CONTRIBUTION OF INDUCED MUTATION

Mutation breeding for crop improvement is a technique used for over 70 years. It is a fast way to increase the rate of spontaneous genetic variation in plants contributing to global food security. The genetic variability, created through mutagenesis i.e. physical or chemical, is an important breeding material for developing improved varieties and many studies in the field of functional genomics. The randomly generated heritable genetic changes are expressed in the mutant plants, which are selected for new and useful traits, such as high yielding, disease resistance, tolerance to abiotic stresses and improved nutritional quality. The technique helps to improve the tolerance of crop species to adverse climatic conditions, such as extremes of temperatures, drought, occurrence of pests and diseases. Through support provided by the Joint FAO/IAEA Division, significant agronomic and economic impact has been generated in many countries. The FAO/IAEA Mutant Variety Database (MVD) (http://mvd.iaea.org) demonstrates the significance of mutation induction as an efficient tool in crop improvement. The extensive use of induced mutant germplasms in crop improvement programmes resulted in releasing of more than 3,332 mutant varieties from around 228 crop species (20 July 2020)

Genetic diversity in sodium azide induced wheat mutants studied by ssr markers

Mutationsinduced artificially way are one of the tools used to increase genetic variation in populations where genetic variation has been shrinking especially due to various reasons one of which is domestication. In this study, Simple Sequence Repeats (SSRs) markers were used to screen genetic diversity in sodium azide (NaN3) induced fourteen fourth-generation advanced wheat mutant lines. The mean values of polymorphism rate (29.44%), polymorphic information content (PIC; 0.82), marker index (MI; 1.95) and resolving power (Rp; 1.31) were calculated according to SSR marker profiles. Two SSRs, Xwmc170 and Xcfd6, were detected as the most polymorphic markers, Xgwm626 proved the highest PIC and MI values, and Xcfd6 gave the highest Rp value. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram classified 15 plants into four groups. The Principle Component Analysis (PCA) showed 88.9% of the total genetic variation. The results obtained in the present study might be useful for determining the efficiency of NaN3 for creating mutant wheat lines with enough genetic variability to implement wheat-breeding programs as germplasm resources.Yapay yolla indüklenen mutasyonlar, genetik varyasyonun özellikle ıslah gibi çeşitli nedenlerden dolayı küçüldüğü popülasyonlarda, çeşitliliği arttıran araçlardan biridir. Bu çalışmada, sodyum azid (NaN3) kullanılarak indüklenen on dört dördüncü jenerasyon ileri mutant buğday hatlarında, genetik çeşitliliği taramak için Basit Dizi Tekrarları (SSR) belirteçleri kullanıldı. SSR belirteç profillerine göre ortalama polimorfizm oranı (% 29,44), polimorfik bilgi içeriği (PIC; 0,82), belirteç indeksi (Mİ; 1,95) ve belirteç çözünürlük gücü (Rp; 1,31) hesaplandı. İki SSR belirteci, Xwmc170 ve Xcfd6, en yüksek polimorfizm oranına sahip belirteçler olarak tespit edildi. Xgwm626 en yüksek PIC ve Mİ değerlerini, Xcfd6 de en yüksek Rp değerini verdi. Ağırlıksız Çift-Grup Yöntemi ile Aritmetik Ortalama (UPGMA) dendrogramı 15 bitkiyi dört gruba ayırdı. Temel Bileşenler Analizi (PCA) toplam genetik varyasyonun % 88,9'unu gösterdi. Bu çalışma, buğday ıslah programlarında genetik kaynak olarak kullanılmak üzere yeterli genetik çeşitliliğe sahip mutant buğday hatlarını oluşturmak için sodyum azitin etkinliğinin gösterilmesi hususunda yararlı olabilir

Obtaining candidate salt tolerant wheat mutant lines derived from combination of sodium azide mutagenesis and somatic embryogenesis

