Evaluation of lawn... 75,, 75-84 EVALUATION OF LAWN GRASS CULTIVARS REPRESENTING THE GENUS FESTUCA AT THE INITIAL STAGE OF GROWTH BASED ON THE MORPHOMETRIC ROOT SYSTEM STUDIES* Zofia Stypczyńska 1, Andrzej Dziamski 1, Jan Schmidt 2 1 University of Technology and Life Sciences in Bydgoszcz 2 Institute of Plant Breeding and Acclimatization in Bydgoszcz 1 Abstract. The study was carried out in 2010 in the area of the IHAR Botanical Garden in Bydgoszcz. In two experiments eight lawn cultivars were assessed, belonging to three grass species of the genus Festuca: F. arundinacea (Schreb.), F. rubra (L.), F. ovina (L.). The first experiment involved the evaluation of single plants, which grew in pots placed in a cold frame up to the stage of 6-10 completely formed leaves. In the second experiment for a period of two months grasses grew in cuvettes placed in a cold frame. In each experiment the weight of roots, their length and aboveground weight of grasses were determined. Indexes of root productivity and root density in soil were calculated. Lawn assessment was carried out, taking into consideration general aspect and a sod cover degree of the lawn. The highest parameters of assessed traits were found in one of cultivars (Tarmena) F. arundinacea. The lowest values were found in cultivars of F. ovina, which at the same time were characterized by the highest rate of increase in root weight and length. Cultivars of F. rubra, due to the chewing or creeping structure of the underground weight, showed differentiation in respect of analyzed traits and calculated indexes. Key words: individual plants of grasses, root length, root weight, sod condition INTRODUCTION Species of the genus Festuca are used on a large scale in lawn mixtures. These species are resistant to drought and in natural conditions are among the first grasses to colonize areas deprived of vegetation. Of them, three species are worth special consideration: tall fescue Festuca arundinacea (Schreb.), sheep s fescue Festuca ovina Corresponding author Adres do korespondencji: dr inż. Zofia Stypczyńska, Department of Botany and Ecology of University of Technology and Life Sciences in Bydgoszcz, Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, e-mail: styzo@utp.edu.pl * Scientific work financed from budget for science in 2009-2011 as a research project
76 Z. Stypczyńska, A. Dziamski, J. Schmidt (L.) and red fescue Festuca rubra (L.). These species are used among other things for sodding areas with unfavorable moisture conditions and the top layer of soil inclined to dry off which is destroyed and easy to dry. In the former studies of lawn grasses the main attention was focused on their aboveground weight, analyzing such features as: the general aesthetic aspect of the lawn, its sod cover, and the color and leaf structure [Prończuk et al. 1997, Domański 1998, Żurek 2006, Jankowski et al. 2012]. To obtain lawn sod of a good quality, it is necessary to form rozległych, deep roots, well penetrating the soil, which play an important role in plant metabolism from the beginning of their growth and ensure survival under unfavorable climate and soil conditions [Harkot and Czarnecki 1998, 1999, Dziamski et al. 2007]. Finding the structure of root systems in the initial period of growth and quantitative and qualitative evaluation of the aboveground part of grasses will contribute to broadening the knowledge about relationships which occur between those parts of plants. Such studies may be also used for breeding work over obtaining new cultivars of lawn grasses. The aim of this study was to evaluate grass cultivars of the genus Festuca in the initial period of growth based on the morphometric analyses of roots. MATERIAL AND METHODS The study was conducted from April to June 2010 in the area of the IHAR Botanical Garden in Bydgoszcz. In the experiment eight lawn cultivars were evaluated belonging to three grass species of the genus fescue (Festuca): tall fescue (Festuca arundinacea) Fa, cultivars Rahela and Tarmena, red fescue (Festuca rubra) Fr, creeping cultivars Adio and Dark and chewing cultivars Nimba and Rapsodia, sheep s fescue (Festuca ovina) Fo, cultivars Mimi and Noni. The evaluation of morphological structure of root systems