Non-resistant Varieties Research Articles

ETHYLENE AND FATTY ACIDS AS MARKERS OF STRESS RESISTANCE IN WINTER WHEAT

There are a number of global problems in the agricultural sector of Ukraine, including environmental factors such as climate change, floods and droughts, which cause damage to plant tissues and significant losses of food crops. A significant obstacle to the development of agriculture and food security in Ukraine are biotic factors, in particular pathogenic bacteria, viruses and microfungi. Fusarium are the most widespread and aggressive pathogens to grain crops, especially to wheat. These obstacles can be overcome by introducing wheat varieties resistant to Fusarium into agronomic practice. However, selection of resistant wheat to fusariosis along the path of traditional centuries-old selection is a laborious and expensive road. However, selection of resistant wheat to fusariosis along the path of traditional centuries-old selection is a laborious and expensive road. Therefore, the search for new effective tools that will facilitate the selection of plants with desirable characteristics at the early stages of breeding programs is an urgent task. Methods. Wheat varieties of different resistance to abiotic and biotic factors in field conditions were used in laboratory studies: resistant, semi-resistant and non-resistant. Ethylene and fatty acids were determined by gas chromatographic methods. The results. Patterns of ethylene and fatty acid synthesis of winter wheat varieties with different resistance to biotic and abiotic factors were revealed. Resistant varieties are characterized by a significantly higher content of these compounds compared to non-resistant varieties. A similar regularity was found in relation to the lodging of plants: the higher the content of these compounds, the greater the resistance to lodging. Conclusions and perspectives. This article describes two methods of assessing the resistance of winter wheat to abiotic and biotic stresses, which can be implemented in breeding programs.

Major cucumber diseases and the crop immunity

In Ukraine, cucumber (Cucumis sativus Linneus) annually occupies about 20 % of the total area of all vegetable crops sown in the open ground or 52.6 thousand hectares. The main reason that significantly reduces the quantitative and qualitative indicators of this vegetable crop's main valuable economic traits is the high incidence of commercial crops with diseases, especially downy mildew (Pseudoperonospora cubensis (Berk and M.A. Curtis) Rostovtsev). Since 1985 in Ukraine, this cucumber disease in the open ground on nonresistant varieties has continuously had intense development, in some years the development – by the type of epiphytotic. Simultaneously, the shortage of commercial yield of this vegetable crop due to the defeat of this disease under the field conditions can reach the level of 50–80 % or more, seed loss – 25–70 %. One of the main reasons for significant losses of commercial yield and seeds of gherkin cucumber under the conditions of its cultivation in the open ground is recognized as the high susceptibility of samples to some diseases, particularly downy mildew (Pseudoperonospora cubensis (Berk. and M.A. Curtis) Rostovtsev). Unfortunately, this problem has remained relevant for Ukraine over the past few decades. So, obtaining the initial material of a gherkin cucumber with a harmonious combination in the genotypes of a complex of various valuable economic characteristics (yield, quality, resistance to diseases, chemical substances content, suitability for various types of processing) and creating a modern competitive, innovative product (variety, hybrid) on its basis remains a relevant and priority task for domestic agricultural science at present. At the same time, scientists have proved that introducing complex (integrated) systems into production, which expect the biologization of protection with its transfer to an ecological and economic basis, is recognized as the most promising today. We suggested using resistant varieties (hybrids) in such integrated systems that provide the highest economic effect.

Simulated drift of dicamba and 2,4-D on soybeans: effects of application dose and time

The use of soybean varieties resistant to the herbicides dicamba and 2,4-D may lead to drifts towards areas grown with non-resistant varieties. The aim of this study was to evaluate the effects of dicamba and 2,4-D underdoses applied at the phenological stages V4 and R2 of soybeans. Two experiments were conducted with dicamba or 2,4-D in a randomized block design with four replications. The 4 × 2 + 1 factorial scheme was composed of four doses (0.028, 0.28, 2.8, and 28 g ae ha−1) of dicamba or 2,4-D applied at two phenological stages (V4 and R2) + a control treatment (without herbicide application). Dicamba underdoses caused damage to soybean crop affecting its vegetative growth and yield; the injuries caused by 2,4-D were neither enough to damage crop nor affect yield components. Dicamba underdoses applied at V4 caused injuries of up to 41%, while in R2 they reached 70%. Plant height decreased by up to 61% when treated with dicamba. Soybean yield was reduced by 29 and 76% when the simulated drift occurred at V4 and R2, respectively, and at a dose of 28 g ae ha−1 of dicamba. For the tested underdoses, only 2,4-D had no effect in soybean crop yield.

