Grain Yield Of Crop Research Articles

The use of bird droppings, mineral and organomineral fertilizers in solving the issue of increasing productivity of agricultural lands of the Trans-Urals

Studies conducted to study the effect of the use of combinations of bird droppings and mineral fertilizers, organic fertilizers on the yield of grain crops in a crop rotation showed that this technique can significantly increase the productivity of arable land. On average, over three years of research, the increase in the use of mineral fertilizers and bird droppings was 45.3–46.6 % higher than in the variant without fertilizers. The use of organic mineral fertilizers obtained on the basis of bird droppings with mineral enrichment highly effective intake, grain productivity of spring wheat and oats even in adverse weather conditions exceeded the control options by 44–47 %. Conducted comparative analysis of the options with mineral fertilizers and organomineral fertilizers showed that the latter are not inferior in direct effect, and in some cases even superior to the mineral counterpart. Comparative production tests have confirmed the significant economic efficiency of using complex organomineral fertilizers compared to its industrial mineral counterpart.

Comparative evaluation of seeding spring wheat methods when using different types of coulters

The studies were carried out with the aim of identifying the most effective method for sowing spring wheat for the Pre-Baikal region through a comparative study of sowing machines of domestic and foreign production with different types of openers according to the backgrounds of dump, non-dump and zero tillage. The research was carried out on the basis of advanced farms in the Irkutsk region, widely using modern sowing units in 2016-2018 on typical gray forest loamy soils. In experiments, in comparison with the SZ-3,6 seeder, the Case IH Concord 2000, John Deere 1830, Morris Concept 2000, Tom-10 sowing complexes were studied, providing strip-spread, tape, single-line sowing with paw, anchor and disk coulters. As a result, it was found that the application of the band-spread method of sowing with the Concord 2000, John Deere 1830, Morris Concept 2000 sowing complexes increases the field germination of spring wheat seeds by 10-20%, plant standing density by 34-42%, and yield by 0.38- 0.47 t/ha. An increase in the depth of seed placement to 5-6 cm led to an increase in the yield of wheat by 0.16 t/ha when sowing SZ-3.6; 0.26 t/ha when sowing John Deere 1830; 0.23 t/ha when sowing Concord 2000. In the pre-Baikal agricultural sector, to increase the yield of grain crops, it is advisable instead of the ordinary method of sowing with the SZ-3.6 seeders to apply the tape and strip-spread methods of sowing with the paw and anchor coulters both for dump and for subsurface processing and for direct sowing. The most promising sowing machines are the sowing complexes Concord 2000, John Deere 1830, Morris Concept 2000 and their domestic counterparts Kuzbass-8.5.

НАПРАВЛЕНИЯ И ФОРМЫ АДАПТАЦИИ ОПЫТА СЕЛЬСКОХОЗЯЙСТВЕННОГО ПРОИЗВОДСТВА К ИНТЕГРАЦИИ В ЦИФРОВЫЕ ПЛАТФОРМЫ ФУНКЦИОНИРОВАНИЯ АПК

The article discusses the main directions and forms of adaptation of agricultural production experience to integration into digital platforms for the functioning of the agricultural sector. The informational and statistical basis of the study is determined; a circle of modern research centers that deal with the use of digital technologies in the agricultural sector is outlined; the technologies used in the agricultural sector are classified based on the cliometric approach, that demonstrated by analyzing the yield of grain crops in Russia from 1850 to 2019. Digital platforms for the functioning of the agro-industrial complex are highlighted, allowing to implement areas and forms of adaptation of agricultural production experience to integration into them. Concrete recommendations are given on the use of digital technologies in the field of agricultural production from the standpoint of increasing the competitiveness of agro-food products.

Sensor-Cloud based Precision Agriculture Approach for Intelligent Water Management

Water deficits reduce plant growth. Moisture stress affects the development of plant organs, which in turn can have very profound effects on plant growth. Initiation and differentiation of vegetative and reproductive organs, as well as cell division and cell enlargement, are very sensitive to water stress. The size of the vegetative organs in part determines the yield of grain crops, and therefore the yield is often determined before heading or flowering. Factors that determine the size of plant vegetative organs are many, and they are interrelated in a complex manner. Environmental factors rank high among those that determine vegetative growth, and among these environmental factors, nitrogen, soil temperature, and soil water play key roles. In this paper, we present a sensor-cloud based precision agriculture for intelligent water management for effective productivity in agriculture.

