Seed quality of ZP maize inbred lines of different maturity groups and genetic background

U radu su sprovedena ispitivanja kvaliteta semena samooplodnih linija kukuruza stvorenih u Institutu za kukuruz „Zemun Polje“ razliĉitih grupa zrenja i genetiĉke osnove. U laboratorijskim i poljskim uslovima utvrĊena je klijavost i vigor semena iz 2011. nakon ĉetiri godine ĉuvanja u kontrolisanim uslovima (18 °C i 60% RH) i semena iz 2014. nakon godinu dana ĉuvanja na 5 °C i 60% RH. Cilj je bio utvrditi tolerantnost odabranih linija na niske temperature prilikom klijanja i nicanja, dugoveĉnost semena u kontrolisanim uslovima ĉuvanja, genetiĉku divergentnost linija primenom proteinskih markera i proceniti uticaj genetiĉke osnove na kvalitet semena. U laboratoriji za ispitivanje semena praćeni su sledeći parametri kvaliteta: vitalnost, klijavost, energija klijanja, dužina klijanaca, vigor ispitan tetrazolium testom, hladnim testom, testom ubrzanog starenja, testom pojave primarnog korena i testom provodljivosti. Primenom vigor testova na semenu dva nivoa starosti omogućena je bolja klasifikacija linija u pogledu kvaliteta, nego standardnim testom klijavosti. Rezultati rada ukazuju da su hladni test i test ubrzanog starenja najpogodniji za procenu vigora semena u laboratoriji, s tim da je hladni test bolji pokazatelj nicanja u polju. Ispitivane samooplodne linije pokazale su dobru sposobnost oĉuvanja kvaliteta semena kao i visok nivo toleratnosti na niske temperature u toku klijanja i ranog porasta biljaka. Kontrolisani uslovi ĉuvanja na 18 °C omogućili su da se klijavost i vigor semena u ispitivanom periodu, održi na visokom nivou. Dužina vegetacije samooplodnih linija nije imala znaĉajan uticaj na klijavost i vigor semena. Kvalitet semena ispitivanih samooplodnih linija je prvenstveno bio pod uticajem genetiĉke osnove. Linije poreklom od Lancaster populacije imale su slabiji vigor u odnosu na linije BSSS i Iowa Dent porekla. U radu je potvrĊeno da vigor testovi imaju važnu ulogu u ispitivanju kvaliteta semena samooplodnih linija kukuruza. Dobijeni rezultati direktno se mogu iskoristiti u oplemenjivaĉkim programima u cilju poboljšanja klijavosti i vigora semena. Ostvareni rezultati ukazuju da su informacije o genetiĉkom poreklu samooplodnih linija važan indikator vigora semena. Pored podataka o genetiĉkom poreklu linija veliki znaĉaj ima karakterizacija putem biohemijskih markera.The extensive seed quality evaluations of maize inbred lines developed at the Maize Research Institute Zemun Polje of different maturity groups and genetic background were conducted. In laboratory and field conditions germination and vigour of seed produced in 2011 and 2014 was determined, after four years of storage at 18 °C, 60% RH and one year of storage at 5 °C, 60% RH, respectively. The objective of this research was to determine the chilling tolerance of selected inbred lines during germination and emergence, seed longevity under controlled storage conditions, genetic divergence determined by biochemical markers and to assess the impact of the genetic background on seed quality. Following seed quality parameters were tested: viability, germination, seedling length and vigour examined by cold test, accelerated ageing test, tetrazolium test, radicle emergence test and conductivity test. Vigour tests provided a better classification of inbred lines of different seed age in terms of quality than standard germination test. Obtained results show that cold test and accelerated aging test are the most suitable for assessing seed vigour in the laboratory, but cold test is a better indicator of field emergence. Tested maize inbred lines showed good seed storability and high level of chilling tolerance during germination and early growth of plants. Controlled storage conditions at 18 °C, have enabled that germination and seed vigor remains at the high level in the examined period. Seed germination and vigour of maize inbred lines were not affected by length of vegetation. Seed quality was primarily influenced by genetic background of tested inbred lines. Inbred lines originating from Lancaster populations had lower vigour compared to lines with BSSS and Iowa Dent origin. This research confirmed that vigor tests play an important role in seed quality testing of maize inbred lines. Results of this work can be directly used in breeding programs to improve germination and seed vigour. Achieved results indicate that information about the genetic origin of inbred lines is an important indicator of seed vigour. Finally, data emphasized the importance of inbred line characterization by biochemical markers in addition to genetic origin information