Plant mutants are important bio-resources for crop breeding and functional gene studies. In the present study, conventional chemical mutagenesis technique was combined with somatic embryogenesis to obtain candidate salt tolerant mutant wheat lines. For this purpose, 0-5 mM Sodium Azide (NaN3) was applied for 30 minutes to embryonic calli under in vitro conditions to produce genetic variations in the bread wheat (Triticum aestivum L. cv. Adana 99). Treated and non-treated calli were put in somatic embryo induction media, and 3 and 4 mM NaN3 were determined as optimum mutation doses for somatic embryo induction. The obtained somatic embryos from these optimum mutagen doses were then screened for tolerance in regeneration media containing 125 mM NaCl to be used to improve tolerance to salt stress. In NaN3 treatment, 14 mutants with moderate salt tolerance were obtained. The results suggest that the in vitro technique in combination with chemical mutagenesis may be a useful approach for accelerating breeding strategies to create enough genetic variation in populations and to get fourth generation putative salt tolerant wheat mutant lines in less than 1.5 years.Bitki mutantları, bitki ıslahı ve fonksiyonel gen çalışmaları için önemli biyo-kaynaklardır. Mevcut çalışmada, tuza toleranslı aday mutant buğday hatları elde etmek için somatik embriyogenez ile konvansiyonel kimyasal mutajenez tekniği birleştirildi. Bu amaçla; ekmeklik buğdayda (Triticum aestivum L. cv. Adana 99) genetik varyasyonlar yaratmak için embriyonik kalluslara 0-5 mM Sodyum Azid (NaN3), 30 dakika boyunca in vitro ortamda uygulandı. İşlem görmüş ve görmemiş kalluslar, somatik embriyo teşvik ortamına konularak somatik embriyo teşviki için 3 ve 4 mM NaN3 uygulaması optimum mutasyon dozları olarak tespit edildi. Ardından bu mutasyon dozları ile muamele edilen kalluslardan elde edilen somatik embriyolar tuz stresine tolerans geliştirmek için kullanılacak 125 mM NaCl içeren rejenerasyon ortamlarında tolerans açısından tarandı. NaN3 muamelesinde, orta düzeyde tuza toleransı olan 14 mutant elde edildi. Elde edilen sonuçlar; kimyasal mutagenez ile kombine halde in vitro teknik uygulamasının, popülasyonlarda yeterli genetik varyasyon oluşturmak ve 1.5 yıldan daha az bir sürede dördüncü jenerasyon tuz toleranslı aday buğday mutant hatlarını ıslah sürecini hızlandırarak elde etmek için kullanışlı bir yöntem olabileceğini göstermektedir

Mutant Resources of Spring Wheat to Improve Grain Quality and Morphology

The objective of this study was to broaden genetic variation of spring common wheat, evaluate and identify among M5 mutant lines those with high-yield and improved grain quality characteristics. New lines were generated by initial treatment of variety of Eritrospermum-35 adapted to conditions of Kazakhstan by irradiation with 100-Gy and 200-Gy doses from a 60Co source. Yield-associated traits including grain number and weight per main spike, grain weight (GW) per plant, and the thousand-kernel weight; grain size and grain shape variations; as well as quality characteristics such as grain protein content (GPC), iron, and zinc concentrations were evaluated. Mutant lines with high iron and zinc concentrations and high protein content were identified as those which have 1.6–3.4 and 1.4–2.9 times more as well as 3.7–16.9% more higher data of target concentrations than parental variety had, respectively. Several mutant lines showed significant increase in both grain iron and zinc concentrations. The positive correlation of grain quality parameters with grain area, length, and width suggest that they are related to each other. Wheat grain can be biofortified with micronutrients without negative impact on crop productivity using new mutant lines. Mutation breeding can significantly contribute to human health malnutrition and improve nutrition quality diet

Heat stress-induced changes in shoot and root characteristics of genotypes of tepary bean ('Phaseolus acutifolius' A. Gray), common bean ('Phaseolus vulgaris' L.) and their interspecific lines