Clomazone Aktif Maddesinin Yarı Kurak Koşullarda Geleneksel Pamuk (Gossypium hirsutum L.) Tarlalarında Yabancı Ot Kontrolünde Çıkış Öncesi Herbisitlerle Tank Karışımı

One of the critical components of successful cotton production is effective weed management. Since cotton cannot compete sufficiently with weeds, especially in the first six weeks, a certain number of weeds significantly reduces cotton yield. In addition, weeds can make cotton harvest difficult and contaminate cotton fiber. The main preferred control method for broadleaf weeds in the conventional cotton of Turkey (non-tolerant and non-resistant varieties) is the use of pre-emergence herbicides. However, since there is not much information about the effects of mixtures of different pre-planting herbicides, the aim of this study is to evaluate the efficacy and selectivity of herbicides applied as a pre-emergence mixture in cotton. The randomized complete block design (RCBD) with four replications and eleven treatments was used in the field experiment. The plots were established to 20 square meters (4 m x 5 m). Herbicide applications in the study were carried out in Diyarbakir in 2015, and dual mixtures of clomazone, fluometuron, oxyfluorfen, and pendimethalin were used with different mixtures and doses. Clomazone 0.2 l ha-1 + fluometuron 1,5 l ha-1, clomazone 0.2 l ha-1 + fluometuron 2 l ha-1, clomazone 0.4 l ha-1 + pendimethalin 1.5 l ha-1 and clomazone 0.3 l ha-1 + pendimethalin 2 l ha-1 mixture was found to be complete weed control efficiency. This result shows that mixtures with clomazone active ingredient increase in the efficiency of herbicides pre-planting. Oxyfluorfen mixtures showed the most hazardous damage in terms of product selectivity. The highest cotton yield (> 5 t ha-1) was obtained from the application of mixes of clomazone 0.30 l ha-1 + fluometuron 2 l ha-1 and clomazone 0.2 l ha-1 + fluometuron 1.5 l ha-1, respectively.

PR-proteins as markers of winter wheat (<i>Triticum aestivum L.</i>) resistance to leaf pathogens

Using real-time PCR analysis, the constitutive expression of PR-protein genes encoding thaumatin-like protein (TLP), peroxidase III (TaPero), chitinase (Chitin), glucanase (Glucan), protease inhibitor (PrInh), oxalate oxidase (OxOxid) and lipid transfer protein (Ltp) was studied in collection varieties of winter wheat. It has been shown that plants of varieties with increased resistance to a complex of leaf pathogens have higher constitutive expression levels of Chitin and PrInh genes, and, to a greater extent, of TLP, TaPero and Glucan genes, compared with non-resistant varieties. It is proposed to use constitutive levels of expression of TLP, TaPero and Glucan genes for the selection of winter wheat varietal samples with increased resistance to the complex of leaf diseases.

Ampelographic collection of NSС «V.Ye. Tairov IVW», current trends in studies and prospects of usage