was conducted based on two experiments. The first experiment involved the assessment of individual plants of grasses, which up to the stage of 6-10 completely formed leaves grew in pots with 0.2 dm 3 in volume, placed in a cold frame. To keep the optimal moisture of the growth substrate (30-32% FWC), depending on the amount and frequency of precipitation the plants were sprinkled with water every 2-3 days. After growing the plants in the pots, the aboveground mass was collected, by cutting it at the height of the root neck. Roots were rinsed out with a stream of water on 0.6 and 0.4 mm mesh sieves. Larger mineral and organic impurities were removed by hand with tweezers. Plant material was dried at 60 C to obtain the air-dry mass. The second experiment involved the evaluation of development and growth of root systems for a period of two months. Grasses grew in cuvettes of 480 560 90 mm (an area of 0.268 m 2 ); in three replications for each cultivar. Depending on the germination capacity of seeds, seeding rates appropriate for individual grass species were applied in the experiment: for red and sheep s fescue 20 g m -2, and for tall fescue 30 g m -2. Cuvettes were placed in a cold frame, they were sprinkled with water every 2-3 days depending on the weather conditions, and the grown aboveground mass after the first and second months was cut at the height of 2 cm. At the end of June (the second month of growth) on each cuvette the evaluation of
Evaluation of lawn... 77 sod cover (ZA) and the general lawn aspect (OA) was carried out on the 1-9 scale [Prończuk 1993]. After the first and second months of grass growing, soil-root samples were collected from each cuvette in three replications. A ring sampler as used from the set for soil sample collection NNS made by Eijkelkamp with an area of 19.6 cm 2 and a volume of 176.6 cm 3. Roots from the samples were obtained in the same way as in the first experiment. Plant material was dried at 60 C until the air-dry weight was obtained. In each experiment the aboveground dry weight (kg m -2 ), root dry weight (kg m -2 ) and root length (m m -2 ) were determined. To determine the total root length in the experiment the computer software RadixNova, was applied, which is used for the quantitative analysis of root scans [Moraczewski 2008]. Based on the results obtained, the ratio of the dry weight of roots to the aboveground dry weight was calculated root productivity indexes K:N and the ratio of the root length to their weight, determining root density in the soil the D:K index [Sołtysik 1997]. Experiments were carried out on an artificial substrate used for establishing lawns, formed on the basis of compost humus, peat and sand, which were mixed in equal proportions. This substrate after stabilization was characterized by ph = 7.6, the content of total organic carbon (TOC) 18.7 g kg -1 and total nitrogen (Nt) 1.8 g kg -1 as well as the TOC:Nt ratio 10.3. The content of P in 100 g of air dry weight of the substrate was 12.2 mg, K 13.3 mg and Mg 8 mg. In the period of grass growth, after the first month each cuvette was fertilized with a rate of 9.56 g of multi-component fertilizer "Agrokomplex". During the experimental period from April to June the mean air temperature did not differ considerably from the mean from the long-term period and was: in April 8.5 C, in May 12.2 C and in June 17.9 C. Total precipitation during the study period was higher by 22% than the total precipitation from the long-term period and amounted to 146.8 mm, whereas the highest precipitation was recorded in May (103.7 mm). The results were subjected to statistical analysis using the program SAS. To estimate differences between the treatments, the Fisher test was applied at the level of significance P 0.05. Correlation coefficients between sod condition and the morphological features of plants were determined. RESULTS AND DISCUSSION Morphological evaluation of root system and aboveground weight Seedlings of tall fescue cultivars and one of the red fescue cultivars Adio were characterized by the largest dry weight of the aboveground part and root dry weight (Table 1). The highest total root lengths were achieved by seedlings of the red fescue cultivars Adio (155 cm) and Nimba (147 cm). The lowest values of all the studied traits were found in seedlings of sheep s fescue cultivars Noni and Mimi Similar relationships in the growth rate that occurred in individual plants were also found after the first month of growth in grasses grown in cuvettes (the second experiment). The largest root weight and their total length (Table 1) were found in tall fescue cultivars, and the smallest in sheep s fescue cultivars. The underground weight of the most red fescue cultivars remained on a balanced level of 0.05 kg m -2. However, the total root length in that species was significantly differentiated. Its lower values
78 Z. Stypczyńska, A. Dziamski, J. Schmidt were found in creeping cultivars Adio and Dark (2755-3569 m m -2 ), and higher in chewing cultivars Nimba and Rapsodia (4647-4151 m m -2 ). After the second month of plant growth in the cuvettes, the cultivars of sheep s fescue were characterized by the highest rate of increase. In spite of that, the plant weight was still the smallest and on average for the aboveground parts it amounted to 0,14 kg m -2, and for the underground parts 0.09 kg m -2. The total root length of the cultivar Mimi was equal or larger than the root length of some cultivars of red fescue and tall fescue. In tall fescue after the second month of growth increased differences were observed in biometric features between the tested cultivars. The cultivar Tarmena was characterized by significantly higher values of the root weight and length than Rahela. The results analysis showed that tall fescue cultivars after the second month of the study increased the parameters of underground parts almost twice. Similar relationships were observed in the aboveground weight. Red fescue cultivars, after the second month of growth, in spite of differentiated morphological structure of underground parts resulting from formation of creeping or chewing forms, increased the root length twice up to about 8 thousand meters. Both the underground and aboveground weight increased to a slightly higher degree (three times). Root weight of red fescue was similar to the root weight of tall fescue cultivars. The aboveground weight, however, was comparable to the weight generated from sheep s fescue cultivars. Root productivity index and index of root density in soil In the first month after sowing the roots of red fescue cultivars Adio, Nimba and Rapsodia expanded the most intensively, and the values of K:N index in them amounted to 1.25 (Table 2). The smallest root systems in relation to the aboveground weight were formed by the tall fescue cultivars Rahela (0.64) and Tarmena (0.62). In tall fescue root weight and aboveground weight remained on the balanced level and reached the K:N value equal to 1.0. After the second month of grass growth, the values of K:N index in the tall fescue cultivars increased from 0.63 to 0.78. By contrast, in the sheep s fescue and red fescue cultivars, except for the cultivar Dark, the values of K:N index decreased to a considerable degree. This indicates a more intensive growth of aboveground parts in relation the root weight., particularly in the sheep s fescue cultivars. It is notable, however, that in the cultivars Dark (Fr) and Nimba (Fr) still root dry weight predominated over dry aboveground weight. Definitely larger differentiation was found for the indexes of root density in the soil (D:K). Their highest density occurred in the first month of grass growth. This indicates an intensive increase in the total root length at generating a relatively small weight. The highest value of D:K index (on average 141.8) was achieved by the cultivars of sheep s fescue. In the other cultivars significantly lower values of D:K index were observed in tall fescue they were on average 76.1, and in red fescue 84.7. After the second month of growth, the root weight increased proportionally more intensively in relation to their length. This was expressed in a decreasing value of D:K index, which can indicate a decrease in root density in the soil. Spiss [1972] proved that the growth rate of roots is a characteristic feature for individual species and it shows a large variability under the influence of environmental conditions.
