Brown Leaf Rust Research Articles

Characteristics of the spring common wheat variety ‘Balkysh’

One of the recent breeding work results of the FRC KazRC of RAS was the spring common wheat variety ‘Balkysh’, which was included in the State List of Breeding Achievements approved for use in the Middle Volga region in 2021. The purpose of the current study was to characterize the variety under the conditions of the last years of testing in comparison with other varieties. The study was carried out in the fields with gray forest soils of the Tatar RIA, located in the suburbs of Kazan, in 2019–2023. The variety ‘Balkysh’ is not inferior or superior in productivity and protein yield to the varieties most common in the Republic of Tatarstan; the mean productivity of the variety was 4.31 t/ha, protein yield was 0.54 t/ha. The variety is characterized with high productivity stability. The variety had 25 % of gluten in grain, 13.2 % of protein, 94 units of IDK. The peculiarity of the rheological dough properties of the variety ‘Balkysh’ was a low value of flour force with 109 u.a., 61 mm of dough elasticity, 121 u.ph. of dough dilution, which can be used to form grinding grain batches balanced in quality to reduce the load on dough mixing machines. The variety ‘Balkysh’ is characterized with high field complex resistance to major leaf and stem diseases, with not more than 5 % of damage caused with brown leaf and stem rust over the years of testing; powdery mildew resistance during epiphytoty years was not lower than 6 points (a lower one third of the plant was slightly affected). The variety ‘Balkysh’ is characterized as short-stemmed; the mean plant height was 65.7 cm, which is significantly lower than that of the varieties developed by the TatRIA.

СОРТА ДВУРУЧКИ КАК ИСХОДНЫЙ МАТЕРИАЛ ДЛЯ СЕЛЕКЦИИ ЯРОВОЙ ПШЕНИЦЫ В СЕВЕРНОЙ ЛЕСОСТЕПИ ТЮМЕНСКОЙ ОБЛАСТИ

The objective of research is to study the facultative wheat varieties bred by the Krasnodar Research Institute of Agriculture for a set of economic traits and to establish the possibility of using them in the bree-ding of spring wheat in the Tyumen Region. Research was conducted in 2022–2023 on a small experimental field of the Northern Trans-Urals State Agricultural University. The object of research is five facultative wheat varieties (Anka, Afina, Leo, Karavan, Velena) bred by the Krasnodar Research Institute of Agriculture and the standard spring wheat variety Ikar. It was found that facultative wheat varieties, when sown early (soil temperature 8–10 °C), grow and develop well and, at the same time as the standard spring variety Ikar, reach economic grain maturity at the end of August. They form stems 80–90 cm high with shortened lower internodes, dense straw walls (weight of 1 cm of straw is 23.1–27.5 mg, for the standard – 19.7 mg) and are resistant to lodging. In terms of field germination and survival of plants for harvesting, the diurnal varieties exceeded the standard Ikar variety by 13–18 and 12–17 %, respectively. In terms of resistance to brown leaf and stem rust, powdery mildew and septoria, they were rated at 7–9 points. Productive tillering was one and a half to two times higher than that of the standard Ikar variety and amounted to 2–4 stems per plant. Due to the high grain content per ear (23–28 pcs.) and average grain size (34.3–37.1 g), the grain weight per ear was 0.82–1.14 g, which is 0.12–0.44 g higher than that of the standard Ikar variety. In terms of protein and gluten content in grain, as well as grain bulk density, vitreousness, and falling number, the facultative varieties generally met the requirements for valuable and strong wheat. According to the studied economic characteristics, facultative wheat varieties are valuable source material for breeding spring wheat in the Tyumen Region.

