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In this study alternating magnetic field treatments at low frequency (60 Hz) with combinations of three magnetic flux densities (20, 60 and 100 mT) and three exposure times (7.5, 15 and 30 minutes) were used as pre-sowing seed treatm ents in three maize ( Zea mays L.) genotypes (CL-12 X CL-11, CL-4 X CL-1 and CL-13 x CL-1). In the cas e of CL-12 X CL-11 genotype these treatments increased significantly the seedling emergence rate, seedling dry weight and emergence in soil. The best treatment was found at magnetic flux density of 100 mT and exposure time of 7.5 min, with significant improvements in seedling emergence rate by 123.2%, field emergence by 110% and seedling dry weight, 21 days after plantin g, by 30.1%. In the case of CL-4 X CL-1 geno- type it was found a negative biostimulation for see dling emergence percentage; finally in the CL-13 x CL-1 genotype there was not any significant effect. These results show that electromagnetic field treatment provide a simple and ecologically well co mpatible method to improve seed vigour in maize but is necessary to find the optimal irradiat ion parameters to induce a positive biostimulation in the maize seeds which also depends on the seed g enotype.
Due to progress of ecological farming the breeders and farmers need to know how to store ecological cereal seed material. Investigations on the seed storage value of ecological and conventional seeds were performed on naked and hulled oat during 5 years of storage in a granary and long-term store. There were analysed germination capacity, mean germination time, vigour by the growth test according to ISTA method and response to drought stress. It was found that germination capacity and vigour were lowest for the organic seeds of cv. Polar stored in a granary. In the hulled cv. Krezus degradation process was delayed. In case of long-term storage, seed value was retained irrespective of the cultivar or method of cultivation. The highest response to drought stress occurred in organic seeds of cv. Polar taken from a granary. The response to drought stress of the hulled cv. Krezus was lower irrespective of method of cultivation.
Priming is a treatment applied for seed enhancement. Brassica vegetable seeds are commonly affected by Alternaria brassicicola. The changes in germination and vigour of kohlrabi (Brassica oleracea L. var. gongylodes L.) seeds subjected to two priming methods in the presence of A. brassicicola were investigated. The following treatments were applied: uninoculated non-primed seeds (control), seeds inoculated with A. brassicicola (2∙104 spores ml-1), uninoculated and inoculated seeds hydroprimed for 1–2 days, and uninoculated and inoculated seeds osmoprimed for 1–4 days. The percentage of germinating seeds, germination capacity, the percentages of diseased seedlings and dead seeds were determined. The speed of germination, tetrazolium staining index, and electrical conductivity described seed vigour. The presence of A. brassicicola on/in seeds was confirmed on CW semiselective agar. Osmopriming was conducive to penetration of A. brassicicola into kohlrabi seeds. The presence of the fungus had no influence on the percentage of germinating seeds, but a significantly lower germination capacity and a higher percentage of diseased seedlings and dead seeds were observed after inoculation. Non-primed inoculated seeds germinated faster than uninoculated ones. Despite the presence of A. brassicicola, osmotic priming improved seed vigour as measured by the speed of seed germination and electrical conductivity. The results of the tetrazolium vigour test showed its limited usefulness for seeds heavily infected with A. brassicicola.
The aim of the studies was to determine changes in the vigour of seeds of three spring triticale (x Triticosecale Wittm.) cultivars with various sprouting damages occurring during storage. It was found that the changes in vigour indices are mostly affected by sprouting damage and storage time, as well as by the interaction of these factors. The greatest significant reduction in the length of leaves and roots and the decrease in their dry weight, ranging from 25% to 90% as compared to the control, were observed in the most sprouted seeds. Seeds stored for eight months were characterized by the lowest electroconductivity values, which ranged from 117 to 157 μS·cm-1·g-1, and by the greatest respiration intensity. After 20 months of storing an increased, by 50%, outflow of electrolytes and decreased, in proportion to the seed damage degree, respiration intensity were observed. The correlation between seed respiration intensity and exudate electroconductivity, determined at that time, proved to be significant (r = -0.616*).
