What do biological powerhouses look like? How do they work? Why does generating a single “dose of energy” demand a highly complicated process? Why do seeds age? Answers to all these questions are to be found in one of the most complex cellular organelles: the mitochondrion.

What strategies do plants use in trying to disperse their seeds, so as to colonize distant areas? Is it more advantageous to have tiny seeds as light as a feather, or tough and heavy acorns?

On the basis of the presented studies, it was established that seed dressing by coating protects effectively onion crops against onion fly (Hylemyia antiqua Meig.). In all seed dressing treatments, a significant decrease of number of dam- aged plants was found in comparison to the control. The highest efficacy in protection of onion against onion fly was shown in the case of insecticide Super Homai 70 DS. The effectiveness of this seed dressing reached 80.40% in the year 2001 and 85.44% in the year 2002.

In view of the ecological hazards of chemicals, pot experiments were conducted to determine the efficacy of Trichoderma sp. against Macrophomina phaseolina. Greenhouse evolution of the interaction between M. phaseolina isolates and Trichoderma sp. isolates revealed a very highly significant (p = 0.0000). M. phaseolina isolate x antagonist isolate interaction for all the following parameters: preemergence damping-off, postemergence damping-off, survival, plant height, and dry weight. This interaction implies that a single isolate of antagonist can be highly effective againstan isolate of M. phaseolina, but may have only minimal effectsonotherisolatesof M. phaseolina. Therefore, isolates of antagonist should be tested against as many isolates of M. phaseolina as possible, as this will improve the chance of identifying antagonist isolates effective against several isolates of M. phaseolina.

In this study, two species belonging to the genus Allium and distributed in Turkey are investigated. A thick cuticle is observed on the epidermis of the scapes of the species. The epicuticular layer is not evident in Allium scorodoprasum ssp. rotundum (L.) Stearn. Secretory cavities have been formed in the pith region of the species. Vascular bundles are in the form of two rings, one above and one below the sclerenchymatic ring. The cross- section of the leaf of Allium brevicaule Boiss. & Balansa is circular, unlike A. scorodoprasum ssp. rotundum. In both species, the stomata are located lower than the epidermis cells. The seeds of A. brevicaule are smaller than in A. scorodoprasum ssp. rotundum and they are polygonal shaped. The testa cells of A. brevicaule seeds have scalariform and tuberculate ornamentation. A. scorodoprasum seeds have reticulate sculpture testa. The species have sulcate pollen types. The pollen form of A. brevicaule is perprolate, and that of A. scorodoprasum ssp. rotundum is subprolate. The apertures in both species are monosulcus. In A. brevicaule, the sulcus does not extend to the poles at the proximal end. Therefore, the differences in the scape and leaf anatomy, as well as in palynology and micromorphology, can be used to distinguish Allium species.

The aim of the presented investigations was to examine changes in the intensity of dehydrogenase and acid phosphatase activities as well as of the dynamics of selected groups of microorganisms in the soil under the cultivation of winter triticale following the application of the following seed dressings: (a.s.) flutriafol 2.5% + fludioxonil 2.5% in two doses and (a.s.) carboxin and tiuram. The experiment had a field character. The number of microorganisms (total bacteria, fungi, oligotrophic, copiotrophic and Azotobacter) was determined by the plate method on adequate agar substrates. Activity levels of the selected enzymes were defined using the spectrometrical method.

The obtained results indicate a change in the dehydrogenase and phoshatase activity in soil depending on the seed dressing applied in the experiment as well as at the date of investigations. The number of microorganisms in the soil underwent fluctuations depending on the developmental stage of triticale and the applied fungicide. The performed experiment demonstrated that counts of microorganisms in the soil underwent fluctuations depending on the developmental stage of triticale and the applied fungicide.

Currently, Prosopis laevigata (mesquite) has been affected by the Bruchinae coleoptera pest, whic feeds on its seed and causes significant losses in production and grain storage. In the Hñähñu community El Alberto (Ixmiquilpan, Hidalgo, Mexico), the use of aqueous extracts from garlic and nettle as botanical insecticides against different pests in agricultural fields is a known practice. Herein, we assess the efficacy of the method known by locals in the protection of mesquite seeds. Two tests were conducted: 1) Insecticidal effect on adult bruchins, and 2) Seed preservation test from Bruchinae infestation, with a germination test in seeds exposed to the treatments. There are probable insecticidal effects on immature stages of Bruchinae since there were no mortality effects on their adults during the first test. Mortality on adults in the second test was 75.6% with garlic and 50% with nettle. Nettle extract had more efficacy in seed protection with an infestation rate of 4%, whereas 27.5% of the seeds exposed to garlic extract were infested. Seed germination rate was 2.38% with nettle extract, and 1.19% with garlic extract. The method known by local inhabitants requires modifications to increase its efficacy and possible use in Integrated Pest Management in the future.