Biological Efficiency of Tank Mixtures of Preparations for the Protection of Spring Wheat and Their Effect on Grain Quality

In relatively favorable humidification years, the loss of spring wheat grain harvest from fungal infections – brown leaf and stem rust, powdery mildew, etc., has increased significantly, reaching 25–30% or more of the gross grain harvest. The purpose of the study conducted in 2018–2021 is to improve protection measures against harmful leaf–stem diseases in the conditions of the southern forest-steppe of Western Siberia. Main tasks: monitoring the phytosanitary situation, studying the biological effectiveness of chemical fungicides, biological preparations, growth regulator and tank mixtures, including with liquid complex fertilizer, in spring wheat crops, determining the effect of various preparations on grain yield and quality. The study was conducted in short-term multivariate field experiments. The plot area is 25 m2, the repetition is fourfold, the placement of options is randomized. The effectiveness of the drugs was compared with the control variant without protection from diseases. The use of chemical fungicides, tank mixtures of them with fertilizer, growth regulator in the sowing of spring wheat Omsk 36 provided a high level of biological effectiveness against leaf-stem diseases. The maximum efficiency indicators against brown leaf and stem rust were obtained with the use of tank mixtures of the drugs Soligor + Fast and Furious, Rex Plus + Larixin and Title Duo + Fast and Furious (98.4–99.7%). The best results of protection against powdery mildew were mixtures of drugs Rex Plus + Fast and Furious and Soligor + Larixin, respectively 78.8 and 81.2%. The greatest increases in grain yield to control were obtained in the variants of the use of the drugs Rex Plus + Larixin and Title Duo + Fast and Furious, respectively 1.80 and 1.89 t/ha. The level of economic efficiency in this case was more than 50%. The use of fungicides and tank mixtures significantly increased the nature and weight of 1000 grains. There was an increase in the gluten content from 1.2 to 5.1% in variants with the phytoregulator Larixin, protein – by 0.85–1.71%. In a field experiment similar to the scheme with Melody wheat, conducted in adverse weather conditions in 2020 and 2021, grain yield growth from the use of drugs was not obtained. The main reasons are the dry weather and, accordingly, the low incidence of diseases in the crop. Treatment with Larixin and its tank mixtures with Title Duo, Rex Plus and Soligor fungicides significantly increased the protein content in the grain by 0.80–1.50%, gluten – up to 2.0%. The obtained results testified to the high biological and economic efficiency of the use of modern fungicides and tank mixtures with a growth regulator and fertilizer in conditions of high infestation of spring wheat with leaf–stem diseases.

Effectiveness of fungicidal protection of spring wheat against powdery mildew and tan spot

The results of the study of the effectiveness of plant protection products against powdery mildew (Blumeria graminis) and tan spot (Pyrenophora tritici-repentis) for spring wheat are presented. It has been noted that the probability of mass destruction of crops by phytopathogens is determined by the stock of the infectious beginning of pathogens, the susceptibility of the host plant and the favorable weather conditions for their development and spread. The experiment was carried out using the methods generally accepted in the Russian Federation. During the observation period, the degree of plant damage of more than 20% in the heading phase was noted in 46% of the years of observation (in 2009, 2013, 2014, 2016, 2017). Epiphytotic development of powdery mildew together with brown leaf rust (Puccinia triticina Eriks.) was registered in 2013–2014 and 2016–2017. For 2009–2019 the degree of plant damage of more than 20% in the heading phase was noted in 46% of the years of observation (in 2009, 2013, 2014, 2016, 2017). Effective protection of wheat against powdery mildew (75–87%) was provided by fungicides based on 2–3 active ingredients. The biological effectiveness of the biofungicide (Bacillus subtilis) was manifested only in the years with moderate wheat damage and did not exceed the average level of 58%. It is more expedient to carry out operational control of yellow spotting of wheat leaves with preparations based on such active substances as "azoxystrobin + epoxiconazole", "tebuconazole + propiconazole". The level of statistically significant yield preserved due to fungicidal protection during the years of depression was 5–6%, with a moderate development of leaf diseases due to chemical fungicides - 18%, and the biological product provided an increase in productivity of 9%. During the years of epiphytoties, the chemical protection of crops retained an average of 24% of the wheat yield, polycomponent preparations had the best performance and stability of action, and the biological protection of plants under these conditions was ineffective.

