ] The key metabolites and metabolic pathways of potato roots in response to NaHCO 3 stress are screened. There are differences in the metabolome of the alkaline tolerant cultivar ‘ V 7 ’ and alkali sensitive cultivar ‘ KANG Nibeike ’ . Also , there are differences between the metabolism of the same variety and CK under different levels of stress. The accumulation of amino acids and their deriva- tives , organic acids , and allantoin is an important feature of the ‘ V 7 ’ root metabolism , which is more ac- tive and alkaline resistant than ‘ KANG Nibeike ’ .

Abstract Background Soil microorganisms play an extensive role in the biogeochemical cycles providing the nutrients necessary for plant growth. Root-associated bacteria and fungi, originated from soil, are also known to influence host health. In response to environmental stresses, the plant roots exude specific molecules influencing the composition and functioning of the rhizospheric and root microbiomes. This response is host genotype-dependent and is affected by the soil microbiological and chemical properties. It is essential to unravel the influence of grapevine rootstock and scion genotypes on the composition of this microbiome, and to investigate this relationship with plant growth and adaptation to its environment. Here, the composition and the predicted functions of the microbiome of the root system were studied using metabarcoding on ten grapevine scion-rootstock combinations, in addition to plant growth and nutrition measurements. Results The rootstock genotype significantly influenced the diversity and the structure of the bacterial and fungal microbiome, as well as its predicted functioning in rhizosphere and root compartments when grafted with the same scion cultivar. Based on β-diversity analyses, 1103P rootstock showed distinct bacterial and fungal communities compared to the five others (RGM, SO4, 41B, 3309 C and Nemadex). The influence of the scion genotype was more variable depending on the community and the investigated compartment. Its contribution was primarily observed on the β-diversity measured for bacteria and fungi in both root system compartments, as well as for the arbuscular mycorrhizal fungi (AMF) in the rhizosphere. Significant correlations were established between microbial variables and the plant phenotype, as well as with the plant mineral status measured in the petioles and the roots. Conclusion These results shed light on the capacity of grapevine rootstock and scion genotypes to recruit different functional communities of microorganisms, which affect host growth and adaptation to the environment. Selecting rootstocks capable of associating with positive symbiotic microorganisms is an adaptation tool that can facilitate the move towards sustainable viticulture and help cope with environmental constraints.