Evaluation of lawn... 79 Evaluation of lawn... 79 Table 1. Biometrical features of individual plants and grasses after the first and the second months of growing in cuvettes Tabela 1. Cechy biometryczne pojedynczych roślin i traw po pierwszym i drugim miesiącu wzrostu w kuwetach Species/cultivar Gatunek/odmiana individual plants pojedyncza roślina g Root weight Masa korzeni Root length Długość korzeni Aboveground weight Masa nadziemna first month pierwszy miesiąc kg m -2 second month drugi miesiąc kg m -2 individual plants pojedyncza roślina cm growth stage etap wzrostu first month pierwszy miesiąc m m -2 second month drugi miesiąc m m -2 individual plants pojedyncza roślina g first month pierwszy miesiąc kg m -2 second month drugi miesiąc kg m -2 Fa Rahela 0.024 0.07 0.13 140 4995 7083 0.048 0.11 0.17 Fa Tarmena 0.023 0.08 0.19 132 6453 10668 0.038 0.13 0.24 Mean Średnia 0.023 0.08 0.16 136 5724 8876 0.043 0.12 0.21 Fr Adio 0.021 0.05 0.15 155 3569 7253 0.039 0.04 0.15 Fr Dark 0.013 0.03 0.14 109 2755 7774 0.029 0.03 0.13 Fr Nimba 0.014 0.05 0.16 147 4647 7823 0.030 0.04 0.14 Fr Rapsodia 0.012 0.05 0.15 122 4151 8504 0.031 0.04 0.16 Mean Średnia 0.015 0.05 0.15 133 3781 7839 0.032 0.04 0.15 Fo Mimi 0.009 0.01 0.09 57 1314 7603 0.011 0.01 0.14 Fo Noni 0.010 0.01 0.08 71 1521 6700 0.017 0.01 0.13 Mean Średnia 0.010 0.01 0.09 64 1418 7152 0.014 0.01 0.14 Vc Wz, % 49.0 62.8 32.9 37.4 51.6 21.1 53.1 89.4 31.1 LSD0.05 NIR0,05 A 0.008 0.02 0.03 7 240 316 0.003 0.04 0.01 LSD0.05 NIR0,05 B 0.004 0.01 0.01 8 270 377 0.003 0.02 0.01 Wz Vc variation coefficient współczynnik zmienności LSD0,05 NIR0,05 A for cultivars dla odmian LSD0,05 NIR0,05 B for species dla gatunków
80 Z. Stypczyńska, A. Dziamski, J. Schmidt 80 Z. Stypczyńska, A. Dziamski, J. Schmidt Table 2. Ratio of the dry weight of roots to the dry weight of the aboveground part (K:N indexes) and the root density in soil (D:K indexes) in individual plants and grasses after the first and the second month of growing in cuvettes Tabela 2. Stosunek suchej masy korzeni do suchej masy części nadziemnej (współczynniki K:N) i zagęszczenia korzeni w glebie (D:K) u pojedynczych roślin oraz traw po pierwszym i drugim miesiącu wzrostu w kuwetach Species/cultivar Gatunek/odmiana individual plants pojedyncza roślina K:N D:K first month pierwszy miesiąc growth stage etap wzrostu second month drugi miesiąc individual plants pojedyncza roślina first month pierwszy miesiąc Fa Rahela 0.50 0.64 0.76 5.83 71.4 54.5 Fa Tarmena 0.61 0.62 0.79 5.74 80.7 56.1 Mean Średnia 0.55 0.63 0.78 5.79 76.1 55.5 Fr Adio 0.54 1.25 1.00 7.38 71.4 48.4 Fr Dark 0.45 1.00 1.08 8.38 91.8 55.5 Fr Nimba 0.47 1.25 1.14 10.50 92.9 48.9 Fr Rapsodia 0.39 1.25 0.94 10.17 83.0 56.7 Mean Średnia 0.46 1.19 1.03 9.11 84.7 52.3 Fo Mimi 0.82 1.00 0.64 6.33 131.4 84.5 Fo Noni 0.59 1.00 0.62 7.10 152.1 83.8 Mean Średnia 0.71 1.00 0.63 6.71 141.8 84.1 Vc Wz, % 76.2 48.0 39.6 96.8 62.4 33.7 second month drugi miesiąc LSD0.05 NIR0,05 A 0.11 0.11 0.07 2.45 16.2 4.4 LSD0.05 NIR0,05 B 0.11 0.11 0.07 2.36 15.5 4.1 for explanations, see Table 1 objaśnienia pod tabelą 1