Comparison of tetrazolium, exised embryo and standard germination test at fruit and forest tree seeds

The tetrazolium test, (TTZ), is a fundamental method for quality testing of fruit and forest tree seeds. Results obtained by TTZ test could be in two days compared to the standard germination test that results could be in four monts. Obtaining these results quickly is extremely significant in short deadlines for seed export and import. The TTZ test provides the values of potential germination. Values of standard germination will achieve its potential if there are no any obstacle for germination (seed dormancy). The aim of this paper was to determine the differences between potential and standard germination in vineyard peach, cherry plum, false acacia, Austrian pine, common spruce and wild apple. The test were conducted according to ISTA Rules (2003). The results were statistically analised and significant differences between potential and standard germination were detected in vineyard peach, false acacia and common spruce. An excised embryo test (EET) is also recommended by the ISTA Rules for some species. This test allow increase the speed germination by eliminating the seed coat structures. It was applied in peach, cherry plum and wild apple. Results that are got by EET test were not differ significantly from the potential and standard germination unless for vineyard peach. Results that are got it by TTZ test show heihger values to standard germination when seed is dormancy and infected. In those situation EET test could be a good alternative.Tetrazolium (TTZ) test predstavlja osnovni metod za ispitivanje kvaliteta voćarskih i šumskih vrsta. Brzo dobijanje rezultata TTZ testom (2 dana) u odnosu na test klijavosti (i do 4 meseca) izuzetno je značajno zbog kratkih rokova pri uvozu i izvozu semena. Tetrazolium test daje vrednosti potencijalne klijavosti. Vrednosti standardne klijavosti će dostići taj potencijal ukoliko nema nikakvih prepreka za klijanje (npr. mirovanje semena). Cilj ovog rada bio je utvrđivanje razlika između potencijalne i standardne klijavosti kod vinogradarske breskve, džanarike, bagrema, crnog bora, smrče i jabuke. Rezultati su statistički obrađeni i utvrđeno je da postoje značajne razlike između vrednosti potencijalne i standardne klijavosti kod ispitivanog uzorka vinogradarske breskve, bagrema i smrče. ISTA pravila za neke biljne vrste preporučuju i test izdvojenog embriona (EET). Ovim testom ubrzava se klijanje uklanjanjem spoljašnjih struktura semena. EET test je primenjen kod breskve, džanarike i divlje jabuke. Dobijene vrednosti EET testa nisu se statistički značajno razlikovale od vrednosti potencijalne i standardne klijavosti, osim kod vinogradarske breskve. Rezultati TTZ testa pokazuju veće vrednosti u odnosu na standardnu klijavost kada je seme dormantno i zaraženo patogenima. U takvim slučajevima EET test može biti dobra alternativa

Current Opportunities for Targeting Dysregulated Neurodevelopmental Signaling Pathways in Glioblastoma

Glioblastoma (GBM) is the most common and highly lethal type of brain tumor, with poor survival despite advances in understanding its complexity. After current standard therapeutic treatment, including tumor resection, radiotherapy and concomitant chemotherapy with temozolomide, the median overall survival of patients with this type of tumor is less than 15 months. Thus, there is an urgent need for new insights into GBM molecular characteristics and progress in targeted therapy in order to improve clinical outcomes. The literature data revealed that a number of different signaling pathways are dysregulated in GBM. In this review, we intended to summarize and discuss current literature data and therapeutic modalities focused on targeting dysregulated signaling pathways in GBM. A better understanding of opportunities for targeting signaling pathways that influences malignant behavior of GBM cells might open the way for the development of novel GBM-targeted therapies

