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Investigations on biological control of weeds in Romania  [cached]
Teodosie PERJU,Alexandru SALONTAI
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 1989,
Abstract: Conducted and systematic investigations on the biological control of weeds were not carried out both in this country and within the Agronomy Institute of Cluj-Napoca, namely by the Departament of Entomology (T. Perju 3-6). In 1985-1987, as a result of investigations led by the authors, there were traced down the troublesome weeds in the main agroecosystems as well as the carriers and phytophagous insects contributing spontaneously to the reduction of weed thickness in the crops and to reducing their spreading ability.
Jasenka ?osi
Poljoprivreda (Osijek) , 2002,
Abstract: Fusarium species are wide-spread and known to be pathogenic agents to cultivated plants in various agroclimatic areas. During a four year investigation 10 Fusarium species and Microdochium nivale were isolated from wheat, barley, maize and soybean as well as from 10 weeds collected from 10 locations in Slavonia and Baranya. Fusarium graminearum was dominant on wheat and barley, F. moniliforme on maize and F. oxysporum on soybean. Regarding weeds, the presence of the following Fusarium species was established: F. graminearum on Amaranthus hybridus, Capsella bursapastoris, Lamium purpureum, Sorghum halepense and Urtica dioica, F. moniliforme on Abutilon theophrasti, F. subglutinans on Polygonum aviculare, F. avenaceum on Capsella bursa-pastoris, Rumex crispus and Matricaria sp., F. culmorum on Abutilon theophrasti, F. sporotrichioides on Polygonum aviculare, F. proliferatum and F. poae on Artemisia vulgaris. Pathogenicity test to wheat seedlings was done in our laboratory on winter wheat cultivars Slavonija and Demetra (totally 146 isolates). The most pathogenic species to wheat seedilings were F. graminearum, F. culmorum and F. sporotrichioides and the least pathogenic F. moniliforme, F. solani, F. oxysporum and F. poae. Pathogenicity test for wheat ears was done on genotypes Osk.8c9/3-94 and Osk.6.11/2 (totally 25 isolates). The results obtained by our investigation showed that there were no significant differences in pathogenicity of Fusarium species isolated from both cultivated plants and weeds. Weeds represent a constant source of inoculum of F. species for cultivated plants and they serve as epidemiologic bridges among vegetations.
Scientific Annals of Alexandru Ioan Cuza University of Iasi. New Series, Section 2. Vegetal Biology , 2011,
Abstract: The article discusses about the variation of a few biochemical and physiological indicators which were performed on the foliar surface (the pigments chlorophyll content, the water content, the dry matter content, the intensity of photosynthesis and respiration process) and about the qualitative indicators of fruits (the total acidity and the concentration of sugar) at three apple varieties: Golden delicious, Idared and Starkrimson, cultivated in the orchard “M rul de aur”, Vaslui county. The investigations were determined in the phase of fruit ripening maturation, 2011. There were used leaves from two cardinal points taking into account the exposition of the trees: east and west. The results indicate functional and biochemical differences depending on each apple variety, geographical exposition of the tree and air humidity during the investigations.
Comparative Polyphenolic Content and Antioxidant Activities of Some Wild and Cultivated Blueberries from Romania  [cached]
Andrea BUNEA,Dumitri?a O. RUGIN?,Adela M. PINTEA,Zori?a SCON?A
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2011,
Abstract: Two wild and three cultivated blueberry varieties (‘Elliot’, ‘Bluecrop’ and ‘Duke’) from Romania were analyzed comparatively in order to determine the total polyphenols, total anthocyanins, total flavonoids content and measuring the antioxidant activity using three different single electron transfer-based assays, Trolox equivalent antioxidant capacity (ABTS), ferric reducing ability (FRAP), 2,2-diphenylpicrylhydrazil radical scavenging capacity (DPPH) and one hydrogen atom transfer-assay, oxygen radical absorbance capacity (ORAC). Total polyphenols content ranged from 424.84 - 819.12 mg GAE/100 g FW, total flavonoids ranged from 84.33-112.5 mg QE /100 g FW and total anthocyanins ranged from 100.58-300.02 C3GE/100g FW. The anthocyanins were separated and quantified using RP-HPLC-DAD. In Vaccinium myrtillus, petunidin-3-glucoside and delphinidin-3-glucoside have the highest contribution to the anthocyanin content while in Vaccinium corymbosum, peonidin-3-galactoside represent the major anthocyanin. Except for ORAC assay (r=0.765), all antioxidant activity values obtained were highly correlated with total polyphenol content (0.923≤ r ≤0.986). Wild blueberries had higher total polyphenols content and also antioxidant activity compared with cultivated ones.
