Italian Ryegrass Varieties Research Articles

내한 조숙성 이탈리안 라이그라스 신품종 '코스피드'

This experiment was carried out to breed the cold-tolerant variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 1999 to 2005. New variety, `Kospeed` is a diploid variety with green in leaf color, and has semi-erect and erect growth habit in late autumn and early spring, respectively. `Kospeed` was on 1 May in heading date as a early-maturing variety. Also `Kospeed` was wider by 0.2mm in flag leaf width, longer by 1cm in flag leaf length and shorter by 1cm in plant length than those of `Florida 80`, respectively. Stem width of `Kospeed` was similar to that of `Florida 80` and `Hwasan 101`. Cold tolerance of `Kospeed` was better than that of `Florida 80`. Dry matter (DM) yield (13,257kg/ha) of `Kospeed` was similar to that of `Florida 80`. In vitro dry matter digestibility (IVDMD) and total digestible nutrient (TDN) of `Kospeed` were 73.2% and 65.3% which are 2.1% and 1.7% higher than those of `Florida 80`, respectively. Acid detergent fiber(ADF) and neutral detergent fiber (NDF) of `Kospeed` were 29.1% and 53.1% which are 2.1% and 2.3% lower than those of `Florida 80`, respectively.

내한 다수성 이탈리안 라이그라스 신품종 '코위너'

본 연구는 이탈리안 라이그라스 내한성 품종 을 육성하기 위하여 1987년부터 2005년까지 농촌진흥청 축산연구소 조사료자원과에서 수행되었다. 신품종 '코위너'는 4배체 품종으로서 엽의 색은 농녹, 월동전 초형은 반포복형, 봄의 초형은 중간형이었다. '코위너'는 5월 19일경에 출수하는 중만생 품종으로 지엽의 길이가 29cm 로서 '화산 101호'와 같았으며 최장간장은 70cm로 '화산 101호' 보다 3cm 길었으며, 초장 은 97cm로 '화산 101호' 보다 3cm 길었다. 또한 '코위너'는 줄기 두께가 '화산 101호' 보다 두터웠으며, 1차 수확 후 재생이 양호하였다. '코위너' 품종의 내한성은 '화산 101호' 보다 다소 약하고 'Florida 80' 보다는 다소 강하였다. '코위너'의 건물수량은 14,345kg/ha로서 '화산 101호' 보다 8% 많았다. '코위너'의 사료가치는 in vitro 건물소화율(IVDMD)이 76.2%, 가소화양분총량(TDN)이 63.3%로서 '화산 101호' 보다 각각 1.6, 0.4% 낮았다. This experiment was carried out to breed the cold-tolerant variety of Italian ryegrass(Lolium multiflorum Lam.) in Grassland and Forages Division, National Livestock Research Institute, RDA, Suwon from 1987 to 2005. New variety, Kowinner as a tetraploid variety was dark green in leaf color and growth habit in autumn and early spring was semi-prostrate and medium, respectively Kowinner as a medium or late-heading variety was 19th May in heading date. Flag leaf length of Kowinner was 29 cm that was the same as control variety, Hwasan 101. Length of longest stem and plant length of Kowinner were 70 cm and 97 cm that was longer 3 cm than those of Hwasan 101, respectively. Stem width of Kowinner was thicker than that of Hwasan 101. Expecially, Kowinner was very good in regrowth. Cold tolerance of Kowinner was slightly weaker than that of Hwasan 101 and slightly stronger than that of Florida 80. Dry matter(DM) yield(12,884 kg/ha) of Kowinner was 8% more than that of Hwasan 101. In vitro dry matter digestibility and total digestible nutrient(TDN) of Kowinner were 76.2 and 63.3% that was 1.6 and 0.4% lower than those of Hwasan 101, respectively.