Распространение фитопатогенов на зерновых яровых культурах в Уральском регионе

Abstract. In the Ural region over the past decade, the following changes have occurred in agricultural technologies: an increase in the share of stubble backgrounds for the cultivation of grain crops, which entails special phytosanitary risks. Climate change has been expressed in progressive warming over the past 90 years. The purpose of the study was to establish the effectiveness of the fungicidal protection of wheat against a harmful phytopathogen – brown rust – in modern conditions. Methods of All-Russian institute of plant protection were used. Scientific novelty. The modern distribution of phytopathogens on grain crops in the region was assessed and effective preparations were proposed to protect wheat from leaf rust. Results. Moderate and epiphytotic development of leaf phytopathogens on spring wheat took place in 46 % of years. It is during these years that the use of fungicidal plant protection products is mandatory to maintain wheat yields. Biological efficiency of more than 90 % against the local racial composition of brown leaf rust was provided by chemical preparations, variants with combinations of active ingredients propiconazole + tebuconazole and thiophanate-methyl + epoxiconazole were especially distinguished. The use of chemical fungicidal plant protection in the years of epiphytoties retained 32–45 % yield or 7.0–9.4 c/ha. In years with moderate leaf infections, the increase in productivity averaged 3.1–4.8 c/ha. In years with active dry phenomena in the second half of the growing season, the manifestation of leaf rust was single and had no economic significance. The method of immune protection can be actively used, the set of spring wheat varieties with specified parameters for the Ural region is quite wide.

Колекція жита озимого Національного центру генетичних ресурсів рослин України як основа для створення селекційно-цінних і стабільних генотипі

Goal. To form a collection of winter rye as a basis for the creation of selection valuable and stable genotypes, to identify sources of group resistance to diseases, against lodging, and to determine the selection value and stability of the best samples in terms of productivity in the conditions of the Eastern part of the Forest Steppe of Ukraine. Methods. General scientific (analysis and synthesis) — for differentiation and generalization of the obtained results, field — for determining the resistance of samples to diseases and against lodging, and dispersive — for determining the manifestation of valuable economic traits, and their variations and assessing the reliability of experimental data. Results. 12 sources with high levels of manifestation (7–9 points) of group resistance to diseases were identified, of which 3 combine resistance to snow mold, powdery mildew, scolecotrichosis, and brown leaf rust — Kompozytne, Intensyvne 4 (UKR); Sybyr (RUS) and 8 — with resistance to lodging, in particular: Lira (UKR); Rifle (CAN) and others. Among the best samples in terms of productivity, the variability of its manifestation was determined, which according to the coefficient of variation (CV, %) was 9.1–31.9%, the selection value (Sc) — 313.3–568.4, respectively. It was established that the share of samples with the genotypic ability to form high yield stability was 21.4%, the average was 50.0%, and the low was 28.6%. Conclusions. The collection of winter rye of the National Center of Plant Genetic Resources of Ukraine was formed, which was the basis for the creation of breeding valuable and stable genotypes. The most significant genotypes, which combine high breeding value and yield stability, include varieties of domestic selection — Kompozytne (CB = 9.1%; Sc = 541.4) and Stoir (CB = 9.7%; Sc = 527.6) — at a level of more than 20% to the standard.

Estimation results of the spring bread wheat varieties on disease resistance in the Kazan Research Center

In the Republic of Tatarstan, due to favorable soil-climatic and market conditions, spring wheat production is developed, but wheat grain yields are limited by a number of unfavorable factors, one of which is a spread of fungal diseases. At the same time, the pressure of pathogenic fungi makes it possible to carry out fruitful breeding work in Tatarstan on resistance to diseases, which is on of the main activity of the Kazan Research Center of the RAS. The purpose of the current study was to estimate ten new varieties for resistance to major fungal diseases. The study on resistance to leafy diseases, such as powdery mildew, stem rust, brown leaf rust, dark brown leaf blotch was carried out at a natural infectious background, to kernel smut on an artificial infectious background inoculating seeds with spores of kernel smut. The study was carried out between the years of 2017 and 2021. The analysis for the possible presence of stem rust resistance genes was performed by a PCR analysis. As a result of the study, there was found out that the varieties ‘Sto let TASSR’, ‘Balkysh’, ‘Khazine’, ‘Chistopolskaya’, ‘Bulyak’ had a complex resistance to all studied diseases. The variety ‘Sitara’ had a strong field resistance to powdery mildew and kernel smut. The variety ‘Barakat’ had a strong field resistance to powdery mildew and leaf rust. The variety ‘Nadira’ was moderately resistant to powdery mildew and dark brown leaf spot. The varieties ‘Ekada 265’ and ‘Ekada 282’ were highly resistant to local stem rust populations. The molecular genetic estimation of the stem rust resistant varieties of spring bread wheat ‘Chistopolskaya’, ‘Sto let TASSR’, ‘Balkysh’, ‘Ekada 282’ for the identification of effective Sr-genes has shown that their resistance is apparently regulated by the Sr31 gene.