The aim of our research was to analyze the composition of an ampelographic collection of the V. Ye. Tairov Institute of Viticulture and Winemaking by geographical origin of varieties, application, ripening period, berry color, flavor profile, seed development, winter hardiness and frost tolerance, and resistance to major fungal diseases. To enrich the database of varieties – sources and donors of valuable traits via analysis of data on expression of adaptability and performance characteristics. Results and Discussion. At present, there are 736 varieties in the ampelographic collection of the V. Ye. Tairov Institute of Viticulture and Winemaking. The largest portion contains Ukrainian, Russian and Moldavian varieties. More than half (59 %) are table varieties; one third (31%) are wine ones; and 10 % are universal varieties and varieties that are still being studied. As to the ripening period, a group of early-ripening, mainly table varieties (23 %), stands out. The most numerous portions of the collection are mid- and late-ripening varieties (17 % each). The percentages of early-middle and mid-late varieties are similar (11 and 12 %, respectively). Among the berry colors, white and its variations (yellow, yellow-green, amber, etc.) account for 44 %; black – for 23 %; and pink – for 6 % of the collection accessions. There are varieties with red-violet, white-pink, yellow-pink, pale red or bright red berries. Significant diversity was also found in flavor characteristics of the collection accessions. Even in the largest group with so-called “simple taste” (86 % of the collection accessions), varieties with bright prune, solanum, flower, honey and other aromas were found. Varieties with muscat flavor remain in high demand on the market. It was found in 12.5 % of varieties, which can be used in further breeding process. The collection contains 7 % of seedless varieties. Among the collection accessions with their diverse genetic and geographical origin, 82 % have low winter hardiness and frost tolerance and are damaged even at –20 – 21oC. They are mainly European varieties without genetically determined mechanisms of protection against low temperatures and overwintering conditions. 17.9 % of the collection accessions vary from relatively frost tolerant (−22 – 24oC) to frost tolerant (−26–28oC). More than half of the collection accessions (64.5 % ) are susceptible to fungal diseases, since they derive from non-resistant varieties. They are mainly intraspecific Vitis vinifera L. varieties. They are used in crosses as donors of product quality characteristics. A third of varieties showed relative resistance to diseases (6–7 points on a 9-point scale (Bankovska, 2007)). They are widely used in further crosses to obtain genotypes with genetically determined disease resistance. Conclusions. The observations and analysis of adaptive and productive characteristics of 735 collection varieties of the V. Ye. Tairov Institute of Viticulture and Winemaking have resulted in enrichment of the database both with introduced and with our own valuable varieties - donors.

Defensive glycoproteins from sugarcane plants induce chemotaxis, cytoagglutination and death of smut teliospores.

Sugarcane produces and secretes high molecular mass glycoproteins (HMMG) in response to pathogenic infections, wounds or several types of stress. The teliospores of the pathogenic filamentous fungus Sporisorium scitamineum produces smut disease in non- resistant varieties of sugarcane. Two HMMG from smut-resistant varieties of sugarcane promote teliospore chemotaxis and agglutination, respectively. However, HMMG from by non-resistant varieties do not promote teliospore aggregation. Agglutination is a lectin- dependent response from the HMMG endowed with arginase activity that also inhibits teliospore germination. Conversely, dispersal of teliospore aggregates and loss of chemotaxis are induced by other glycoproteins from resistant cultivars after prolonged contact with the chemoattractant. This is accompanied by disassembly of the cell wall protoplast leakage, which is caused by hydrolytic enzymes, such as chitinase and β-1,4- and β-1,3-glucanases. In this report, we describe agglutination as a “bait and kill” mechanism that congregates as many pathogenic organisms in a specific region to be killed by the action of a second, concerted hydrolytic switch.

Inflammation Thread Runs across Medical Laboratory Specialities

We work on the assumption that four major specialities or sectors of medical laboratory assays, comprising clinical chemistry, haematology, immunology, and microbiology, embraced by genome sequencing techniques, are routinely in use. Medical laboratory markers for inflammation serve as model: they are allotted to most fields of medical lab assays including genomics. Incessant coding of assays aligns each of them in the long lists of big data. As exemplified with the complement gene family, containing C2, C3, C8A, C8B, CFH, CFI, and ITGB2, heritability patterns/risk factors associated with diseases with genetic glitch of complement components are unfolding. The C4 component serum levels depend on sufficient vitamin D whilst low vitamin D is inversely related to IgG1, IgA, and C3 linking vitamin sufficiency to innate immunity. Whole genome sequencing of microbial organisms may distinguish virulent from nonvirulent and antibiotic resistant from nonresistant varieties of the same species and thus can be listed in personal big data banks including microbiological pathology; the big data warehouse continues to grow.

GENOTYPIC DIFFERENCES IN THE GROWTH OF BANANAS (MUSA SPP.) INFECTED WITH MIGRATORY ENDOPARASITIC NEMATODES. 1. ROOTS

The effects of nematodes on root morphology and the association of root characteristics with resistance to nematodes of seven banana varieties were investigated in two experiments. Banana plants were grown in controlled conditions within polytunnels and harvested on three occasions for the measurement of root morphology and biomass. Varieties differed in their resistance to nematodes, from resistant (Yg Km5, FHIA 17, FHIA 03) and partly resistant (FHIA 01, FHIA 25) to not resistant ((FHIA 23, Williams). Nematodes reduced the root dry weight of FHIA 01, FHIA 17 and FHIA 23 at some harvests. Primary root number was on average 9.5% lower in nematode-infected plants than controls, with no differences among the varieties. Thus, there was no simple association between the resistance of these varieties and their tolerance to nematodes. Varieties differed in root morphology. Root dry weight was greatest for resistant varieties Yg Km5 and FHIA 03, and least for non-resistant varieties FHIA 23 and Williams. Thus, resistance to nematodes was associated with varieties with greater root mass and more and larger primary roots.