Pumpkin Yield and Weed Populations Following Annual Ryegrass

ABSTRACT Sustainable production can sometimes be achieved with diversification of cropping patterns and by the use of disparate crops in rotation. Following a forage grass harvest for feed it may be possible to produce a cucurbit crop before it is time to reseed an overwintering grass cover crop. Pumpkins may be a crop that can be grown in rotation with grasses. Five annual Italian ryegrass varieties of varying maturity [“Shiwasuaoba” (early); “Miniamioba” and “Waseyutaka” (medium); “Marshall” and “Zorro” (late)] were established in the fall. In early summer of the following year the grasses were harvested, their yield determined, and the stubble left in place. The control was composed of winter wheat which was harvested in the spring and the stubble turned under and the soil maintained without cover. Seed of pumpkin, cv. ProGold 300, were sown into strips tilled in the ryegrass stubble or bare soil. Number and weight of pumpkins were determined. Weed cover in plots following pumpkin harvest was determined. Plots were seeded with the ryegrasses or wheat, with the procedures repeated over two years. Marketable number and yield of pumpkin were not affected by cover or year of planting and averaged 1,755 fruit/ha and 5.9 Mg·ha−1, respectively, over both years. The percent of pumpkin fruit of the expected size for this cultivar, >7.25 kg, was 41% in the first year and 26% in the second year. Approximately 68% of fruit from plants on bare soil, and 27% from plants on soil covered with ryegrass stubble, were >7.25 kg. Total weed cover was not different on bare soil between years (avg. 86%), and dicot weeds were greater in 2002 than 2003. Total weed cover in ryegrass plots averaged about 36% in 2002 and 93% in 2003. Dicot weed cover in ryegrass stubble plots were not different between years or ryegrass variety and averaged 32%. Monocot weed cover was significantly lower in 2002, 5%, than in 2003, 57%, regardless of cover. There is a need for additional studies in ryegrass-pumpkin rotation before recommendations can be made for its implementation in southeastern Oklahoma.

내한 조숙성 이탈리안 라이그라스 신품종 '코그린'

본 시험은 이탈리안 라이그라스 내한성 품종을 육성하기 위하여 1999년부터 2005년까지 축산연구소 조사료자원과에서 수행되었다. 이탈리안 라이그라스 신품종 '코그린'은 2배체 품종으로서 엽의 색은 녹이며, 월동전 초형은 반직립형, 봄의 초형은 직립형이다. 코그린은 5월 4일경에 출수하는 조숙성 품종이었다. 특히, '코그린'은 'Florida 80' 보다 지엽의 폭이 0.7mm, 지엽의 길이가 2cm로 넓고 길며, 초장은 85m로 Florida 80 보다 1cm 정도 작았다. 줄기의 두께는 'Florida 80'과 같이 중간이었다. '코그린'의 내한성은 'Florida 80' 보다 강한 품종이었다. '코그린'의 건물수량은 12.884kg/ha로서 'Florida 80' 보다 3% 적었다. '코그린'의 사료가치는 in vitro 소화율이 74.7%, 가소화영양분총량(TDN) of 65.1%로서 'Florida 80' 보다 각각 3.6, 1.5% 높았고, 산성세제불용섬유(ADF)와 중성세제불용섬유(NDF)는 30.1 및 54.1%로서 'Florida 80' 보다 각각 1.9 및 1.3% 낮았다. This experiment was carried out to breed the cold-tolerant variety of Italian ryegrass (Lolium multiflorum Lam.) at the Grassland and Forage Crops Division, National Livestock Research Institute, RDA at Suwon, Korea, from 1999 to 2005. The new variety 'Kogreen' is a diploid variety with a green leaf color and had semi-erect habit in late autumn and erect growth habit in early spring. The heading date of 'Kogreen' was on May 4, and for 'Florida 80' was May 2, both are considered as early-heading variety. 'Kogreen' was wider by 0.7mm in flag leaf width, longer by 2 cm in flag leaf length and shorter by 1cm in plant length than the control variety, Florida 80. Stem width of 'Kogreen' was similar to that of 'Florida 80' and 'Hwasan 101'. cold tolerance of 'Kogreen' was better than that of 'Florida 80'. Dry matter(DM) yield (12,884kg/ha) of 'Kogreen' was 3% less than that of 'Florida 80'. in vitro dry matter digestibility was 74.7% and total digestible nutrient was 65.1%, which are 3.6% and 1.5% higher than those of 'Florida 80', respectively. Acid detergent fiber and neutral detergent fiber of 'Kogreen' were 30.1% and 54.1% which are 1.9% and 1.3% lower than those of 'Florida 80', respectively.

