Vol. 5 (1996): 461^173. Yields, plant characteristics, total N and fibre composition of timothy cultivars grown at two latitudes H. Tapani Kunelius Research Centre, Agriculture and Agri-Food Canada, Charlottetown, Prince Edward Island, Canada. CIA 7MB Pertti Pärssinen Boreal Plant Breeding, Myllytie 10, FIN-31600 Jokioinen, Finland Seppo K. Pulli Agricultural Research Centre ofFinland, Institute of Crop and Soil Science, FIN-31600 Jokioinen, Finland Timothy (Phleum pratense L.) cultivars of southern (45°N) and northern (>6O°N) origin were grown in Charlottetown, Prince Edward Island, Canada (46° N) and Jokioinen, Finland (61° N) in two years. Timothy was harvested twice a season and nitrogen applied at 100 or 150 kg/ha. Dry matter yields were higher in Charlottetown than in Jokioinen and northern cultivars outyielded southern cultivars. Nitrogen at 150 kg/ha increased total yields an average of 1.4 t/ha over the 100 kg N/ha rate. The stems and panicles of timothy were longer in Charlottetown. Northern cultivars had longer panicles. The leaf content of cultivars ranged from 139 to 230 g/kg. Northern cultivars had greater N concen- trations (22.1 g/kg) in cut 2 than southern timothies (19.7 g/kg). Concentrations of neutral detergent fibre (NDF) and acid detergent fibre (ADF) in cut 1 were lower in Jokioinen, In conclusion, northern cultivars performed well in Charlottetown but there were differences in yield stability among culti- vars. Nutritional quality of timothy cultivars varied among the sites and the significance of differenc- es in NDF and ADF in relation to animal performance require further study. Key words', fibre content, leaves, nitrogen fertilizer, panicle, Phleum pratense L., stem ntroduction Timothy (Phleum pratense L.) is a widely grown forage grass in the humid, microthermal regions including northeastern part of north America and Nordic countries. Reasons for tim- othy’s importance include its adabtability as it can be grown successfully under a wide range of soil and climatic conditions. Timothy is win- terhardy and under proper management it can persist for several years in its area of adaptation (Pulli 1980, Bélanger et al. 1989). Timothy is usually grown for hay or silage for on-farm feed- ing and it is also grown for export markets which may have specific requirements for hay quality. Previous studies on timothy cultivars origi- nating from different latitudes have dealt with © Agricultural and Food Science in Finland Manuscript received October 1995 461 AGRICULTURAL AND FOOD SCIENCE IN FINLAND https://www.c-info.fi/en/info/?token=4TZBr-ntEGHZ6XWp.UtvMMb2Ft3OpNmCr6BdwOw.NiL-M2HHfk9_sOupqjDkxJx-O03nIERhL5k82xhaOz3BY9oF7UuzO3-WErqsYpuSaU2eG8wyZJG9-hiBsXm64XyxVhQJUFIHzKywh_cxveCLoxjrBx5sCuEKm_vQcg9xlC57s-1PSgV4Vz5P2VdyHB8JLBJi1rsEAHL8Q6J0Pk3tdsb1vNfQ_aq4FP3Oe_dogSKGtYwy3YETPy-fkByRncqjhvNZFIR2UFkcGNW3TjqWzAv54kL6UFqlSxyyDd0PmFPmcjABEi0qpkQ0zaGkJzS7G5STWEskImQELad5Yi-rTC2U-jouIPbvO5isstn9 Kunelius, H.T el al. Yields, plant characteristics, total N andfibre composition oftimothy cultivars plant growth, digestibility of dry matter, persist- ence and plant characteristics. In Scotland (55.5°N), Hay (1989) noted that timothy culti- vars originating from high (>6l°N) latitudes had lower annual dry matter production than culti- vars from low latitude (52°N). Winter survival of timothy in Alaska (61.6°N) was the best for cultivars originating from northern, high latitude regions in the Nordic countries (Klebesadel and Helm 1986). Schjelderup et al. (1994) suggest- ed that these high latitude cultivars of timothy are genetically heterogenous for genes govern- ing winter survival. Deinum et al. (1981) found that contrasting timothy cultivars, harvested at the same morphological stage, were more digest- ible grown at high latitudes than those grown at lower latitudes.The digestibility of early matur- ing timothy cultivars tends to be greater than that of late maturing cultivars at the same morpho- logical stage (Koch 1976, Mika 1983). Several factors, such as nitrogen fertilization and harvest management, influence the growth and composition of timothy. Fertilizing timothy with nitrogen increases dry matter production and tissue N concentration (Kunelius et al. 1976, Hunt et al. 1979, Kline and Broersma 1983, Kunelius et al. 1987, Lindgren and Lindberg 1988, Bélanger et al. 1989). A two-cut system for timothy, with harvest at full heading, result- ed in high yields and good persistence but N concentration and dry matter digestibility were low in Atlantic Canada (Kunelius et al. 1976, Kunelius and Mcßae 1987). In Northern Swe- den (64°N) Lindgren and Lindberg (1988) con- cluded that timothy harvested two to four days after heading and