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Antifogging additives for greenhouse covers - effects on phytochemicals and nutritional quality of lettuce
Get PDFCorrection: Although every effort was made to ensure the accuracy of the information, an unintentional error was overlooked during the rigorous review process and incorrect data for Daily light integral (DLI) was printed in Tab. 1 of the published version from Jun 15, 2022. The authors sincerely apologize for any confusion or inconvenience caused by this oversight. The corrected data for Daily light integral (DLI) is published in the corrected version from June 12, 2023. The change does not affect other data in this article or its overall conclusions.
Antifogging additives are commercially used in greenhouse films to prevent water droplet formation on these films. This can increase light transmission, and thus, improve crop yield. However, the effect of polytunnels with antifogging additives on phytochemical content in lettuce (Lactuca sativa var. capitata ) is currently unclear. Here, polytunnels were chosen as a model to investigate the impact of antifogging additives in a completely randomized setting. Analysis by means of chromatographic methods coupled with mass spectrometry revealed a general influence of polytunnel cultivation compared to lettuces grown without a polytunnel on the content of phenolic compounds, photosynthetic pigments and fatty acids. The use of antifogging additives does not lead to significant differences in phenolic compounds and fatty acids. However, significant differences were observed for carotenoids and chlorophylls by both polytunnel cultivation and the use of antifogging additives. These differences probably occurred predominantly due to differences in light and temperature regimes related to polytunnel cultivation. Thus, due to polytunnels in general and the use of antifogging additives in particular, environmental conditions are created that impact valuable compounds and alter nutritional quality of crops
QTL mapping of resistance to two wheat rust fungi, Puccinia triticina Eriks. and Puccinia striiformis Westend. in a multiparental wheat (Triticum aestivum L.) population
No full textMit einer weltweiten Produktion von 766 Millionen Tonnen im Jahr 2019 ist Weizen die zweitwichtigste Getreideart der Welt, die ≥ 20 % des Kalorien- und Proteinbedarfs der menschlichen Ernährung deckt. Weizenroste wie Puccinia striiformis f. sp. tritici und Puccinia triticina, die Erreger des Weizengelb- bzw. des Weizenbraunrosts, gehören zu den wichtigsten pilzlichen Krankheitserregern im Weizen, die Ertrags- und Qualitätsverluste von bis zu 70 % verursachen können. Die Nutzung von resistenten Sorten ist der wirtschaftlich sicherste und umweltfreundlichste Ansatz zur Vermeidung von Ertragsverlusten und zur Sicherung der menschlichen Ernährung. Durch die kontinuierliche Entwicklung neuer Rassen des Gelb- und Braunrosts, die gegen wichtige Resistenzgene virulent sind, ergibt sich die Notwendigkeit nach neuen Resistenzquellen zu suchen. In den letzten Jahren ist die Identifizierung von QTL zur Grundlage gezielter Züchtungsansätze geworden, die darauf abzielen, ein erhöhtes und dauerhaftes Resistenzniveau in modernen Weizensorten zu erreichen. Darüber hinaus haben sich MAGIC Populationen als hilfreiches Instrument für die Durchführung solcher genetischen Studien erwiesen.
