ROOT ZONE TEMPERATURE AFFECTS EMERGENCE AND GROWTH TRAITS OF SNAKE TOMATO (TRICHOSANTHES CUCUMERINA L.)

Two Nigerian morphological variants of Trichosanthes cucumerina L., (Cucurbitaceae) an under-exploited tropical leaf and fruit vegetable were evaluated for response to root zone temperature (RZT) in a climate controlled growth chamber at 20, 25 and 30 oC. The Green variant [V1] has long fruit with deep green background and white stripes at unripe stage while Light Green variant [V2] has light green coloured long fruit when at unripe stage. Results showed that the first emergence for seeds at RZT of 30 oC occurred at 7 days after planting (DAP) for both variants while those planted at RZT of 20 oC and 25 oC showed first emergence at 10 and 14 DAP, respectively. At RZT of 20 oC, 25 oC and 30 oC, days to 50% emergence were 18, 12 and 8 DAP while last emergence was registered at 24, 15 and 10 DAP, respectively. This work showed that under controlled growth chamber conditions, days to first emergence was reduced by 5 days compared to the 12 DAP recorded under tropical field conditions. Root zone temperatures (T) produced statistically significant (P ≤ 0.05) effects on the average number of tendrils, number of leaves, fresh leaf weight, stem length, fresh stem weight, root length, root weight and root volume while the main effect of T. cucumerina variants (V) and the interaction (V x T) produced no significant effects on all the parameters measured. The values recorded for each of the growth parameters were only numerically higher in the Green Variant (V1) compared to Light Green Variant (V2). The significantly highest value for each of the growth traits were recorded at 30 oC followed by 25 oC and 20 oC, in that order. Low root zone temperature of 20 oC produced adverse effects on both emergence and growth of T. cucumerina. This study established the need for providing soil warming facility for a successful cultivation of T. cucumerina in chilly (temperate) environment

UV-B induced damage and recovery processes in apple leaves as assessed by LIF and PAM fluorescence techniques

The capability of laser-induced chlorophyll fluorescence (LIF) and pulse-amplitude-modulated (PAM) fluorescence technique as well as RED/NIR-light reflection measurements for detection and quantification of UV-B induced damages was evaluated in greenhouse experiments with apple seedlings (Malus domestica Borkh.). Photosynthetic recovery from short-term UV-B stress was assessed during 7 days after UV-B treatment with the PAM fluorometer. The exposure of apple leaves to UV-B doses in the range of 10-26 W m-2 for 180 minutes (UV-BBE dose = 5.4-14 kJ m-2) affected neither chlorophyll content nor leaf reflection. Although UV-B damage was not visually evident 2 hours after irradiation, it could be detected by PAM and LIF fluorescence techniques with equivalent success. The intensity of LIF, estimated as the integral of fluorescence spectrum, was reduced after UV-B irradiation by 19-30%. A stronger decrease in F686 compared to F740 fluorescence resulted in significantly lower F686/F740 values in all UV-B treatments.Apple leaves displayed a strong and significant reduction in maximum fluorescence (Fm) and a slightly increase in ground fluorescence (Fo) 2 hours after UV-B treatment, as documented by PAM fluorescence measurement. Negative linear regressions between investigated UV-B doses and selected PAM parameters were found with determination coefficients (R2) of 0.50 for Fv, 0.48 for Fv/Fm, and 0.58 for Fv/Fo. Among the PAM and LIF parameters tested, the Fv/Fo ratio appeared most sensitive for detection of UV-B induced damages displaying greatest changes and strongest correlation with the applied UV-B doses. PAM fluorescence images of apple leaves visualised an enhanced spatial heterogeneity of photosynthetic activity with increasing UV-B dose. The disturbance in photosynthetic functionality was followed by a continuous recovery process as indicated by restoring Fo and Fm parameters. A decline in maximum photochemical efficiency Fv/Fm from 0.80 to 0.72 and 0.43 after exposure to 20 W m-2 for 240 and 360 minutes (UV-BBE = 14.4 and 21.6 kJ m-2), respectively, was followed by recovery at 7 x 10-4 and 5 x 10-3 units per hour during the first 48 hours after UV-B treatment. The recovery curves of Fm, Fv, Fv/Fm and Fv/Fo parameters during a week after UV-B irradiation were well fitted with exponential rise to maximum function, such as: y = yo + a (1 - e-bx). However, within 7 days after exposure to UV-B light, apple leaves displayed 14% or 4% lower Fm, and 5% or 1% lower Fv/Fm values compared with control plants, indicating only a partial recovery from photoinhibition and irreversible damages in PSII

