Otpornost novosadskih sorti pšenice prema fuzariozi klasa u prirodnim uslovima zaraze

Fusarium head blight caused by Fusarium graminearum is a very destructive pathogen and can cause significant losses in yield by total or partial destruction of grain. One of the main ways of control this pathogen is growing resistant varieties. Resistance to F. graminearum was examined on 26 NS wheat varieties in natural conditions of infection, determining the percentage of Fusarium damaged kernels. The loss in weight of wheat kernels due to infection by F. graminearum was determined on the basis of the difference in 1000 kernel weight of healthy kernels and 1000 kernel weight in which were located Fusarium damaged kernels. The percentage of Fusarium damaged kernels was ranged from 1-18.3%. The largest percentage of infected kernels in field conditions had durum wheat varieties Dušan (18.3%) and Durumko (17%). The facultative variety Nevesinjka had 17% Fusarium damaged kernels. The lowest percentage of Fusarium damaged kernels had varieties Zlatka and Sofija (1.3%). Reducing in the 1000 kernel weight was noticed in all the studied varieties and was ranged from 1.6 to 15.1%. Between the percentage of Fusarium damaged kernels and loss in weight of wheat kernels was found a significant correlation (0,59). .Prouzrokovač fuzarioze klasa (Fusarium graminearum) je veoma destruktivan patogen i može prouzrokovati značajne gubitke u prinosu, potpunom ili delimičnom destrukcijom zrna. Jedan od osnovnih načina njegovog suzbijanja je gajenje otpornih genotipova. Otpornost prema fuzariozi klasa ispitivana je na 26 novosadskih sorti pšenice u uslovima prirodne zaraze, na osnovu procenta zaraženih zrna. Gubitak u masi zrna izračunat je na osnovu razlike između mase 1000 zdravih i mase 1000 zrna među kojima su bila i fuzariozna. U uslovima prirodne zaraze, procenat fuzarioznih zrna kretao se od 1-18.3%. Najveći procenat zaraženih zrna bio je kod sorti durum pšenice Dušan (18.3%) i Durumko (17%). Fakultativna sorta Nevesinjka imala je 17% zaraženih zrna. Najniži procenat fuzarioznih zrna imale su sorte Zlatka i Sofija (1.3%). Smanjenje mase 1000 zrna uočeno je kod svih ispitivanih sorti i kretalo se od 1.6 do 15.1%. Između procenta fuzarioznih zrna i gubitaka u masi 1000 zrna utvrđena je značajna korelacija (0,59).

Prisustvo deoksinivalenola u uzorcima strnih žita u žetvenoj 2009/10. godini

Fusarium head blight (FHB) is present in all growing regions of small grains and causes significant losses in yield and grain quality. In our environmental conditions, dominant species is Fusarium graminearum Group 2. During 2009/10 there was a significant Fusarium infestation on wheat, barley and triticale. The aim of this study was to examine the contents of deoxynivalenol (DON) in cereal samples taken after 2009/10 harvest season. We analyzed 22 NS varieties of small grains from Rimski Šančevi, including 16 varieties of winter wheat, one facultative wheat variety, four varieties of winter barley and one variety of triticale. Analytical methods based on clean-up by solid-phase extraction (SPE) columns and detection by liquid chromatography were used. Fifteen out the 22 analyzed samples were positive for the presence of DON at a mean level of 0.537 mg/kg. The highest concentration was 1.952 mg/kg. These findings were in correlation with percentage of the Fusarium damaged kernels.Patogeni iz roda Fusarium su prisutni u svim rejonima gajenja strnih žita i nanose značajne gubitke u prinosu i kvalitetu zrna. Fuzariozu klasa pšenice prouzrokuje veći broj vrsta iz roda Fusarium. U našim uslovima gajenja dominantna je vrsta Fusarium graminearum Grupa 2. U toku 2009/10. godine došlo je do značajne pojave fuzarioza na pšenici, ječmu i tritikaleu. Cilj rada je bio da se ispita sadržaj DON-a na uzorcima strnih žita uzetih posle žetve iz uslova prirodne zaraze. Analizirane su 22 novosadske sorte strnih žita iz lokaliteta Rimski Šančevi, od čega: 16 sorti ozime pšenice, jedna fakultativna sorta pšenice, četiri sorte ozimog ječma i jedna sorta tritikalea. Uzorci su uzeti sa parcela različitih površina u zavisnosti od značaja i rasprostranjenosti gajene sorte. Analitičko određivanje je zasnovano na prečišćavanju sirovog ekstrakta analiziranih uzoraka pomoću tzv. Mucosep kolona, a zatim je sadržaj DON-a kvantitativno određen tečnom hromatografijom. Od 22 analizirana uzorka strnih žita čak 15 (68,2%) je bilo pozitivno na prisustvo DON-a. Još veći procenat zaraženosti DON-om je utvrđen kada je u pitanju samo pšenica (82,4%). Prosečan sadržaj DON-a je iznosio 0,537 mg/kg a najveća koncentracija je utvrđena u uzorku tritikalea i iznosila je visokih 1,952 mg/kg. Od svih uzoraka koji su bili pozitivni na prisustvo ovog mikotoksina, 2 su prevazilazila koncentracije koje su propisane od strane Evropske komisije. Sve ovo ukazuje na visoku zaraženost strnih žita sa naših polja iz žetve 2010. Procenat fuzarioznih zrna kod 16 ispitivanih sorti pšenice kretao se od 1 do 11,5%, a gubici u masi 1000 zrna od 1,2 do 5,7%. Između jačine zaraze u polju i sadržaja mikotoksina DON ustanovljena je potpuna pozitivna korelacija kod pojedinih sorti. Fakultativna sorta pšenice Nataša je imala visoku koncentraciju DON od 1,572 mg/kg, pri stepenu zaraze u polju od 33,3% zaraženih klasova po 1 m2. Sorta Zvezdana imala je najniži procenat zaraze u polju od 1% i kod nje nije determinisano prisustvo mikotoksina DON

