A gabona levéltetvek hatása a búza sütőipari minőségére = Effect of cereal aphids on the baking quality of wheat flour

Szárbaindulás kezdetén történt drótkeretre feszített vektorháló anyaggal a 10-12 hajtást tartalmazó búzacsomók izolálása. Az izolátorok kihelyezését követően Diuraphis noxia, Rhopalosiphum padi, Sitobion avenae 5-5 szárnyatlan imágó egyedével történt a növények mesterséges levéltetű fertőzése. A puhaszemű Mv 17 fajta kalászhossza, kalászonkénti szemszáma, kalászonkénti szemtömege és a szemek átlagos tömege szignifikánsan csökkent kalászos hajtásonként 2-3 S. avenae táplálkozása következtében. A búzaliszt SE HPLC-vel meghatározott gliadin, glutenin és összes fehérje tartalma szignifikánsan nőtt a levéltetvek kártétele következtében. A gliadin és glutenin tartalom eltérő növekedése szignifikáns gliadin/glutenin arány csökkenést eredményezett, mely a sütőipari minőség egyik legfontosabb mutatója. A keményszemű Mv Magvas és Mv Magdaléna búza fajták kalászhossza és kalászonkénti szemszáma az utolsó év kivételével nem változott a levéltetű fertőzés hatására. A nagy egyedszámú D. noxia szignifikáns kalászonkénti szemtömeg és átlagos szemtömeg csökkenést eredményezett mindkét fajtán. A jóval kisebb egyedszámú S. avenae táplálkozása ugyanezt eredményezte. A keményszemű búza fajták gliadin, glutenin és összes fehérje tartalma szignifikánsan nőtt a levéltetvek táplálkozása következtében, de a gliadin/glutenin arány nem csökkent. A két keményszemű fajta gliadin, glutenin és összes fehérje tartalma valamint gliadin/glutenin aránya szignifikánsan különbözött. | Wheat plants (T. aestivum L; soft cultivar Mv 17; hard cultvs. Mv Magdaléna, Mv Magvas) were caged at the beginning of stem elongation (providing various isolation levels) and later artificially infected with respective aphid species (indigenous sp. M. dirhodum, S. avenae, R. padi; invasive sp. D. noxia). During development aphid number assessment was performed to correlate quantitative and qualitative results. Flours from grains of infected plants were analyzed for gluten proteins(glutenins, gliadins governing bread-making quality), albumins+globulins content by SE-HPLC. In Mv 17 cultv. both the glutenin and gliadin content was significantly higher in the seeds harvested from aphid infected plants. The gliadin/glutenin ratio was significantly lower in wheat flour prepared from infected plants than in from uninfected control. The most remarkable decrease in gliadin/glutenin ratio was caused by M. dirhodum, D. noxia, S. avenae infection followed by R. padi at high-abundance and low-abundance, respectively. Quality parameters of flour from hard kernel types are different. Feeding does not induce significant reduction in the gliadin, total protein content and gliadin/glutenin ratio. The glutenin content of cultv. Mv Magvas was significantly reduced by lower number of aphids, regardless of the species. Both quantitative and qualitative characters of the flours are significantly affected by plant sucking aphids in case of soft and less significantly in hard kernel cultvs

Az új növénytermesztési rendszerek környezetbiotechnológiai kérdései = Environmental biotechnology aspects of the new crop production systems

Kukorica monokultúrában a Glomus-fajok a domináns mykorrhiza gombák, függetlenül a tápanyag utánpótlás szintjétől. Az alcsoportok közül a Glomus-Ad fajok a legérzékenyebbek a trágyázásra. A hagyományos és a GMO kukoricanövényeket egyformán kolonizálják a mykorrhiza gombák, de mindkét növénycsoport mentes volt kórokozó Fusarium-fajoktól. A párosodási típus gének (MAT) aszexuális gombákban is működnek. A MAT transzkripciós faktor számos olyan génre is hat, így egy HOG-típusú MAPkinázra, egy nitrilázra és a white collar komplex génjeire, amelyeknek nincs szerepük az ivaros szaporodásban. Járványos körülmények között női sterilitás épül fel bizonyos gombák populációiban, s ez fajon belüli szegregációhoz vezet, amint azt a kukoricapatogén Fusarium subglutinans Európai populációjában lehetett tapasztalni. Új, kriptikus funkciójú mitokondriális plazmid (pFP1) jelent meg a Fusarium proliferatumban. Virusellenálló burgonyafajtákat állítottunk elő, marker mentes transzformációval és megállapítottuk a transzgén stabil beépülését. A rezisztencia tartósnak bizonyult és számos PVY törzzsel szemben mutattak általános védettséget, melyet hibrid vírus törzsekkel is ellenőriztünk. A bioenergia termelésre tervezett kukorica és akác kultúrák vírusbetegségeinek molekuláris térképezésével azok járványtani jelentőségére kaptunk fontos adatokat. Kidolgoztuk a transzgén kromoszóma szintű azonosításának lehetőségét is burgonya vonalainkban. | In corn monoculture, the Glomus clade was the predominant mycorrhiza fungus group irrespective of mineral fertilization practices. Of the subgroups, Glomus-Ad species were the most sensitive to fertilization. GMO and non-GMO plants were equally colonized by mycorrhiza fungi, but they were free of pathogenic Fusarium species. Mating type genes (MAT) are active in asexually reproducing fungi. Functional analysis of a variety of genes, including a HOG-type MAPK gene, a putative nitrilase gene, and genes of the white collar complex indicates that the MAT transcription factors affect a number of genes not directly involved in sexual reproduction. Female sterility is gradually built up during epidemic conditions in local populations of fungi leading to within species segregation as demonstrated in a pan-European population of the maize rot pathogen, Fusarium sublutinans. A novel mitochondrial plasmid, pFP1 with cryptic phenotype has been identified in Fusarium proliferatum. Virus resistant transgenic potato varieties were engineered with marker free construct and the stable integration of the transgene was confirmed. The resistance proved to be durable and expressed against several potato virus Y strains, which characteristic phenomenon was checked with hybrid viruses, too. Molecular analysis of the Peanut Stunt Virus and Maize Dwarf Mosaic Virus resulted important epidemiological data of those cultures expected to be cultivated for bioenergy