Salinity is one of the most significant abiotic stress factors influencing crop production, especially in arid and semi-arid regions. Plants’ response to salinity stress depends on the cultivated genotype. A pot experiment was conducted to study the impact of two concentrations of sodium chloride (4 and 6 dS∙m–1) on some physiological and production traits of 58 chickpea genotypes. A genetic variation in the response of the investigated chickpea genotypes for NaCl-induced salinity stress was noted. Studied morphophysiological traits and yield components were affected under salt stress in all genotypes tested. Plant height was observed to have the lowest rate of reduction (32%, 48%) at 4 and 6 dS∙m ^–1, respectively. Leaf stomatal conductance decreased as salinity increased. Salinity stress conditions affected all studied yield components, but there was a genetic variation in the response of the studied genotypes. Under no stress conditions and compared to the other genotypes, the number of pods was significantly higher in BG362 genotype. The seed number was significantly higher in ILC9076 genotype. The 100 seed weight was significantly higher in the genotype ILC2664. The mean seed yield was significantly higher in ILC9354 and the harvest index was significantly higher in ILC8617. In general, salinity stress caused the reduction of all parameters. We assume that the assessment of tolerance of chickpea ( Cicer arietinum L.) genotypes to salinity stress should be based on a complex of morpho-physiological traits and analysis of yield complement.

Fructification of Stratiotes aloides L. is very rarely recorded at present. In general, there are only one sex representatives in each lake basin, which simply makes generative reproduction difficult. The subfossil seeds of Stratiotes aloides have been found in five localities of biogenic accumulation in northern and central Poland.

One of the most serious seed-borne diseases of flax is anthracnose or seedling blight caused by Colletotrichum lini (West.) Toch. This disease affects flax seedlings, leaves, stems, and fruit bags. It causes reductions in linseed germination power, stand density, stem and linseed yield, fibre output and quality. During 1999-2001 experiments were carried out at the Lithuanian Institute ofAgriculture Upyte Experimental Station to test the efficacy of seven fungicides used for seed dressing against flax anthracnose and other seedborne diseases. Experimental findings indicated that 19.0% to 34.0% of flax seeds were annually infected with C. lini (West.) Toch. causing flax anthracnose. As the disease can spread through the soil, on control plots sown with untreated with fungicides seeds 33.0% to 79.5% of seedlings showed symptoms of anthracnose. Seed treatment with Sportak 45 EC used at the dose 0.8 l f1 and Maxim Star 025 FS used at the dose 1.51 t-1 gave the best control of seedling blight causal agents. Their biological efficacy was as follows: against seed anthracnose 97.3% and 96.3%, at seedling stage, 76.5% and 76.3%, at 'fir-tree' stage - 67.8% and 60.4%. Biological efficacy of the other seed treaters was lower. The highest straw yield increases resulted from seed treatment with the Maxim Star 025 FS and Sportak 45 EC - 0.5 and 0.3 t ha" or 11.0% and 6.2%, respectively. The effect of fungicides used for seed treatment on linseed yield was similar. Maxim Star 025 FS increased the yield on average by 22.1%, and Sportak 45 EC and Premis 25 FS by 13. 7% and 13.3%. The other fungicides, except for Raxil 2 WS and Rovral FLO, also had a positive effect on flax straw and linseed yield, however, in all experimental years the increases were not higher than the least significant difference.

Investigations on the occurrence of Barley stripe mosaic virus (BSMV, Hordeivirus) in Poland were performed by testing seeds of 22 barley cultivars. BSMV was detected in seeds of winter barley cv. Tiffany and of spring barley cvs. Scarlett and Stratu s. The virus presence was revealed by ELISA test and then confirm ed by electron microscopy. Preliminary data on the rate of seed transmission of BSMV in cvs. Scarlett and Stratus are presented.