fertilized with 100 kg N/ha in spring resulted in herbage with 11.5 MJ ME/kg and 160 g CP/kg in organic matter. In recent years demand for timothy hay for various uses including export markets has in- creased. Management systems including timely harvesting and adequate fertilization with nitro- gen are required for producing timothy that meets specific criteria for hay quality and ap- pearance. Location can have a significant influ- ence on timothy cultivars (Surprenant et al. 1993) but relatively little is known about plant charac- teristics and composition of timothy cultivars grown in contrasting environments. According- ly, the objective of this study was to determine, at two latitudes, the yields, plant characteristics, fibre composition and total N concentration of timothy cultivars of diverse origin and maturi- ties fertilized at two rates of nitrogen. Material and methods Experiments were established in Charlottetown, Prince Edward Island, Canada (46°N), and Jokio- inen, Finland (61 °N). The growing season in Prince Edward Island is about 180 days (>5°C) and it is characterized by a wet, cool spring and fall, and a warm, moist summer with occassion- al periods of drought (Table 1). The soil in Char- lottetown was fine sandy loam, an Orthic Humo- Ferric Podzol, with a pH of 6.4. This soil has a poorly structured fragipan-like subsoil below 60 cm depth which impedes drainage. The growing season in Jokioinen is about 150 days (>s°) with a cool and dry spring, a moist and warm sum- mer and a cool autumn (Table 1). The soil in Jokioinen was sandy clay with a pH of 6.5. In Charlottetown N, P and K were applied at 25, 44 and 83 kg/ha before seeding in mid-June 1991 and in mid-August at 45, 7 and 37 kg/ha, respectively. In Jokioinen the respective N, P and K rates were 48, 21 and 39 at the timeof sowing in mid-July 1991. Timothy was sown at 12 kg/ha with small- plot drill (Wintersteiger, Reid, Austria). Weeds were controlled by clipping in mid-August. The plots measured 1.5 x 5.0 m. The experimental design was a factorial arranged as a randomized block with four replications. The timothy cultivars and their origins are listed in Table 2. In early May of both production years, P and K were applied at 35 and 66 kg/ha, respectively, in Charlottetown. After cut 1, K was applied at 66 kg/ha. In Jokioinen the respective P and K rates were 45 and 85 kg/ha in May and 35 and 462 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^73. Table I. Mean monthly temperatures and total precipitation during the first (1992) and second (1993) production years in Charlottetown, Prince Edward Island, Canada and Jokioinen,Finland. Mean temperature, °C Precipitation, mm Charlottetown Jokioinen Charlottetown Jokioinen Year 1 Year 2 30 yr Year 1 Year 2 30 yr Year 1 Year 2 30 yr Year 1 Year 2 30 yr mean mean mean mean April 1.3 2.8 2.7 1.3 3.3 2.4 49 147 88 48 29 31 May 9.1 8.0 9.2 11.4 13.6 9.4 60 102 90 7 7 35 June 14.2 13.8 14.8 15.7 11.4 14.3 81 99 88 25 56 47 July 15.8 16.3 18.8 16.0 15.6 15.8 162 89 78 47 107 80 August 18.5 18.3 18.4 14.3 12.9 14.2 160 28 90 107 136 83 September 14.9 13.7 14.0 11.3 5.7 9.4 32 70 92 59 13 65 October 7.5 6.0 8.6 -0.6 3.0 4.7 146 162 112 64 51 58 November 0.9 2.2 3.1 -1.8 -3.6 -0.5 94 93 115 63 3 55 66 kg/ha after cut 1. Nitrogen, as ammonium nitrate, was applied at two rates: 60 in spring and 40 kg/ha after cut 1 (low N) or 90 in spring and 60 kg/ha after cut 1 (high N) at the two sites. A day before harvest, twenty random stems were cut from each plot for determining panicle length and stem length of timothy cultivars. Green leaves (blade), stems and dead matter were separated and dried at 80°C. Timothy in the pri- mary (cut 1) and secondary growth (cut 2) was harvested with a Haldrup 1500 forage plot har- vester (J.Haldrup, Lpgstor, Denmark) at the growth stage R 2 - R 3 (Moore et al. 1991) when the panicle had emerged. The dates of harvest are given in Table 3. Samples of chopped forage were dried at 90°C to constant weight in a forced air drier. A separate sample was freeze dried and ground through a 1-mm screen for tissue analy- ses. Total nitrogen concentration was determined by the combustion method (Association of Offi- cial Analytical Chemists 1989). Neutral and acid detergent fibres were sequentially fractionated using the procedure outlined by Van Soest (1982). Table 2. Timothy cultivars and their regions of origin. Table 3.Mean harvest dates of timothy cultivarsat full head- ing stage in the two production years. Cultivar Latitude, °N Region Year Cut Cultivar Location Southern Climax group Charlottetown Jokioinen45 Ontario, Canada Quebec, Canada Minnesota. USA Minnesota, USA Ontario, Canada Minnesota, USA Po Valley, Italy