Experiments were conducted to study the influence of sowing seasons and drying methods on the seed vigour of two spring soybean (Glycine max (L.) Merr.) cultivars. Two cultivars, ‘Huachun18’ and ‘Huachun 14’, were sown in three seasons viz., spring, summer and autumn and the harvested seeds were dried using three different methods. The results showed that soybean sown in spring had a higher number of branches per plant, pods per branch and seed weight, and consequently resulted in higher seed yields than that of soybean sown in autumn or summer seasons. Seeds sown in the autumn season had the lowest values of electrical conductivity during seed imbibitions, higher peroxidase (POD) activity in germinated seedlings and lower contamination by the seed-borne fungi on the MS medium, which indirectly improved the seed vigour, which was followed by summer sown seeds. Seeds sown during the spring season resulted in poor seed vigour. In addition, the effect of drying methods on the seed vigour was also clarified. Seeds that hung for four days before threshing and then air-dried had the poorest seed vigour which was determined by germination, electrical conductivity, POD activity and seed borne fungal growth. There was no difference in seed vigour between other methods, i.e. seeds threshed directly at harvest and then air-dried on a bamboo sifter or concrete floor. These results indicated that autumn sowing soybean and the drying method in which seeds were threshed directly at harvest and then air-dried on a bamboo sifter resulted in higher seed vigour.
A vigour test that can predict the field emergence percentage of tree seeds accurately has long been a wish from growers. A new test method, the Critical Root Length (CRL) vigour test, was developed for beech seeds on the basis of the length of primary roots, germinated seeds can produce during a specified test. Pretreated, imbibed seeds were germinated in a vertically positioned moist paper roll during 20days at 15°C in 12 hour light daily. Root length of normally germinated seedlings was recorded and correlated with field emergence percentage to obtain a critical root length for the ability to emerge in the field. Critical root length for Fagus sylvatica was found to be 45 mm. The percentage of normally germinated seeds with roots longer than 45 mm in the CRL test is a predicted estimate of the field emergence percentage of a seed lot. Results of two tests on 5 and 10seed lots showed generally good correlation between CRL predicted emergence and actually obtained field seedling emergence. Large variation in root length was found between and within seed lots, thus displaying large differences in seed vigour. The new test is an applied, easy and inexpensive vigour test developed for nurserymen and seed technicians in order to predict field emergence more accurately.
The electrical conductivity values for winter triticale seeds with sprouting damage, harvested in three successive years after different time of storage were compared with vigour indices: germination ability, length of shoots and roots. The percentage of variance components for all sources of variation and the coefficients of correlation between vigour indices were estimated and discussed.
Wigor ziarniaków poddanych indukcji porastania w kłosach badano dla odmian pszenżyta ozimego: Bogo, Moreno, Vero w latach 1998–2000. Za pomocą testu c2 stwierdzono wpływ odmiany na występowanie zróżnicowanych uszkodzeń porostowych ziarniaków. Niezależnie od udziału poszczególnych grup ziarniaków z uszkodzeniami porostowymi, wigor i zdolność kiełkowania wykazały istotne współdziałanie odmian z latami. Odmiana Moreno o najwyższym procentowym udziale ziarniaków bez widocznych uszkodzeń porostowych charakteryzowała się największą zmiennością zdolności kiełkowania, która wahała się od 50,5–86,5% oraz wskaźników wigoru. Podobnie, dużą zmienność badanych parametrów stwierdzono dla ziarniaków kontrolnych tej odmiany.
The aim of this study was to investigate the effect of presowing conditioning, hormone permeation, and fungicide application on the vigour of seeds and seedlings as well as the yield of marjoram herb collected from the cultivation started by direct sowing into the open field. The methods of presowing seed treatment were as follows: soaking in GA3, matriconditioning with solid substance MicroCel-E, osmoconditioning in the solution of polyethylene glycol PEG 6000. Seeds of every combination were either dressed with Penncozeb or sown without fungicide. The yield and quality of marjoram herb were tested in the field experiments conducted in the region of Central and Southern Poland. The phytopathological analysis of seeds showed their low infestation by microorganisms, this not increasing following the seed conditioning and soaking in GA3 solution. The measurements of seedling vigour under controlled conditions proved the positive effect of every tested method of presowing seed treatment. Irrespective of localization, the yields of marjoram herb and essential oil were the highest with the crop from matriconditioned seeds. The effect of seed osmoconditioning and soaking in GA3 solution as well as fungicide application depended on the localization of marjoram growing.
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