The experiment was conducted in the years 2001–2003 at the Experimental Station in Złotniki. The aim of the performed investigations was to evaluate economic effectiveness of different fungicidal protection programs in winter wheat. Winter wheat of cv. Sakwa was cultivated using the following two variants of seed treatment: 1) Raxil 060 FS at the dose of 60 ml/100 kg grain, 2) Raxil 060 FS + Latitude 125 FS at the doses of 60 and 200 ml/100 kg, and five variants of fungicidal foliar protection: 1) Vista 228 SE, 2) Sportak Alpha 380 EC, 3) Sportak Alpha 380 EC + Vista 228 SE, 4) Sportak Alpha 380 EC + Vista 228 SE + Juwel 250 SC, 5) control – without protection. The use of the above plant protection products contributed to the increase of winter wheat grain yield from 0.60 t/ha to 2.07 t/ha. This increase of yield covered costs of performed chemical control. The economic analysis showed that most effective variant of winter wheat chemical protection was seed treatment with Latitude 125 FS with additional two foliar treatments with the following fungicides: Sportak Alpha 380 EC and Vista 228 SE. Irrespective of the applied seed dressing, additional application of Juwel 250 SC at the stage of early milk maturity turned out to be economically not justified.

Cabbage seed weevil (Ceutorhynchus assimilis Payk.) is one of the most important and dangerous pests of oilseed rape in Poland and in other European countries. In contrast to another important oilseed rape insect pest – pollen beetle (Meligethes aeneus F.), little is known about cabbage seed weevil susceptibility level to insecticide active ingredients. Therefore, the aim of this study was to determine the cabbage seed weevil susceptibility to active ingredients from different insecticide groups. Research, carried out in 2015, 2016 and 2017 revealed very high susceptibility of the pest to organophosphates and all pyrethroid active ingredients, except for tau-fluvalinate, lower susceptibility to thiacloprid and very high resistance to indoxacarb from oxadiazines. This information is a basic element for creating integrated pest management strategies for oilseed rape in Poland.

Six isolates of Trichoderma spp. (belonging to species; Trichoderma harzianum and T. longibrachiatum) were applied as seed or soil treatments to suppress damping-off of seedlings of ten cotton cultivars under greenhouse conditions. In most cases, cultivar x isolate interaction was a highly significant (p < 0.01) source of variation in the tested seedling growth parameters: incidence of disease, seedling height, and seedling dry weight. This interaction implies that a single isolate of Trichoderma can be highly effective in controlling the disease on a cotton cultivar but may have minimal efficiency in controlling the disease on another cultivar. It was also found that, in most cases, cultivar x isolate x application method was a highly significant source of variation (p < 0.01) in the tested growth parameters. Cotton cultivars showed differences in the disease reaction to the biocontrol agents. In the experiments evaluating the Trichoderma antagonists and their effect on seedling disease, a highly significant (p < 0.01) experimental treatment interaction was found. This interaction suggests that the outcome of cultivar x isolate interaction is markedly affected by the application method. Thus, the application method should be chosen to maximize the outcome of this interaction. The degree of the control of seedling disease in cotton differed according to the isolates of antagonists, the application method and cultivars.

Seed-borne diseases of wheat such as Fusarium head blight (FHB), a fungal disease caused by several species of Fusarium, results in reduced yield and seed quality. The aim of this study was to identify the Fusarium species, the effect of Fusarium-infected seeds on germination and vigor indices and to determine the location of Fusarium spp. in seeds, as well as to investigate the pathogenicity and variability of aggressiveness of the isolates obtained from pre-basic seeds wheat fields in Iran. According to morphological and molecular characters, the species F. graminearum, F. culmorum, F. avenaceum and F. poae were identified. Among the isolates, F. graminearum was the predominant species with the highest frequency and relative density of 92.9% and 70.9%, respectively. We observed that germination and vigor indices were decreased due to increased Fusarium-infected seeds. Results indicated significant differences among cultivars and seed-borne Fusarium levels. While a higher infection level of Fusarium spp. most commonly occurred in the seed coat, only F. graminearum was observed in embryos. Our study about pathogenicity showed that 77.3% of the Fusarium spp. isolates were not pathogenic and 22.7% isolates of Fusarium spp. were pathogenic or weakly pathogenic. Our results indicated that variability in aggressiveness among isolates of a species and positive correlation may be determined by pathogenicity tests. This is the first time the location of Fusarium spp. in seeds has been identified. It is also the first time that Fusarium-infected seeds in pre-basic seeds wheat fields of Iran have been evaluated.