Minnesota, USA Drummond Glenmor 43 1 1 E t 29 June 29 June 45 L 8 July 29 June Itasca 45 2 E 27 August 4 September Richmond Timfor 44 L 4 September 4 September 45 2 1 E 3 July 23 June Toro 45 L 9 July 23 June Winmor 45 2 E 25 August 9 September Northern L 7 September 9 September Alma 61 Finland Sweden Iceland Finland tE = Itasca, Richmond, Timfor, ToroBottnia II 64 L =Climax, Drummond, Glenmor, Winmor, Alma, BottniaKorpa Tiiti 65 11, Korpa, Tiiti60 463 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Kunelius, H.T. et al. Yields, plant characteristics, totalN andfibre composition oftimothy cultivars Table 4. Mean dry matter yields (t/ha) of timothy cultivars, yield differences between years and effect of nitrogen fertilizer on yields. Cultivar Cut I Cut2 Charlottetown Jokioinen Charlottetown Jokioinen Yield Difference t Yield Difference Yield Difference Yield Difference Southern Climax 7.1 -2.6 2.7 1.7 2.5 1.7 3.0 0.2 3.4 -0.3 2.72.2 Drummond Glenmor 6.9 -1.0 3.13.2 7.1 -1.7 2.1 1.8 3,6 O 2.93.0 Itasca 5.91.4 2.5 1.5 2.8 1.8 2.4 1.3 2.4 1.3 2.4 1.7 3.5 -0.3 3.23.4 Richmond Timfor 5.40.8 3.7 -1.0 3.53.5 5.61.4 3.4 -0.1 3.13.2 Toro 5.10.5 3.4 -0.4 3.43.5 Winrnor 6.4 0 3.10.3 3.03.1 Northern Alma 7.6 -2.7 3.3 1.5 3.2 1.5 2.6 1.7 3.5 1.1 2.7 1.6 3.1 0 2.3 1.7 Bottnia II 6.9 -1.9 3.1 -0.3 2.6 0.1 2.9 0.1 3.2 -0.1 0.14 0.23 2.5 1.7 Korpa 8.0 -4.2 1.7 1.2 2.9 2.1 2.9 2.7 0.14 0.23 Tiiti 7.1 -1.23.5 1.1 Mean 6.6 -0.92.7 1.6 sem, n= 8, df= 138 0.220.48 0.220.48 N rate, kg/ha 100 6.2 -0.82.5 1.3 150 6.9 -1.02.9 1.8 sem, n = 48, df= 138 0.090.19 0.090.19 2.7 -0.6 3.8 0.3 0.06 0.09 2.52.4 3.22.9 0.060.09 t Minus (-) denotes lower yield in year 2 than year 1. Analysis of variance was performed on two- year combined data for each cut. Selected or- thogonal contrasts for comparing selected culti- vars were calculated using the statistical program GENSTAT 5 (Genstat 5 Committee 1993). Results Selected contrasts were calculated and reference is made to significant (P<0.05) site effects be- tween Charlottetown and Jokioinen and for cul- tivars of southern vs northern origin. The dry matter (dm) yields of cut 1 were greater in Charlottetown than in Jokioinen (Ta- ble 4). The yields in Jokioinen were also con- siderably greater in year 2 than year 1. Timothy cultivars of northern origin outyielded those of southern origin in cut 1 while in cut 2 the re- verse was true. There were significant site x cul- tivar interactions for dry matter production. In cut I, dry matter yields among the cultivars ranged from 5.1 to 8.0 t/ha in Charlottetownand from 2.1 to 3.5 t/ha in Jokioinen. Dry matter yields of cut 2 in Charlottetown were from 2.6 to 3.7 t/ha and in Jokioinen from 1.7 to 3.5 t/ha. Yield differences in cut 1 between years varied in Charlottetown; dry matter yield of Winrnor was 6.4 t/ha in both years while Korpa, Alma and Climax yielded 2.6 to 4.2 t/ha less in year 2 than 1. In Charlottetown yield differences of cultivars in cut 2 were small but in Jokioinen yields of cut 2 were 1.2 to 3.5 t/ha greater in year 2 than year 1. The dry matter yields of cuts 464 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^73. Table 5. Mean length and differences in length of panicle and stem of timothy at the time of cut 1. Cultivar Panicle, mm Stem, cm Charlottetown Jokioinen Charlottetown Jokioinen Length Difference t Length Difference Length Difference Length Difference Southern Climax 71 6 51 1 83 5 64-1 Drummond 71 5 48 10 80 7 57 -1 Glenmor 64 II 44 -2 85 -1 60 -4 Itasca 64 2 41 4 77 3 59 0 Richmond 64 7 41 5 79 -1 65 9 Timfor 62 16 42 0 75 8 60 0 Toro 61 17 40 3 80 4 64 3 Winmor 69 9 44 1 83 9 59-4 Northern Alma 72 7 53 11 82 6 63 1 Bottniall 65 9 48 10 84 3 64 0 Korpa 69 5 45 7 77 6 54 -5 Tiiti 75 0 51 8 79 6 64-1 Mean 67 8 46 5 81 5 61 0 sem, n= 8, df= 138 2.03.3 2.03.3 1.12.3 1.12.3 N rate, kg/ha 100 64 6 45 5 81 5 61 0 150 71 10 46 5 80 4 61 0 sem, n = 48, df= 138 0.81.3 0.81.3 0.40.9 0.40.9 t Minus (-) denotes shorter length in year 2 than year I. 1 and 2 were 0.4 to 1.1 t/ha greater for the 150 than 100 kg/ha rate of N in two sites (Table 4). Yield increase, due to applied N at 150 kg/ha over 100 kg/ha rate, was greater in Charlotte- town than in Jokioinen. The panicles of timothy were longer in Char- lottetown than in Jokioinen (Table 5). Tiiti had the longest panicles and Toro the shortest pani- cles. The largest year to year difference of 17 mm in panicle length was for Toro in Charlotte- town. Northern cultivars of timothy had slightly longer panicles at 59 mm than southern culti- vars at 55 mm. There was a significant site x N rate interaction; panicles were 7 mm longer in Charlottetown, and only 1 mm longer in Jokio- inen for the 150 than 100 kg N/ha