이탈리안 라이그라스 신품종 '화산 104호'의 생육특성과 수량성

본 시험은 이탈리안 라이그라스 내한성 품종을 육성하기 위하여 1997년부터 2002년까지 축산기술연구소 초지사료과에서 수행되었으며, 이탈리안 라이그라스 신품종 "화산 104호"는 2002년 직무육성신품종선정심의회에서 명명되었다. "화산 104호"는 4배체 품종으로서 엽의 색은 농녹이며, 월동전 초형은 반부복형, 봄의 초형은 중간형이다. 특히, "화산 104호"는 "화산 101호" 보다 지엽의 폭과 길이가 넓고 길며, 초장이 105cm로 화산 101호 보다 7cm 정도 길고, 줄기의 두께는 화산 101호에 비하여 두꺼운 특성을 갖고 있다. 화산 104호의 내한성은 기존 내한성 품종인 화산 101호 보다 다소 강한 품종이었다. 화산 104호의 건물수량은 9,857 kg/ha로서 화산 101호 보다 <TEX>$5\%$</TEX> 많았다. "화산 104호"의 사료가치는 in vitro 소화율이 <TEX>$74.3\%$</TEX>,가 소화양분 총량 (TDN)이 <TEX>$63.1\%$</TEX>로서 화산 101호보다 <TEX>$1.5\%$</TEX> 낮고, 산성세제불용섬유(ADF)와 중성세제불용섬유(NDF)는 32.6 및 <TEX>$55.8\%$</TEX>로서 "화산 101호"보다 각각 1.9 및 <TEX>$2.4\%$</TEX> 높았다. This experiment was carried out to breed the cold-tolerant variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon from 1997 to 2002. Hwasan 104 as a tetraploid variety was dark green in leaf color and had semi-prostrate and medium growth habit in late autumn and early spring, respectively. Hwasan 104 was 19th May in heading date as a late-heading variety. Especially, Hwasan 104 was broader in flag leaf and longer 7 cm in plant length, and thicker in stem width than those of control variety, Hwasan 101. Cold tolerance of Hwasan 104 was better than that of Hwasan 101 registered as a cold-tolerant variety. Dry matter (DM) yield of Hwasan 104 was <TEX>$5\%$</TEX> more than DM 9,348 kg/ha of Hwasan 101. In vitro dry matter digestibility and total digestible nutrient of Hwasan 104 were 74.3 and <TEX>$63.1\%$</TEX> which are 3.3 and <TEX>$1.5\%$</TEX> lower than those of Hwasan 101, respectively. Acid detergent fiber and neutral detergent fiber of Hwasan 104 were 32.6 and <TEX>$55.8\%$</TEX> which are 1.9 and <TEX>$2.4\%$</TEX> higher than those of Hwasan 101, respectively.