In this study, rubber seed/shea butter oil was used to formulate core oil. The formulated core oil was characterised. D-optimal mixture design was used for multi response optimisation of the functional properties of rubber seed-shea butter coil oil. Desirable values for some responses might be obtained from a factor combination while for others responses not so desirable values. Through multiple response optimisations, a factor setting that gives the desirable values for all responses was obtained. The selected optimum mixture setting for the formulated core oil is 65.937% Rubber seed and 34.063% Shea butter oil at desirability of 0.924. Under the optimum condition the functional properties of the core oil was found to be 39.57KN/M2, 626.85KN/M2, 36.63KN/M2, 593.906KN/M2, 412.605 and 167.309s for Green Compressive Strength, Dry Compressive Strength, Green Tensile Strength, Dry Tensile Strength, Permeability and Collapsibility respectively. The optimum conditions were validated with less than 0.2% error. The functional properties of the formulated core oil was compared to the functional properties of linseed core oil. It was found that rubber seed-shea butter core oil can be used for producing cores suitable for Aluminium casting.

Light exposure is an important environmental factor which breaks seed dormancy in many plant species. Phytochromes have been identified as playing a crucial role in perception of the light signal that releases seed germination in Arabidopsis. Phototropins (Phot1, Phot2) are blue/UV-photoreceptors in plants which mediate phototropic responses, chloroplast relocation, hypocotyl growth inhibition and stomata opening. We studied germination under different light conditions in Arabidopsis Phot1-null and Phot2-null mutants and in a double phot1phot2 mutant. Germination of single phot1 and phot2 mutants in darkness was much lower than in wildtype (WT) seeds, whereas double phot1phot2 mutant lacking both functional phototropins germinated at frequency comparable to WT seeds, irrespective of light and temperature conditions. Light treatment of imbibed seeds was essential for effective germination of phot1, irrespective of low-temperature conditioning. In contrast, cold stratification promoted dark germination of phot2 seeds after imbibition in dim light. Low germination frequency of phot1 seeds under low light intensity suggests that the presence of functional Phot1 might be crucial for effective germination at these conditions. The lower germination frequency of phot2 seeds under continuous light suggests that Phot2 might be responsible for stimulating germination of seeds exposed to direct daylight. Thus, the phototropin system may cooperate with phytochromes regulating the germination competence of seeds under different environmental conditions

Poor seed set is a limiting factor in alfalfa breeding, as it slows the selection response. One strategy used to overcome this problem is to search for mutations of inflorescence morphology. Long-peduncle (lp), branched-raceme (br) and top-flowering (tf) inflorescence mutations increase the number of flowers per inflorescence, but they do not improve seed set per flower. Here we assessed pollen tube growth in styles of those inflorescence mutants and we observed embryo and endosperm development in seeds 1 to 16 days after pollination (DAP). The number of pollen tubes penetrating the style and the ovary was similar in all tested mutants and in the reference cultivar Radius. At 2 DAP, fertilized ovules were 2.7-3.9 times less numerous in certain inflorescence mutants than in the short-raceme cv. Radius. Ovule degeneration progressed at 2-4 DAP in all analyzed plants. Most ovules were not properly developed in the control cultivar (62%), nor in the forms with mutated inflorescence morphology (69-86%). The number of seeds per pod was lowest in the tf form despite its having the highest number of ovules per ovary. It appears that the number of ovules per pistil is not a crucial factor in seed set in alfalfa when fertilization efficiency is very low. Both poor fertilization and gradual ovule degeneration were factors causing poor seed set in the investigated alfalfa genotypes.

Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the reproduction biology of Colobanthus quitensis (Caryophyllaceae) growing in natural conditions in the Antarctic and in a greenhouse in Olsztyn (northern Poland) showed that this plant develops two types of bisexual flowers: opening, chasmogamous flowers and closed, cleistogamous ones. Cleistogamy was caused by a low temperature, high air humidity and strong wind. A small number of microspores differentiated in the microsporangia of C. quitensis , which is typical of cleistogamous species. Microsporocytes, and later micro − spores, formed very thick callose walls. More than twenty spheroidal, polypantoporate pollen grains differentiated in the microsporangium. They germinated on the surface of receptive cells on the dry stigma of the gynoecium or inside the microsporangium. A monosporic embryo sac of the Polygonum type differentiated in the crassinucellar ovule. During this differentiation the nucellus tissue formed and stored reserve materials. In the development of generative cells, a male germ unit (MGU) with differentiated sperm cells was observed. The smaller cell contained mainly mitochondria, and the bigger one plastids. In the process of fertilization in C. quitensis only one nucleus of the sperm cell, without cytoplasm fragments, entered the egg cell, and the proembryo developed according to the Caryophyllad type. Almost all C. quitensis ovules developed and formed perispermic seeds with a completely differentiated embryo both under natural conditions in the Antarctic and in a greenhouse in Olsztyn.