rate. The stems of timothy in cut 1 were, on aver- age, 20 cm taller in Charlottetown than in Jokio- inen (Table 5 ). Yearly differences in stem lengths of cultivars were small. There was a significant site x cultivar interaction with Drummond, Glen- mor, Winmor and Korpa showing greater differ- ences in stem length between the sites than oth- er cultivars. Rates of nitrogen had little effect on the stem length. Mean leaf content of timothies was similar in Charlottetown and Jokioinen (Table 6). Leaf content among cultivars varied less in Jokioin- en than in Charlottetown where the leaf content ranged from 230 g/kg for Timfor to 139g/kgfor Alma. Difference in leaf content between the years was least for Korpa and largest for Tim- for. Nitrogen rate did not affect leaf content, Dead material content of cultivars in Char- lottetown ranged from a low of 23 to a high of 48 g/kg for Richmond and Alma, respectively 465 Kunelius, H.T et al. Yields, plant characteristics, totalN andfibre composition oftimothy cultivars Table 6. Mean leaf and dead matter contents (g/kg) of timothy cultivars at cut 1 and differences in the contentsbetween the years. JokioinenCultivar Charlottetown Charlottetown Leaves Difference t Leaves Difference Dead matterDifference Southern Climax 146 4 148 -16 42 -18 Drummond 167 -11 191 -40 43 -21 Glenmor 162 4 165 -12 39 -12 Itasca 199 -57 186 -30 40 12 Richmond 199 -22 171 -50 23 -13 Timfor 230 -78 170 -39 34 19 Toro 204 -29 178 -60 24 2 Winmor 182 -17 179 -1 33 -13 Northern Alma 139 -5 143 -35 48 -21 Bottnia 11 142 -I 162 -31 40 -18 Korpa 151 I 156 -2 46 -24 Tiiti 153 1 160 -42 37 -16 Mean 167 -18 167 -30 37 -10 sem, n = 8, df = 138 7.9 12.0 7.9 12.0 3.0 5.6 N rate, kg/ha 100 172 -16 167 -28 37 -9 150 173 -20 168 -32 37 -11 sem, n = 48,df= 138 3.2 4.9 3.2 4.9 1.2 2.3 t Minus (-) denotes lower content in year 2 than year 1. (Table 6). Dead material of most cultivars was lower in the second year. Southern timothies had lower dead material content (35 g/kg) than north- ern cultivars (43 g/kg). The N concentrations of most timothy culti- vars in cuts 1 and 2 were considerably greater in Jokioinen than in Charlottetown (Table 7). In cut 1, total N concentration of timothy cultivars ranged from 9.5 to 12.7 g/kg in Charlottetown and from 13.4 to 16.8 g/kg in Jokioinen. Total N concentrations in cut 2 were from 13.1 to 17.1 g/kg in Charlottettown while in Jokioinen the concentrations were from 18.8 to 26.4 g/kg. To- tal N in cut 1 was similar in both years. In cut 2 there were, however, large differences in Jokio- inen where total N concentrations were greater in year 1. Northern cultivars had greater total N concentrations (22.1 g/kg) in cut 2 than south- ern timothies (19.7 g/kg). Significant site x N rate interaction in cut 1 was due to greater in- crease in the N concentration between 100 and 150 kg N/ha rates in Charlottetown than in Jokioinen while in cut 2 the reverse occured. Neutral detergent fibre (NDF) concentrations oftimothy cultivars in cut 1 were lower in Jokioi- nen than in Charlottetown while in cut 2 the reverse was true (Table 8). In cut 1, Richmond and Toro were lowest in NDF at both sites. It is also noted that in Jokioinen the southern culti- vars in cut I were lower in NDF than northern timothies. In cut 2, there were large differences in NDF of cultivars in Charlottetown where northern cultivars were lowest in NDF. Nitro- gen at 150kg/ha, compared with 100 kg/ha rate, decreased NDF in cut 1 and increased in cut 2 in Charlottetown but not in Jokioinen. 466 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^73. Table 7. Mean nitrogen concentration (g/kg) of timothy cultivars in cuts 1 and 2 and differences in N concentrations be- tween the years. Cultivar Cut 1 Cut 2 Charlottetown Jokioinen Charlottetown Jokioinen N cone. Difference t N cone. Difference N cone. Difference N cone. Difference Southern Climax 10.2 -2.1 16.8 3.5 15.7 -0.7 15.0 0.6 15.7 -1.1 13.4 -1.0 15.3 -0.9 14.6 -2.2 14.6 -3.4 14.6 -3.8 13.8 -3.3 14.1 -3.1 14.4 -0.2 14.3 -4.2 14.4 -1.0 21.1 -14,1 19.9 -17.4 18.8 -14.9 19.7 -17.7 18.5 -17.1 18.8 -14.3 20.2 -18.3 Drummond 11.3 -0.3 Glenmor 10.6 -0.710.6 -0.7 Itasca 12.5 -1.9 Richmond 12.7 -1.7 Timfor 12.5 -2.8 Toro 12.6 -1.6 Northern Winmor 10.3 0.8 14.5 0 14.9 -0.7 15.2 -2.2 16.0 1.1 14.7 1.0 15.2 -0.2 0.44 0.95 13.1 -3.7 14.9 -4.7 15.1 -4.0 17.1 -3.2 14.6 -3.9 14.6 -3.2 0.44 0.85 19.1 -15.5 22.6 -15.8 23.0 -17.4 26.4 -17.3 21.0 -14.8 20.8 -16.2 0.440.85 Alma 10.8 -0.4 Bottnia II 10.5 -0.5 Korpa 10.8 -1.0 Tiiti 9.5 -0.4 Mean 11.2 -1.1 sem, n = B,df= 138 0.44 0.95 N rate, kg/ha 100 10.2 -1.814.6 -0.714.3 -3.819.6 -15.5 150 12.2 -0.315.7 0.314.9 -2.622.0 -16.9 sem, n = 48, df= 1380.180.36 0.180.36 0.180.35 