이탈리안 라이그라스와 종.속간 잡종 및 생태형 유래 합성종간의 생육특성, 수량성 및 사료가치 비교

축산기술연구소 사료작물 육종연구실에서는 1984년부터 이탈리안 라이그라스의 기호성과 페스큐류의 높은 환경적응성을 결합하기 위해 Lolium X Festuca 잡종을 생산하였고, 1991년부터 이탈리안 라이그라스 생태형을 수집하여 특성을 검정하고 계통화하여 왔다. 1997년부터 이들 교잡계통과 생태형 중에서 임성이 있고 내한성이 강하며 출수기가 비슷한 영양계통으로 교배조합을 작성하여 Polycross 삼각배치법으로 합성종 내한 6, 7, 8, 9호를 육성하였다. 이들 합성종들의 형태적 및 농업적 특성 그리고 수량성과 사료가치를 비교하기 위하여 1999 년부터 2000년까지 경기 수원과 연천에서 이탈리안 라이그라스 Barmultra와 화산 101호 등의 기존품종들과 함께 공시하여 포장시험을 실시 하였다. 합성종들의 생육특성에서 출수기는 수원에서 5월 22~24일로 Barmulra나 화산 101호와 비슷한 만생종에 속하였다. 초장은 101~106cm, 줄기의 굵기는 중간 또는 굵었으며, 엽색은 농녹으로서 넓고 길며 풍엽성이 좋았다. 도복은 대체로 강한 편이었으며 재생은 양호하였다. 합성계통들의 내한성은 수원지역에서는 기존 의 이탈리안 라이그라스 품종들과 차이가 거의 없었으나, 1월 또는 2월 최저평균기온이 -l0~12% 였던 경기 연천지역에서는 기존 품종들 보다 내한성이 강하였다. 합성계통들의 건물수량은 수원지역에서는 Barmultra(8,236kg/ha)와 비슷하거나 다소 적었으나 연천지역에서는 Barmultra(7,291kg/ha) 보다 7~13% 많았다. 합성계통들의 사료가치는 in vitro 소화율, ADF, NDF, TDN 함량에 있어서 화산 101호보다는 다소 낮았으나 Barmultra보다는 다소 양호하였다. 큰 변화를 보이지 않았다. 이상의 결과에서 인공수정 및 복제수정란의 이식시 hCG 1,5001u를 투여한 한우 미경산우는 임신유지를 위한 혈중 P4의 농도를 상승시키며 수태율도 향상시키는 것으로 나타났다. IGF와 cortisol은 hCG 투여가 초기 임신기에는 큰 영향을 미치지 않는 것으로 나타났다.라 조금씩의 차이는 있었으나 소비자들이 주로 딸기향, 바나나향, 사과향, 초코향을 선호한다고 답하였다.p<0.05). 본 연구의 결과를 미루어 볼 때 앞으로 더 많은 연구가 되어져야 할 것이지만 채식은 연령 증가에 따른 심혈관질환 위험인자의 수준을 낮추는데 효과가 있을 것으로 사료된다. 대인관계 4개의 측정항목에서 높은 증가율을 보여 치료효과가 큰 것으로 판단된다. 원예 치료 실시 후의 자체설문지 평가결과 원예 활동을 통해서 달라진 점은 개인적으로 가족, 이웃 간의 긍정적인 변화를 이끌어내고 있다는 것을 발견할 수 있었고 다양한 원예프로그램이 인상깊었다고 하였으며 다음진행에 추가적으로 야외에서 진행할 프로그램에 대한 욕구가 표출되었다. 이것을 통해 개인적 치료경험과 가족, 이웃 간의 지지망 형성이 중요하며 긍정적인 영향을 주었다는 것을 볼 수 있었다. 또한 다양한 원예치료프로그램의 적용과 야외 활동을 조화롭게 적용한다면 성공적인 프로그램 진행에 도움을 될 것으로 판단된다. 이상의 결과를 종합하면 정신지체장애인에게 원예치료 프로그램을 실시한 이후에 원예에 대한 관심이 높고 자아존중 감이 향상되었으며 원예치료 프로그램에 대한 높은 만족도를 보였고 원예치료에 대한 참가성, 흥미성, 지속성, 대인관계성에서 높은 증가율을 보여 치료프로그램의 개입이 유의미한 효과가 있는 것으로 나타났다. 이러한 결과들 볼 때 의도적인 원예치료활동을 통해서 Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum <TEX>$\times$</TEX> L. pratensis and intergeneric hybrids of Lolium <TEX>$\times$</TEX> Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12<TEX>$^{\circ}C$</TEX> of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

First in vivo assessment of feeding value of Festulolium hybrids derived from Festuca arundinacea var. glaucescens and selection for palatability