Heat stress is a major limitation to grain yield in common bean (Phaseolus vulgaris L.). Tepary bean (Phaseolus acutifolius A. Gray) is better adapted to heat stress than common bean. Ten tepary bean accessions, four common bean genotypes and four interspecific lines involving P. vulgaris and P. acutufolius, P. coccineus and P. dumosus were evaluated for tolerance to heat stress conditions induced under greenhouse conditions and these were compared to plants grown under ambient temperatures. The high temperature treatment was 29 ±5 °C during the day and was >24 °C (up to 27 °C) during the night, while the ambient temperature (AT) treatment was 25 ±5 °C during the day and 19± 2 °C at night. The genotypic differences were evaluated for morphophysiological characteristics of shoot and root and also yield components. The Genotype and Genotype × Temperature interactions were significant for all shoot and root morpho-physiological characteristics evaluated. Higher temperature (HT) significantly affected leaf photosynthetic efficiency, total chlorophyll content, and stomatal conductance. The effect was positive or negative, depending on the genotypes. Tepary accessions showed reduced total chlorophyll content, while common bean genotypes and the interspecific lines were less affected. Tepary accessions also showed reduced stomatal conductance, but increased leaf photosynthetic efficiency under HT. Common bean genotypes increased stomatal conductance and decreased leaf photosynthetic efficiency. High temperature decreased total root length, specific root length and pod biomass compared to ambient conditions, but there was no marked effect on pollen viability of the tested genotypes. The superior adaptation of tepary germplasm accessions to high temperature is attributed to their ability to regulate stomatal opening and photosynthetic efficiency, together with a superior ability to remobilize photosynthates from older leaves to pods during physiological maturity

Mutation breeding for heat and drought tolerance in tepary bean (Phaseolus acutifolius A. Gray)

Tepary bean (Phaseolus acutifolius A. Gray) is more heat and drought tolerant than common bean (P. vulgaris L.). Four hundred mutant lines of two tepary accessions (G40068 and G40159) were generated by ethyl methane sulfonate (EMS) treatment. In preliminary studies of the M5 mutant lines under abiotic stress, three mutant lines (CMT 38, CMT 109, CMT 187) were selected from six mutated lines based on morpho-physiological traits and superior yield and advanced to the M6 generation. The M6 mutant lines were uniform and genetically stable. These mutant lines and their original (M0) parents were evaluated for heat and drought tolerance under greenhouse conditions. Their performance was evaluated for morpho-physiological attributes, seed yield and yield components. Under high temperature and drought conditions, the CMT 38 mutant (M6 line) and its original tepary (M0) accession (G40068) showed greater values of pod biomass, pod number and 100-seed biomass than the other lines tested. The CMT 109 and CMT 187 mutant lines and their G40159 original accession (M0) also showed the highest value of seed number under high temperature and drought conditions. This suggests that the previous screening performed during the population advancement of these mutant lines, based on morphological traits like growth habit, was not detrimental to the yield variables evaluated here. Under combined heat and drought conditions, different parameters could be incorporated into tepary breeding programmes, as selection criteria to screen genotypes for tolerance to heat and drought stress. These parameters included: chlorophyll (SPAD) readings, seed biomass, 100-seed biomass and seed number because they explain the observed variance in the principal component analysis. Two additional traits (root biomass and stem diameter) were also identified as useful attributes, based on univariate analysis. The mutant lines evaluated here offer potential for further improvement of tepary bean to high temperature and drought

Organ-specific expression of genes involved in iron homeostasis in wheat mutant lines with increased grain iron and zinc content

Background Iron deficiency is a well-known nutritional disorder, and the imbalance of trace-elements, specifically iron, is the most common nutrient deficiency of foods across the world, including in Kazakhstan. Wheat has significant nutritional relevance, especially in the provision of iron, however many bread wheat varieties have low iron despite the need for human nourishment. In this study, the expression profiles of wheat homologous genes related to iron homeostasis were investigated. The work resulted in the development of two new M5 mutant lines of spring bread wheat through gamma-irradiation (200 Gy) with higher grain iron and zinc content, lower phytic acid content, and enhanced iron bioavailability compared to the parent variety. Mutant lines were also characterized by higher means of yield associated traits such as grain number per main spike, grain weight per main spike, grain weight per plant, and thousand-grain weight. Methods The homologous genes of bread wheat from several groups were selected for gene expression studies exploring the tight control of iron uptake, translocation rate and accumulation in leaves and roots, and comprised the following: (1) S-adenosylmethionine synthase (SAMS), nicotianamine synthase (NAS1), nicotianamine aminotransferase (NAAT), deoxymugineic acid synthetase (DMAS), involved in the synthesis and release of phytosiderophores; (2) transcription factor basic helix-loop-helix (bHLH); (3) transporters of mugineic acid (TOM), involved in long-distance iron transport; (4) yellow stripe-like (YSlA), and the vacuolar transporter (VIT2), involved in intracellular iron transport and storage; and lastly (5) natural resistance-associated macrophage protein (NRAMP) and ferritin (Fer1A). Results The wheat homologous genes TaSAMS, TaNAS1, and TaDMAS, were significantly up-regulated in the roots of both mutant lines by 2.1–4.7-fold compared to the parent variety. The combined over-expression of TaYSlA and TaVIT2 was also revealed in the roots of mutant lines by 1.3–2.7-fold. In one of the mutant lines, genes encoding intracellular iron transport and storage genes TaNRAMP and TaFer1A-D showed significant up-regulation in roots and leaves (by 1.4- and 3.5-fold, respectively). The highest expression was recorded in the transcription factor TabHLH, which was expressed 13.1- and 30.2-fold in the roots of mutant lines. Our research revealed that genotype-dependent and organ-specific gene expression profiles can provide new insights into iron uptake, translocation rate, storage, and regulation in wheat which aid the prioritization of gene targets for iron biofortification and bioavailability