Reconstruction of grain yield in the steppe zone of the Altai territory (south of Western Siberia) in the XIX-XX centuries on the basis of tree-ring chronologies of tape burs

The article presents the results of the reconstruction of the yield of grain crops of the economy of the Volchikhinsky district of the Altai Territory (south of Western Siberia) on the basis of an extended tree-ring chronology until 1822. Based on the restored series, the cyclical nature of cereal productivity was analyzed. In particular, the 22-, 25-, and 27-year cycles are highlighted as the most significant. The increase in the amplitude of variability of the yield series was noted by year from the middle of the 19th century to the end of the 20th century.

CONCENTRATION OF NITRATE NITROGEN IN THE SOIL AND PRODUCTIVITY OF CROPS WHEN LONG-TERM MINIMIZING OF TILLAGE ACCORDING TO VARIOUS FORECROPS

In a multifactor stationary field experiment on the area of the Elitnoye Holding in the Novosibirsk region (central forest-steppe subzone) in 2002-2018 the seasonal dynamics of nitrate nitrogen in the fields of four full grain-steam crop rotation by steam and grain predecessors against an extensive background (without chemical means) in four versions of the main mechanical treatment of leached black soil was investigated. Along with this, the productivity of grain crops was studied with long-term minimization of the main tillage on extensive and intensive backgrounds. The authors found out that in the central forest-steppe of the Ob river region before sowing grain crops according to the various methods of steam preparation most of all in the meter layer of nitrate soil was found in black steam with plowing (150 kg / ha) and less in variants with soil-protective treatments (132-141 kg / ha ). The lowest level of this element in the soil (124 kg / ha) in spring was noted by the early minimum steam. Before sowing the second wheat after steam, the nitrate nitrogen content in the meter soil layer for plowing (79 kg / ha) was slightly higher than in the options with soil treatment (61-64 kg / ha). In the final field of crop rotation, regardless of the studied soil cultivation systems, the minimum initial amount of nitrogen (56-57 kg / ha) was noted. By the end of the growing season of crops, the nitrate content in the soil was sharply reduced. Before harvesting wheat by steam, the nitrogen content in the upper meter profile was 41-55 kg / ha, for grain precursors even less - 27-33 kg / ha. The steam yield of grain crops on extensive and intensive backgrounds was 3.09-3.21 and 3.96-4.02 t / ha, respectively, and practically did not depend on the methods of its preparation. On repeated sowing the wheat yield in comparison with an extensive background in plowing (1.26-1.79 t / ha) was significantly higher than in the studied options for minimizing the main tillage (1.02-1.55 t / ha). When optimizing the mineral nutrition of plants and the phytosanitary situation of crops, wheat productivity by grain predecessors in crop rotation fields increased 2.0-2.9 times without significant differences in soil treatment options.

Capturing Maize Stand Heterogeneity Across Yield-Stability Zones Using Unmanned Aerial Vehicles (UAV).

Despite the new equipment capabilities, uneven crop stands are still common occurrences in crop fields, mainly due to spatial heterogeneity in soil conditions, seedling mortality due to herbivore predation and disease, or human error. Non-uniform plant stands may reduce grain yield in crops like maize. Thus, detecting signs of variability in crop stand density early in the season provides critical information for management decisions and crop yield forecasts. Processing techniques applied on images captured by unmanned aerial vehicles (UAVs) has been used successfully to identify crop rows and estimate stand density and, most recently, to estimate plant-to-plant interval distance. Here, we further test and apply an image processing algorithm on UAV images collected from yield-stability zones in a commercial crop field. Our objective was to implement the algorithm to compare variation of plant-spacing intervals to test whether yield differences within these zones are related to differences in crop stand characteristics. Our analysis indicates that the algorithm can be reliably used to estimate plant counts (precision >95% and recall >97%) and plant distance interval (R2 ~0.9 and relative error <10%). Analysis of the collected data indicated that plant spacing variability differences were small among plots with large yield differences, suggesting that it was not a major cause of yield variability across zones with distinct yield history. This analysis provides an example of how plant-detection algorithms can be applied to improve the understanding of patterns of spatial and temporal yield variability.