AbstractThis paper reports on the first results of feeding value experiments, assessed with sheep, of hybrids between tetraploid Italian ryegrass (Lolium multiflorum, 2n = 4×= 28) and a progenitor of tall fescue, Festuca arundinacea var. glaucescens (2n = 4×= 28). Three hybrid populations resulting from either high, low or no selection for palatability were compared with a variety of Italian ryegrass as control and two varieties of the cultivated hexaploid (2n = 6×= 42) tall fescue, one of which had been selected for high palatability. On average, the hybrid populations were found to be as palatable as the improved tall fescue with voluntary intake (VI), in vivo digestibility of organic matter (DOM), and net energy expressed in fodder units for milk, similar to the best palatable tall fescue and to Italian ryegrass. However, selection for improved palatability among hybrids did not result in any further improvement of other traits, except VI in the hybrid selected for high palatability which significantly exceeded VI of Italian ryegrass. In conclusion, intergeneric hybridization between L. multiflorum and F. arundinacea var. glaucescens led to an immediate increase of feeding value compared with selection for palatability in tall fescue. However, to improve feeding value of hybrids further, similar selection for high palatability appeared questionable and possibly detrimental for other agronomic traits because of complicated inheritance in tetraploid L. multiflorum×F. glaucescens hybrids.

Comparison of two varieties of Italian ryegrass (Lolium multiflorum) for milk production, when fed as silage and when grazed

SUMMARYTwo varieties of Italian ryegrass (Lolium multiflorum Lam.), Tribune and RvP, were cut in each of 2 years, ensiled and individually fed, ad libitum, to dairy cows. In one year, two rates of supplementary concentrate feeding were compared and, in the other year, two types of concentrate and a silage-only diet. Tribune silage was more digestible, in vitro, and was lower in neutral detergent fibre and fibrosity index than RvP silage. There was no difference between the varieties, however, in the cows’ intake of silage. On the silage-only diet, the cows fed Tribune produced a higher yield of milk solids than did those fed RvP; on the other diets, there was no significant difference between varieties in the yield or composition of milk.The same two varieties were compared when grazed by herds of dairy cows in spring, summer and autumn of the first harvest year on six farms and in the second harvest year on four of the farms. Tribune persisted much better than RvP, in numbers of plants and tillers/m2 and in ground cover, and the herbage was more digestible than that of RvP. Milk yield/cow was c. 0·6 kg per day higher when grazing Tribune than when grazing RvP.

VARIETIES OF ITALIAN RYEGRASS IN NEW ZEALAND

To assist farmers and their advisers in becoming familiar with the many different varieties of Italian ryegrass currently available, this paper compares morphological, physiological and biochemical characteristics of Concord, Ceres Progrow, Lemtal (Belgium), Grasslands Tama, Grasslands Paroa, Grasslands Moata, Te Puna, Te Rahu, Bradley, Rakaia and also Grasslands Manawa, a hybrid cultivar which behaves as a persistent Italian ryegrass. In trials at Palmerston North in 1966/67, Moata stood out for its size in comparison to all other lines. Rakaia and Progrow from the South Island were short-lived and early heading, went directly to head after spring sowing and had large heads and many florets per spikelet, despite small size of leaves and plants. By contrast, Concord and Te Rahu from North Island dairy pastures were persistent, later heading and large in both vegetative and reproductive characteristics. All the varieties based on NZ material were quicker to germinate than any of the cultivars bred from overseas material, and, except Bradley, contained Acremonium endophyte. Keywords: Lolium multiflorum Lam., crown rust, germination, vernalisation, electrophoresis, seed protem banding, vegetative and reproductive characteristics, Acremonium endophyte.

Winter hardiness in Lolium multiflorum Lam. III. Selection for improved cold tolerance and its effect on agronomic performance

AbstractNine varieties of Italian ryegrass were subjected to two generations of selection for cold tolerance using a controlled environment test. Selection led to a significant overall improvement in average tiller survival from 39·8 to 47·7%, even though the selection intensity achieved was not more than 20%. Although individual varieties varied in initial tolerance from 31·1 to 71·4%, the cold room tests were not sufficiently sensitive to attach significance to differences in response to selection which varied from 0·3 to 17·6%. Agronomic assessment of spaced plants indicated that the winter and spring growth potential of all nine varieties was unaffected by selection for cold tolerance. Although some of the selected populations showed a significant decline in their total yields and persistency, others showed no significant change in these characteristics. The plant breeding implications of these results are discussed.