Improvement of Mg uptake of grapevine by use of rapeseed oil ethoxylates for foliar application of Mg

To improve the uptake of foliar-applied Mg a new group of toxicological and ecotoxicological harmless surfactants (rapeseed oil ethoxylates) with an average of 5 (Agnique RSO 5®), 10 (Agnique RSO 10®), 30 (Agnique RSO 30®) and 60 (Agnique RSO 60®) units of ethylene oxide (EO) was evaluated as adjuvants for a MgSO4 and Mg(NO3) formulation. The impact of the surfactants on Mg penetration was studied using astomatous cuticular membranes isolated from mature tomato fruit. The biological efficacy of a formulation, containing castor oil, ionic and non-ionic surfactants with and without addition of RSO 5 was investigated in two vineyards at the Moselle valley, cvs Riesling and Regent. Especially RSO 5-surfactant increased Mg penetration through isolated cuticles. Under field conditions, Mg application enhanced significantly the Mg content in leaves. The Mg level in bunch stems merely increased when formulated 'Bittersalz' was applied. 'Magnisal' and formulated 'Magnisal' reduced markedly Mg deficiency symptoms in leaves and increased Mg content in leaves of cv. Regent.

Neue Methoden zur Bekämpfung des Echten Mehltaus im Ökologischen Landbau

Blattoberflächen-modifizierende Salzapplikationen sollten als Bekämpfungsmittel gegen Echten Mehltau an Tomaten und Gurken getestet werden hinsichtlich folgender Eigenschaften: - Wirkung verschiedener Salze - Blattverträglichkeit - Untersuchung der unterschiedlichen Wirkungsmechanismen mittels REM - Übertragbarkeit in praxisnahe Versuche. Die verschiedenen Salzlösungen und Kombinationen aus diesen Salzen unterschieden sich deutlich in ihrer Wirkung auf Gurkenmehltau. Die beste Wirkung ergab sich mit allenfalls geringer Schädigung des Blattes mit 0,1% MnCl2, 1 % Patentkali (K2SO4/MgSO4) und 1% Knöterichextrakt. MnCl2 liegt auf Grund seines niedrigen Deliqueszenzpunktes ständig gelöst auf der Blattoberfläche vor, wogegen sich Knöterichextrakt und Patentkali auf der Blattoberfläche in einer Art „Salzkriechen“ verteilen durch häufigen Wechsel zwischen Trocknen und Wiederverflüssigung. Salzschäden ließen sich verringern durch Zusatz von Netzmitteln zur Sprühlösung. Rasterelektronische Visualisierung zeigte für alle untersuchten Lösungen einen direkt toxischen Effekt auf die Mehltausporen und ihre Hyphen in jeder Entwicklungsphase des Pilzes. Eine Verbesserung des Nährstoffstatus der Pflanzen scheidet als Wirkungsmechanismus aus, da alle Pflanzen optimal ernährt waren und die Behandlungen zu keinen signifikanten Veränderungen der Nährstoffgehalte in den Blättern führten. Besonders chloridische Salze führten z.T. zu erheblicher Nekrotisierung der Blätter. Da diese Salzlösungen jedoch auch in geringer Konzentration in der Lage waren, die Ausbreitung des Echten Mehltau effektiv zu verhindern, sollten Möglichkeiten zur Mikrodosierung dieser Salze geprüft werden. Extreme Witterungsbedingungen im Sommer 2003 führten dazu, dass Praxistests nicht ausgeführt oder normal beendet werden konnten. Es gilt jedoch als sicher, dass einige der untersuchten Salzmischungen in geringen Konzentrationen (zw. 0,1 und 1%) den Befall mit Echten Mehltaupilzen effektiv reduzieren können, ohne Blattoberflächen zu schädigen