Im Rahmen dieser Arbeit wurde die Bayerische MAGIC-Weizenpopulation (BMWpop) genutzt, um Resistenz QTL gegen Weizenroste zu identifizieren. Dabei lag der Fokus auf dem Braun- und Gelbrost. Die Keimlingsresistenz wurde unter kontrollierten Umweltbedingungen mit Hilfe spezifischer Blattsegmenttests geprüft. Die Adultpflanzenresistenz wurde in mehrjährigen Feldversuchen an drei Standorten in Deutschland getestet. Im Anschluss wurden die phänotypischen Daten zusammen mit den genotypischen Daten des 15 K + 5 K Infinium® iSelect® Arrays, der 17.267 Einzelnukleotid-Polymorphismen (SNP) enthält, genutzt, um eine Simple-Intervallkartierung (SIM) für die Resistenz gegen Gelb- und Braunrost durchzuführen. Insgesamt wurden in unabhängigen SIM-Studien 19 QTL für Braunrostresistenz identifiziert, die 11 verschiedenen Regionen auf den Chromosomen 1A, 4A, 4D, 5A, 6B, 7A und 7D entsprechen. Sechs dieser Regionen könnten mutmaßlich neue QTL darstellen und wurden bisher nicht beschrieben. Für Gelbrost wurden 21 QTL entdeckt, die 13 verschiedenen chromosomalen Regionen entsprechen, von denen zwei möglicherweise bisher nicht bekannte QTL darstellen und sich auf den Weizenchromosomen 3D und 7D befinden. Die Peak-Marker der identifizierten QTL konnten teilweise direkt mit Genen annotiert werden, von denen bekannt ist, dass sie an der quantitativen Resistenz gegen Gelb- und Braunrost beteiligt sind. Zusätzliche vielversprechende Genannotationen im Zusammenhang mit Resistenzreaktionen wurden bei Betrachtung eines fixen Intervalls von ± 500 kb um jeden Peak-Marker eines QTLs identifiziert.
Die bayerische MAGIC-Weizenpopulation erwies sich für den Nachweis von Resistenz QTL gegen Gelb- und Braunrost als gut geeignet. Anhand der phänotypischen Reaktionen wurden RILs mit erhöhter Resistenz gegen beide Rostpilze identifiziert, die aufgrund ihrer Abstammung von Elite-Elternmaterial leicht in Zuchtprogramme integriert werden können.With a global production of 766 million tons in 2019, wheat is the world\u27s second most important cereal, providing ≥ 20 % of calories and protein for the human diet. Wheat rusts such as Puccinia striiformis f. sp. tritici and Puccinia triticina, the causal agents of stripe rust and leaf rust respectively, are among the most important fungal pathogens in wheat with the potential to cause severe yield and quality losses up to 70 %. Use of resistant cultivars is the economically safest and most environmentally friendly approach to avoid yield losses and ensure food security. However, the continuous development of new races of stripe rust and leaf rust that are virulent against important resistance genes increases the need for new sources of resistance. In recent years, the identification of quantitative trait loci (QTL) has become the basis of targeted breeding approaches aiming at increased and durable resistance in modern wheat cultivars. In addition, multiparent advanced generation intercross (MAGIC) populations have proven to be a powerful tool to carry out such genetic studies.
In the framework of this thesis, the Bavarian MAGIC wheat population (BMWpop) was used to detect QTL conferring resistance against leaf rust and stripe rust. Seedling resistance was screened under controlled environmental conditions by using a detached leaf assay. Adult plant resistance was tested in multi-year’s field trials at three locations in Germany. Phenotypic data, together with genotypic data from the 15 K + 5 K Infinium® iSelect® array containing 17,267 single nucleotide polymorphisms (SNP), were used to perform simple interval mapping (SIM) for stripe rust and leaf rust resistance. In total, 19 QTL corresponding to 11 different regions on chromosomes 1A, 4A, 4D, 5A, 6B, 7A and 7D were identified in independent SIM studies for leaf rust resistance. Six of these regions may represent putative new QTL, which have not been described earlier. For stripe rust, 21 QTL corresponding to 13 distinct chromosomal regions were detected, of which two may represent putatively new QTL located on wheat chromosomes 3D and 7D. Peak markers of the identified QTL were partly directly annotated with genes known to be involved in quantitative resistance to leaf and stripe rust. Additional promising gene annotations with different functions in relation to resistance responses were identified when considering ± 500 kb around each peak marker of a QTL.