Izmene ISTA pravila za ispitivanje klijavosti semena na početku 21. veka

The International Seed Testing Association (ISTA) was established in 1924 with the idea of standardization in seed testing worldwide. The first international rules for seed testing (ISTA Rules) were published in 1931. The development of ISTA Rules is constant. ISTA members are involved in the ongoing process of developing methods for seed sampling and testing. The methods are validated to ensure that test procedures provide reliable and reproducible results. Since 2001, ISTA Rules have been issued annually. ISTA accredited laboratories have to work according to valid ISTA Rules. In this paper, ISTA Rules changes in seed germination testing since 2001 were presented. Changes in testing methods, criteria for seedling evaluation, procedure of calculation and reporting of results are presented in detail. It can be concluded that the amendments to the ISTA Rules are necessary in order to harmonize seed testing and modern trends in seed trade.Među narodna organizacija za ispitivanje semena (ISTA) je osnovana 1924. godine sa idejom ujednačavanja procesa ispitivanja semena širom sveta. Prva međunarodna pravila za ispitivanje semena (ISTA Pravila) su objavljena 1931. godine. Razvoj ISTA Pravila je konstantan. ISTA članice su uključene u stalan proces razvoja metoda za uzorkovanje i ispitivanje semena. Metode prolaze kroz odgovarajuće ispitivanje validnosti kako bi se obezbedilo da procedure testova daju pouzdane i ponovljive rezultate. Od 2001. godine izdaju se nova ISTA Pravila svake godine. ISTA akreditovane laboratorije imaju obavezu da svoj sistem kvaliteta i svoj rad usaglase sa važećim ISTA Pravilima. U ovom radu prikazane su izmene ISTA Pravila u oblasti ispitivanja klijavosti semena od 2001. godine kao najvažnijeg parametra kvaliteta za promet semena. Pregled izmena ISTA Pravila je sproveden korišćenjem štampanih i elektronskih izdanja. U analizi su takođe korišćeni dokumenti sa ISTA godišnjih sastanaka u kojima su data objašnjenja za predložene izmene. Analizom je ustanovljeno da su u prethodnih 18 godina uvedene brojne izmene u ISTA Pravila za oblast ispitivanja klijavosti. Metode klijavosti za trinaest novih vrsta je uvedeno u Pravila, nekoliko metoda je izmenjeno, dozvoljena je upotreba novih substrata za naklijavanje kao i kombinacija substrata. Novi tipovi nenormalnosti su dodati i za određene vrste su izmenjeni kriterijumi za ocenu klijavosti. Za veliki broj pravila su data dodatna objašnjenja. Najvažnije izmene pravila su doprinele da procesispitivanja klijavosti semena postane brži i jednostavniji što je neophodno radi usklađivanja načina ispitivanja i savremenih tokova u prometu semena

SOX transcription factors and glioma stem cells: Choosing between stemness and differentiation

Glioblastoma (GBM) is the most common, most aggressive and deadliest brain tumor. Recently, remarkable progress has been made towards understanding the cellular and molecular biology of gliomas. GBM tumor initiation, progression and relapse as well as resistance to treatments are associated with glioma stem cells (GSCs). GSCs exhibit a high proliferation rate and self-renewal capacity and the ability to differentiate into diverse cell types, generating a range of distinct cell types within the tumor, leading to cellular heterogeneity. GBM tumors may contain different subsets of GSCs, and some of them may adopt a quiescent state that protects them against chemotherapy and radiotherapy. GSCs enriched in recurrent gliomas acquire more aggressive and therapy-resistant properties, making them more malignant, able to rapidly spread. The impact of SOX transcription factors (TFs) on brain tumors has been extensively studied in the last decade. Almost all SOX genes are expressed in GBM, and their expression levels are associated with patient prognosis and survival. Numerous SOX TFs are involved in the maintenance of the stemness of GSCs or play a role in the initiation of GSC differentiation. The fine-tuning of SOX gene expression levels controls the balance between cell stemness and differentiation. Therefore, innovative therapies targeting SOX TFs are emerging as promising tools for combatting GBM. Combatting GBM has been a demanding and challenging goal for decades. The current therapeutic strategies have not yet provided a cure for GBM and have only resulted in a slight improvement in patient survival. Novel approaches will require the fine adjustment of multimodal therapeutic strategies that simultaneously target numerous hallmarks of cancer cells to win the battle against GBM

SOX18 Is a Novel Target Gene of Hedgehog Signaling in Cervical Carcinoma Cell Lines

Although there is much evidence showing functional relationship between Hedgehog pathway, in particular Sonic hedgehog, and SOX transcription factors during embryonic development, scarce data are available regarding their crosstalk in cancer cells. SOX18 protein plays an important role in promoting tumor angiogenesis and therefore emerged as a promising potential target in antiangiogenic tumor therapy. Recently it became evident that expression of SOX18 gene in tumors is not restricted to endothelium of accompanying blood and lymphatic vessels, but in tumor cells as well. In this paper we have identified human SOX18 gene as a novel target gene of Hedgehog signaling in cervical carcinoma cell lines. We have presented data showing that expression of SOX18 gene is regulated by GLI1 and GLI2 transcription factors, final effectors of Hedgehog signaling, and that modulation of Hedgehog signaling activity in considerably influence SOX18 expression. We consider important that Hedgehog pathway inhibitors reduced SOX18 expression, thus showing, for the first time, possibility for manipulationwith SOX18 gene expression. In addition, we analyzed the role of SOX18 in malignant potential of cervical carcinoma cell line, and showed that its overexpression has no influence on cells proliferation and viability, but substantially promotes migration and invasion of cells in vitro. Pro-migratory effect of SOX18 suggests its role in promoting malignant spreading, possibly in response to Hedgehog activation