Evaluation of lawn... 81 Red fescue forms the root system mostly in the surface layers and it generates sod by means of rhizomes and runners, as organs which accumulate storage material [Stewart et al. 2004]. Tall fescue form a deep and strongly developed root system and consequently, it tolerates well the conditions of water deficit [Stuczyńska and Stuczyński 1993, Wilman et al. 1998]. By contrast, sheep s fescue develops roots mostly in the surface layers of soil and at the same time it shows little water requirement, which is mainly connected with the specific xeromorphic structure of leaves [Golińska 2002, Żurek 2006]. The above relationships can explain the obtained differences in the size of root weight, and hence the calculated values of K:N and root massiveness in the studied grass species and cultivars. Sod condition Evaluation of sod condition carried out after the second month of grass growing (Table 3) showed that the values of the sod cover degree (ZA) and the general sod aspect (OA) were similar and indicated a relatively good conditions of plants. Values of the evaluation of sod cover (ZA) were within the range from 5.0 for the cultivar Dark (Fr) to 7.8 for the cultivar Tarmena (Fa). The evaluation of the general lawn aspect (OA), in turn, ranged from 4.7 for the cultivar Dark (Fr) to 7.1 for the cultivar Tarmena (Fa). To estimate the connections between sod conditions and the studied grass morphological features, a correlation analysis was conducted (Table 3). Significant correlations of sod cover and the general aspect of lawn with the studied morphological features refers mostly to the species which are distinguished by the distinctiveness of diagnostic features, this is the cultivars of tall fescue and sheep s fescue. In the cultivars of red fescue only Adio stands out, where the morphological structure of roots has a considerable effect on the general aspect of lawn. Few connections of sod conditions with grass morphological traits in the conducted experiment may result from a short period of formation of the root systems. According to the studies by Sytnik et al. [1977] and Gibson [2009], the roots play an important role in forming the aboveground weight. CONCLUSIONS 1. Variability of morphological structure of roots in species and cultivars of lawn grasses of the genus Festuca occurs already at the stage of seedlings. 2. Of the evaluated grass species, tall fescue cultivars were characterized by the most balanced morphological features of roots, and they showed the highest growth rate of plants. 3. Red fescue cultivars generated the largest root system in relation to the aboveground mass of the tested grasses at each stage of the study. 4. In both tested tall fescue cultivars proportions between the underground and aboveground parts as well as between the total length of roots and their mass were similar, but the cultivar Tarmena was characterized by the highest values of the evaluated traits. 5. Determination of total root length and indexes of productivity and root density in soil can be a good indicator determining the morphological structure of grasses and their commercial usefulness.