Infestation of soft spring wheat by leaf diseases depending on nitrogen nutrition

Infestation of soft spring wheat plants depends on the growth stage and weather conditions of the growing season. Plants have the highest resistance to brown rust in the tillering stage. Brown rust developed in 2014 throughout the growing season. The lowest infestation intensity was during tillering – booting stage, which did not change from the experiment variant – 5.0 %. The lowest spread of brown rust was in the tillering stage – 10 %, in the booting stage – 40 %. The resistance was assessed 8 points. In the earing stage, the infestation intensity increased in no fertilizer variants and P30K30 to 8.0–8.2 % or by 60 % with a resistance of 7 points. This indicator in the variants with nitrogen fertilizers was 4.1–4.3 % with a resistance of 8 points, but all stems were infected (100 % spread). Affected leaves were in the middle layer, as their resistance by E. E. Saari and J. M. Prescott scale was at 5 points. Plants had the least resistance to brown rust in the milk stage of soft spring wheat grain. The intensity increased to 15.2–18.7 % or 2.1–4.7 times compared to the earing stage. The lowest resistance was assessed 6 points. All leaves were affected (resistance by E. E. Saari and J. M. Prescott scale – 1 point). In 2015, brown rust appeared in the milk stage of soft spring wheat grain. However, the infestation intensity was insignifcant – 5.0–6.5 % depending on the experiment variant. The prevalence of brown rust decreased from 60 % in unfertilized areas to 30 % on phosphorus–potassium background and up to 10 % with nitrogen fertilizers. Plant resistance was high – 7–8 points depending on the experiment variant. Powdery mildew develops throughout the growing season of both research years. In 2014, the infestation intensity is the lowest in the tillering stage – 7.7–8.0 % with 50 % spread, with the resistance of 7 points. In the booting stage of plants, the infestation intensity increased to 44.1–46.8 % or 5.8–5.9 times compared to the tillering stage. All plants were affected, and the resistance was 3 points. In subsequent stages of growth, the intensity of powdery mildew increased. Thus, in the earing stage this indicator increased to 65.1–69.2 % or 8.5–8.7 times, and in the milk stage – 9.5–9.7 times compared to tillering depending on the fertilizer. The stems of soft spring wheat were all affected, and the resistance was 2 points. Key words: brown leaf rust, powdery mildew, infestation intensity, spread, resistance.

Phytosanitary diseases’ monitoring of breeding crops of winter cereals and limitation of their harmfulness

Studies on fungicides’ effect on new varieties and lines of winter triticum-wheatgrass hybrids and winter triticale were conducted in the conditions of the Central zone of the Russian Federation. The results showed that the preparations Alto Super, CE and Falcon, CE effectively cope with the suppression of brown leaf rust on new varieties in the dosages recommended by manufacturers. They allow to reduce the prevalence of brown rust by 15.2-35.6%, the development degree of the disease - by 9.9-18.0%. The spread of septoria decreases by 7.7-8.8%, the intensity of plant damage - by 1.0-2.2%. The use of these preparations allowed to increase crop yields by 1.2-1.7 times compared to the option with no fungicidal treatments.