Diversity and conservation of the Triticeae genetic resources

Lu Baorong,

生物多样性 , 1995,
Abstract: The tribe Triticeae Dumort. in the grass family (Poaceae) contains three of the world most important cereal crops, namely, wheat (Triticum aestivum L. ), barley (Hordeum vulgars L. ), and rye (Secale cerealeL. ), as well as many economically valuable forage grasses. Because the tribe Triticeae comprises a great number of species, covers a remarkably wide disribution area in the world, and inhabits various ecologicalenvironments, tremendous morphological and genetic variations are found between and within species in this tribe. As a vast reservoir of genetic resources, species in the Triticeae have a great potential for the improvement of wheat, barley, and rye varieties in the plant breeding programmes through transferring useful genes from wild to cultivated species. However, the present knowledge and investigation of biodiversity in the Triticeae is considerably insufficient, which largely affects the appropriate utilization of the genetic resources in the tribe. Nowadays, the change of the global environments makes some species of Triticeae in an endangered state. Therefore, it is very important and urgent to strengthen the further investigation of the genetic diversity in the Triticeae and to have effective strategy to the conservation of this vast genetic reservoir.
Scientific Annals of Alexandru Ioan Cuza University of Iasi. New Series, Section 2. Vegetal Biology , 2006,
Abstract: The Calamintha species, fam. Lamiaceae, originally from West and South Europe, were cultivated at SCDL Bac u. The essential oils were extracted by hydrodistillation; the separation and identifying of theirs components were made using a gas-chromatograph equipped with masspectrometrical detector. The obtained data emphasized a great variation of the composition of the essential oils. So, the essential oil from C. officinalis contained mainly pulegone and p-menthone; the one extracted from C.grandiflora contained germacrene D and β-cariophyllene; the essential oil from C. mentifolia contained rose furane; C. sylvatica provided an essential oil containing pulegone and isomenthone and the main components of the oil obtained from C. nepeta were estragol and menthone.
Quality of Chiretta (Swertia chirayita) in Cultivated and Wild Samples Collected from Different Districts of Nepal  [PDF]
Tanka P Barakoti,Narendra N Tiwari,Minoba Yonzon
Nepal Journal of Science and Technology , 2012, DOI: 10.3126/njst.v13i2.7715
Abstract: An experiment under the scaling up project of ARS Pakhribas was conducted to identify quality and compare the cultivated and wild Chiraito ( Swertia chirayita ) samples collected from eastern, central and western regions hill districts during 2004. This work aimed to identify best sites/ districts for quality production of this important medicinal herb through cultivation and conservation for initiating export of value added quality product in a sustainable way. Processed product is cheaper to send the overseas market as the volume and weight are decreased. Quality analysis is necessary to ensure quality standard of international market in the context of WTO. Assessment of the collected samples was done by quantifying the extract content and analyzing bitter principle in the Herbs Production and Processing Company lab, Kathmandu. The result revealed that extract content and bitter principle percent varied depending upon different agro-eco growing conditions and extraction method. Hot extraction gave more extract of the plant than cold percolation method. Wild samples, in general, contained higher bitter principle than cultivated, whereas extract content was higher in cultivated Chiraito. The international market could be better ensured with such study result. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 57-62 DOI: http://dx.doi.org/10.3126/njst.v13i2.7715
Karolina Vrande?i?