Environment and Genotype Effects on the Content of Dietary Fiber and Its Components in Wheat in the HEALTHGRAIN Diversity Screen

Within the HEALTHGRAIN diversity screen, the variability of the contents of dietary fiber (DF) and components thereof was studied in wheat. Furthermore, the contribution of genotype and environment to this variability was estimated. The levels of total DF (TDF), total nonstarch polysaccharide (TOTNSP), water-extractable nonstarch polysaccharide (WENSP), total arabinoxylan (TOTAX), lignin, and beta-glucan in whole meal, flour, and/or bran varied similar to 1.8-fold. The highest variability was observed for the water-extractable arabinoxylan (WEAX) level in flour and bran (similar to 3.7-fold). Genotype and environment contributed to a similar extent to the variability in TDF, TOTNSP, and TOTAX content in wheat. The observed relatively high impact of genotype-environment interaction suggests that the levels of these constituents are weak breeding parameters. The WENSP level is a more stable parameter as the effect of the interaction term was much less than the impact of genotype. For TOTAX and WEAX in flour, WEAX in bran, beta-glucan in whole meal, and extract viscosity, wheat genotype determined similar to 50% or higher of the variation observed, whereas the impact of the genotype environment interaction was relatively low. These findings suggest that the health-related and technological functionality of wheat can be directed to a certain extent by selection of appropriate wheat varieties.status: publishe

Genotype and Environment Effects on the Contents of Vitamins B1, B2, B3,and B6 in Wheat Grain

The total contents of thiamine (vitamin B1), riboflavin (B2), and pyridoxine (B6) and the bioavailable forms of niacin (B3) were determined on wholemeal flours of 24 winter wheat varieties grown on four sites (United Kingdom, Poland, France, and Hungary) in 2007 and of two spring varieties grown on the same sites with the exception of Poland. The contents of vitamins B1 (5.53-13.55 mu g/g dw), B2 (0.77-1.40 mu g/g dw), and B6 (1.27-2.97 mu g/g dw) were within the ranges reported previously, while the content of bioavailable vitamin B3 (0.16-1.74 mu g/g dw) was about 10-15% of the total contents of vitamin B3 reported in previous studies. Strong correlations were observed between the contents of vitamins B1, B3, and B6, and partitioning of the variance in the contents of these three B vitamins showed that between 48 and 70% was accounted for by the environment. By contrast, the content of vitamin B2 was not correlated with the contents of other B vitamins, and 73% of the variance was ascribed to the error term, which suggests that this trait may be influenced by genotype x environment interactions. Whereas the contents of vitamins B1, B3, and B6 were correlated positively with the mean temperature from heading to harvest (r > 0.8), the content of vitamin B2 was positively correlated with precipitation during the 3 months prior to heading. These results are discussed in relation to the development of new wheat varieties with enhanced health benefits

Variation in the Content of Dietary Fiber and Components Thereof in Wheats in the HEALTHGRAIN Diversity Screen