English

Brown leaf rust severely affects the production of wheat crop and causes economic losses worldwide. In the present study, evaluation of the locally developed wheat cultivars collection consisting of 133 varieties and lines was done to assess local diversity against leaf rust disease and yield attributes under natural conditions in Faisalabad, Pakistan. For this purpose, a field trial was conducted in Faisalabad, Pakistan under a randomized complete block design (RCBD). Various multivariate analyses were carried out including analysis of variance (ANOVA), correlation analysis, principal component analysis and cluster analysis to assess varietal response under rust diseased conditions. Twenty-six cultivars were shown to have an resistant (R) type response; while moderately resistant (MR),moderately resistant moderately susceptible (MRMS), moderately susceptible (MS) and susceptible (S) responses were demonstrated by 47, 16, 16, and 28 germplasm accessions, respectively. Analysis of variance indicated that, all the verities have highly significant difference for all the characters. The Pearson’s correlation coefficients revealed that grain yield per plant was positively correlated with most yield attributes, but negatively correlated with disease severity. Principal component (PC) analysis indicated that five PCs have an Eigenvalue >1 and contributed 78.4% to the total variability while rest of 6 attributes contributed (21.6%) between wheat cultivars evaluated for different characters. Cluster analysis categorized the 133 genotypes into five different clusters. The members of the 4 th cluster showed maximum divergence from the members of 3 rd clusters. On the other hand, the members of 1 st and 2nd clusters showed the maximum similarities according to D2 statistics. Scatter plot showed that the genetic variation in the studied germplasm accessions and this diversity can be used for breeding programs aimed at improvement of disease resistance in the wheat germplasm. It concludes that there is significant diversity among the locally developed wheat germplasm for both leaf rust resistance and yield attributes. The present study, clearly emphasize the importance of resistant varieties which are great edge to the farmers in order to prevent yield losses

ГЕНЕТИЧЕСКИЕ РЕСУРСЫ ЯРОВОЙ ПШЕНИЦЫ, УСТОЙЧИВЫЕ К БУРОЙ РЖАВЧИНЕ

Brown (leaf) rust is the most common wheat disease and is found on all continents and countries where this crop is cultivated. Spring wheat occupies about 9 million hectares in Northern Kazakhstan. According to M.K. Koishybaev, brown rust and Septoria spot often appear together in the northern region, when they spread during the shooting-earing period and in case of wide progression, yield losses reach 30-40%, at the beginning of the filling- grain milk ripeness period - 7-10%. Among plant protection measures from various diseases caused by parasitic fungi, bacteria, viruses, as well as from damage by various insects, the most effective is introduction of immune varieties into the culture. The aim of our research is to study the genetic resources of spring crops and to identify new sources and donors of leaf rust resistance in northern Kazakhstan. In total, 150 varieties of spring bread wheat of various ecological and geographical origin were selected. The collection seed plot of spring soft wheat was sown in 2 replications, with a plot area of 2m2. The brown rust plot was lain according to the methodology of the State Variety Testing of Agricultural Crops. As a result of the work carried out, thirty-one new sources of resistance to leaf rust were identified: k-29288 (Georgia), Stendal (Italy), Sriblyanka, PKHRSV 02 (Ukraine), Frontana (Brazil), Marquis (Canada), etc. Seven varieties were characterized by resistance to leaf rust and a complex of economically valuable traits: Lutescens 415/00; Lutescens 120-03; Lutescens 16-04; Haamam 4; Sigma; Sibirskaya 17; Chelyaba early. The selected samples are of great interest for practical breeding and will be used to create new varieties of spring wheat with high productivity and resistance to leaf rust.

Breeding progress of disease resistance and impact of disease severity under natural infections in winter wheat variety trials

Key messageBreeding progress of resistance to fungal wheat diseases and impact of disease severity on yield reduction in long-term variety trials under natural infection were estimated by mixed linear regression models.This study aimed at quantifying breeding progress achieved in resistance breeding towards varieties with higher yield and lower susceptibility for 6 major diseases, as well as estimating decreasing yields and increasing disease susceptibility of varieties due to ageing effects during the period 1983–2019. A further aim was the prediction of disease-related yield reductions during 2005–2019 by mixed linear regression models using disease severity scores as covariates. For yield and all diseases, overall progress of the fully treated intensity (I2) was considerably higher than for the intensity without fungicides and growth regulators (I1). The disease severity level was considerably reduced during the study period for mildew (MLD), tan spot (DTR) and Septoria nodorum blotch (ear) (SNB) and to a lesser extent for brown (leaf) rust (BNR) and Septoria tritici blotch (STB), however, not for yellow/stripe rust (YLR). Ageing effects increased susceptibility of varieties strongly for BNR and MLD, but were comparatively weak for SNB and DTR. Considerable yield reductions under high disease severity were predicted for STB (−6.6%), BNR (−6.5%) and yellow rust (YLR, −5.8%), but lower reductions for the other diseases. The reduction for resistant vs. highly susceptible varieties under high severity conditions was about halved for BNR and YLR, providing evidence of resistance breeding progress. The empirical evidence on the functional relations between disease severity, variety susceptibility and yield reductions based on a large-scale multiple-disease field trial data set in German winter wheat is an important contribution to the ongoing discussion on fungicide use and its environmental impact.