Severity of powdery mildew on spring barley in the Czech Republicin 1971-2000

Results of scoring the resistance to powdery mildew of 127 spring barley varieties that were gradually included in 923 official variety trials were analysed. The resistance of a variety was defined by the level of infection by the disease. Therefore, the data can be used to assess the disease severity. Several characteristics indicative of disease severity were considered, including the disease severity coefficient (= average infection of non-resistant varieties in trials with a high disease severity/the proportion of such trials). The value of the coefficient is inversely proportional to disease severity. According to the coefficient the highest powdery mildew severity occurred in 1988, 1972 and 1995, and during the period 1971–1975. This is confirmed by results of some other characteristics, while that of further characteristics point to 1985–1989 as the period with the highest disease severity. The lowest disease severity was found in 1982 and 1977 and for the period 1976–1980. High disease severity was found every year in 9–75% (on average in 33%) of the trials. The characteristics of disease severity as well as the effects of widely grown and susceptible varieties of winter barley on the increase in inoculum potential and, as a consequence, on faster adaptation of the pathogen to resistance of spring barley, especially that conditioned by gene Mla13, are discussed.  

A century of plant virus management in the Salinas Valley of California, ‘East of Eden’

The mild climate of the Salinas Valley, CA lends itself well to a diverse agricultural industry. However, the diversity of weeds, crops and insect and fungal vectors also provide favorable conditions for plant virus disease development. This paper considers the incidence and management of several plant viruses that have caused serious epidemics and been significant in the agricultural development of the Salinas Valley during the 20th century. Beet curly top virus (BCTV) almost destroyed the newly established sugarbeet industry soon after its establishment in the 1870s. A combination of resistant varieties, cultural management of beet crops to provide early plant emergence and development, and a highly coordinated beet leafhopper vector scouting and spray programme have achieved adequate control of BCTV. These programmes were first developed by the USDA and still operate. Lettuce mosaic virus was first recognized as causing a serious disease of lettuce crops in the 1930s. The virus is still a threat but it is controlled by a lettuce-free period in December and a seed certification programme that allows only seed lots with less than one infected seed in 30 000 to be grown. ‘Virus Yellows’ is a term used to describe a complex of yellows inducing viruses which affect mainly sugarbeet and lettuce. These viruses include Beet yellows virus and Beet western yellows virus. During the 1950s, the complex caused significant yield losses to susceptible crops in the Salinas Valley. A beet-free period was introduced and is still used for control. The fungus-borne rhizomania disease of sugarbeet caused by Beet necrotic yellow vein virus was first detected in Salinas Valley in 1983. Assumed to have been introduced from Europe, this virus has now become widespread in California wherever beets are grown and crop losses can be as high as 100%. Movement of infested soil and beets accounts for its spread throughout the beet-growing regions of the United States. Control of rhizomania involves several cultural practices, but the use of resistant varieties is the most effective and is necessary where soils are infested. Rhizomania-resistant varieties are now available that perform almost as well as the non-resistant varieties under non-rhizomania conditions. Another soil-borne disease termed lettuce dieback, caused by a tomato bushy stunt-like tombusvirus, has become economically limiting to romaine and leaf lettuce varieties. The virus has no known vector and it seems to be moved through infested soil and water. Heavy rains in the past 4 years have caused flooding of the Salinas River and lettuce fields along the river have been affected severely by dieback. Studies are now in progress to characterize this new virus and identify sources of resistance. Agriculture in the Salinas Valley continues to grow and diversify, driven by demands for ‘clean’, high quality food by the American public and for export. The major aspects of plant virus control, including crop-free periods, breeding for resistance, elimination of inoculum sources, and vector control will continue to be vital to this expansion. Undoubtedly, the advances in crop production through genetic manipulation and advances in pest management through biological control will eventually become an important part of agricultural improvement.