Introduction: Biological nitrogen fixation (BNF) plays a crucial role in nitrogen utilization in agroecosystems. Functional characteristics of plants (grasses vs. legumes) affect BNF. However, little is still known about how ecological zones and cropping patterns affect legume nitrogen fixation. This study's objective was to assess the effects of different cropping systems on aboveground dry matter, interspecific relationships, nodulation characteristics, root conformation, soil physicochemistry, BNF, and nitrogen transfer in three ecological zones and determine the main factors affecting nitrogen derived from the atmosphere (Ndfa) and nitrogen transferred (Ntransfer). Methods: The 15N labelingmethod was applied. Oats (Avena sativa L.), forage peas (Pisum sativum L.), common vetch (Vicia sativa L.), and fava beans (Vicia faba L.) were grown in monocultures and mixtures (YS: oats and forage peas; YJ: oats and common vetch; YC: oats and fava beans) in three ecological regions (HZ: Huangshui Valley; GN: Sanjiangyuan District; MY: Qilian Mountains Basin) in a split-plot design. Results: The results showed that mixing significantly promoted legume nodulation, optimized the configuration of the root system, increased aboveground dry matter, and enhanced nitrogen fixation in different ecological regions. The percentage of nitrogen derived from the atmosphere (%Ndfa) and percentage of nitrogen transferred (%Ntransfer) of legumes grown with different legume types and in different ecological zones were significantly different, but mixed cropping significantly increased the %Ndfa of the legumes. Factors affecting Ndfa included the cropping pattern, the ecological zone (R), the root nodule number, pH, ammonium-nitrogen, nitrate-nitrogen, microbial nitrogen mass (MBN), plant nitrogen content (N%), and aboveground dry biomass. Factors affecting Ntransfer included R, temperature, altitude, root surface area, nitrogenfixing enzyme activity, organic matter, total soil nitrogen, MBN, and N%. Discussion: We concluded that mixed cropping is beneficial for BNF and that mixed cropping of legumes is a sustainable and effective forage management practice on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Phosphorus and zinc are important nutrient elements of concern in upland rice production. To determine the suitable combination of phosphorus, nanoparticles (NPs), and bio-fertilizer application as an alternative nutrient management approach in upland rice cultivation, a Polyvinyl Chloride (PVC) column experiment was conducted under controlled conditions in 2015. The treatments consisted of three phosphorus levels, two foliar sprays of NPs (ZnO and TiO2), and PSB seed treatment. The results indicated that the combined application of P (50 kg ha−1), ZnO NPs (500 ppm), and PSB seed treatment (20 g kg−1) improved the root system architecture traits of rice (total root length: 3.73–6.74%, diameter: 8.57–22.22%, and volume: 3.40–3.70%) at depths of 0–30 cm and 30–60 cm, compared to higher P + TiO2 NPs + no PSB. Consequently, this combination led to an enhancement in photosynthetic leaf area (by 3.3%), tiller numbers (by 7%), and dry matter production (by 35.5%). The favorable root growth resulting from the application of higher P and PSB enhanced zinc uptake by rice grains (by 38.44%) and straw (by 26.99%). Furthermore, the supplemental application of PSB improved the activity of soil enzymes such as dehydrogenase and phosphatase. As a result, maximum phosphorus use efficiency (PUE; 31.5%) was achieved through the combined application of P (50 kg ha−1) × ZnO NPs × PSB. In conclusion, this study demonstrated the beneficial effects of an integrated approach involving phosphorus, PSB, and metal oxides (ZnO NPs) as a fertilizer management strategy to enhance the total biomass and PUE of upland rice. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider the operations of projection and lifting of Weyl chambers to and from a root subsystems of a finite roots system. Extending these operations to labeled galleries, we produce pairs of such galleries that satisfy some common wall crossing properties. These pairs give rise to certain morphisms in the category of Bott-Samelson varieties earlier considered by the author. We prove here that all these morphisms define embeddings of Bott-Samelson varieties (considered in the original interpretation based on compact Lie groups due to Raoul Bott and Hans Samelson) skew invariant with respect to the compact torus. We prove that those embeddings that come from projection and lifting preserve two natural orders on the set of the points fixed by the compact torus. We also consider the application of these embeddings to equivariant cohomology. The operations of projection and lifting can also be applied separately to each segment of a gallery. We describe conditions that allow us to glue together the galleries obtained this way. [ABSTRACT FROM AUTHOR]

Plants' root properties are closely related to their ecological adaptability. This study aimed to clarify the differences in root properties of Stipa krylovii under different grazing disturbances. The morphological characteristics of root length, root surface area, root volume, root tip number, specific root length, and specific surface area of S. krylovii were compared under no grazing, light grazing, moderate grazing and heavy grazing conditions. The ecological adaptability to grazing pressure was also examined. Results showed that the underground biomass density decreased with the increase in grazing intensity. Grazing disturbance can lead to changes in plant community characteristics, and roots adapt to changes in these environmental factors by adjusting their distribution. Among the six root configuration parameters, those under light grazing were significantly higher than those under the other grazing types. The root length and root surface area were concentrated in the range of 0–2 mm. Mild grazing and moderate grazing were conducive to fine root penetration and contact with soil. Moderate grazing disturbance was beneficial to grassland vegetation productivity and played an important role in the stability and sustainable utilization of grassland ecosystem. [ABSTRACT FROM AUTHOR]