82 Z. Stypczyńska, A. Dziamski, J. Schmidt Evaluation of lawn... 82 Table 3. Sod condition depending on the sod cover degree and the general aspect after the second month of grasses growing in cuvettes. Values of the correlation coefficients between the sod cover and the general aspect with the features of grasses after the second month of grasses growing in cuvettes Tabela 3. Kondycja darni w oparciu o ocenę stopnia zadarnienia (ZA) i ogólnego aspektu (OA) po drugim miesiącu wzrostu traw w kuwetach. Wartości współczynników korelacji zadarnienia i ogólnego aspektu z cechami traw po drugim miesiącu wzrostu traw w kuwetach Species/ cultivar Gatunek/odmiana Sod condition Kondycja darni Sod cover zadarnienie Morphological characters Cechy morfologiczne Coefficients Współczynniki aboveground weight masa nadziemna root weight masa korzeni root lenght długość korzeni K:N D:K Correlation coefficients of evaluated parameters Współczynniki korelacji ocenianych parametrów Fa Rahela 5.7-0.83* -0.83* -0.41 0.82* 0.21 Fa Tarmena 7.8-0.33-0.84* -0.36 0.24 0.12 Fr Adio 5.3 0.01-0.72* -0.72* 0.01 0.84* Fr Dark 5.0 0.48 0.24-0.36-0.24 0.24 Fr Nimba 6.5-0.42-0.21 0.03 0.21 0.02 Fr Rapsodia 5.8 0.72* -0.24 0.04-0.59-0.59 Fo Mimi 6.5 0.36-0.12-0.12 0.36-0.24 Fo Noni 6.2 0.48 0.59-0.59 0.24-0.84* general aspect ogólny aspekt Correlation coefficients of evaluated parameters Współczynniki korelacji ocenianych parametrów Fa Rahela 5.3-0.83* -0.83* 0.41 0.83* 0.21 Fa Tarmena 7.1 0.22-0.14-0.18 0.25 0.09 Fr Adio 5.1 0.09-0.73 0.67-0.76 0.79* Fr Dark 4.7 0.05 0.41-0.21 0.06 0.41 Fr Nimba 6.2-0.41-0.21 0.00 0.21 0.01 Fr Rapsodia 5.7 0.36-0.48 0.35-0.84-0.12 Fo Mimi 6.2 0.21 0.21-0.21 0.21-0.62 Fo Noni 5.5 0.41 0.62-0.20 0.21-0.62 * significance of correlation coefficient at P = 0.05 istotność współczynnika korelacji dla P = 0,05
Evaluation of lawn... 83 REFERENCE Domański P., 1998. Metodyka badań wartości gospodarczej odmian (WGO) roślin uprawnych. Rośliny rolnicze. Trawy Gazonowe [Methods for study of cultivar economic value of cultivated plants. Agricultural crops. Lawn grasses]. COBORU Słupia Wielka. Dziamski A., Stypczyńska Z., Żurek G., Łabędzki L., Długosz J., 2007. Observations of root system development and dynamics of root: shoot ratio of selected turf grass varieties and breeding lines grown in different soil conditions. Plant Breed. Seed Sci. 55, 76-88. Gibson D.J., 2009. Grasses and Grassland Ecology. Oxford University Press. Golińska B., 2002. Ocena przydatności wybranych odmian hodowlanych Festuca rubra i Festuca ovina do ekstensywnego użytkowania trawnikowego [Evaluation of usefulness of some Festuca rubra and Festuca ovina cultivars for extensive lawn use]. Prz. Nauk. Inż. Kształt. Środ. 24, 123-129 [in Polish]. Jankowski K., Jankowska J., Sosnowski J., 2012. Ocena zadarnienia muraw trawnikowych założonych na bazie śmiałka darniowego [Evaluation of sod cover of lawn turfs established on the basis of turf hairgrass]. Fragm. Agron. 29(2), 52-59. Harkot W., Czarnecki Z., 1998, Dynamika wydłużania systemu korzeniowego siewek polskich odmian traw gazonowych [Dynamics of root system lengthening in seedlings of Polish lawn grass cultivars]. Ann. Univ. Mariae Curie-Skłodowska, Sectio E, Agricultura 20, 177-185 [in Polish]. Harkot W., Czarnecki Z., 1999. Przydatność polskich odmian traw gazonowych do zadarnienia powierzchni w trudnych warunkach glebowych [Usefulness of Polish cultivars of lawn grasses for zadarnienia powierzchni in difficult soil conditions]. Fol. Univ. Agric. Stetin., Agricultura 75, 117-120 [in Polish]. Moraczewski I., 2008. RadixNova. Wydawca cortexnova (www.cortexnova.com), Bydgoszcz [in Polish]. Prończuk S., 1993. System oceny traw gazonowych [System of evaluation of lawn grasses]. Biul. IHAR 225, 239-257 [in Polish]. Prończuk S., Prończuk M., Żyłka D., 1997. Metody syntetycznej