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The purpose of the study, carried out in the years 2001–2003 was to determine which fungal species inhabited decaying grapevine cuttings during callusing and soon after planting them into pots. The plant material was collected from 5 commercial plantations and 8 cultivars, which were most frequently cultivated. From each plantation and cultivar 20 cuttings with symptoms of the growth inhibition or decay were randomly sampled during the callusing period i.e. March/April (term I) and 2–3 months after planting the cuttings into pots i.e. June/July (term II). The results showed that from affected grapevine cuttings Phomopsis viticola, Botrytis cinerea, Alternaria alternata and Fusarium spp. were isolated most frequently. Moreover, it was found that after planting young cuttings into the pots, numerous isolates of soil borne pathogenes were obtained, among others Cylindrocarpon spp., Phytophthora sp., Rhizoctonia solani, Fusarium spp.
Challenges concerning fruit trees and grapevines as long lived woody perennial crops require adapted biotechnological approaches, if solutions are to be found within a reasonable time frame. These challenges are represented by the need for correct identification of genetic resources, with the foreseen use either in conservation or in breeding programmes. Molecular markers provide most accurate information and will be the major solution for questions about plant breeders rights. Providing healthy planting material and rapid detection of newly introduced pathogens by reliable methods involving serological and molecular biological tools will be a future challenge of increases importance, given the fact that plant material travels freely in the entire European Union. But also new breeding goals and transgenic solutions are part of the biotechnological benefits, e.g. resistance against biotic and abiotic stress factors, modified growth habits, modified nutritional properties and altered processing and storage qualities. The successful characterization of transgenic grapevines and stone fruit trees carrying genes of viral origin in different vectors constructed under ecological consideration, will be presented. Beyond technical feasibility, efficiency of resistance, environmental safety and Intellectual Property Rights, also public acceptance needs consideration and has been addressed in a specific project. The molecular determination of internal quality parameters of food can also be addressed by the use of biotechnological tools. Patient independent detection tools for apple allergens have been developed and should allow to compare fruits from different production systems, sites, and genotypes for their content of health threatening compounds.
Th e main aims of this study were to determine the overwintering form and the primary inoculum of Erysiphe necator, the causal agent of grapevine powdery mildew in southern Syria. Eleven vineyards located at fi ve diff erent geographical sites were visited every week from March to November in 2014 and 2015. Th e results of fi eld and histopathological studies showed that E. necator survived as mycelium in dormant grapevine buds during the winter season. Th e fi rst fl ag shoots were observed shortly aft er bud break in spring. Th e number of fl ag shoots varied greatly according to vineyards, cultivars and years, being present on 27.4 to 61.9% of the grapevines in 2014, and on 5.2 to 40% of the grapevines in 2015. Th e percentage of fl ag shoots on the same grapevine also varied according to the year, cultivar and location. It was between 4.3 to 9.4% in 2014, and 2.1 to 3.6% in 2015. Th e disease was observed only on Balady and Black cultivars. Conidia were released from the second week of May to early September. Th e fi rst conidia were trapped around mid-May, and the fi rst secondary symptoms were observed on leaves from mid-May to early June according to the site. Chasmothecia were observed on leaves in 45.5% of the studied vineyards. Th e fi rst observation of chasmothecia on leaves was in July, and their numbers varied greatly between vineyards and years. Chasmothecia were not detected on bark, nor were ascospores trapped at the beginning of the season. Th ese results confi rmed that the ascospores did not have any role in the initiation of spring infection. To the best of our knowledge, this is the fi rst report of the overwintering form of E. necator in Syria.
The paper aims to identify factors under climate change conditions that could impact innovativeness in grapevine growing in Poland. It is shown that today the viticulture cultivation in Poland is of little economic significance. However, based on primary data applied to econometric model, it is argued that driven by climate changes as well as due to other factors, grapevine growing might become a significant branch of agriculture. The estimates of the model, although randomized, suggest that there is a significant probability that in Polish viticultural farms adaptation measures applied as a respond to these factors will result with implementation of innovations and through overall development.
Few studies examined the stomatal conductance (gs) characteristics of grapevines with an emphasis on daily climatic responses. In the present study, diurnal measurements on leaf temperature and gs of three grapevine cultivars (Alphonse Lavallée, Crimson Seedless and Italia) were carried out. The leaf temperature values for the cultivars at 08:30 were 25.0 ±1°C and it increased to a maximum value between 12:00 and 14:50 p.m. After an almost steady course, it decreased along with the decrease in ambient temperature. The gs values increased from morning (08:30 a.m.) to mid-morning (10:30 a.m.) for all the cultivars. After reaching a peak level at mid-morning, the gs decreased gradually from the mid-morning throughout the afternoon. In the morning, the highest and the least gs values were obtained from Italia (232 mmol H2O m-2 s-1) and Crimson Seedless (149.6 mmol H2O m-2 s-1) cultivars. At around 10:30, the gs for Italia, Crimson Seedless and Alphonse Lavallée were at the highest levels with their valus 287.7, 262.1 and 242.0 mmol H2O m-2 s-1, respectively. The last measurements on gs at around 16:10 varied from to 96.7 (Italia) to 112.0 mmol H2O m-2 s-1 (Alphonse Lavallée). During the daily time course, the gs depended mainly on irradiance. Tleaf showed a strong relationship with Tair for all the cultivars. There was a strong, but negative correlation between leaf temperature and air humidity for all the cultivars.