Within the HEALTHGRAIN diversity screening program, the variation in the content of dietary fiber and components thereof in different types of wheat was studied. The wheat types were winter (131 varieties) and spring (20 varieties) wheats (both Triticum aestivum L., also referred to as common wheats), durum wheat (Triticum durum Desf., 10 varieties), spelt wheat (Triticum spelta L., 5 varieties), einkorn wheat (T. monococcum L., 5 varieties), and emmer wheat (Triticum dicoccum Schubler, 5 varieties). Common wheats contained, on average, the highest level of dietary fiber [11.5-18.3% of dry matter (dm)], whereas einkorn and emmer wheats contained the lowest level (7.2-12.8% of dm). Intermediate levels were measured in durum and spelt wheats (10.7-15.5% of dm). Also, on the basis of the arabinoxylan levels in bran, the different wheat types could be divided this way, with ranges of 12.7-22.1% of dm for common wheats, 6.1-14.4% of dm for einkorn and emmer wheats, and 10.9-13.9% of dm for durum and spelt wheats. On average, bran arabinoxylan made up ca. 29% of the total dietary fiber content of wheat. In contrast to what was the case for bran, the arabinoxylan levels in flour were comparable between the different types of wheat. For wheat, in general, they varied between 1.35 and 2.75% of dm. Einkorn, emmer, and durum wheats contained about half the level of mixed-linkage beta-glucan (0.25-0.45% of dm) present in winter, spring, and spelt wheats (0.50-0.95% of dm). All wheat types had Klason lignin, the levels of which varied from 1.40 to 3.25% of dm. The arabinoxylan contents in bran and the dietary fiber contents in wholemeal were inversely and positively related with bran yield, respectively. Aqueous wholemeal extract viscosity, a measure for the level of soluble dietary fiber, was determined to large extent by the level of water-extractable arabinoxylan. In conclusion, the present study revealed substantial variation in the contents of dietary fiber and constituents thereof between different wheat types and varieties.status: publishe

愛知教育大学 教育創造開発機構

One hundred and fifty bread wheat lines and 50 other lines of small-grain cereals (spelt, durum wheat, Triticum monococcum, Triticum dicoccum, oats, rye, and barley) were selected for diversity in their geographical origin, age, and characteristics. They were grown on a single site in Hungary in 2004−2005, harvested, milled, and analyzed for a range of phytochemicals (tocols, sterols, phenolic acids, folates, alkylresorcinols) and fiber components that are considered to have health benefits. Detailed analyses of these components in the different species are reported in a series of accompanying papers. The present paper discusses the comparative levels of the bioactive components in the different species, showing differences in both ranges and mean amounts. Furthermore, detailed comparisons of the bread wheat lines show that it is possible to identify lines in which high levels of phytochemicals and dietary fiber components are combined with good yield and processing quality. This means that commercially competitive lines with high levels of bioactive components are a realistic goal for plant breeders

Mutation discovery for crop improvement

Increasing crop yields to ensure food security is a major challenge. Mutagenesis is an important tool in crop improvement and is free of the regulatory restrictions imposed on genetically modified organisms. The forward genetic approach enables the identification of improved or novel phenotypes that can be exploited in conventional breeding programmes. Powerful reverse genetic strategies that allow the detection of induced point mutations in individuals of the mutagenized populations can address the major challenge of linking sequence information to the biological function of genes and can also identify novel variation for plant breeding. This review briefly discusses recent advances in the detection of mutants and the potential of mutagenesis for crop improvement. The Author [2009]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved

Phytochemicals and Dietary Fiber Components in Rye Varieties in the HEALTHGRAIN Diversity Screen

Ten rye varieties grown in one location were analyzed for their contents of dietary fiber (arabinoxylan and beta-glucan) and phytochemicals (folate, tocols, phenolic acids, alkylresorcinols, and sterols). The varieties included old and modern varieties from five European countries. Significant differences were observed in the contents of all phytochemicals in whole grains and in the fiber contents in the flour and bran. The old French varieties Haute Loire and Queyras had high contents of most phytochemicals, whereas the Polish varieties Dankowskie-Zlote and Warko were relatively poor in phytochemicals. The varieties with a high content of folate tended to have low alkylresorcinol contents and vice versa. Furthermore, high contents of arabinoxylans were associated with high contents in tocols and sterols. The 10 selected rye samples comprising old populations and old and modern varieties from different ecological regions of Europe demonstrate high natural variation in their composition and show that landraces and old populations are useful genetic resources for plant breeding. The contents of single phytochemicals can likely be affected by breeding, and they may be adjusted by the right selection of genotype.status: publishe

Phytochemical and Fiber Components in Oat Varieties in the HEALTHGRAIN Diversity Screen

The levels and compositions of a range of phytochemicals (sterols, tocols, avenanthramides, folates, phenolic acids) and dietary fiber components were determined in five oat cultivars (four husked and one naked) grown on a single site in 2005. The total levels of tocols, phenolic acids, and avenanthramides varied by over 2-fold between cultivars, but less variation occurred in total sterols and total folates. Limited variation was also observed in the dietary fiber content and composition of the four husked lines. These results indicate that it may be possible to selectively breed for lines with high contents of dietary fiber and specific groups of phytochemicals.status: publishe