Model, algorithm and computer application for automated selection of varieties and hybrids of grain crops

Under the conditions of modern high-tech agricultural production, there is a need to develop tools contributing to the scientifically based selection of adaptive varieties and hybrids, considering agrotechnological and soil-climatic features specific for each individual agricultural system. Their development and further implementation in agriculture will contribute to stable and profitable yields of grain crops. Solving this problem, issues related to the definition of criteria that accurately describe the characteristics of the conditions and the degree of their impact on cultivated varieties and hybrids of grain crops are of great importance. The process of cultivar changing due to the changes of climatic, environmental, economic and other conditions is quite common in agriculture and therefore, there is an obvious need of agricultural producers for development of such software. As a result of the research work, a concise mathematical model, an algorithm, a database structure and software were developed to enable obtaining a list of most appropriate varieties/hybrids of main grain crops for the conditions of the European part of the Russian Federation on the basis of user-defined parameters (depending on the selected grain crop). The software was designed in the form of a Web-application accessible from any device connected to the Internet, and the program interfaces were fitted for personal computers, tablet devices and smartphones. The application allows flexible configuration to add new crops, varieties (hybrids) and parameters without changing the source code of the program modules.

High throughput procedure utilising chlorophyll fluorescence imaging to phenotype dynamic photosynthesis and photoprotection in leaves under controlled gaseous conditions

BackgroundAs yields of major crops such as wheat (T. aestivum) have begun to plateau in recent years, there is growing pressure to efficiently phenotype large populations for traits associated with genetic advancement in yield. Photosynthesis encompasses a range of steady state and dynamic traits that are key targets for raising Radiation Use Efficiency (RUE), biomass production and grain yield in crops. Traditional methodologies to assess the full range of responses of photosynthesis, such a leaf gas exchange, are slow and limited to one leaf (or part of a leaf) per instrument. Due to constraints imposed by time, equipment and plant size, photosynthetic data is often collected at one or two phenological stages and in response to limited environmental conditions.ResultsHere we describe a high throughput procedure utilising chlorophyll fluorescence imaging to phenotype dynamic photosynthesis and photoprotection in excised leaves under controlled gaseous conditions. When measured throughout the day, no significant differences (P > 0.081) were observed between the responses of excised and intact leaves. Using excised leaves, the response of three cultivars of T. aestivum to a user—defined dynamic lighting regime was examined. Cultivar specific differences were observed for maximum PSII efficiency (Fv′/Fm′—P < 0.01) and PSII operating efficiency (Fq′/Fm′—P = 0.04) under both low and high light. In addition, the rate of induction and relaxation of non-photochemical quenching (NPQ) was also cultivar specific. A specialised imaging chamber was designed and built in-house to maintain gaseous conditions around excised leaf sections. The purpose of this is to manipulate electron sinks such as photorespiration. The stability of carbon dioxide (CO2) and oxygen (O2) was monitored inside the chambers and found to be within ± 4.5% and ± 1% of the mean respectively. To test the chamber, T. aestivum ‘Pavon76’ leaf sections were measured under at 20 and 200 mmol mol−1 O2 and ambient [CO2] during a light response curve. The Fv′/Fm′was significantly higher (P < 0.05) under low [O2] for the majority of light intensities while values of NPQ and the proportion of open PSII reaction centers (qP) were significantly lower under > 130 μmol m−2 s−1 photosynthetic photon flux density (PPFD).ConclusionsHere we demonstrate the development of a high-throughput (> 500 samples day−1) method for phenotyping photosynthetic and photo-protective parameters in a dynamic light environment. The technique exploits chlorophyll fluorescence imaging in a specifically designed chamber, enabling controlled gaseous environment around leaf sections. In addition, we have demonstrated that leaf sections do not different from intact plant material even > 3 h after sampling, thus enabling transportation of material of interest from the field to this laboratory based platform. The methodologies described here allow rapid, custom screening of field material for variation in photosynthetic processes.