0.180.35 t Minus (-) denotes lower concentration in year 2 than year 1. Acid detergent fibre (ADF) of timothy in cut 1 was lower in Jokioinen than in Charlottetown (Table 9). Differences among cultivars within sites and between the years were up to 38 g/kg. In cut 2, ADF of Toro and Timfor varied more among the sites than ADF of other cultivars. Northern cultivars were consistently low in ADF in both sites. Hemicellulose concentration of timothy was greater in Jokioinen than in Charlottetown (Ta- ble 10). The rates of N had little effect on hemi- cellulose concentration in timothy. Toro in cut 1 was low in hemicellulose in both sites while Drummond and Tiiti were high in hemicellulose. In cut 2, Toro and Alma were the lowest in hemi- cellulose in Charlottetown. In Jokioinen the four northern cultivars were higher in hemicellulose than southern timothies. Discussion Timothy is adapted to the growing conditions of microthermal regions such as Atlantic Canada and Nordic countries. In this study all timothy cultivars persisted in Charlottetown and Jokioi- nen where the overwintering conditions were quite severe with minimum air temperatures ex- ceeding -20° C. Under harsh overwintering con- ditions in Alaska, Klebesadel and Helm (1986) found that wintersurvival of timothy was corre- lated with the latitude of cultivar origin, with northernmost cultivars being superior to those of more southern origin. In our study there were, however, differences in the dry matter yields of timothy cultivars; dry matter yields of the pri- mary growth were much greater in Charlottetown 467 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Kunelius, H.T et al. Yields, plant characteristics, totalN andfibre composition of timothy cultivars Table 8, Mean neutral detergent fibre (NDF) concentration (g/kg) of timothy cultivars in cuts 1 and 2 and differences in NDF between the years. Cultivar Cut I Cut 2 Charlottetown Jokioinen Charlottetown Jokioinen NDF Difference t NDF Difference NDF Difference NDF Difference Southern Climax 692 53 613 22 594 22 604 14 633 -4 Drummond 703 Glenmor 697 54 637 58 14 637 -19 36 609 -14 616 29 621 28 629 -31 Itasca 690 44 608 37 28 633 -16 Richmond 680 34 597 27 628 21 628 28 625 31 632 -56 Timfor 696 50 612 6 641 -16 Toro 679 40 586 13 31 631 -14 Winmor 696 33 614 -5 605 11 638 -46 Northern Alma 684 49 630 54 578 14 643 -14 Bottnia II 674 62 619 63 580 15 629 -21 Korpa 695 57 617 38 577 8 619 -33 Tiiti 689 57 625 58 570 0 644 1 Mean 690 47 614 30 602 18 635 -22 sem, n =B,df= 138 4.6 8.6 4.6 8.6 5.0 10.5 5.0 10.5 N rate, kg/ha 100 697 47 615 29 590 0 633 -32 150 683 48 612 31 615 37 637 -13 sem, n =48, df = 138 1.9 3.5 1.9 3.5 2.1 4.3 2.1 4.3 t Minus (-) denotes lower concentration in year 2 than year 1. than in Jokioinen. The dry matter yields in Jokio- inen were also low in comparison with annual timothy yields of over 9 t/ha in trials conducted in several sites in southern Finland (Niemeläi- nen and Rinne 1992). A likely reason for low dry matter yields in Jokioinen was low precipitation, particularly, in the spring of year 1 (Table 1) which reduced the growth of timothy. In year 2, rainfall in May was again low in Jokioinen and temperature in June was below normal resulting in slow growth of all timothy cultivars of south- ern and northern origin. Björnsson and Helga- dottir (1988) estimated the temperature effects on annual dry matter yield of cool season grass- es at 644 kg/ha/°C. In previous studies timothy has usually had greater dry matter production at high than low latitudes (Deinum et al. 1981). The period for primary growth of timothy in Char- lottetownand Jokioinen is between mid-May and late June. During long daylight conditions, re- quirements for the photoperiodic stimulation of all the cultivars at the primary growth were likely met (Heide 1982, Ryle and Langer 1963) as the daylengths in the middle of May and June are 17.2 h and 19.1 h in Jokioinen, and 14.9 h and 15.7 h in Charlottetown, respectively. It appears that low precipitation and lower than normal temperature during this period reduced the growth of timothy in Jokioinen. Timothy cultivars of northern and southern origin had similar dry matter yields on average. Cultivars responded, however, differently at the 468 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^*73. Table 9. Mean acid detergent fibre (ADF) concentration (g/kg) of timothy cultivars in cuts 1 and 2 and differences in ADF between the years. Cultivar Cut 1 Cut 2 Charlottetown Jokioinen Charlottetown Jokioinen ADF Difference t ADF Difference ADF Difference ADF Difference Southern Climax 391 19 Drummond 396 Glenmor 400 31 12 38Itasca 395 26Richmond 383 Timfor 390 33 Toro 388 27 19Winmor 399 