Uticaj agrotehničkih mera na kvalitet semena italijanskog ljulja

Thousand-seed weight and total germination from the first production year and two seed harvests were measured in tetraploid Italian ryegrass (cv. Tetraflorum) to study variations in seed quality. Four-year field experiments were carried out (2002-2006) in western Serbia and Italian ryegrass was established with three row spacings (20, 40 and 60 cm), four seeding rates (5, 10, 15 and 20 kg ha-1) and using four spring nitrogen rates (0, 50, 100 and 150 kg ha-1). High seed quality was obtained, except for the first experimental year (2003) and the second seed harvests which yielded the seed of unsatisfactory quality and validity. Applied factors and treatments did not change seed quality significantly unlike environmental conditions of production years which had considerable influence on seed quality.Ispitivana je masa 1000 semena i ukupna klijavost tetraploidnog italijanskog ljulja (sorte Tetraflorum) iz prve proizvodne godine i dve semenske žetve radi utvrđivanja razlika u kvalitetu semena. Četvorogodišnji poljski eksperiment je izveden (2002-2006) u zapadnoj Srbiji i italijanski ljulj je zasnivan na 3 međuredna rastojanja (20, 40 i 60 cm), četiri setvene norme (5, 10, 15 i 20 kg ha-1) i primenom četiri doze prihrane azotom (0, 50, 100 i 150 kg ha-1). Ostvaren je visok kvalitet semena, izuzev prve godine ispitivanja (2003), a ostvarena je i druga semenska žetva sa semenom nezadovoljavajućeg kvaliteta i upotrebljivosti. Primenjeni faktori i nivoi ispitivanja nisu značajno menjali kvalitet semena za razliku od vremenskih uslova u proizvodnim godinama koji su značajno uticali na kvalitet semena

Differences in national and international seed testing rules

Razlike u pravilima za ispitivanje kvaliteta semena u domaćem prometu (Pravilnik o kvalitetu semena poljoprivrednog bilja Sl. SFRJ 47/1987) i izvozu (Međunarodna pravila za ispitivanje semena-ISTA pravila) razlog su prisustva nepodudarnosti u radu prilikom ispitivanja semena i tumačenja dobijenih rezultata. Kod pojedinih biljnih vrsta se koriste i drugačije metode ispitivanja, što dodatno može dovesti do različitih rezultata o kvalitetu jedne iste partije semena. Stoga je cilj ovog rada da se istaknu razlike koje postoje i ukaže na potrebu ujednačavanja nacionalnih i međunarodnih pravila za ispitivanje semena. Kroz ovaj pregledni rad prikazane su glavne razlike prilikom uzorkovanja i najčešćih metoda ispitivanja kvaliteta semena: čistoće, klijavosti, mase 1000 semena i sadržaja vlage. Takođe su prikazane i razlike u kontroli kvaliteta uslova ispitivanja na koje laboratorije koje imaju i nacionalnu i međunarodnu akreditaciju moraju da obrate pažnju. U međunarodna ISTA pravila za ispitivanje semena unose se promene svake godine, na inicijativu laboratorija članica, na osnovu novih istraživanja i iskustava iz laboratorija širom sveta. Harmonizacija nacionalnih i međunarodnih pravila za ispitivanje semena umnogome bi olakšala rad u laboratorijama i doprinela ujednačenijim kriterijumima za ispitivanje semena i iznošenje rezultata ispitivanja.Differences in the seed testing rules for domestic trade (Regulation on the quality of seeds of agricultural plants Sl. SFRJ 47/1987) and export (International rules for seed testing - ISTA rules) are the reason for the lack of consistency in the seed testing and the interpretation of the obtained results. For certain species, there are even different test methods, which can additionally lead to inconsistent test results of the same seed lot. Therefore, the objective of this paper is to highlight the differences that exist and point out the need to harmonize national and international rules for seed testing. Through this review, the main differences during sampling and the most common methods of seed testing are shown: purity, germination, 1000 seed weight and moisture content. Differences in the quality control of test conditions are also shown, which laboratories that have both, national and international accreditation, must pay attention to. International rules (ISTA) are changed every year, at the initiative of member laboratories, based on new research and experiences from laboratories around the world. Harmonization of national and international rules for seed testing would greatly facilitate work in laboratories and contribute to uniform criteria for seed testing and reporting of test results