Partitioning multi-dimensional sets in a small number of ``uniform'' parts

In this paper we prove that every finite subset of ZxZ can be partitioned into a small number of subsets so that, in each part all vertical sections have aproximately the same size and all horyzontal sections have aproximately the same size. The generalization of this statement is used to give a combinatorial interpretation to every information inequality

Inequivalent representations of commutator or anticommutator rings of field operators and their applications

Hamiltonian of a system in quantum field theory can give rise to infinitely many partition functions which correspond to infinitely many inequivalent representations of the canonical commutator or anticommutator rings of field operators. This implies that the system can theoretically exist in infinitely many Gibbs states. The system resides in the Gibbs state which corresponds to its minimal Helmholtz free energy at a given range of the thermodynamic variables. Individual inequivalent representations are associated with different thermodynamic phases of the system. The BCS Hamiltonian of superconductivity is chosen to be an explicit example for the demonstration of the important role of inequivalent representations in practical applications. Its analysis from the inequivalent representations' point of view has led to a recognition of a novel type of the superconducting phase transition.Comment: 25 pages, 6 figure

The influence of continuous casting and extrusion processes on the properties and structure of CuNi2Si alloy and the morphology of the Ni-Si phase precipitates

CuNiSi alloys are widely used in various mechanical and electrical applications. These group of materials, due to the phenomena of precipitation hardening, are able to obtain high mechanical properties with also relatively high electrical properties. In the article authors compare two different types of products, made from the CW111C alloy i.e. rods which were continuously cast on the horizontal laboratory casting set-up (low degree of structure refinement) and rods commercially extruded with high degree of structure refinement. The presented results of experimental work characterize the tested materials in terms of their chemical composition, mechanical and electrical properties depending on the manufacturing process, as well as reveal their structures and the effect of heat treatment on the morphology of the Ni-Si precipitates

The influence of continuous casting and extrusion processes on the properties and structure of CuNi2Si alloy and the morphology of the Ni-Si phase precipitates

CuNiSi alloys are widely used in various mechanical and electrical applications. These group of materials, due to the phenomena of precipitation hardening, are able to obtain high mechanical properties with also relatively high electrical properties. In the article authors compare two different types of products, made from the CW111C alloy i.e. rods which were continuously cast on the horizontal laboratory casting set-up (low degree of structure refinement) and rods commercially extruded with high degree of structure refinement. The presented results of experimental work characterize the tested materials in terms of their chemical composition, mechanical and electrical properties depending on the manufacturing process, as well as reveal their structures and the effect of heat treatment on the morphology of the Ni-Si precipitates

Omalizumab may decrease IgE synthesis by targeting membrane IgE+ human B cells

Omalizumab, is a humanized anti-IgE monoclonal antibody used to treat allergic asthma. Decreased serum IgE levels, lower eosinophil and B cell counts have been noted as a result of treatment. In vitro studies and animal models support the hypothesis that omalizumab inhibits IgE synthesis by B cells and causes elimination of IgE-expressing cells either by induction of apoptosis or induction of anergy or tolerance. METHODS: We examined the influence of omalizumab on human tonsillar B cell survival and on the genes involved in IgE synthesis. Tonsillar B cells were stimulated with IL-4 plus anti-CD40 antibody to induce class switch recombination to IgE production in the presence or absence of omalizumab. Cell viability was assessed and RNA extracted to examine specific genes involved in IgE synthesis. CONCLUSIONS: We found that omalizumab reduced viable cell numbers but this was not through induction of apoptosis. IL-4R and germline Cϵ mRNA levels were decreased as well as the number of membrane IgE+ cells in B cells treated with omalizumab. These data suggest that omalizumab may decrease IgE synthesis by human B cells by specifically targeting membrane IgE-bearing B cells and inducing a state of anergy