Northern Alma 377 30 Bottnia II 373 33 Korpa 382 26 Tiiti 387 27 271 1 276 17 0264 18265 260 12 263 5 252 17 268 1 281 12 267 23 273 10 268 17 301 23 300 12 315 10 329 13 333 7 335 24 339 20 317 22 287 7 288 14 285 II 284 10 291 4 302 19 303 12 302 17 297 -12 289 34 294 -1 315 -5 282 2 290 -29 258 -16 287 -1-1 Mean 388 27 267 11 309 15 292 2 sem, n=B, df = 138 3.46.4 3.46.4 5.811.3 5.811.3 N rate, kg/ha 100 392 28 269 11 290 2 290 0 150 384 26 266 11 295 27 295 4 sem, n = 48, df = 138 1.42.6 1.42.6 2.44.6 2.44.6 t Minus (-) denotes lower concentration in year 2 than year I. two sites with differences in dry matter yields of cut 1 being greater in Charlottetown than in Jokioinen.Niemeläinen and Rinne (1992) report- ed that in several experiments in southern Fin- land Tiiti, a northern cultivar, outyielded Climax, a southern cultivar, particularly in the first cut. In this study we did not observe such differenc- es. In Scotland (55.5° N) high-latitude timothy (origin 69° N) had lower yields in early spring and autumn than low-latitude (52°N) timothy while in late spring the reverse was true (Hay 1989). It is noted that the most stable cultivars, with the least difference in the dry matter yields between the two years, were Winmor in Char- lottetown and the four northern timothies in Jokioinen. Klebesadel and Helm (1986) noted similar differences in the adaptation of southern and northern timothies in Alaska. Nitrogen ap- plied at 90 kg/ha increased the dry matter yields over the 60 kg/ha rate concurring with previous findings (Kunelius et al. 1976, Lindgren and Lindberg 1988). Plant characteristics varied considerably be- tween Charlottetown and Jokioinen. The pani- cles were longer and applied N had greater ef- fect on panicle length under shorter days in Char- lottetown than in Jokioinen which is in agree- ment with Ryle and Langer (1963). Tiiti, Alma and Climax had longest panicles at both sites. The stem length was also greater in Charlotte- town than in Jokioinenbut nitrogen rate had lit- tle effect on stem length. Balasko and Smith 469 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Kunelius , H.T. el al. Yields, plant characteristics, total N andfibre composition oftimothy cultivars Table 10. Mean hemicellulose concentration (g/kg) of timothy cultivars in cuts 1 and 2 and differences in hemicellulose concentrations between the years. Cultivar Cut I Cut2 Charlottetown Jokioinen Charlottetown Jokioinen Hemi- Difference t Hemi- Difference Hemi- Difference Hemi- Difference cellulose cellulose cellulose cellulose Southern Climax 281 Il Drummond 298 Glenmor 285 21 16 Itasca 291 19 Richmond 285 4 Timfor 290 1 Toro 283 8 2Winmor 285 Northern Alma 289 I Bottnia II 286 20 Korpa 297 13 329 20 351 44 330 -6 326 23 325 13 330 6 317 5 329 3 337 41 346 48 335 32 2 2 280 288 14283 275 II 1276 279 8 4 5 272 283 273 4 275 I 276 5 316 -19 304 -28 296 -41 307 -34 297 -30 299 -22 307 -18 295 -31 330 0 329 -18 332 -2-2 Tiili 290 15 348 36 276 -5 326 17 Mean 288 II 334 22 278 3 311 -19 sem, n=B, df = 138 3.16.5 3.16.5 3.16.7 3.16.7 N rate, kg/ha 100 292 12 333 20 278 -2 310 -22 150 285 10 333 24 278 9 312 -15 sem, n = 48, df = 138 1.32.7 1.32.7 1.32.7 1.32.7 t Minus (-) denotes lower concentration in year 2 than year 1. (1971) found that N fertilization increased both panicle length and stem length of timothy. Among cultivars Itasca and Bottnia II had least difference in stem length in the two years. In this study the leaf content of timothies was similar in the two sites but leafiness among cul- tivars varied less in Jokioinen than in Charlotte- town. These results concur partially with the findings by Heide et al. (1985) who showed that long-day stimulation, in comparison with very short (8 h) day conditions, increased the plant height and leafarea of high latitude timothy (or- igin 69°N). Nitrogen fertilization has been shown to increase the leafarea oftimothy (Balasko and Smith 1971) but in this study the nitrogen rates had no effect on leaf content. It is noted that differences in plant maturity were neglible in Jokioinen while maturity dif- ferences were up to 10 days in Charlottetown. There is limited information on the maturity of timothy cultivars grown at different latitudes but field observations indicate small differences in maturity of timothy cultivars at northern latitudes (>6O°N). Phytotron studies of Hay and Peder- sen (1986) suggest that under long-day condi- tions timothy cultivars of varying latitudinal or- igin responded to photoperiodic stimulation of dry matter production in a similar way. There were, however, differences in stem apex devel- opment as low latitudecultivars S4B amd Motim had more uniform reproductive development than high