INTERNATIONAL SYMPOSIUM RESEARCHES ON EVOLUTION OF CERTAIN CHARACTERISTICS RELATED TO MISCANTHUS SP. CROP SPRINGING, SIZE AND STRESS RESISTANCE / . URII DE MISCANTHUS SP. Eng. Dumitru C.*1), Ph.D. Eng. Marin E. 1), Eng. Iuga D.2) 1)INMA Bucharest / Romania; 2)SC METROUL SA / Romania Tel: 0758092438; E-mail: [email protected] Keywords: renewable energy, phenological observations, Miscanthus sp. ABSTRACT Directive 2009/28/EC regarding the Renewable Energy by 20 % for 2020 recommends to pass from a society based on fossil fuel to a renewable energy society. Bioenergy is a forefront component for achieving the objectives of Directive above by 2020. In the paper, some phenological observations are made, emphasizing the morphological and anatomic aspects based on Miscanthus sp. vegetative organs microscopic analysis. Role of presented researches is to participate in vegetal production increase by capitalizing the knowledge on the whole Miscanthus sp plant biological potential. REZUMAT . - . 2020. fenologice Miscanthus sp. lor prezentate în de Miscanthus sp. INTRODUCTION As a plant with photosynthetic cycle C4 with CO2 modified fixation, Miscanthus sp. has high productivity and a more efficient use of resources at which are added the reduced agronomy practice requirements; therefore, it is better adapted to biomass designed to produce energy (Plant Physiology 132, 2003). It has minimal nutritive demands- efficiently use nitrogen, so it is able to grow in dry land, without fertilization. Miscanthussp. is a sterile hybrid, so it can be multiplied by its rhizomes (Lewandowski et al.. 2000). Studies in course of development in Great Britain, United States and Ireland have boosted Miscanthussp.growth as a biomass source producing energy for direct burning or by cellulosic ethanol or biofuel producing. (National Non-FoodCrops Centre, 2008). Miscanthus sp. is being cultivated in Europe, especially for energy cogeneration (producing both electricity and heat within an integrated installation) and could supply up to12% out of the UE energy by 2050 (Dondini et al.. 2009). During 2008-2010, Technology for promoting in Romania the miscanthus energetic plant as renewable source for increasing energetic competitiveness and safety aimed to promote Miscanthus in Romania by partnership industrial research, within a specific regional, pedo- climatic and economic context for being afterwards extended to Romanian agricultural farms ( .. 2009). MATERIAL AND METHOD Material to be studied was Miscanthus sp. Plant, which has an interesting biomass potential for Romania, taking into account the large surfaces of available agricultural land (not entirely exploited). During vegetation stage,m some phenological observations were made, emphasizing the morphological and anatomic characteristics through vegetative organs microscopic analysis. 757 INTERNATIONAL SYMPOSIUM Within the paper, the Miscanthus sp.plant behaviour was studied in existing weather conditions in respective area (temperature, humidity, light intensity) and the physiological processes (photosynthesis, transpiration and absorption) and physical processes (humidity and ash content) were analyzed. The experimental areas, working variants and observation areas were randomly chosen being made on experimental plot planted with Miscanthus sp. at INMA Bucharest(figure1). Fig. 1 - Aspect of a Miscanthus sp. crop established at INMA Bucharest Miscanthus variety belongs to subphylum Magnoliophita, class Liliopsida, Poales order, Poaceae family, subfamily Panicoideae and comprises 15 species of perennial herbs coming from tropical and sub- tropical regions from Africa and Southern Asia, only one species (Miscanthussinensis) being found in temperate area of Eastern Asia. between Miscanthussinensis (diploid species. figure 2) and Miscanthussacchariflorus (tetraploid species) and is called Miscanthusgiganteus or "E-grass" (). Fig. 2 Miscanthussinensis (Hitchcock. A.S. (rev. A. Chase). 1950. Manual of the grasses of the United States. http://plants.usda.gov) Miscanthus sinensis grows in warm season and has extremely thin leaves. Above the leaves the rosy flowers are shaped in bobbles and in autumn they turn to a white-creamy colour.(figure 3). Fig. 3 - Miscanthus sinensis inflorescence (Steve Hurst. Providedby ARS SystematicBotanyandMycologyLaboratory. Japan. Sapporo. http://plants.usda.gov) 758 INTERNATIONAL SYMPOSIUM Miscanthus sacchariflorus(Amur silver grass, Silver banner grass) is a perennial grass with green and white flowers in early autumn or late summer. It grows very well in sun light having approximately 2.4 m height and about1. width and low tolerance to floods. Flowers of Miscanthus sacchariflorus are arranged in inflorescences named panicle (figure 4). Fig. 4 Miscanthuss acchariflorus (Maximowicz) Hackel. 