Development and distribution of brown leaf rust of winter wheat depending on weather conditions, varietal composition and methods of protection

Development and distribution of brown leaf rust of winter wheat depending on weather conditions, varietal composition and methods of protection

Prevalence and harmfulness of winter wheat brown leaf rust (Puccinia recondita Rob. ex desm. f. sp. tritici) in the Southern Steppe of Ukraine

Apart from making farmers adapt agricultural technologies to new, more arid conditions in order to obtain sustainable and high yields, global climate change is also known to alter the pathogenicity of plant pathogens, the biological cycle of which is tightly associated with environmental factors. One of the most common diseases of winter wheat is brown leaf rust, caused by Puccinia recondita Rob. ex Desm. f. sp. tritici. In terms of its harmfulness and prevalence among other leaf and stem diseases, brown leaf rust is comparable to yellow and stem rust, septoria leaf blotch and other leaves blotches. Under arid conditions of the Southern Steppe of Ukraine, the disease manifests itself once every five years provided that sufficient moisture, indicated by the hydro-thermal index above 1.0, is present during the spring and summer vegetation periods. The main factor influencing the intensity of pathogen development is moisture supply from April to June (ΣTP> 50 mm). In 2019, the amount of precipitation during this period was 194 mm, which led to the disease development at the level of 18.4% with a spread of 27.2%. Productivity of winter wheat varieties such as Antonivka, Blago and Maria was reduced by 10.8-11.3%, when infected in the phase of milk grain stage (stages 73-77 on the BBCH scale), while net photosynthesis productivity decreased by 14.2-14.3%, which translates to lower average yields of 2.3-3.1 t/ha. To maximize the productive potential of varieties and effectively control the development of the causative agent of brown leaf rust in winter wheat under favourable conditions for epiphytic development, the application of systemic fungicides with long-term protective effect imparted by the chemical group of triazoles (Colossal e.c., 1.0 l/ha ) is recommended in stages 69-71 on the BBCH scale. This provides not only reliable crop protection (Eff.: 77.9-82.0%), but also yields at the level of 3.3 - 4.6 t/ha, depending on the variety under non-irrigated conditions.

Brown rust damage of the winter wheat varieties with different levels of resistance to the pathogen in the south of the Rostov region

The purpose of the current work was to study the winter wheat varieties artificially infected with the North Caucasian population of brown rust to identify a damage degree. The study was carried out in two stages on two sets (8 and 10) of varieties with different level of resistance to the pathogen. The trials have established a high damage degree of rust on susceptible varieties, which resulted in productivity decrease from 16.3 to 32.2%. Among the varieties with the maximum damage degree, there was identified the most resistant variety ‘Tarasovskaya 29’ which, when completely (100%) damaged by the disease, showed a minimum productivity decrease, no more than 10.6%. The varieties being poorly susceptible to brown leaf rust reduced the productivity from 11.2% to 20.7%. The smaller indices of productivity decrease among this group were shown by the variety ‘Spartak’. Among the five varieties that showed moderate leaf rust damage, there were different degrees of productivity decrease. The variety ‘Donskaya Yubileynaya’ artificially infected with brown rust, showed a minimal productivity decrease and its structural elements, and it could be identified as the leaf rust resistant variety like the variety ‘Tarasovskaya 29’. When predicting the brown leaf rust epiphytoty, the susceptible and half-resistant wheat varieties require obligatory protection with fungicides.