The study shows genetic diversity of 38 Vitis vinifera L. cultivars and hybrids originating in North America and Europe, including cultivars selected in Poland, which have not been characterized with the use of DNA markers yet. The agrobiological features of the genotypes selected for testing indicate that they may be useful for the breeding of new cultivars and grape production. The use of 12 ISSR primers allowed to obtain 94.4% of polymorphism. The polymorphic information content (PIC) value was high and varied between 0.829 and 0.953 with an average of 0.897. The resolving power (Rp) ranged between 3.678 and 8.892 with an average of 6.347. Primers UBC 809, UBC 810, UBC 812, UBC 855, UBC 891 and UBC 810 were found to be highly effective (informative). Similarity coefficient ranged between 0.167 and 1.0, which indicates high degree of diversity of tested grape cultivars. Tested cultivars were grouped in 3 main clusters; one of them was further divided into 6 subclusters. ‘Pannonia Kincse’ and ‘Danmarpa Polonia’ were not differentiated. Phenotypic differences among those two cultivars suggest that ‘Danmarpa Polonia’ might be a clone of ‘Pannonia Kincse’ and other molecular techniques must be used to differentiate them. Morphological and agrobiological characters of cultivars support the results obtained by ISSR markers.
Climate and weather conditions are important factors influencing grapevine growth and fruit quality. Cooler regions are expected to be unsuitable for grape growing due to insufficient maturation and variability of quality parameters. Therefore, a field trial was conducted, aimed to determine the effect of pruning time on low cordon cane (CP) and spur pruned (SP) grapevines of the hybrid cultivar Hasanski Sladki in a cool climate conditions. A vineyard, with the low double trunk (25 cm in height) training system, was established at the experimental station of the Estonian University of Life Sciences (58°23’17’’ N, 26°41’50’’ E) in June 2007. The treatments were carried out in autumn after leaf fall and in spring at the two leaf phase in 2010/2011 and 2011/2012. Pruning time affected grape maturity parameters depending on pruning method. Autumn SP increased the soluble solids content from 18.5 to 19.8 °Brix in 2011 and from 17.1 to 18.0 in 2012. Titratable acids content was high in both experimental years ranging from 1.3 to 2.1 g 100 g-1, and only autumn CP decreased it. Pruning in spring significantly decreased the soluble solids/ titratable acids for both pruning methods. The timing of SP affected the maturity index (MI = °Brix × pH2 ) variably; in 2011, spring pruning decreased the index whereas; the index was increased in 2012. Spring pruning decreased the total phenolics up to 22% in both treatments in the two years mean. In CP, spring pruning increased anthocyanins content from 31 to 77 mg 100 g-1 in 2012.
Testing the globally popular grapevine rootstocks for affinity with new grape cultivars or tolerance potential to stress factors like drought is essential for districts where supplemental irrigation is more frequently needed due to the pressures of a global climate change. In this study, a seasonal evaluation of leaf gas exchange, leaf temperature, leaf greenness (chlorophyll content prediction) and vegetative development of Vitis vinifera L. cv. ‘Prima’ grafted to different rootstock genotypes having great variability in drought tolerance, were investigated. The experiment was conducted in a controlled experimental glasshouse on two-year-old soilless grown ‘Prima’ vines grafted on nine rootstocks [44-53 M, 5 BB, 140 Ru, Ramsey (Syn. Salt Creek), 99 R, Saint George (Syn. Rupestris du Lot), 41 B, 1613 C and 420 A]. A long-term deficit irrigation (DI) was imposed before bud break by reducing water supply to 40% of field capacity derived from concurrent measurements of water content of growth medium and maintained until the end of vegetation period. The rootstocks significantly modulated the physiology and vegetative growth of the scion cultivar in varying degrees according to their genetic features. Among them, 140 Ru rootstock found to be more prominent in terms of mitigating the adverse effect of water deficit on physiology and growth of the scion genotype ‘Prima’ as there were no significant difference between deficit and full irrigation treatments for most of parameters investigated. In general, the ‘Prima’ scion performed better when the rootstocks coming from V. berlandieri × V. rupestris pedigree rather than the others including V. berlendieri × V. riparia.