Diagnostic Value of White Blood Cell and C-Reactive Protein in Pediatric Appendicitis

Background. Acute appendicitis (AA) associated with acute phase reaction is the most prevalent disease which requires emergency surgery. Its delayed diagnosis and unnecessarily performed appendectomies lead to numerous complications. In our study, we aimed to detect the role of WBC and CRP in the exclusion of acute and complicated appendicitis and diagnostic accuracy in pediatric age group. Methods. Appendectomized patient groups were constructed based on the results of histological evaluation. The area under a receiver operating characteristic (ROC) curve (AUC) was performed to examine diagnostic accuracy. Results. When WBC and CRP were used in combination, based on cut-off values of ≥13.1 × 103/μL for WBC counts and ≥1.17 mg/dL for CRP level, diagnostic parameters were as follows: sensitivity, 98.7%; specificity, 71.3%; PPV, 50.6%; NPV, 99.5%; diagnostic accuracy, 77.6%; LR(+), 3.44; LR(−), 0.017. AUC values were 0.845 (95% CI 0.800–0.891) for WBC and 0.887 (95% CI 0.841–0.932) for CRP. Conclusions. For complicated appendicitis, CRP has the highest degree of diagnostic accuracy. The diagnosis of appendicitis should be made primarily based on clinical examination, and obviously more specific and systemic inflammatory markers are needed. Combined use of cut-off values of WBC (≥13100/μL) and CRP (≥1.17 mg/L) yields a higher sensitivity and NPV for the diagnosis of complicated appendicitis

Detection and characterization of novel polymorphisms using SSR and ISSR markers in sodium azide-induced salt tolerant wheat mutants

Salinity is one of the major abiotic constraints affecting crop production in dry-land and irrigated areas of the world. Reducing the spread of salinization and/or increasing the salt tolerance of high-yielding crops, are important global issues. Induced-mutagenesis is a powerful tool for crop improvement and it has been applied for the past 80 years to produce new mutant varieties in both seed and vegetatively propagated crops. Chemical mutagen, like sodium azide, frequently use for inducing genetic variability in plants. It creates point mutation and damages in chromosomes, so enhance tolerance in the plants for numerous adverse conditions. In this study, genetic variation increased through the application of chemical mutagens to somatic embryos for selecting salt-tolerant wheat mutants and characterization of them using molecular markers. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND licens

Sensitivity of watermelon variety Bojura to mutant agents 60Co and EMS

A study on the sensitivity of watermelon variety Bojura to mutagenic agents was carried out in 2013-2014. The goal was to establish effective doses for mutagenic treatment of dry seeds with 60Co gamma rays (80, 100, 200, 250, 350 and 450 Gy) and swollen seeds with water for 24 hours were treated with ethyl methanesulfonate (EMS) at a concentration of 2%. Dominant mutations were not observed in the M1 generation. Morphological changes in 14 of 1395 M2 plants were observed. Phenotypic variations changes were the colour of the seed coat, chlorophyll disorders of cotyledons, leaves, petals, and alterations of the location of the fruit set in the central stem. Visible changes of the morphological characteristics of the fruit were not observed. The doses induced certain morphological changes, however, higher doses or combined gamma rays 60Co and EMS treatments would induce mutations more efficiently. Subsequent experiments are required to obtain mutants with changes that affect flowers and fruits. The results are important for increasing mutation efficiency in watermelon breeding