1. Part of stem. rhizomes and panicle. 2. Spikelet pair. 3. Lower glume. 4. Upper glume. 5. Lowerlemma. 6. Upperlemma. 7. Upperpalea (FOC 582. FPRS 10(2):26. pl. 5. 1997. ShiWeiqing) At the end of summer, Miscanthus sacchariflorus produces panicles with soft silver white inflorescences (figure 5). Although in warm areas, the flowering can appear in the first year of growing, it is only in the second and next years that the plant will develop more vigorously. Fig. 5 -Miscanthus sacchariflorus inflorescence Jose Hernandez. Providedby ARS SystematicBotanyandMycologyLaboratory. China. Manchuria. http://plants.usda.gov The soil and climate conditions were determined with a digital system for microclimate monitoring (professional weather station of Delta-T Weather Stations-WS-STD1 type). For determining the physiological processes, there were used measuring cylinders, glass rod, light source, filter paper, analytical balance, water cristalliser and other consumables. In order to determine the physical processes there were used: hygrometer, ceramic crucibles, dessicator, analytical balance Shimadzu AW 220M, universal kiln MEMMERT UFE 500 and calcinations oven Nabertherm model P320. During the plant growth, phenological observations were made related to: - spring moment; - appearance of first leaves; - number of leaves per plant; - diameter and height of stem. In order to perform the microscopic analysis of vegetative organs, the material collected was brought in laboratory, where it was conserved. Transverse sections were made in the Miscanthus sp. plant aerial organs (stem, leaves). Descriptions were accompanied by photos performed at microscope ML 4M IOR. with PANASONIC LUMIX DMC LS60 camera (6MPX, optical zoom 3X). 759 INTERNATIONAL SYMPOSIUM One aspect during soil sampling in experimental field is shown in figure 6. Fig. 6 - Aspect during soil sampling in experimental field RESULTS Hygroscopic (inner colloidal) humidity is the water quantity that remains after the soaking moistening is removed. In order to determine the hygroscopic humidity of Miscanthus sp. , the oven heating at 105°C was used. Therefore, the following activities were performed: - ceramic crucible was weighted(m0); - by means of a spatula, the sample was introduced into the ceramic crucible, homogenized and the weighted (m1) twice by means of analytical balance, 5±0.0002 g out of Miscanthus sp.plant. - the crucible with sample was introduced into the universal oven heated at 105°C, where it remained for two hours, after which it was taken out and introduced into the dessicator till reaching the ambient temperature; - the sample was weighed again (m2) and hygroscopic humidity was calculated with formula (1): m m u 1 2 (1) Wh 100,[%] m1 m0 Result of determinations of Miscanthus sp. hygroscopic humidity is shown in table 1. Table 1 Sample Average hygroscopic humidity of Miscanthus sp. plant. % 1 54.46 Determination of ash content was made through the following stages: - the empty crucible was calcined up to constant mass, after which it was cooled and weighed (m1); - the analysis sample was homogenized (stirring for 1 minute); - 1...2 grams of fuel were taken and introduced into the crucible, levelled uniformly, by a light impact; - the fuel crucible was weighed (m2) with ±0.0002 g precision and it was introduced in calcination oven at ambient temperature; - the oven temperature was increased step by step to 600±25°C, so that it could be reached in minimum 60 minutes; - after reaching the temperature desired, the crucible remained in the oven for other 60 minutes; - the sample was taken out the stove, put on an asbestos plate for 5 minutes and after cooling, it was weighed (m3). The ash content out of the sample is expressed in percentages and was calculated by relation (2): m m Aa 3 1 100, % (2) m2 m1 Result of determinations of ash content is shown in table 2. Table 2 Sample Ash content of Miscanthus sp.. % 1 4.193 Morphological characteristics of species of Miscanthus sp.: - Rhizomes are plagiotrope (horizontal) on each bud that is forming every year ( figure 7). 760 INTERNATIONAL SYMPOSIUM Adventive roots rhizome Fig. 7 - Rhizomes of Miscanthus sp. - Leaves are alternatively placed, are sessile, made only of sheath and limb. The limb base in its crossing point with sheath presents its foliar parts- ligula and ears, that are hairy (figure 8) sheath ears Fig. 8 - Leaves of Miscanthus sp. Inflorescence is the panicle. The main axle is without hair ending with one little ear. The panicle branches are not hairy, being disposed on 6-9 levels (figure 9). inflorescence Fig. 9 - Inflorescence of Miscanthus sp. - Small ears have 2-3 flowers. Fruit is of caryopsis type (dry without unique seed)(figure10). flowers Fig. 10 - Flowers of