Poljoprivreda (Osijek) , 2004,
Abstract: A large number of weeds are alternative hosts to numerous pathogenic agents of fungus diseases to arable crops and they represent inoculum source to cultivated plants. The aim of our investigation was to determine weed mycopopulation, to establish pathogenicity of some fungi to cultivated plants as well as to choose potential parasites for biological control of weeds. During a two year investigation of weed mycopopulationobtained from root crops at five localities in East Slavonia and Baranya 32 fungus species were established at 25 weeds that were characterized by disease symptoms. Seven fungi species were determined on roots of 18 weeds, although there were no obvious disease symptoms. Obligated parasites along with 21 determined fungi are of Oomycetes, Plectomycetes and Hemibasidiomycetes genus. Facultative parasites from 18 determined fungus species are of Discomycetes, Pyrenomycetes, Coelomycetes and Hyphomycetes genus. Isolates of Sclerotinia sclerotiorum were tested for their pathogenicity to soybean. The results showed that there were no significant differences in pathogenicity of isolates in artificial conditions in laboratory. In natural conditions isolates from soybean were more pathogenic to soybean than the isolates from weeds. Experiments done with sunflower showed that the isolates from weeds were more pathogenic than isolates from sunflower. The isolates of Phomopsis/Diaporthe complex affected the length of germ, the length of necrosis and seed disease differently. Results showed that the isolates from weeds of Phomopsis species are pathogenic to soybean representing an important source of inoculum to soybean. Isolates of Fusarium species isolated from weeds were pathogenic for popcorn seedlings. Artificial infection of Abutilon theophrasti by Colletotrichum coccodes showed that foliar mass wilted earlier and whole plants died. For the first time in Croatia the presence of 14 fungus species was determined on 27 new hosts.
The Dynamics of Total Polyphenols, Flavonoids and Antioxidant Activity of Beepollen Collected from Moldavia Area, Romania
A. A. Prelipcean
Cercetari Agronomice in Moldova , 2012, DOI: 10.2478/v10298-012-0008-7
Abstract: The analysis sought to study the determination in timp and different conditions (temperature and light) of total polyphenols, flavones, total flavonoids and antioxidant activity from beepollen obtained with pollen colectors from Moldavia, Romania. Two methods vave been used, consisting in different concentrations of the methanolic solvent used. Analyses were performed on fresh pollen, stored for one and two weeks; at 4°C and 22°C; presence or absence of natural light. For every determination, five repetitions were made. There were fluctuations in the amounts of compounds, depending on the storage conditions and on the solvent used. The total polyphenols quantity ranged from 24.73 mg GAE/g to 28.8 mg GAE/g, when the methanolic solvent concentration was 96 % and from 21.67 mg GAE/g to 26.50 mg GAE/g, when the methanolic solvent concentration was 70 %. The flavones detected ranged from 7.23 mg QE/g to 8.93 mg QE/g (methanolic solvent 96%), and from 5.45 mg QE/g to 6.35 mg QE/g (methanolic solvent 70%). Total flavonoids have recorded values between 12.6 mg QE/g and 20.44 mg QE/g for the m.s. of 96%, and between 14.6 mg QE/g and 17.47 mg QE/g for the m.s. of 70%. The detected antiradical activity ranged from 22.68% to 29.78% inhibition (m.s. 96%), respectively from 21.31% to 25.55 % inhibition (m.s. 70%).
Allelopathic Activities of Some Weeds in the Asteraceae Family
O.J. Ilori,O.O. Otusanya,A.A. Adelusi,R.O. Sanni
International Journal of Botany , 2010,
Abstract: Helianthus annus, Chromolaena odorata and Tithonia diversifolia are weeds in the family Asteraceae. The present study was aimed to investigate the phytotoxic activities of these weeds on the seed germination and seedling growth of Vigna unguiculata. The seeds of the test crop were sown in petri dishes lined with filter paper moistened with the different aqueous extract prepared from the weeds while control received distilled water. The results showed that the germination and seedling growth of Vigna unguiculata were inhibited by the application of fresh leaf extract of Chromoleana odorata. All the different extracts inhibited the root length of the test plant. It was suggested that these weeds be controlled in the field where they grow in association with cultivated crops.
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