On the efficiency of natural agro-potentsial use in the steppe regions of European Russia

Main aspects of optimizing the use of natural agro-potential of the steppe zone of European Russia are considered taking into account the available natural and socio-economic resources. The study was carried out by comparing the actual and biopotential yield of grain crops as key agricultural crops of the European Russia’s steppe zone. About half of the Russian grain harvest takes place in this area. Areas with different efficiency of agro-potentsial use were identified using the method of spatial expert assessments. The first group includes areas with optimal efficiency of agricultural land use, where the actual yield is close to biopotential. In the second group there are areas with average efficiency, the actual yield is more than 75% of the biopotential. The third group includes areas with low efficiency. The actual yield is less biopotential in this area. Most of the territory of the European Russia’s steppe zone is characterized by low efficiency of agricultural environmental management. There are significant areas of productive arable land, the biological potential of which is not used rationally due to organizational and economic difficulties. The current level of management does not reveal the potential of cultivated soils in each region. Methods and culture of agriculture may differ significantly within the same farm, which leads to variations in actual yields, while reserves increase the actual yield can be up to 50% of its current level. In turn, the identified features can serve as the basis for the development of geographically differentiated programs of rural areas’ integrated development in the steppe zone of European Russia.

GWAS hints at pleiotropic roles for FLOWERING LOCUS T in flowering time and yield-related traits in canola

BackgroundTransition to flowering at the right time is critical for local adaptation and to maximize grain yield in crops. Canola is an important oilseed crop with extensive variation in flowering time among varieties. However, our understanding of underlying genes and their role in canola productivity is limited.ResultsWe report our analyses of a diverse GWAS panel (300–368 accessions) of canola and identify SNPs that are significantly associated with variation in flowering time and response to photoperiod across multiple locations. We show that several of these associations map in the vicinity of FLOWERING LOCUS T (FT) paralogs and its known transcriptional regulators. Complementary QTL and eQTL mapping studies, conducted in an Australian doubled haploid population, also detected consistent genomic regions close to the FT paralogs associated with flowering time and yield-related traits. FT sequences vary between accessions. Expression levels of FT in plants grown in field (or under controlled environment cabinets) correlated with flowering time. We show that markers linked to the FT paralogs display association with variation in multiple traits including flowering time, plant emergence, shoot biomass and grain yield.ConclusionsOur findings suggest that FT paralogs not only control flowering time but also modulate yield-related productivity traits in canola.

Improving the efficiency of a sowing technology based on the improved structural parameters for colters

The paper reports results from research into improving the efficiency of the technological process of sowing agricultural crops based on the theoretical and experimental studies of functional dependences of operations in the course of the technological process on parameters for colters. Their variants have been substantiated, which, in the subsequent synthesis in various combinations, has made it possible to construct, depending on the requirements, a family of versatile, combined, and specialized colters.Based on the comparison of analysis and experimental research into the widely applied designs of colters, as well as the parameters for their operation, we have discovered flaws in operation and established their impact on reducing the yield of grain crops. In addition, we have theoretically substantiated the influence of the type and structure of colters on the interaction with soil and seeds during sowing under different conditions. That has made it possible to establish a correlation between the parameters for colters and operations within the technological process.The data obtained have become the basis for designing new structural elements and types of colters (a family of them) that meet the requirements of the agronomic science and consumers. They improve the technological processes of interaction between their structural parameters (frontal surface, tip, side cheeks) and soil. This improves the formation of furrow for seeds, arranging them evenly for area and depth of covering with moist soil. That improves the germination, development of cultural plants, and increases yields by up to 10 %.These working bodies are capable of row, narrow-row, scattered, anti-erosion planting, as well as sowing sparse shoots; they improve productivity and protect soil from erosion. Thus, the result of the current work is the created and improved family of colters for grain seeders:– with universal tips: a tip colter, an anchor colter, a tip colter with a combined tip, a colter with a combined tip, a colter with a combined tip with cutouts in cheeks and a soil compactor-separator, a tip colter with a guider and adjustable seed reflector; – for narrow rows: a tip colter; – combined: a combined tip colter with a right angle of soil penetration with a guider and a seed reflector; – anti-erosion: a tip colter, an anchor-disk colter with an attachment mechanism, a paw colter.