Standardna klijavost i nicanje klijanaca samooplodnih linija kukuruza u različitim temperaturnim uslovima

Standard laboratory germination seed test provides information on seed performance under defined environmental conditions aiming to estimate field planting value. Purpose of this study was to compare results from the standard germination test with seedling emergence in different outside temperature conditions. Sowing was done in three periods during spring, in trays exposed to outside conditions. Data obtained showed that differences in the germination, detected in the standard laboratory test, were also confirmed in field conditions. Expression of these differences, however, was dependent on temperature conditions during different sowing periods. Low temperatures during the early sowing were more discriminative than later temperature increase which completely reduced differences detected in the standard germination test.Standardni test klijavosti pruža informacije o ponašanju semena u definisanim uslovima klijanja sa ciljem procene poljske setvene vrednosti. Svrha ovog istraživanja bila je poređenje rezultata standardnog testa klijavosti sa nicanjem klijanaca u polju pri različitim spoljašnjim temperaturnim uslovima. Setva je obavljena tokom tri vremenska perioda u proleće, u posudama izloženim spoljašnjim uslovima. Dobijeni rezultati su pokazali da su razlike u klijavosti, detektovane pomoću standardnog laboratorijskog testa, potvrđene i u sub-optimalnim spoljnim uslovima. Međutim, ispoljavanje ovih razlika zavisilo je od temperaturnih uslova tokom različitih setvenih perioda. Niske temperature u ranom periodu setve su bile diskriminativnije od kasnijeg porasta temperature koji je potpuno umanjio razlike detektovane u standardom testu klijavosti

Termodinamička karakterizacija klijanaca pšenice poreklom iz semena sa različitih parcela

Wheat germination could be affected by different factors, including location. Start growth of seedlings present the energy transformations and the seed substance conversion. The aim of the experiment was to examine differences in germination and growth of wheat seedlings, originating from five fields with similar characteristics, with application of thermodynamic parameters of free energy and entropy. Variations in energy and total germination of wheat seed was under 10%. After eight days of germination testing, the relation between root and shoot at level of fresh and dry matter was 1:1, while only at seedlings from one field it was 1:2 in fresh and 1.5:1 in dry matter. The present differences could be the consequence of the different energy using in seedling. Hydrolysis intensification based on spontaneous reactions and increased order in four days old seedlings could result in increased germination. On the other hand, variations in energetic potential, order degree and hydrolysis of seed substance may not take off biosynthetic reactions in root and shoot. Present data towards that variation in growth of seedlings originating from seeds from different fields could be mainly connected to variations in energy potential inputted by water, but not by synthesized substance. Minimal differences between the individual fields could affect quality of the produced seed material, what was particularly underlined by application of thermodynamic parameters as quality indicators.Brojni faktori utiču na klijavost semena pšenice, među koje spada i lokacija. Početni rast klijanaca predstavlja rezultat energetskih transformacija i konverzije semene supstance. Cilj ogleda je bio da se ispitaju razlike u klijavosti i razvoju klijanaca pšenice poreklom iz semena dobijenog sa pet različitih parcela (koje imaju slične osobine), uz primenu termodinamičkih parametara slobodne energije i entropije. Variranje u energiji klijanja i ukupnoj klijavosti semena pšenice nije bilo veće od 10%. Nakon osam dana od početka testiranja klijavosti kod većine klijanaca je odnos između korena i izdanka na nivou sveže i suve materije bio 1:1, dok je jedino kod klijanaca poreklom iz semena samo sa jedne parcele ovaj odnos na nivou sveže materije bio skoro 1:2, a na nivou suve materije 1,5:1. Navedene razlike mogu biti posledica različitog iskorišćenja energije od strane samog klijanca. Intenziviranje hidrolize, na bazi spontanih reakcija, kao i povećane uređenosti kod klijanaca starih četiri dana bi moglo da rezultira nešto većom ukupnom klijavošću. Sa druge strane, variranja u energetskom potencijalu, stepenu uređenosti sistema i hidrolizi semene supstance ne moraju da se odraze i na biosintetske reakcije u korenu i izdanku. Navedeni podaci upućuju da su variranja u rastu klijanaca poreklom iz semena sa različitih parcela uglavnom vezana za variranja energetskog potencijala koji je unet sa vodom, a ne i sintetisane supstance klijanaca. Minimalne razlike između pojedinačnih parcela mogu uticati na kvalitet proizvedenog semenskog materijala, što je posebno naglašeno primenom termodinamičkih parametra, kao pokazatelja kvaliteta