Genetic variation of seedling traits responded to brassinosteroid and gibberellin inhibitors in maize (Zea mays) doubled haploid lines

The purpose of this study was to examine the genotypic variation in maize doubled haploid (DH) lines response to brassinosteroid and gibberellin inhibitors. Plant responses to hormone inhibitors were determined in growth chamber experiments using germination paper for three different seedling treatments: application of propiconazole (Pcz), uniconazole (Ucz) or water (control). Mesocotyl length (ML) was more sensitive to hormone inhibitors, especially to the Ucz treatment, than other seedling traits. ML was significantly correlated with other traits in the Ucz treatment. All the seedling traits showed moderate-to-high broad sense heritability values, ranging from 0.39 to 0.82. The Euclidian genetic distances of inbred line pairs ranged from 1.27 to 19.94, indicating there was a high level of variability across the maize DH lines used in this study. DH lines with extreme MLs were identified, which can provide valuable breeding resources for improving abiotic stress tolerance, and for further genetic studies.     

A Simple Device to Prepare Single Ears of Spelt (Triticum spelta L.) for Seeding with the "Seedmatic-System"

Spelt is usually planted as spikelets. These cannot be obtained by the threshing machines generally used for bread wheat. With a simple device it is possible to separate single ears of spelt into spikelets ready for sowing. At the same time, it is possible to score the fragility of the rachis and the degree of free thresh-ability, both important characteristics for the selection of spelt.     

Root colonisation by arbuscular mycorrhizal, fine endophytic and dark septate fungi across a pH gradient in acid beech forests

Colonisation by root endophytes can be beneficial to plants growing on acid, nutrient-poor soils. Arbuscular mycorrhizal (AM) fungi can supply herbs with nutrients and may give protection against aluminium toxicity. Two other root colonising fungi, fine endophytes (FE) and dark septate fungi (DSE), are less well known but are potentially of benefit to their host plant. AM fungi are the most prevalent symbionts in herbs at neutral to acidic soil pH. At extremely low pH, fungal growth can be limited and AM colonisation is usually rare. Fine and dark septate endophytes, on the other hand, have been observed more often under these conditions. In order to relate endophyte colonisation to a gradient in soil pH, we investigated root colonisation by AM, FE and DSE in Maianthemum bifolium, Galium odoratum, Mercurialis perennis and Stellaria nemorum, from a range of acidic beech forests. With decreasing pH, colonisation by AM decreased, whereas the other two endophytes increased. AM and FE colonisation were inversely correlated in Maianthemum bifolium. We compared changes in root colonisation with those in chemical composition of soil and leaf samples and found a positive correlation between leaf magnesium concentrations and the presence of DSE in Galium odoratum. Aluminium concentration in Maianthemum bifolium tended to be lower when FE colonisation was high, suggesting a possible role for the fungi in plant protection against Al. We suggest that FE and DSE may replace AM fungi in herbaceous vegetation at extremely low pH, counteracting some of the negative effects of high soil acidity on plants.     

Effect of harvesting and drying conditions on chlorophyll levels of soybean (Glycine max L. Merr)

Chlorophyll in soybean represents a downgrading factor for the crops. Five Brazilian cultivars were harvested between R(6) and R(8) stage of development (Fehr & Caviness scale) and dried at 25 degrees and 40 degrees C. The effect of maturity stages and two drying conditions after harvest were studied to achieve reduction of moisture and chlorophylls to acceptable levels. When seeds were dried at 25 degrees C, even harvesting at early stages of development such as R(6), the green pigments were almost degraded, and 16 ppm of chlorophyll were found at maximum, accompanied by loss of moisture. Moisture and chlorophyll declines as seed matures, but at intermediary stages (R(6)-R(7)), chlorophyll degrades first, so the rate of moisture loss should not be used to predict chlorophyll contents. At 40 degrees C, complete degradation of chlorophyll pigments is only achieved when seeds are swathed from R(7) stage up, otherwise the seed quality could be compromised. Slow drying allows almost complete removal of green pigments, even when seeds are swathed a few days before the physiological maturity stage.     

Prüfung vonAegilops-Arten auf Resistenz gegenPseudocercosporella herpotrichoides (Fron) Deighton

Zusammenfassung 490 Sippen von 21Aegilops-Arten wurden in den Jahren 1980 bis 1982 unter Freilandbedingungen mit künstlicher Infektion auf Resistenz gegenüber dem Erreger der Halmbruchkrankheit des Getreides,Pseudocercosporella herpotrichoides (Fron) Deighton geprüft. Außerdem erfolgte an ausgewählten Sippen die Prüfung der Jungpflanzenanfälligkeit im Phytotron. Unter denAegilops-Mustern erwiesen sich im Freiland 31 Herkünfte als resistent bzw. schwach anfällig. Im einzelnen handelte es sich um Vertreter der ArtenAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa undAe. tauschii. Die im Jungpflanzenstadium geprüften 7 Sippen, 3 vonAe. ventricosa und je 1 vonAe. bicornis, Ae. kotschyi undAe. lorentii, waren ebenfalls resistent bzw. schwach anfällig.

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TestingAegilops species for their reaction toPseudocercosporella herpotrichoides (Fron) Deighton

Summary From 1980–1982 490 accessions out of 21Aegilops species were tested in a field trial with artificial infection regarding their resistance toPseudocercosporella herpotrichoides (Fron) Deighton in cereal crops. Simultaneously, selected accessions were checked for their susceptibility in the seedling stage under controlled conditions in the phytotrone. Among theAegilops samples 31 accessions proved to be resistant or only slightly susceptible. This refers toAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa andAe. tauschii. The accessions checked in the seedling stage, i. e. 3 ofAe. ventricosa and 1 ofAe. bicornis, Ae. kotschyi andAe. lorentii, showed also resistance or only low susceptibility.

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Aegilops Pseudocercosporella herpotrichoides

1980–1982 . 490 21 Aegilops Pseudocercosporella herpotrichoides (Fron) Deighton. , . Aegilops 31 ; ¶rt; Ae. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa, Ae. tauschii. , , Ae. ventricosa Ae. bicornis, Ae. kotschyi, Ae. lorentii .

     

Differentiation between lutein monoester regioisomers and detection of lutein diesters from marigold flowers (Tagetes erecta L.) and several fruits by liquid chromatography-mass spectrometry.

Liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCIMS) was employed for the identification of eight lutein monoesters, formed by incomplete enzymatic saponification of lutein diesters of marigold (Tagetes erecta L.) by Candida rugosa lipase. Additionally, the main lutein diesters naturally occurring in marigold oleoresin were chromatographically separated and identified. The LC-MS method allows for characterization of lutein diesters occurring as minor components in several fruits; this was demonstrated by analysis of extracts of cape gooseberry (Physalis peruviana L.), kiwano (Cucumis metuliferus E. Mey. ex Naud.), and pumpkin (Cucurbita pepo L.). The assignment of the regioisomers of lutein monoesters is based on the characteristic fragmentation pattern: the most intense daughter ion generally results from the loss of the substituent (fatty acid or hydroxyl group) bound to the epsilon-ionone ring, yielding an allylic cation. The limit of detection was estimated at 0.5 microg/mL with lutein dimyristate as reference compound. This method provides a useful tool to obtain further insight into the biochemical reactions leading to lutein ester formation in plants.