Failure of androgenesis in Miscanthus × giganteus in vitro culture of cytologically unbalanced microspores

Miscanthus × giganteus is a popular energy crop, which due to its hybrid origin is only vegetatively reproduced. Asexual embryogenesis in anther and microspore culture leading to double haploids production could allow to regain the ability for sexual reproduction and to increase the biodiversity of the species. Therefore, the goal of this paper was to investigate the requirements of androgenesis in Miscanthus. The standard protocols used for monocotyledonous plants were applied with many modifications regarding the developmental stage of the explants at the time of culture initiation, stress treatment applied to panicles and isolated anthers as well as various chemical and physical parameters of in vitro culture conditions. Our results indicated that the induction of androgenesis in M. × giganteus is possible. However, the very low efficiency of the process and the lack of regeneration ability of the androgenic structures presently prevent the use of this technique

Reducing flower competition for assimilates by half results in higher yield of Fagopyrum esculentum

Despite abundant flowering throughout the season, common buckwheat develops a very low number of kernels probably due to competition for assimilates. We hypothesized that plants with a shorter flowering period may give a higher seed yield. To verify the hypothesis, we studied nutrient stress in vitro and in planta and analyzed different embryological and yield parameters, including hormone profile in the flowers. In vitro cultivated flowers on media with strongly reduced nutrient content demonstrated a drastic increase in degenerated embryo sacs. In in planta experiments, where 50% or 75% of flowers or all lateral ramifications were removed, the reduction of the flower competition by half turned out to be the most promising treatment for improving yield. This treatment increased the frequency of properly developed embryo sacs, the average number of mature seeds per plant, and their mass. Strong seed compensation under 50% inflorescence removal could result from increased production of salicylic and jasmonic acid that both favor more effective pollinator attraction. Plants in single-shoot cultivation finished their vegetation earlier, and they demonstrated greater single seed mass per plant than in control. This result suggests that plants of common buckwheat with shorter blooming period could deliver higher seed yield

Sterility of Miscanthus × giganteus results from hybrid incompatibility

Miscanthus ×giganteus Greef et Deu. (Poaceae), a hybrid of Miscanthus sinensis and M. sacchariflorus native to Japan, is an ornamental and a highly lignocellulosic bioenergy crop, cultivated in the European Union as an alternative source of energy. This grass reproduces exclusively vegetatively, by rhizomes or via expensive in vitro micropropagation. The present study was aimed at finding the barriers that prevent sexual seed production, based on detailed embryological analyses of the whole generative cycle, including microsporogenesis, pollen viability, megasporogenesis, female gametophyte development, and embryo and endosperm formation. Sterility of M. ×giganteus results from abnormal development of both male and female gametophytes. Disturbed microsporogenesis (laggard chromosomes, univalents, micronuclei) was further highlighted by low pollen staining. The frequency of stainable pollen ranged from 13.9% to 55.3% depending on the pollen staining test, and no pollen germination was observed either in vitro or in planta. The wide range of pollen sizes (25.5-47.6 μm) clearly indicated unbalanced pollen grain cytology, which evidently affected pollen germination. Only 9.7% of the ovules developed normally. No zygotes nor embryos were found in any analyzed ovules. Sexual reproduction of M. ×giganteus is severely hampered by its allotriploid (2n=3x=57) nature. Hybrid sterility, a strong postzygotic barrier, prevents sexual reproduction and, therefore, seed formation in this taxon

Effects of zearalenone and 24-<i>epi</i>brassinolide on the salt tolerance of select monocotyledonous crop plants

Salinity has an increasing impact on crop production worldwide. Contemporary agricultural practices increasingly use plant biostimulants that protect plants against various environmental stresses. The aim of the work was to investigate whether such stimulants as 24-epibrassinolide (EPI) and zearalenone (ZEN) may alleviate effects of salinity in bread and durum wheat, maize, and sorghum plants. Plants were grown in glasshouse, in pots filled with perlite under continuous salinity stress (120 mM of NaCl). Four-week-old plants were treated with the stimulants. The plant responses to salinity were determined analyzing the following parameters: fresh and dry weights of plants, water content, electrolyte leakage, proline, abscisic acid, and the soluble carbohydrate contents in the leaves. The positive effect of ZEN on the studied parameters was more frequently observed than in the case of EPI. ZEN increased the root mass of both wheat species, as well as the stem and root masses of sorghum. This stimulant improved water relations in bread and durum wheat. Both stimulators increased the content of soluble carbohydrates. ZEN elevated significantly abscisic acid content in sorghum plants as well as it increased strongly proline level in all studied plant species. ZEN was more effective in alleviation salinity disorders than EPI.