Winter hardiness in Lolium multiflorum Lam. II. The effect of defoliation and nitrogen application as assessed by low temperature response in a controlled environment

AbstractThe effect of defoliation and nitrogen application on the cold tolerance of four varieties of Italian ryegrass was assessed using controlled environment chambers. Both defoliation and nitrogen fertilizer markedly reduced overall cold tolerance and this closely matched changes in winter hardiness induced by similar treatments applied to the same varieties in a field experiment. However, the relative response of individual varieties differed from that found under field conditions. Thus, RvP showed high levels of tolerance to low temperatures in the controlled environments and was also winter‐hardy under field tests; by contrast Bb 1430, although previously shown to be winter hardy in the field, exhibited low tolerance of cold stress in growth chambers. Thus, results obtained in controlled environment tests cannot be entirely equated to winter hardiness in the field.Water‐soluble carbohydrate (WSC) levels were reduced by both defoliation and nitrogen application and there were significant overall differences between varieties. It was not possible, however, to detect any clear relationship between these differences in WSC levels and cold tolerance.The significance of these results in relation to the use of controlled environment chambers for selecting for improved winter hardiness is discussed.

Winter hardiness in Lolium multiflorum Lam. I. The effect of nitrogen fertilizer and autumn cutting managements in the field

AbstractFour Italian ryegrass varieties of different origins and winter hardiness were grown as spaced plants at a lowland and an upland site and subjected to ten managements comprising two nitrogen levels and five autumn cutting treatments. Tiller mortality after the winter of 1971–72 was measured in March and subsequent spring recovery from winter damage in April.Although the winter was not severe, there was considerable winter kill, particularly at the upland site where the most severe treatment combinations killed up to 90% of the plants of the more susceptible varieties. In general, winter kill was increased by raising the level of nitrogen fertilizer and by late or frequent autumn defoliations, and significant interactions between locations and the two treatment factors emphasized the importance of the siting of the experiment.The varieties difFered in their overall winter hardiness, with Bb 1430 and RvP suffering less tiller mortality than S22 and Grasslands Paroa in all the treatment combinations, but significant interactions of varieties with locations and cutting treatments revealed that the magnitude of the difference between varieties varied with location and cutting management. Regression analysis of these interactions, however, showed that the tiller mortality of all four varieties increased linearly with the increasing stresses applied by the location × management combinations. There was no differential variety recovery from winter kill, the spring yields being entirely related to the level of tiller mortality experienced.These results are discussed in relation to the breeding of winter hardy varieties, the choice of variety and autumn management practice.

Some varietal differences in factors affecting nutritive value and in recovery after cutting in Lolium multiflorum

SummaryFour varieties of Italian ryegrass (Lolium multiflorum), which have been found to differ in voluntary intake by livestock at the same level of digestibility, were examined in the year of sowing and in the two subsequent years in a field experiment. Eight dates of first harvest during May–June in the years after the year of sowing were compared. During May–June in these years the proportion of leaf in the crop was closely related to the stage of development of the crop relative to heading date, whereas yield and digestibility were more closely related to calendar date. As a result the later-heading varieties, S. 22 and Sabalan, had a higher proportion of leaf than the earlier-heading varieties, RvP and Tetila Tetrone, at a given yield and digestibility and this may at least partly account for higher intake in the former varieties. In addition, in Sabalan, the proportion of green leaf relative to dead was particularly high and the proportion of cell wall particularly low. The surface area per unit dry weight of leaf blade was much higher than that of ‘stem’, which may contribute to shorter retention time in the reticulo-rumen. Surface area per unit weight of both leaf blade and ‘stem’ declined with delay in date of first harvest.The yield of RvP relative to the other varieties was modest at the first harvest in the years after the year of sowing and high at subsequent harvests, in accord with National Institute of Agricultural Botany results. The high yield of RvP relative to the other varieties after the first harvest appeared to be associated with a relatively large number of tillers with their shoot apex below cutting height at the time of first harvest. It seemed that most of these tillers had emerged during the few weeks before that harvest. The proportion of tillers with their shoot apex below rather than above cutting height at the time of first harvest was higher in all four varieties than casual observation would suggest and the proportion remained rather high throughout May and June. The rapid rate of turnover of tillers in Italian ryegrass was confirmed.