latitude cultivar Engmo. In Alaska 470 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^73. (61.5°) Klebesadel (1970) found that anthesis progressed earliest on northernmost-adapted strains of timothy and bromegrass (Bromus in- ermis Leyss.), and followed on successively lat- er dates with progressively more southerly adapt- ed strains. In Jokioinen the day length is about 19 hours in June during the period for primary growth and there were no marked differences in maturity of the timothy cultivars included in this study. The fibre concentrations oftimothy cultivars varied between the two sites. The NDF concen- trations of timothy cultivars in cut I were, on average, 76 g/kg lower in Jokioinen than in Char- lottetown. Similarly, mean ADF concentration was 121 g/kg lower in Jokioinen than Charlotte- town. These effects are large enough to have in- fluence on the performance of animals consum- ing such forages. Previous work on forage spe- cies grown at different latitudes has demonstrat- ed differences in the compositon of timothy. Deinum et al. (1981) found that digestibility of organic matter oftimothy declined faster at high- er latitudes but, at similar morphological matu- rities, digestibility of the whole crop was great- er at high than low latitude sites. This study indicates that dry matter yields, plant characteristics and fibre composition were site dependent for the cultivars. Both southern and northern cultivars grew well in Charlotte- town particularly in primary growth but there were large differences in yield stability among cultivars. In Jokioinen locally developed north- ern cultivars outyielded southern cultivars in primary growth. The significance of observed differences in NDF and ADF in relation to the performance of ruminants (Mason and Flipot 1988) and horses (Maeta et al. 1992) require fur- ther study. Acknowledgements. We are indebted to Dr. K.B.Mcßae, S.A.E. Fillmore and Dr. L.Halliday for statistical analyses and interpretation of data, and J.Rowell, D.G.Lea and W.S.Moase for technical assistance. Research in Charlot- tetown was funded by Canada-Prince Edward Island Co- Operative Agreement. References Association of Official Analytical Chemists. 1989. Protein in animal feed, combustion method. Journal of Association of Official Analytical Chemists 72: 770, Balasko, J.A. & Smith, D. 1971. Influence of tempera- ture and nitrogen fertilization on the growth and compo- sition of switchgrass (Panicum virgatum L) and timothy (Phleum pralense L) Agronomy Journal 63: 853-857. Bélanger, G., Richards, J.E. & Walton, R.B. 1989. Ef- fects of 25 years of N, P and K fertilization on yield, per- sistence and nutritive value of a timothy sward. Canadi- an Journal of Plant Science 69: 501-512. Björnsson, H. & Helgadöttir, A. 1988. The effects of climatic variations on agriculture In Iceland: The effects on grass yield and their implications for dairy farming. In: Parry, M.L. et al. (eds.). The impact of climatic variations on agriculture. Vol. I Assessments in cool temperature and cold regions. Kluwer Academic Publishers, Dord- recht, The Netherlands, p. 445-474. Deinum, 8., deßeyer, J., Nordfeldt, P.H., Kornher. A., Ostgård, O. & vanßogaert, G. 1981. Quality of herbage at different latitudes. Netherlands Journal of Agricultural Science 29: 141-150. Genstat 5 Committee 1993. Genstat 5 release 3 refer- ence manual. Oxford University Press, Oxford, UK. 796 p. Hay, R.K.M. 1989. The performanceof high-latitude grass varieties under Scottish conditions: seasonal distribution of dry matter production. Grass and Forage Science 1989. p, 405-410. - & Pedersen, K. 1986. Influence of long photoperiods on the growth of timothy (Phleum pratense L.) varieties from different latitudes in northern Europe. Grass and Forage Science 41: 311-317. Heide, O.M. 1982. Effects of photoperiod and tempera- ture on growth and flowering in Norwegian and British timothy cultivars (Phleum pratense L). Acta Agricultures Scandinavica 32: 241-252. -, Hay, R.K.M. & Baugeröd, H. 1985. Specific daylength effects on leaf growth and dry matter production in high- latitude grasses. Annals of Botany 55: 579-586. Hunt, 1.V., Frame, J. & Harkess, R.D. 1979. The effect of date of primary growth harvest and levels of nitrogen and potassium fertilizers on the dry matter production of timothy (Phleum pratense L). Grass and Forage Science 34: 131-137. Klebesadel, L.J. 1970. Influence of planting date and 471 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Kunelius, H.T el al. Yields, plant characteristics, totalN andfibre composition of timothy cultivars latitudinal provenance on winter survival, heading, and seed production of bromegrass and timothy in the subar- ctic. Crop