oceny wartości użytkowej traw gazonowych [Methods for synthetic evaluation of lawn grass commercial value]. Zesz. Probl. Post. Nauk Rol. 451, 125-133 [in Polish]. Sołtysik A., 1997. Wpływ zabiegów agromelioracyjnych (orki agromelioracyjnej) na rozmieszczenie masy i długości korzeni jęczmienia jarego w madzie ciężkiej [Effect of land reclamation (agro-melioration ploughing) on distribution of spring barley root weight and length in heavy alluvial soil]. Wiad. Inst. Mel. Użyt. Ziel. XIX(2), 79-91 [in Polish]. Spiss L., 1972. Wycena pojedynków traw i motylkowatych drobnonasiennych we wczesnych fazach rozwoju [Evaluation of individual plants of grasses and small-seeded legumes at early developmental stages]. Hod. Rośl. Nasien. 2 [in Polish]. Stewart J.R., Kjelgren R., Johnson P.G., Kuhns M.R., 2004. Soil-water-use characteristics of precision-irrigated buffalograss and kentucky bluegrass. Applied Turfgrass Science, Plant Management Network, http://www.plantmanagementnetwork.org/pub/ats/research/2004/water Stuczyńska J., Stuczyński M., 1993. Porównanie systemów korzeniowych oraz masy nadziemnej kostrzewy trzcinowej, kupkówki pospolitej i stokłosy uniolowatej przy różnej częstości koszenia [Comparison of root systems and aboveground weight in tall fescue, cocksfoot grass and unioloid bromegrass at different cutting frequency]. Biul. IHAR 188, 139-142 [in Polish]. Sytnik K.M., Kniga N.M., Musatienko L.I., 1977. Fizjologia korzenia [Root physiology]. PWRiL Warszawa [in Polish]. Wilman D., Gao Y., Leitch M.H., 1998. Some differences between eight grasses within the Lolium-Festuca complex when grown in conditions of severe water shortage. Grass and Forage Sci. 53, 57-65. Żurek G., 2006. Reakcja traw na niedobory wody metody oceny i ich zastosowanie dla gatunków trawnikowych [Response of grasses to water deficit methods of evaluation and their use for lawn species]. Monogr. i Rozpr. Nauk IHAR 25 [in Polish].
84 Z. Stypczyńska, A. Dziamski, J. Schmidt OCENA ODMIAN TRAW GAZONOWYCH Z RODZAJU Festuca W POCZĄTKOWYM ETAPIE WZROSTU W OPARCIU O BADANIA MORFOMETRYCZNE ICH SYSTEMÓW KORZENIOWYCH Streszczenie. Badania prowadzono w 2010 roku na terenie Ogrodu Botanicznego IHAR w Bydgoszczy. W dwóch doświadczeniach oceniano osiem odmian gazonowych należących do trzech gatunków traw z rodzaju Festuca: F. arundinacea (Schreb.), F. rubra (L.), F. ovina (L.). Doświadczenie pierwsze dotyczyło oceny pojedynczych roślin, które do fazy 6-10 dobrze wykształconych liści rosły w doniczkach. W drugim doświadczeniu przez okres dwóch miesięcy trawy rosły w kuwetach ustawionych w nieogrzewanym inspekcie. W każdym eksperymencie określano masę korzeni, ich długość i masę nadziemną traw. Obliczono współczynniki produkcyjności korzeni i zagęszczenia korzeni w glebie. Dokonano oceny trawnikowej, uwzględniając ogólny aspekt i stopień zadarnienia trawnika. Największe parametry ocenianych cech stwierdzono u odmian Festuca arundinacea. Najmniejsze wartości wykazały odmiany Festuca ovina, które charakteryzowały się największym tempem zwiększania masy i długości korzeni. Odmiany Festuca rubra ze względu na kępową lub rozłogową budowę masy podziemnej wykazały duże zróżnicowanie pod względem analizowanych cech i obliczonych współczynników. Słowa kluczowe: długość korzeni, kondycja darni, masa korzeni, pojedynki traw Accepted for print Zaakceptowano do druku: 19.09.2012