The effect of thermal and mechanical treatment on the drying rates of leaves and flowering stem internodes of Italian ryegrass (Lolium multiflorum) measured in the laboratory

SUMMARYThe drying rate of leaves and stem internodes from flowering culms of two varieties of Italian ryegrass (Lolium multiflorum) were measured in the laboratory in controlled conditions of temperature (28 °C), relative humidity (22%) and air speed (40 cm/sec), without treatment, or after being subjected to thermal treatment or to mechanical damage followed by thermal treatment. The two treatments increased the drying rate of leaves and, to a greater extent, stem internodes.While it cannot be concluded that all treatments that increase crop drying rate will increase the rate for stems more than for leaves, these results are considered to indicate the possibility of devising practical treatments which will. Such treatments could reduce leaf shatter and consequent serious loss of dry matter during the field drying of grass crops.

The cellulose-lignin complex in forages and its relationship to forage nutritive value

SUMMARYThe relationships between the cellulose-lignin complex, voluntary consumption and dry-matter digestibility were examined using forages of two varieties of Italian ryegrass and two legumes, lucerne and sainfoin. These forages had previously been shown to exhibit different intake-digestibility relationships. The cellulose, acid detergent lignin and acid detergent fibre contents of these forages as well as their digestibility coefficients were determined. Lignins were extracted from the fibre fractions and their ultraviolet difference spectra determined.Changes in maturity of a forage during a single growth phase, produced changes in dry-matter digestibility which were closely associated with changes in the digestibility of the cellulose and inversely related to the lignin content of the forage. Differences in digestibility between varieties of forage were less closely associated with lignin content. As the grasses matured a lignin fraction forming a difference peak at 350 mμ became evident and this was associated with decreased cellulose digestibility.Differences in voluntary food consumption resulting from changes in maturity of a single forage variety, in one growth phase, were also closely correlated with both dry matter and cellulose digestibility and inversely with lignin content. Differences between varieties and growth phases of the ryegrasses and between grasses and legumes were related less to the nature of the cellulose-lignin complex and more closely to the percentage of the total digesta deriving from cellulose.Sainfoin was characterized by the formation post-ruminally of an artifact that analysed quantitatively as lignin and qualitatively resembled a non-conjugated phenolic lignin fraction. The production of this artifact apparently disturbed fibre digestibility estimates and may have affected dry-matter digestibility estimates. Degradation of lignin apparently occurred both in the rumen and in the hind gut.

水田輪換畑におけるイタリアンライグラスと野ビエの連続栽培に関する研究 : 第1報 刈取間隔・イタリアンライグラス品種および施肥量について

水田輪換畑におけるイタリアンライグラスと野ビエの連続栽培に関する研究 : 第1報 刈取間隔・イタリアンライグラス品種および施肥量について

A COMPARISON OF RYEGRASS VARIETIES FOR EARLY–BITE PRODUCTION

The value of varieties of Italian, hybrid and Westerwold ryegrass for early‐bite production was compared at 32 centres in different environments. The relative performance of Italian ryegrass varieties was fairly consistent from centre to centre over a period of 3 years. Danish and Leda Daehnfeldt Italians produced the most, and S22 the least, early spring production. Good early‐bite and total annual yields were obtained from hybrid ryegrasses. Swards sown in the previous autumn were more winter‐hardy than spring‐sown swards and appeared to be as early in the following year.

PRODUCTIVITY, PERSISTENCE AND RESPONSE TO NITROGEN OF ITALIAN RYEGRASS VARIETIES

The production of six varieties of Italian ryegrass was compared for three years by cutting 5 or 6 times during the growing season. All varieties showed falls in production of dry matter at high and low levels of N fertilization, but New Zealand HI and New Zealand Italian ryegrass showed significantly lower falls and gave top yields over the three years, in spite of severe frost damage in the first two. Crude protein and nitrogen absorption remained high at the lower level of fertilization (174–209 lb N/acre) and showed a fall only in the third year at the high level of N fertilization (348–418 lb N/acre).The significance of the high response of the New Zealand varieties is discussed.