Phytopathological Assessment of Lines of Common Winter Wheat to the Cause of Brown Leaf Rust (Puccinia recondita f. sp. tritici)

The study was conducted in the period 2017-2019 in the experimental fields of the Institute of Plant Genetic Resources K. Malkov” in Sadovo, near Plovdiv, Bulgaria. At the infectious area, the immune responses of twenty-two genotypes of common winter wheat to the causative agent of brown leaf rust - Puccinia recondita f. sp. Tritici were tested The line MX 289/2048 has shown high resistance to the pathogen, and seven samples are characterized by a stable reaction. The biggest share of the studied breeding materials showed average resistance to the phytopathogen. A comparison of the indicators of grain weight in the central spike and 1000 kernel weight was made for samples grown on an infectious site and under natural field conditions. The obtained results showed an exceeding the values of the trait in favor of the samples grown under natural field conditions. It was found that the greatest influence on the traits grainsweight in the central spike and 1000 kernels weight has the year of cultivation. To assess the genetic diversity, a cluster analysis was applied, in which the selection materials were grouped into five main cluster groups. The lines MX 286/1777 and MX 270/3461 are characterized by the greatest genetic proximity, and the line MX 285/1058 is genetically the most distant compared to the samples from the first cluster group.

Formation of phytopathogenic fond in agrocenoses of cereals of the right-bank Forest-steppe of Ukraine

Тhe features of the formation of phytopathogenic fond of micromycetes, pathogens of cereal diseases of the right-bank Forest-steppe of Ukraine for 2004– 2019 are analyzed. The leading place in the phytopathogenic complex is occupied by micromycetes, among which the pathogens of root rot and powdery mildew dominate. The area of crops affected by these diseases is 32.5–75.0%, and in some years reaches to 100%, the spread of diseases — 4.2–19.8%, the development of diseases — 1.6–14.0%. In addition, leaf septoria and pyrenophorosis predominate in agrocenoses of winter wheat, at spring wheat — dark brown spotting; spring barley — spotting and rhynchosporium. Olive mold and fusariosis dominate among the diseases of the head. During the study period, a significant development of winter wheat pyrenophorosis was noted — 5.1–16.8% (max 35%), brown leaf rust spread on spring wheat — 4.6–24.4% (max 45%) and spread of spotting of spring barley — up to 50% (max 100%). Exceeding the threshold of harmfulness of root rot (in 2.8–4.0 times), powdery mildew of wheat (in 6.3– 8.2 times) and spotting of barley (in 2.5 times) leads to excessive use of fungicides and causes increased environmental risks in agrocenoses, chemical and biological pollution of agroecosystems, which significantly affects the quality and safety of products.

Integrated protection of winter wheat from a complex of harmful causes in european non-chernozem region of the RF

The results of many years of research on the effectiveness of the integrated use of crop protection means and fertilizers with the application of various tillage systems for cultivation of winter wheat of Moskovskaya variety 39 are presented. The studies were conducted in the European nonchernozem soil of Moscow Region on sod-podzolic medium loamy medium-cultivated soil. It was shown that weeds are mainly represented by broadleaved species with an amount of 270 to 370 pcs/ m2. Among pests, cereal aphids and capsid bugs dominate. Among diseases, Helminthosporium and Fusarium root rot (up to 30–40%) and aerogenic infections – brown leaf rust (15-28%) and leaf spot (17-25%) were noted. Studies showed high individual effectiveness in eliminating harmful causes by using appropriate means of protection – seed disinfectants, herbicides, fungicides and insecticides. Weed infestation decreased by 78-85%, root rot development – by 78-81, leaf diseases – by 91-98, pests – by 78-100%. At the same time, the weak effectiveness of the Alto-super fungicide against Septoria and Karate insecticide against wheat thrips was noted. The effect of protective measures on the stored crop was as follows: seed disinfectants – 18%, insecticides – 21, herbicides – 39, fungicides – 22%. The highest economic effect was obtained with the integrated use of plant protection products – up to 1.07 t / ha of grain. At the same time, the quality of grain, content of protein and gluten, and grain class increased. The economic effi ciency of the integrated protection system ranged from 4.7 to 8.1 roubles for each rouble spent. The best result in terms of economic effi ciency was obtained with moldboard tillage and the use of a full dose of NPK90 mineral fertilizers and a full integrated protection scheme.