The current research aimed to use non traditional methods to control some stored grain insects. The effects of 180 millitesla (mT) magnetic field (MF) for six different exposure periods (3 min, 30 min, 1 h, 12 h, 24 h and 48 h) on mortality (%) of two stored grain insects, Tribolium casteneum adults and Trogoderma granarium larvae, reduction in F1-progeny (%), seeds germination (%) and seed components (%) after 8 months storage period were studied under laboratory conditions. According to results, the mortality (%) of tested insects increased with increasing of MF time exposure. Trogoderma granarium was more resistant than T. casteneum in which mortality reached 56 and 75%, respectively 14 days after from exposure period. Without any negative effect on seeds germination (%) the MF was very effective in protecting stored wheat from insect infestation up to 8 months compared to non-magnetic seeds which became infested after 3 months of storage. Furthermore, the germination (%) was accelerated by 6 h compared to non-magnetic seeds. The MF level caused a slight increase in the percent of total carbohydrate, crude protein and ash while slightly decrease the percent of moisture, total fats and crude fiber.

Appropriate agrotechnical measures make it possible to optimise plant cultivation and obtain yields of the highest quality with an appropriate economic production index. The aim of the study was to evaluate different sowing density and row spacing on the morphological and mechanical properties of white lupine ( Lupinus albus L.) seeds. The field experiment was conducted at the Experimental Station for Variety Evaluation in Przecław (50°11'25.2" N, 21°28'55.0" E). The experiment was established at two row spacings (15 cm and 30 cm) and three sowing densities (60, 75, 90 plants per m ²). Mechanical parameters evaluated included destructive force F_D (N), relative deformation D_R (%) and destructive energy E_D (mJ). Seed morphological properties such as weight, length and width were also assessed. Sphericity was also calculated. In the present study, improvements in the mechanical properties of the seeds were obtained by increasing the plant density per unit area of the experiment. In the case of morphological characteristics, only the weight of the analysed lupine seeds changed significantly as a result of row spacing. On the other hand, sowing density did not significantly affect morphological traits. of white lupine seeds. Apart from the spacing and sowing density of plants, the weather conditions in particular years of research were an important factor determining the properties of seeds. Determining the optimum sowing density and row spacing in the field contributes to the optimisation of the production process. Quasi-static mechanical tests are often used to obtain reasonable data on the physical properties of plant materials.

Rhizoctonia solani was isolated from 91 % of alder and birch seedlings with stem rot symptoms and 2-3% of seeds. Sowing of seeds to substratum infested with R. solani resulted in pre-and postemergence damping off. On leaves and stem parts of alder and birch, inoculated with 3 isolates of R. solani, necrosis spread from 0.22 to 0.52 mm/hr.

In the Institute of Plant Protection Branch in Sośnicowice an investigation was performed on establishing novel methods for testing biological activity of seed dressings against snow mould (Microdochiwn nivale). Seeds of winter wheat used for the experiments in artificial conditions were disinfected in sodium hypochlorite, subsequently infected with the pathogen, and treated with seed dressing fungicides (Baytan Universal 19.5 WS, Zaprawa Funaben T, Maxim 025 FS, Raxil Extra 515 FS and Vitavax 200 FS). In laboratory tests inoculation with conidial suspension was applied, and in climatic chamber experiments either conidial suspension or inoculum grown on sand-cornmeal medium was used. The field experiment with the same seed dressings was carried out on naturally infested plots, and the disease developed under snow cover lasting for 58 days. Two novel climatic chamber methods (Z and PK) proved to be suitable for testing biological activity of seed dressing fungicides against snow mould (M nivale) as correlation coefficients with field results at P=0.05 were 0.9760 and 0.9453. Method Z was recognised as more suitable. Differences between seed dressings were statistically insignificant. The laboratory method was recognised as useful for controlling the pathogen (M. niva!e), but its usefulness for controlling the disease (snow mould) may not be sufficient under a range of different winter conditions.