The article is devoted to the growth and development of the corn root system at various norms of mineral fertilizers and biostimulants in the gray soils of Uzbekistan. The introduction of mineral fertilizers and biostimulants "VL-77" and "Avangard Start" have a positive effect on the formation of the root system and the distribution of the root system in the arable and subsurface layers of the soil. It was revealed that when applying fertilizers in the norms N180P120K90 and N250P175K125 kg/ha and the use of biostimulants, it stimulates the weight of the root system and above-ground organs. It has been established that when applying fertilizers in the norm N250P175K125 kg/ha and the biostimulator "VL-77", the corn root system is located more in the arable soil layer. This contributes to a more efficient use of nutrients, and thus creates favorable conditions for the formation of a high yield of corn. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) is one of the most important cereal crops worldwide, and its production is challenged by global climate change and a shortage of resources. The root system plays a vital role in uptaking water and nutrients and sensing soil environmental signals, and it has great potential to improve the final yield and stress tolerance of wheat. In order to further explore the genes regulating root development, this study focused on qRS-6D, located on chromosome 6D and spanning from 462,701,391 to 465,068,943, which was significantly associated with the total root length, root volume, root surface, and root fresh weight in our previous GWAS analysis. Firstly, its genetic effects were validated using an F6 segregating population by comparing the root-related traits of homologous lines harboring the alternative haplotypes of this QTL. Then, the number of causal genes of this QTL was narrowed down to four with a transcriptome-wide association study. Additionally, qRS-6D has been demonstrated to have genetic effects on several yield- (kernel length, kernel width, and thousand-kernel weight) and plant structure-related traits (plant height, peduncle length, total tiller number, productive tiller number, flag leaf length, and flag leaf angle). Relatively, the frequency of the favorable haplotype increased with the wheat breeding practice. This study provides a reliable genetic locus to improve root development and structure and evaluate its application potential in wheat breeding improvement. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Soil microorganisms play an extensive role in the biogeochemical cycles providing the nutrients necessary for plant growth. Root-associated bacteria and fungi, originated from soil, are also known to influence host health. In response to environmental stresses, the plant roots exude specific molecules influencing the composition and functioning of the rhizospheric and root microbiomes. This response is host genotype-dependent and is affected by the soil microbiological and chemical properties. It is essential to unravel the influence of grapevine rootstock and scion genotypes on the composition of this microbiome, and to investigate this relationship with plant growth and adaptation to its environment. Here, the composition and the predicted functions of the microbiome of the root system were studied using metabarcoding on ten grapevine scion-rootstock combinations, in addition to plant growth and nutrition measurements. Results: The rootstock genotype significantly influenced the diversity and the structure of the bacterial and fungal microbiome, as well as its predicted functioning in rhizosphere and root compartments when grafted with the same scion cultivar. Based on β-diversity analyses, 1103P rootstock showed distinct bacterial and fungal communities compared to the five others (RGM, SO4, 41B, 3309 C and Nemadex). The influence of the scion genotype was more variable depending on the community and the investigated compartment. Its contribution was primarily observed on the β-diversity measured for bacteria and fungi in both root system compartments, as well as for the arbuscular mycorrhizal fungi (AMF) in the rhizosphere. Significant correlations were established between microbial variables and the plant phenotype, as well as with the plant mineral status measured in the petioles and the roots. Conclusion: These results shed light on the capacity of grapevine rootstock and scion genotypes to recruit different functional communities of microorganisms, which affect host growth and adaptation to the environment. Selecting rootstocks capable of associating with positive symbiotic microorganisms is an adaptation tool that can facilitate the move towards sustainable viticulture and help cope with environmental constraints. [ABSTRACT FROM AUTHOR]

Drought is the most important factor limiting winter wheat yield in the North China Plain (NCP). Choosing high-yielding cultivars is an important measure to minimize the negative effects of drought stress. Field studies were conducted with 10 cultivars in the 2020–2022 seasons under three irrigation treatments (I0, without irrigation; I1, irrigated at jointing stage; I2, irrigated at jointing and anthesis stages) in the NCP to examine the water use strategies and root and shoot traits of high-yielding cultivars under different water supply conditions. The results showed that yield variation among cultivars was 21.2–24.6%, 23.7–25.9% and 11.6–15.3% for the I0, I1 and I2 treatments, respectively. Under water deficit conditions (I0 and I1), high-yielding cultivars reduced water use during vegetative stages and increased soil water use during reproductive stages, especially water use from deeper soil layers. Those cultivars with higher root length density (RLD) in deep soil layers exhibited higher water uptake. Each additional millimeter of water used after anthesis from the 100–200 cm soil layers increased grain yield by 23.6–29.6 kg/ha and 16.4–28.5 kg/ha under I0 and I1, respectively. This water use strategy enhanced dry matter accumulation after anthesis, decreased canopy temperature (CT) and increased relative leaf water contents (RLWC), which ultimately improved grain yield. For winter wheat grown under I2, cultivars that decreased water use after anthesis had higher water productivity (WP). Root length (RL), root weight (RW) and root:shoot ratio were each negatively correlated with grain yield, while above-ground biomass was positively correlated with grain yield. Therefore, higher dry matter accumulation and smaller root systems are two important traits of high-yielding cultivars under sufficient water supply conditions (I2) in the NCP. [ABSTRACT FROM AUTHOR]

