Aladjadjiyan A.,Agricultural University of Plovdiv
International Agrophysics | Year: 2010
The paper describes the investigation of magnetic field treatment on the development of lentil seeds. Stationary magnetic field has been used. The germination energy and germination, length of stems and roots, measured on the 7th and 14th day, as well as the total mass have been used in order to evaluate the effect of magnetic field treatment. The germination energy and germination of seeds have not shown significant differences between variants. The length of stems and roots, measured on the 7th and 14th day, as well as the total mass have shown dependence from the dose of treatment, better expressed for the parameters measured on the 14th day. © 2010 Institute of Agrophysics, Polish Academy of Sciences.
Zlatev Z.,Agricultural University of Plovdiv |
Lidon F.C.,New University of Lisbon
Emirates Journal of Food and Agriculture | Year: 2012
At a whole plant level the effects of drought is usually perceived as a decrease in growth and photosynthetic carbon assimilation. That is why this review is focused mainly on recent information about the effects of drought on plant growth, water relations and photosynthesis, as well as mechanisms of adaptation. It is shown that plants have evolved a great number of adaptive mechanisms that allow the biochemical systems to cope with increased water deficit. The literature analyzed in this review shows the complexity of tolerance to water deficit and supports the statements of many authors that the flexibility of cell metabolism and its fast acclimation to changes in environmental conditions is a first essential step in stress avoidance.
Petrov S.,Agricultural University of Plovdiv
Biologia (Poland) | Year: 2013
Identification key of 20 species of the genus Trissolcus registered in Bulgaria is given. Three species, T. fuscus sp. n., T. simplex sp. n. and T. nigricans sp. n. are described as new for science. © 2013 Versita Warsaw and Springer-Verlag Wien.
Nakova M.,Agricultural University of Plovdiv
European Journal of Plant Pathology | Year: 2010
Disease on fruit trees in Bulgaria caused by Phytopthora cactorum and P. citrophthora was found in the period 1998-1999. Leaves of some trees become reddish during July, and later in the season fall off. Infected trees die during the same season, or the next season. Observations on symptom development and spread of Phytophthora root and crown rot of fruit trees was undertaken from 1999 to 2009. Disease incidence is between 2% and 14% in some gardens and nurseries. The disease was registered in the regions of Plovdiv, Kjustendil, Sliven, Yambol, Karnobat, Bourgas and Svishtov. Samples from infected plant tissues were taken and isolations were done on selective PARP media, or by applying a baiting bioassay. Based on morphological and cultural characteristics and temperature requirements the following Phytophthora species have been identified: Phytophthora cactorum, P. citrophthora, P. drechsleri, P. cryptogea, hybrid and Pythium. Pathogenicity of the isolates was tested on green apple fruits or one-year-old apple rootstocks. Laboratory studies of the effect of temperature on mycelia growth showed that most isolates can grow from 5° up to 30°C, with an optimum from 18° to 25°C. Only three strains grew at 35-36°C, two developed slowly, one grew well. The optimal pH for mycelia development was tested. Aiming at control of disease, in vivo pot trials have been carried out for studying resistance of rootstocks to P. cactorum. At the end of the growing season a good level of resistance has been shown in the rootstocks M29C, Gizela 6, and MAXMA 14. © 2010 KNPV.
Kostova D.,Agricultural University of Plovdiv
Journal of Analytical Chemistry | Year: 2011
Solvent extraction of molybdenum(VI) ion associate with triphenyltetrazolium chloride (TTC) has been studied. TTC was proposed as reagent for the spectrophotometric determination of micro amounts of molybdenum(VI) at λmax 250 nm. The optimum conditions for extraction of molybdenum(VI) as an ionassociation complex with TTC has been determined. Beer's law is obeyed in the range of 0.5-10 μg/mL molybdenum(VI). The molar absorptivity of the ion-pair is 1 × 106 L/mol cm. The sensitivity of the method is 9.6 × 10-5 μg/cm 2. The characteristic values for the extraction equilibrium and the equilibrium in the aqueous phase are: distribution constant K D = 32.64, extraction constant K ex = 2.19 × 1010 association constant β = 6.71 × 108. The interferences of different cations, anions on molybdenum(VI) determination were also investigated. A sensitive and selective method for the determination of microquantities of molybdenum(VI) has been developed. The determination was carried out without preliminary separation of molybdenum. A novel procedure of molybdenum(VI) extraction and spectrophotometric determination in different plant samples was examined. © Pleiades Publishing, Ltd., 2011.