Yield and resistance to leaf diseases of modern winter bread wheat varieties under the limiting influence of biotic factors

Aim. To identify new sources of resistance of winter bread wheat to powdery mildew,Septoria leaf blotch, brown leaf rust and of high yield capacity under the conditions of the northeastern part of the Left-Bank Forest-Steppe of Ukraine. Results and Discussion. The study of modern varieties of winter bread wheat onepiphytoties identified 88 sources with high (7-9 points) individual resistance to leaf diseases wereidentified, including 40 sources of resistance to powdery mildew, 20 sources of resistance to Septoria leaf blotch, and 28 sources of resistance to brown leaf rust. We selected 12 accessions of the highest breeding value due to their group resistance to powdery mildew, Septoria leaf blotch and brown leaf rust, among which domestic accessions bred by the Institute of Plant Physiology and Genetics of NAS of Ukraine and the VM Remeslo Myronivka Institute of Wheat of NAAS were predominant. As to foreign institutions, varieties bred at the RUE "Scientific and Practical Center for Agriculture of Belarus of NAS" stood out. Among the mid-tall sources of group resistance to powdery mildew, Septoria leaf blotch and brown leaf rust, three domestic genotypes with high yields (116-155% related to the check variety) were distinguished: Darynka Kyivska,Amina, Vezha Myronivska (UKR). Among the semi-dwarfs, Novosmuhlianka and Koliada (UKR) were the best varieties in terms of yield (152% related to the check variety). Conclusions. It was determined that there were moderate or strong positive correlationsbetween the resistance of the winter bread wheat accessions under investigation to leaf diseases on epiphytoties and yield capacity (r = 0.47-0.60) with the greatest significance (P <0.01). At thesame time, Septoria-induced reduction in the yields was more conspicuous than that caused by brown leaf rust and especially by powdery mildew. The identified winter bread wheat sources of resistance to powdery mildew, Septoria leaf blotch, and brown leaf rust as well as of high yield

СОРТ В СИСТЕМЕ ЗАЩИТЫ ЯРОВОЙ ПШЕНИЦЫ ОТ ЛИСТОСТЕБЕЛЬНЫХ БОЛЕЗНЕЙ

In 2018, 21 varieties of spring soft wheat were recommended for cultivation in Tatarstan, with a specific weight of 79.2% in the structure of the harvested area under spring wheat. Determining the degree of resistance to diseases of these varieties allows you to properly plan protective measures throughout the republic. Studies were conducted in 2015-2018 on the experimental fields of Tatar Scientific Research Institute of Agricultural Sciences. Varieties, recommended for cultivation, differ in the degree of field resistance to the main fungal diseases. The Ester and Zlata varieties have the maximum field resistance to powdery mildew (average 7 points), Chelyaba Stepnaya and Tulaykovskaya Nadezhda varities have the minimum (4 points). Most spring wheat varieties are susceptible to the local brown leaf rust population. The following varities remain resistant to leaf brown rust: Tulaykovskaya 10, Ekada 113, Tulaykovskaya 108, Arkhat, Ulyanovskaya 105, Tulaykovskaya Nadezhda. Moreover, the homogeneity of the genetics of most resistant varieties (caused by the resistance gene Lr19) does not allow epiphytoties of leaf brown rust in the future. According to the 2016-2018 studies, the least degree of stem rust damage was observed in the varieties: Tulaykovskaya 10, Ekada 113, Tulaykovskaya 108, Arkhat, Ulyanovskaya 105 and Tulaykovskaya Nadezhda, on average, 5-10%. There are no varieties, which are immune to stem rust. In 2017 in the conditions of the massive development of dark brown spotting, there were no signs of disease on the leaf of Kazanskaya Yubileinaya variety, the resistance of this variety is determined by the Sb1 gene. The maximum susceptibility to dark brown leaf spotting has the Simbirtsit and Idelle varieties. An integrated resistance to the studied diseases have varieties: Ekada 113, Tulaykovskaya 108 and Arkhat.