The response of preferential flow to the soil − root − rock fragment systems is essential for understanding the eco-hydrological processes in karst rocky desertification (KRD) areas. In this study, we investigated the soil properties, root, and rock fragment distribution characteristics and preferential flow in this system. Results show that there are differences in the development of preferential flow under five grades of rocky desertification: light rocky desertification (LRD) > potential rocky desertification (PRD) > non-rocky desertification (NRD) > moderate rocky desertification (MRD) > severe rocky desertification (SRD). Different degrees of rocky desertification have facilitating or inhibiting effects on preferential flow. LRD and PRD promote preferential flow with ratio of 6.6 %–9.6 %, while MRD and SRD inhibit preferential flow with ratio of 4.2 %–6.7 %. The preferential flow is simultaneously influenced by the components of soil − root − rock fragment systems. Root system indicators (i.e., root biomass, root bulk density, and root length density) generally decrease as grades of rocky desertification increase. The surface outcrops density, rock fragment density, and volume fraction tend to increase with grades of rocky desertification. A principal components analysis found that preferential flow of MRD and SRD is highly influenced by rock fragments, while LRD is more driven by root systems and soil properties. PRD is averagely influenced by the combination. These findings suggest that appropriate plant and rock fragment ratios can effectively avoid water loss in the form of preferential flow and more attention should be paid to the ecological problems of LRD and PRD areas.

Health and quality of the root system are imperative to ensure the successful establishment of a citrus tree after transplant from the nursery into the field. Containerized citrus production in enclosed nurseries restricts root growth and can result in root circling and intertwining. This may hinder root expansion and result in root girdling after transplant, negatively affecting tree establishment and growth. The root structure of a transplanted citrus tree can also be affected by the container type used in the nursery. Containers with root-pruning properties like chemical pruning or air pruning reduce root circling and may produce superior root systems compared with regular, nonpruning containers. The aim of this study was to evaluate the effects of different nursery containers on root physiological and morphological traits and plant performance over 15 months of growth in the nursery. Three container types, chemical pruning containers, air-pruning containers, and standard nursery containers, were compared. The chemical pruning containers were standard citrus nursery containers with a mixture of copy hydroxide [Cu(OH)2] and copper carbonate (CuCO3) [10% copper (Cu)] applied to the inner wall. Pruning occurs upon contact of the roots with the Cu on the wall of the containers. The air-pruning containers were custom-sized Air-Pots in which pruning occurs on holes in the wall of the containers upon contact of the roots with the air. Two rootstocks, US-812 and US-942 (Citrus reticulata × Poncirus trifoliata), were included for comparison in the nongrafted stage and 12 months after grafting with ‘Valencia’ orange (Citrus sinensis). Chemical root pruning positively influenced tree height, shoot mass, leaf area, rootstock trunk diameter, and the nonfibrous root biomass. No differences among container types were observed for the fibrous root biomass, but chemical pruning produced more roots that were finer with a higher specific root length and a higher respiration rate. In contrast, air pruning produced more roots that were thicker compared with the other containers. Most of the leaf nutrients were lower in trees grown in the chemical pruning containers compared with the standard containers, except for Cu and zinc (Zn), which were highest in the former. Trees growing in air-pruning containers were not significantly different in growth from trees growing in standard containers.