Science 10: 594-598. - & Helm, D. 1986. Food reserve storage, low-tempera- ture injury, winter survival, and forage yields of timothy in subarctic Alaska as related to latitude-ot-origin. Crop Science 26: 325-334. Kline, P. & Broersma, K. 1983, The yield, nitrogen and nitrate content of reed canarygrass, meadow foxtail and timothy fertilized with nitrogen. Canadian Journal of Plant Science 63: 943-950. Koch, D.W. 1976. In vitro dry matter digestibility in timo- thy (Phteum pratense L.) cultivars of different maturity. Crop Science 16: 625-626. Kunelius, H.T., MacLeod, J.A. & Macßae, K.B. 1987. Effect of urea and ammonium nitrate on yields and nitro- gen concentration of timothy and bromegrass and loss of ammonia from urea surface applications. Canadian Journal of Plant Science 67: 185-192, - & Mcßae, K.B. 1987. Effect of defoliating timothy cul- tivars during primary growth on yield, quality and per- sistence. Canadian Journal of Plant Science 66: 117- 123. - , Suzuki, M. & Winter, K.A.1976. Influence of harvest systems and nitrogen rates on yields, quality and per- sistence of Champ timothy in the seeding and postseed- ing years. Canadian Journal of Plant Science 56: 715- 723. Lindgren, E. & Lindberg, J.E. 1988. Influence of cut- ting time and N fertilization on the nutritive value of timo- thy. I.Crude protein content, metabolizable energy and energyvalue determined in vivo vs in vitro. Swedish Jour- nal of Agricultural Research 18: 77-83. Maeta, Y., Yoshida, S., Kamide, A. & Ishiguri.T. 1992 Effect of cutting time on digestibility, intake and nutritive value of timothy (Phteum pretense) hay in horses. Japa- nese Journal of Equine Science 3: 137-142. Mason, W.N. & Flipot, P.M. 1988. Evaluation of timothy cultivars for voluntary intake and nutrient components.Canadian Journal of Plant Science 68:1121 - 1129. Mfka, V. 1983. A comparison of nutritive values of early and late varieties of timothy. Grass and Forage Science 38: 67-71. Moore, K.J., Moser, L.E., Vogel, K.P., Waller, S.S., Johnson, B.E. & Pederson, J.F. 1991. Describing and quantifying growth stages of perennial grasses. Agrono- my Journal 83: 1073-1077. Niemeläinen, O. & Rinne, K. 1992, Performance of tim- othy cultivars in Finland. Proceedings of 14th General Meeting of European Grassland Federation, Lahti, Fin- land. p. 451-452. Pulli, S. 1980. Development and productivity of timothy (Phteum pratense L.). Journal of the Scientific Agricul- tural Society of Finland 52: 368-392. Ryle, G.J.A. & Langer, R.H.M. 1963. Studies on the physiology of flowering of timothy (Phteum pratense L.) I. Influence of daylength and temperature on size of in- florescence. Annals of Botany 27: 213-231. Schjelderup, 1., Aastveit, A.H. & Aastveit, K. 1994. Winter hardiness in marginal populations of timothy. Eu- phytica 77: 193-198. Surprenant, J., Drapeau, R. & Fernet, C. 1993. Culti- var-by-management interaction effects on timothy yield and quality evaluation. Canadian Journal of Plant Sci- ence 73: 445-460. Van Soest, P.J. 1982. Nutritional eclogy of the ruminant. O&B Books Inc..Corvallis, Oregon. 374 p. 472 AGRICULTURAL AND FOOD SCIENCE IN FINLAND Vol. 5 (1996): 461^)73. SELOSTUS Timoteilajikkeiden sadot, kasvuominaisuudet sekä typpi- ja kuitupitoisuus kahdella leveysasteella H. Tapani Kunelius, Pertti Pärssinen ja Seppo K. Pulli Agriculture and Agri-Food Canada, Boreal Suomen Kasvinjalostus ja Maatalouden tutkimuskeskus Pohjoista (> 60°N) ja eteläistä (46°N) alkuperää ole- via timotei (Phleum pratense L.) lajikkeita tutkittiin Jokioisissa ja Prinssi Edwardin Saarella Kanadassa. Timotei niitettiin kahdesti kasvukauden aikana typ- pilannoituksen ollessa 100 tai 150 kg/ha. Kuiva-ainesadot olivat suuremmat Kanadassa ja pohjoiset lajikkeet olivat satoisampia. Typpilannoi- tus lisäsi satoa I 400 kg/ha. Timotein korret ja täh- kät olivat pitempiä Kanadassa, ja molemmissa tutki- muskohteissa pohjoisten lajikkeiden tähkät olivat pi- tempiä. Lehtipitoisuus vaihteli 139 g/kg ja 230 g/kg välillä. Pohjoiset lajikkeet olivat typpipitoisempia (22,1 g/kg) kuin eteläiset lajikkeet (19,7 g/kg). En- simmäisessä niitossa NDF- ja ADF-pitoisuudet oli- vat alhaisempia Jokioisissa, missä myös eteläisten lajikkeiden NDF oli alhaisempi. Suurimmat lajikkei- den väliset erot ADF-pitoisuudessa olivat 29 g/kg ensimmäisessä niitossa ja 57 g/kg toisessa niitossa. Tämä tutkimus osoittaa, että pohjoista alkuperää olevat timoteilajikkeet olivat satoisia myös huomat- tavasti eteläisemmällä leveysasteella. Pohjoismaiden kasvinjalostajilla voisi siten olla mahdollisuuksia ke- hittää nurmiheinälajikkeita esimerkiksi Pohjois-Ame- rikan alueille, missä ilmastolliset olosuhteet ovat sa- manlaisia. 473 AGRICULTURAL AND FOOD SCIENCE IN FINLAND