Effect of organic amendments on the growth and chemical composition of tomato, eggplant and chilli and their susceptibility to attack byMeloidogyne incognita

Fewer larvae ofMeloidogyne incognita invaded and fewer galls were formed when seedlings of nonresistant varieties of tomato, eggplant and chilli were growing in soil to which oilcakes of mahua, castor, neem/margosa, mustard and groundnut had been added. Chemical analysis of plant tissue showed that, compared with untreated plants, plants growing in treated soil contained greater concentrations of phenols and frequently of amino acids, proteins and carbohydrates.

Evaluation of Various Bird-Resistant and Non-Resistant Varieties of Grain Sorghum for Use in Broiler Diets

The use of grain sorghums in poultry diets has increased greatly during the past few years. Consumption of the grain in the field by wild birds is a major problem and has prompted the development of several bird-resistant varieties, the majority of these being brown seeded. The fact that bird resistance is attributed to the grain's tannin content has caused concern regarding the efficacy of its use in poultry diets.Chang and Fuller (1964) reported that growth depressions resulting from the feeding of high-tannin grain sorghums were similiar to those produced by equivalent levels of tannic acid. The feeding of grain sorghums high in tannin content resulted in significantly lower body weights, but feed consumption was not decreased. Therefore, it was believed that true tannin toxicity had been demonstrated. Supplementing diets containing grain sorghums of high and low tannin content with twice the normal supplemental levels of choline and methionine .

The sorghum midge, Contarinia sorghicola (Coq.), in Nigeria

The sorghum midge, <i>Contarinia sorghicola</i> (Coq.), in Nigeria

The control of the micro-climate for given practical purposes

Experiments carried out at the Central Agricultural Meteorological Observatory show that it is possible to lower or raise the temperature of the soil surface quite appreciable by covering with a layer of chalk powder or charcoal powder respectively. A thin cover of vegetation further lowers the soil temperature. It is also noted that a thin layer of chalk can bring about an appreciable reduction of evaporation from the soil. Experiments in ‘orchard heating’ indicate the possibility of minimizing frost damage by controlling air temperature during cold waves.&#x0D; &#x0D; A brief account is also given of a micro-climatic test for drought resistance by subjecting two lots of plants to the conditions in two artificially produced environments, viz., one in which air is hot and dry and another in which the air is kept cool and humid within an enclosure of wet screens. It is found that plants which are drought-resistant have a control on transpiration while non-resistant types do not indicated such control. By comparing the transpiration ratio with the evaporation ratio it is possible to identify the resistant from the non-resistant varieties. It takes about one week per lot of plants, to complete the above test.

STUDIES ON DROUGHT RESISTANCE IN SPRING WHEAT

The results of a number of preliminary investigations regarding the nature of drought resistance in wheat are presented.A study of the susceptibility of wheat plants to drought at different stages of development showed that the shooting and the soft-dough periods were the most critical, from the point of view of grain yield. Heavy foliage losses occurred when plants were exposed during the shooting period, and recovery was very slow. Exposure of plants during the stooling stage resulted generally in transient injury, as the capacity for recovery was particularly great at this time. Plants subjected to drought during the hard-dough stage sacrificed little in kernel plumpness.Hardening of wheat plants by soil drought, or by limited exposures to atmospheric drought, increased their resistance to exposures of severe atmospheric drought.The drought-resistant varieties Milturum and Caesium were found to possess a more highly branched primary root system than the non-resistant varieties Marquis and Reward. The durum varieties, Pentad and Pelissier, were found to excel in numbers of primary roots produced, having an average of five per plant. Milturum, Caesium and Baart had more than four primary roots per plant on the average; while Canus, Federation, Reward, Marquis, Garnet and Red Bobs No. 222 had from 3.2 to 3.6. Reliance wheat and wild oats had not more than three primary roots per plant.The addition of superphosphate to the soil resulted in a slight decrease in number of primary roots of Milturum, Caesium and Marquis, and a slight increase in the number of Reward.The kernels of the drought-resistant varieties, Milturum and Caesium, did not show any marked superiority to those of Marquis, Reward, Garnet and Red Bobs No. 222, in capacity to germinate in the more concentrated solutions of sodium chloride, potassium chloride and sucrose. A higher energy of germination was displayed by the kernels of Milturum, Caesium and Garnet than by those of the other three varieties tested.Milturum and Canus exhibited high resistance to injury from windburn when tested m the late stooling to early shooting growth stages. The durum varieties Pentad and Kubanka and the soft wheat, Baart, on the other hand, showed high susceptibility. The soft wheat, Federation, and the variety Red Bobs No. 222 were moderately susceptible.