Role of ABA Signaling in Regulation of Stem Sugar Metabolism and Transport under Post- Flowering Drought Stress in Sweet Sorghum

Sugar remobilization from vegetative to reproductive tissues is an important process that determines grain yield in crops. Sweet sorghum stems store sugar and introgression of Stay green1 (Stg 1) locus from the grain sorghum genotype B35 into the sweet sorghum genotype S35 was previously shown to bring about a 2-fold higher stem sugar accumulation in the near-isogenic line (NIL) S35SG06040. We hypothesized that remobilization of stem sugar augments grain yield on exposure to drought stress and that the phytohormone abscisic acid (ABA) has a role to play in this process. ABA levels were three times higher in the NIL as compared to those in S35 on drought stress exposure. Remobilization of stem sugars in the NIL was evident by the observed decrease in reducing sugar content in the stem but not in the peduncle in response to prolonged drought stress exposure. Drought-induced expression of some ABA response factors (ABFs) as well as invertase and sucrose transporter genes was seen to be higher in the NIL as compared to S35. An over-representation of ABA-responsive elements (ABREs) and sugar signaling motifs in the differentially expressed genes indicated the involvement of ABA and sugar signaling in regulation of their expression. Two ABF genes located on the Stg1 locus showed single nucleotide polymorphism, which possibly accounted for their differential regulation in S35 and the NIL. The results suggest that ABA signaling plays an important role in post-flowering drought-induced remobilization of sugars to the reproductive sinks.

The Rho-family GTPase OsRac1 controls rice grain size and yield by regulating cell division

Grain size is a key factor for determining grain yield in crops and is a target trait for both domestication and breeding, yet the mechanisms underlying the regulation of grain size are largely unclear. Here we show that the grain size and yield of rice (Oryza sativa) is positively regulated by ROP GTPase (Rho-like GTPase from plants), a versatile molecular switch modulating plant growth, development, and responses to the environment. Overexpression of rice OsRac1ROP not only increases cell numbers, resulting in a larger spikelet hull, but also accelerates grain filling rate, causing greater grain width and weight. As a result, OsRac1 overexpression improves grain yield in O. sativa by nearly 16%. In contrast, down-regulation or deletion of OsRac1 causes the opposite effects. RNA-seq and cell cycle analyses suggest that OsRac1 promotes cell division. Interestingly, OsRac1 interacts with and regulates the phosphorylation level of OsMAPK6, which is known to regulate cell division and grain size in rice. Thus, our findings suggest OsRac1 modulates rice grain size and yield by influencing cell division. This study provides insights into the molecular mechanisms underlying the control of rice grain size and suggests that OsRac1 could serve as a potential target gene for breeding high-yield crops.

EXOGENOUS APPLICATION OF VITAMINS IN UPLAND RICE

Vitamin application can optimize plant growth and grain yield of rice crop due to its beneficial effect on many plant physiological characteristics. The present study was conducted to evaluate the effects of niacin and thiamin applied as seed soaking or foliar spray on the morphological and productive characteristics of upland rice crop (Oryza sativa L., cv. Primavera), grown under greenhouse conditions. The experiment was arranged in a randomized block design in a 4 x 2 factorial scheme, with four replicates. The treatments consisted of the application of vitamins (control; 200 mg L-1 thiamin; 200 mg L-1 niacin; and 100 mg L-1 thiamin + 100 mg L-1 niacin) and two application methods (seed soaking and foliar spraying). Morphological and productive characteristics of the rice plants were evaluated. The exogenous application of thiamin and niacin, regardless of the application method, has a beneficial effect on the growth of upland rice plants, but does not increase the grain yield of the crop.