The Bavarian MAGIC wheat population turned out to be well suited for the detection of QTL conferring resistance to leaf rust and stripe rust. Based on the phenotypic responses, RILs with increased resistance to both rust fungi were identified, which can be easily introduced into breeding programs due to their descent from elite parents
Influence of vineyard inter-row management on vegetative and bunch sanitary status, and grape yield and quality of two Sauvignon Blanc clones in Friuli Venezia Giulia (north-eastern Italy)
No full textThe vineyard inter-row management affects grapevine vegetative and bunch health status, as well as yield and grape quality parameters. Several studies assessed that cover-cropped inter-row in place of soil tillage often reduced plant vigour and yield but positively contributed to vineyard ecosystem services and, to a lower extent, to grape quality. In 2013 and 2014, two inter-row management strategies, i.e. soil tillage and mowing of spontaneous cover crops, were compared in an organic vineyard in north-eastern Italy and cultivated with \u27Sauvignon Blanc\u27 (Vitis vinifera L.), clones R3 and 297. In particular, the effects of tillage and mowing treatments on grapevine vegetative and bunch health status, yield and grape quality were evaluated. The vegetative parameters were lower in the mowing treatment than in the tillage one and in clone R3 compared to 297. The incidence of Botrytis cinerea was higher in the tillage treatment than in the mowing one and in clone 297 compared to R3. A significant reduction of the yield and bunch weight was ascertained in the mowing treatment, and these parameters were higher for clone 297 compared to clone R3. Titratable acidity was significantly higher in the tillage treatment than in the mowing one and in clone 297 compared to R3. Moreover, hue of berry skin was qualitatively better in the tillage treatment than in the mowing one. In the pedo-climatic conditions of Friuli Venezia Giulia (north-eastern Italy), the management of the vineyard inter-row with spontaneous cover crops proved to be effective to manage grapevine vigour, reducing yield and improving quality of the grapes during maturation
Effect of increasing zinc levels on Trigonella foenum-graecum growth and photosynthesis activity
Get PDFZinc is an indispensable element for the plant growth and the cellular metabolism. However, this mineral element becomes harmful athigh quantities. The effects of high zinc supply on different physiological parameters were investigated in fenugreek. Seedlings were grown in plastic pots filled with inert sand under five ZnSO4 treatments (C: control :1.5 μM Zn; 1mM, 2 mM, 3 mM and 4 mM ZnSO4). Results showed a decrease of 56% to 75% in shoot dry weight and a decrease of 65% to 90% in roots dry weight, relatively to the control. In addition we showed a significant reduction in photosynthetic parameters, with the highest value of CO2 assimilation under 1 mM Zn (3.3 μmol CO2, m-2·s-1) and a lower value under 4 mM Zn (0.5 μmol CO2, m-2·s-1). The concentration of zinc in plant shoot was around two folds the control under 1, 2 and 3 mM Zn and about four folds under the maximal concentration, 4 mM Zn. In roots, we showed a progressive increase of zinc content. Increasing zinc concentration induced a significant decrease of phosphorus concentration in shoot. Fenugreek was mainly affected by zinc excess greater than 1 mM ZnSO4, however at the highest concentration, fenugreek plants exhibited different adaptation strategies
Anthracnose susceptibility for grapevines with resistance loci to downy and powdery mildew in Southern Brazil
Get PDFAnthracnose, downy and powdery mildew are the principal fungal diseases of grapes in tropical and subtropical regions. The pesticide active ingredients that control downy and powdery mildew diseases provide some protection against anthracnose attack. The release of varieties with resistance alleles to downy and powdery mildew results in less pesticide use that can increase anthracnose attack. Thus, the present work aimed to evaluate anthracnose susceptibility of genotypes with resistance loci to downy and powdery mildew under Southern Brazilian conditions. Genotype susceptibility was tested, as well as the influence of the environment (location and crop season) on increased susceptibility to anthracnose infection. To accomplish the objective, a trifactorial design was established that included 20 genotypes, two locations, and two crop seasons. Anthracnose incidence and severity were evaluated under natural infection in the field. Temperature around 16 °C and relative humidity at 84 % increased susceptibility to anthracnose infection compared to temperature around 20 °C and relative humidity at 75 %. All tested genotypes with resistance alleles to downy and powdery mildew presented symptoms of anthracnose. \u27Baron\u27, \u27Cabernet Cortis\u27 and \u27Calardis Blanc\u27 showed the least susceptibility to anthracnose, whereas \u27Aromera\u27, \u27Felicia\u27, \u27Gf.2004-043-0004\u27 and \u27Gf.2004-043-0021\u27 were the most susceptible and bore symptoms of anthracnose. Other genotypes showed variable susceptibility during the evaluation period, depending on environmental conditions. Overall, all interactions among the three tested factors were highly significant