Metody analizy i oceny bezpieczeństwa oraz jakości informacji

Praca recenzowana / Peer-reviewed paperTematyka monografii koncentruje się na metodach zapewnienia bezpieczeństwa informacji, procedurach wspomagających podnoszenie jakości danych oraz narzędziach zwiększających możliwości pozyskiwania z dostępnych informacji wartościowych i rzetelnych wniosków analitycznych. Publikacja podzielona jest na trzy części. Pierwsza część zawiera 3 rozdziały, w których podjęto kwestie zapewnienia bezpieczeństwa informacji. Druga część monografii, ujęta w kolejnych trzech rozdziałach, prezentuje wybrane narzędzia i modele organizacji zasobów cyfrowych mających na celu zapewnienie wysokiej jakości, użyteczności oraz wiarygodności zbiorów danych zawartych w repozytoriach. Ostatnia część pracy przedstawia problematykę związaną z prawem Benforda, pozwalającym ocenić stopień rzetelności danych na podstawie analizy rozkładów cyfr w liczbach weryfikowanego zbioru danych

Metody i narzędzia zapisu i udostępniania danych

Praca recenzowana / Peer-reviewed paperPrzekazujemy czytelnikowi kolejną monografię wydaną w ramach serii „Informatyka”, zawierającą publikacje pracowników związanych z Wydziałem Zarządzania i Komunikacji Społecznej Krakowskiej Akademii im. Andrzeja Frycza Modrzewskiego z obszaru problemów optymalizacji, systemów informacyjnych oraz kształcenia zdalnego. Wśród autorów niniejszej publikacji znajdują się głównie pracownicy Studium Informatyki Krakowskiej Akademii i Katedry Informatyki Stosowanej. Opublikowane artykuły są wynikiem współpracy w zespołach z pracownikami innych krakowskich uczelni. Tematyka monografii koncentruje się na metodach optymalizacji, zastosowaniach systemów informatycznych, oraz kształcenia zdalnego. Całość tematyki podzielona jest na trzy wzajemnie powiązane części. Pierwsza część zawiera trzy podrozdziały, w których podjęto kwestie kształcenia zdalnego. Druga część monografii, ujęta w kolejnych trzech podrozdziałach, prezentuje wybrane narzędzia i modele optymalizacji. Ostatnia, trzecia – przedstawia problematykę związaną z zastosowaniem systemów informatycznych w firmie

An Attempt to Restore the Fertility of Miscanthus &times; giganteus

Miscanthus &times; giganteus is a popular industrial plant with great potential in ecological agriculture. It forms numerous rhizomes that are important in the sequestration of carbon dioxide. The plant can be a source of lignin and cellulose, biomass for renewable energy production, and can be used in small garden architecture, or to strengthen the banks of landslides. Breeding this species is difficult, as it is a sterile allotriploid with 57 chromosomes. The aim of the study was to obtain fertile plants of this species by treating its callus and regenerants with chromosome doubling agents such as colchicine, oryzalin, trifluralin, and caffeine at variable concentrations and durations. Callus cells naturally showed large variations in the number of chromosomes but only euploid cells regenerated plants. Treatment of the regenerants with 1252 &micro;M colchicine for 18 h allowed for obtaining two hexaploid shoots; however, they died before flowering. Colchicine and oryzalin stimulated the formation of mixoploid shoots. The investigated substances, except for caffeine, were highly toxic to plants. M. &times; giganteus plants with 114 chromosomes may die because such a high number of chromosomes may be unfavorable for cells of this species

An Attempt to Restore the Fertility of <i>Miscanthus</i> × <i>giganteus</i>

Miscanthus × giganteus is a popular industrial plant with great potential in ecological agriculture. It forms numerous rhizomes that are important in the sequestration of carbon dioxide. The plant can be a source of lignin and cellulose, biomass for renewable energy production, and can be used in small garden architecture, or to strengthen the banks of landslides. Breeding this species is difficult, as it is a sterile allotriploid with 57 chromosomes. The aim of the study was to obtain fertile plants of this species by treating its callus and regenerants with chromosome doubling agents such as colchicine, oryzalin, trifluralin, and caffeine at variable concentrations and durations. Callus cells naturally showed large variations in the number of chromosomes but only euploid cells regenerated plants. Treatment of the regenerants with 1252 µM colchicine for 18 h allowed for obtaining two hexaploid shoots; however, they died before flowering. Colchicine and oryzalin stimulated the formation of mixoploid shoots. The investigated substances, except for caffeine, were highly toxic to plants. M. × giganteus plants with 114 chromosomes may die because such a high number of chromosomes may be unfavorable for cells of this species

The Effect of Stimulants on Nectar Composition, Flowering, and Seed Yield of Common Buckwheat (<i>Fagopyrum esculentum</i> Moench)

Common buckwheat is a valuable plant producing seeds containing a number of health-promoting compounds and elements. Buckwheat does not contain gluten and is characterized by an excellent composition of amino acids. This species is also a melliferous plant. Despite many advantages, the area of buckwheat cultivation is decreasing due to unstable yields. One of the reasons for low seed yield is its sensitivity to drought, high temperatures, and assimilate deficiencies. These factors have a significant impact on the nectar composition, which is important for visiting pollinators and thus for pollination. High temperature during flowering increases the degeneration of embryo sacs and embryos, which is high anyway (genetic determination) in common buckwheat. This phenomenon seems to be unbreakable by breeding methods. The authors aimed to determine whether stimulants commonly used in agriculture could increase the seed yield of this plant species. The aim of the work was to choose from eight different stimulants the most effective one that would improve the seed yield of two accessions of common buckwheat by increasing the efficiency of nectar production and reducing the number of empty seeds. The plants were sprayed at either the beginning of flowering or at full bloom. The content of sugars and amino acids was higher in the nectar produced at the beginning of flowering. The nectar of both lines included also polyamines. The level of sugars in the nectar increased mainly after spraying with the stimulants in the second phase of flowering. A positive correlation between the total amount of sugars and amino acids in the nectar and seed yield was found. All the stimulants used reduced the number of empty seeds in both accessions. Seed production in the PA15 line increased significantly under the influence of all stimulants used at the beginning of flowering, and the most effective were ASAHI SL and TYTANIT®