Ecological and economic efficiency of tillage resource-saving technologies

Under existing conditions, intensive exploitation of land resources is accompanied by negative changes in agrogenic ecosystems. As a result of the anthropogenic impact on the soil cover, fertility and yield are reduced. To maintain the equilibrium of agrogenic ecosystems from the effects of anthropogenic factors causing soil degradation and loss of its fertility, it is necessary to introduce new technologies that combine safe ecological principles with the production of a stable yield of grain crops. The use of modern technologies of tillage provides the greatest economic effect and is able to increase soil fertility and the level of ecological purity of agricultural products, which is of great importance.

Grain Farming in Novosibirsk Region in the 1990s: Factors and Dynamics of Qualitative and Quantitative Changes

The article analyzes the changes in the grain economy of the Novosibirsk region in the 1990s in order to identify the agrarian reform results of this period and to form an objective opinion on it. The study of regional aspects of development and operation of grain production, as the country’s most important agricultural sector, — is an effective way to form reliable ideas about the processes in agriculture production generated by radical market transformations of the 1990s. The author examines changes of the key indicators of the industry’s development (dynamics of sown areas and yield of grain crops, gross yield of grain), as well as factors promoting their growth and decrease. The most important task of the research is to identify changes in the quality parameters of the grown grain, agricultural machinery, equipment and facilities of farms and crop processing. The regional grain production is considered in chronological, industrial, organizational and production aspects. It was found out that in the 1990s the regressive tendencies dominated the grain industry of the Novosibirsk region. The farmers, who separated from collective and state farms, did not become the driving force for the agricultural sector of the economy. The personnel and technical base of agricultural enterprises that were the main grain producers decreased; the sown area of grain crops was reduced; the wheat share in them rose, but the grain quality characteristics deteriorated; the amount of protein in grain fell due to inadequate soil fertilization. In the late 1990s the demand for wheat started to fall, but for barley and rye — to grow. The problems with sale of wheat to the food industry enterprises forced its producers to acquire their own mills and bakeries. On the whole, in the 1990s the gross grain production noticeably decreased in relation to the level of the last Soviet five-year plan. The crop productivity remained at the same level.

Impact of Mole Drains and Soil Amendments Application on Management of Salt Affected Soils

Ameliorating the saline-sodic soil process represents an important target in the agricultural security program of Egypt. In this concern, two field experiment were conducted at El-Serw Agricultural Research Station, Damietta Governorate, Agricultural Research Centre Egypt during two successive growing seasons from (2014 2015).and (2015 )Cultivated crops comprised wheat and sunflower in a consecutive sequence, to study effect of applied alternative gypsum, (it is fabricating from some of sugar industry waste in Egypt, which cause environmental pollution problems by mixing some materials or other wastes in order to maximize the benefit and use it as an alternative gypsum) with mole depth and mole spacing on a possible amelioration for some properties of salt affected soils and its productivity of crops. The experimental design was laid out in split-split plots with three replications was followed. The main plots were three levels of irrigation treatments [field capacity (I1), field capacity +10% (I2) and field capacity +20% (I3)]. The sub plots were five mole drains treatments [ without mole(M0),2m mole space with 30 cm depth (M1), 2m mole space with 50 cm depth (M2), 4m mole space with 30 cm depth (M3) and 4m mole space with 50 cm depth (M4)]. The sub sub plots were three alternative gypsum treatments [ Gypsum (control), alternative gypsum one(AG1) and alternative gypsum two(AG2)] at a rate of 5,71 Mg fed.-1 for each of them. The applied alternative gypsum treatments were uniformly spread on soil surface and thoroughly mixed in the top 15 cm. before sowing. Leaching requirements estimated and then amount of irrigation water applied. The most important findings can be summarized as follows: The effect of the depth, distance of the moles with the addition of alternative gypsum treatments and levels of irrigation treatments [field capacity +20% (I3)]. Reduce salinity, acidity, bulk density, penetration resistances , total porosity,. On the contrary, increase the values ​​of hydraulic conductivity, organic matter, Grain yield (Mg fed. -1), Water productivity (kg/m3) and Water consumptive use efficiency (m3fed-1).The highest values ​​of field crops and water use efficiency occurred when the integration and overlap between increasing the depth of mole to 50 cm, decreasing of the mole to 2 meters and field capacity +20% (I3) with the use of alternative gypsum one (GA1) followed alternative gypsum two (GA2) and gypsum. The achieved amelioration in physio-chemical and hydrological properties of the studied soil positively reflected on the increases of grain yields of crops (wheat and sunflower). Finally, the obtained results suggest that this work is considered as scientific and logic fundamental base for a successful agricultural development of such salt affected area as well as possible to increase unite area income