The effect of nine fungicides and chitosan on the viability of Phomopsis viticola Sacc. spores occurring abundantly in pycnidia on carnation leaves, was tested in the laboratory conditions. The chemicals selected represent different mode of action on the pathogen and they were recognized as very effective in limiting P. viticola development within many viticultural regions. Fungicides were tested at six various concentrations of active ingredients, i.e. 10, 50, 100, 200, 500 mg. a.i./cm3 and at the concentrations that were recommended by the manufacturers. It was found that chlorothalonil, flusilazol and thiophanate – methyl caused the decay of all P. viticola spores in each studied concentration. After using mancozeb, cyprodinil, azoxystrobin and chitosan a strong inhibition of spore viability were also observed, especially at the concentrations of 100 mg of a.i. on cm3 and above. The other fungicides seem to be less effective compared with the above-metioned ones. Basing on the present studies and abundant information from literature, some of the most effective chemicals which should be tested on grapevine plantations in Poland were indicated.
In this study, effects of topical applications of two plant growth promoting rhizobacteria (PGPR) strains and their combination (Bacillus BAI6, OSU142 and BAI6+0SUI42) on the rooting of 41B and Rupestris du Lot rootstocks were investigated. The results showed that none of the bacterial strains have significant effects on success rate at 41B and Rupestris du Lot alone, but BA16+0SU142 combination significantly increased the rooting rate and rooting degree of 41 B, and decreased the rooting rate and rooting degree of Rupestris du Lot compared with control. In addition, none of the applications had significant effects in number, length and weight of roots on cuttings of both 41B and Rupestris du Lot. Our results suggest that PGPR may have a great potential to stimulate the rooting of hardwood cuttings of grapevine rootstocks, with low rooting capability.
The tested material consisted of grapevine Vitis californica stratified seeds germinated under optimum conditions (+25°C in water), under osmotic stress (-0.2 MPa in PEG solution) and submitted to recovery after stress (+25°C in water). The germinating seeds were determined to contain tannins, catechins and the following phenolic acids: gallic, caffeic, p-coumaric and ferulic. The acids occurred in free, ester- and glycoside-bound forms. The dominant form of phenolic acids was the ester-bound fraction. Gallic acid was the most abundant phenolic acid in germinating seeds, while ferulic acid appeared in the smallest amounts. Our analysis of tannins demonstrated that osmotic stress depressed their concentration. Presence of catechin group compounds such as catechin and epicatechin was also determined. In each sample epicatechin was dominant. The total concentration of catechin increased under stress conditions and declined during post-stress recovery. Catechins are a constituent of tannins and their increase under osmotic stress is most probably caused by the breakdown of some tannins in seeds germinating under stress conditions. Samples submitted to osmotic stress were also found to contain less of total phenolic compounds, whereas in samples which underwent post-stress recovery the total level of phenolic compounds increased. Compared to extracts from seeds germinating under optimum conditions, osmotic stress depressed the capacity of extract to scavenge DPPH● (2,2-diphenyl-1-picrylhydrazyl) and ABTS●+ – 2,2-Azino-bis (3-etylbenzothiazoline-6- -sulfonic acid) free radicals, but the antioxidant activity rose in seeds submitted to recovery after stress. Positive correlation was therefore demonstrated between the total content of phenolic acids in germinating grapevine seeds and the reducing power of extracts obtained from these seeds and their free radical scavenging activity. The results suggest that osmotic stress inhibits the activity of antioxidizing enzymes in germinating grapevine seeds. Thus, the antioxidative defence system is largely blocked under osmotic stress. It seems that a very high oxidoreductive potential in grapevine tissues prior to occurrence of osmotic stress is essential for maintaining proper homeostasis of oxidation and reduction reactions.
During a survey on fungi associated with decline symptoms on grapevine cultivars growing in Kurdistan region of Iraq, several isolates of Botryosphaeria species were encountered. All isolates were identified as Botryosphaeria parva Pennycook and Samuels. Pathogenicity test for isolate DKI 1 was performed on two cultivars, Taefi and Rashmew. Under greenhouse conditions, one-year grape rooted cuttings were inoculated with the pathogen isolate by two methods, injecting the spore suspension into the green shoots and by artificial inoculation of wounded shoots with mycelial mat. The highest canker length (15.0 mm) was produced after four months on the shoots of the Taife cultivar artificially inoculated with mycelial mat of the pathogen. Under field conditions, two methods of inoculation were adopted, wounding the green shoots and drilling a hole in the arms of mature vine, followed by inoculation with mycelial mat. The highest canker length (11.17 mm) was obtained after 5 months on wounded shoots of the Rashmew cultivar and with a significant difference from the Taefi cultivar. The pathogen caused a reduction in fresh and dry weight of green shoots and roots compared with the non-inoculated control. This is the first report on B. parva in Iraq.
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