Latent period and infection frequency as components of partial resistance to powdery mildew in some winter wheat varieties

Partial resistance to powdery mildew (Blumeria graminis f.sp. tritici) of 20 winter wheat varieties and a susceptible control variety Barbee was tested under controlled conditions. To asses the varieties for partial resistance, latent period (LP 50) and infection frequency (number of colonies per unit leaf area) were used. The variety Dragana showed the highest degree of partial resistance that involved a long latent period and low infection frequency. The varieties Angelina, Barbara and NS 27 /03 had a somewhat shorter LP 50, but a similar infection frequency; therefore, it seems likely that they also possess a high degree of partial resistance. Significantly high negative correlations were found between LP 50 and infection frequency (r= - 0.755)

Uzroci smanjenja prinosa strnih žita u 2010. godini

During the 2009/10. there was a significant decrease in the grain yield of wheat, barley and triticale, regardless of whether it's winter or spring time of sowing. Large amounts of precipitation, replacements of warm and cold periods during April, May and June were significantly favored pathogens of small grains, first of all causes of powdery mildews, leaf rust, leaf spots and Fusarium head blight. At lower fields, where the water is kept for a long period of time, there was lodging of plants due to the appearance of pathogens that cause root and foot rot. Percentage of Fusarium damaged kernels on some fields in the production ranged up to 33.3% per 1m2 (Natasha variety in spring time of sowing). However, in the collection of genotypes originating from different countries of the world, out of 461 genotypes, only seven or 1.5% had percentage of Fusarium damaged kernels over 5%. The largest number of genotypes, 381 or 82.6% had 0-1% of infected ears per 1m2.U toku 2009/10. godine došlo je do značajnog smanjenja prinosa na pšenici, ječmu i tritikaleu, bez obzira da li se radi o ozimom ili jarom roku setve. Velike količine padavina, smenjivanje toplih i hladnih perioda tokom aprila, maja i juna značajno su favorizovali patogene strnih žita, pre svih prouzrokovače pepelnice, lisne rđe, pegavosti lista i fuzarioze klasa. Na nižim terenima, gde se voda dugo zadržavala, došlo je do propadanja biljaka, usled pojave velikog broja patogena koji prouzrokuju trulež korena i prizemnog dela stabla. Procenat fuzarioznih klasova na nekim parcelama u proizvodnji kretao se i do 33,3% po 1m2 (sorta Nataša u jarom roku setve). Međutim, u kolekciji genotipova koji potiču iz različitih država sveta, od 461 genotipa, kod svega sedam ili 1,5% je procenat fuzarioznih klasova iznosio preko 5%. Najveći broj genotipova, 381 ili 82,6% imao je 0-1% zaraženih klasova po 1m2

Uticaj klimatskih promena na patogene ratarsko povrtarskih biljaka - mere adaptacije i suzbijanje

The risk of disease and pest damages to agricultural crops has increased significantly as a result of climatic changes. Climate change could have positive, negative or no impact on field and vegetable crops diseases. However, it can be foreseen that in some regions, under very strong temperature-precipitation change 'signal', losses induced by increased infection potential of present and/or new diseases could be significant. The paper includes analysis of the severity of diseases caused by parasitic fungi in small grains, sunflower, sugar beet, potato and tomato. Climatic changes have resulted in the dominance of pathogens that require higher temperatures for their development or are better able to adapt to drought conditions. This is the reason why small grains fungal diseases of the genus Fusarium and Septoria spp. have dominant role, causing significant damage. Because the causal agents of sunflower spots develop very well and rapidly at high temperatures, global warming has caused these diseases to become more severe in Serbia and the damages they cause have increased. Furthermore, today, due to increased temperatures, the successful control of the Cercospora leaf spot requires twice as many chemical treatments as in the previous period. Until recently, one to two treatments (1.5 on average) during the growing season were needed in order to control C. beticola, whereas today two to four treatments are required. The early blight of tomato and potato has in recent years become a major disease and has been causing significant damages in these two crops. The increasing severity is attributed to the increase in temperature and the greater frequency of years having warm and dry summers.U radu su razmotreni odnosi biljke i patogena pod uticajem klimatskih promena. Analizirana je zastupljenost patogena na strnim žitima, suncokretu, šećernoj repi, krompiru i paradajzu i dati su temperaturni okviri za njihovu pojavu u jačem intenzitetu. Na osnovu toga predložene su mere adaptacije i suzbijanja. Sistem predviđanja i izveštavanja o pojavi patogena na određenom području imaće veoma važnu ulogu u savremenim sistemima proizvodnje i racionalne primene mera suzbijanja