The estimation of productivity of some introduced and local varieties of grain crops in the Republic of Dagestan

Despite the favorable conditions for the cultivation of grain crops in the Republic of Dagestan (i. e. high levels of active solar radiation, sufficient heat, presence of an irrigation network, fertile soils), high yields of grain crops cannot be guaranteed every year, because high humidity, high agro background and strong winds contribute to the spread of fungal diseases, tall height resulted in lodging and deterioration of grain quality. Therefore, the research on the rate of plant response to certain growing conditions and selection of the most adaptive and productive lines and varieties, their introduction into breeding programs and introduction into production are of great importance. Updating of the genetic material through the introduction of new initial forms is one of the ways of successful breeding of the grain crops. In 2015–2017 in the southern lowland of the Republic of Dagestan there was carried out the scientific study of the productivity and resistance to the unfavorable factors of new promising lines and varieties of wheat, triticale and sorghum of different genetic composition and ecological-geographical origin. The research material was the variety samples and lines of wheat, triticale and sorghum, taken both from the world collection of the FSBSI “FITs VIGRR named after N. I. Vavilov”, FSBSI “Agricultural Scientific Center “Donskoy” and Dagestan selection, identified by a complex of breeding significant traits. The highest degree of adaptability in the conditions of Dagestan as demonstrated by the winter soft wheat variety “Fortuna” and the triticale variety “Kaskad”, with the maximum yield of 6.30 and 6.83 t/ha respectively. Among the studied sorghum varieties there should be distinguished the variety “Zernogradskoe 88”, which is characterized with the highest grain yield (4.35 t/ha) and a low height (98 cm) and it ripens before the others because of high adaptability to the growing conditions. The selected varieties of grain crops are of great interest both for breeding work and for direct introduction into the agricultural production of the Republic of Dagestan.

Evaluating Leaf Wax and Bulk Leaf Carbon Isotope Surrogates for Water Use Efficiency and Grain Yield in Winter Wheat

Bulk leaf carbon isotopic composition (δ13Cbulk) has been widely used to investigate leaf level water use efficiency (WUEl) in efforts to boost grain yield relative to crop water use. Although widely used for isotopic analyses, the bulk leaf represents a complex mixture of compounds. Single‐compound isotopic analyses carry diagnostic advantages over bulk analyses in a range of applications and may also serve as surrogates for WUEl and grain yield in crops. This study tests whether compound‐specific carbon and hydrogen isotopes of leaf wax n‐alkanes (δ13Calk and δDalk) and n‐alcohols (δ13Calc) could be used as surrogates for WUEl and grain yield using conventional δ13Cbulk as a reference. Ten winter wheat (Triticum aestivum L.) cultivars were planted under two irrigation treatments (full and deficit irrigation) at Uvalde (wet location) and Amarillo (dry location), TX, during two growing seasons. There were significant relationships between δ13Calk or δDalk and δ13Cbulk, indicating they can all serve as surrogates for WUEl in most cases. Compared with δ13Cbulk, we found stronger relationships between δ13Calk at Uvalde or δDalk under deficit irrigation at Amarillo and grain yield. The δ13Calk also had higher broad‐sense heritability than δ13Cbulk, indicating larger cultivar effects in δ13Calk than in δ13Cbulk. In contrast, the δ13Calc was not consistently related with δ13Cbulk or grain yield. Our study introduces the idea that δ13Calk and δDalk may supplement conventional δ13Cbulk with potential to assist in the breeding process when selecting for high‐WUE and high‐yielding cultivars.