THE POTENTIAL VALUE OF SILAGE EFFLUENT AS A FERTILIZER

Results of the analysis for dry-matter, nitrogen and major base content of 9 silage effluents obtained from farm silos and 3 effluents from experimental tower silos are presented. The mean values obtained for the principal plant nutrients in the 12 effluents examined were 0·19% N, 0·037% P and 0·38% K. The results indicate that effluents may be a useful source of plant nutrients, particularly when undiluted with rainwater, and that, in general, silage effluents appear to be superior to liquid manure in manurial value.     

SILAGE AND MILK PRODUCTION. A COMPARISON BETWEEN BARLEY AND DRIED GRASS AS SUPPLEMENTS TO SILAGE OF HIGH DIGESTIBILITY

Grass silage made in late May from S23 perennial ryegrass was offered to 14 Ayrshire cows in a 16–week winter-feeding experiment. The silage had a DM content of 23.2% and contained 16–8% CP and 70.4% digestible organic matter in the DM. The silage was fed ad lib. as the sole feed in the control treatment, and supplemented with either barley or higuality dried grass cubes at the rate of 2, 3 and 4 kg/10 kg milk (2, 3 and 4 Ib/gal) in the other 6 treatments. The daily intake of silage DM was 11.6 kg/cow (25.6 lb) in the control, and significantly less in the supplement treatments. Silage intakes were higher in the dried grass than in the barley treatments. The mean daily yields of milk were 14.5 kg.cow (32.0 lb) in the control, 15.7, 16.6 and 17.0 kg (34.6.36.6 and 37.5 lb) in the barley treatments, and 17.8, 20.2 and 19.8 kg (39.2, 44.5 and 43.6 lb) in the drierass treatments, at the 2, 3 and 4 kg rates of feeding, respectively. The solidoat (SNF) content of the milk was lowest in the control treatment and highest in the drierass treatments. It is concluded that grass silage of high digestibility could be made successfully on a farm scale and that, with such a silage, a supplement of higuality dried grass was superior to a supplement of barley for milk production.     

A COMBINATION OF NITRITE AND HEXAMINE AS AN ADDITIVE IN THE ENSILING OF HERBAGE

The development and testing of a new silage additive consisting of sodium nitrite and hexamine (hexamethylenetetramine) are described. The investigation was conducted over 8 years and consisted of 15 separate experiments with small steel cylinders and 13 with plastic sacks. The former were carried out with freshly cut blue lucerne and a storage temperature of 25°. When a mixture of sodium nitrite and hexamine was applied at the rate of 0.4% of fresh herbage weight, the quality of the resulting silage was superior to that made with commercial additives marketed in Sweden and the losses were considerably reduced.     

白浆土上大豆“三垄”栽培法的效应分析

本试验于１９８９－１９９１年在黑龙江省８５４农场进行,土壤类型为白浆土。本文探讨了低湿地白浆土上“三垄”栽培法和平作栽培法两种不同耕作方式对大豆生长及产量的影响,结果表明,大豆“三垄”栽培法与平作相比,三年平均增产１６．３１％。产量差异达τ０．０１显著水平。在“三垄”栽培条件下,大豆叶面积指数,光合势,叶／粒比和经济系数显著。与平作相比,“三垄”栽培法在大豆的生育前期使０－２０ｃｍ土层的温度和土壤     

A STUDY OF SEED DEVELOPMENT AND YIELD IN TIMOTHY AS RELATED TO DATE OF HARVEST

Studies of seed development and yield were conducted on three Aberystwyth varieties of timothy. The stages of seed development are described, as are their correlation with the external appearance of the head. Evidence is presented to support the suggestion that the latitude in the dale of harvest is greater than has hitherto been accepted. Population studies of seed crops have revealed that the abundant small heads (less than 4 cms. in length) contribute very little to the yield. The partition of the yield amongst the different inflorescence age-groups is given for each variety and methods of judging crop ripeness are discussed.     

A COMPARATIVE STUDY OF PAPER AND OIL AS CARRIERS OF CHROMIUM SESQUIOXIDE ADMINISTERED TO GRAZING STEERS TO DETERMINE THEIR FAECAL OUTPUT

Two steers excreting similar quantities of organic matter daily were grazed at pasture during the summer of 1961. The four experiments each involved a preliminary period of five days dosing with Cr₂O₃ to reach a fairly constant excretion. The steers received a daily dose of Cr₂O₃ either in oil suspension or in shredded paper. The carriers and steers were interchanged for each trial. For two of the trials each steer in turn was harnessed every other day and all its dung collected in a bag. Total faecal excretion of organic matter was measured from the bagged steer and estimated from the Cr₂O₃ concentration in a composite sample made up from all dung pats voided during the ten-day collection period. In the other two trials the steers were not harnessed and each dung pat was separately sampled and analysed for Cr₂O₃ in the organic matter. The average recovery of Cr₂O₃ in the first two trials was 99·1 (oil) or 94·4% (paper). Calculating the faecal organic matter excretion from the concentration of Cr₂O₃ in the faeces and the quantity given daily overestimated it by 3·5 to 8·0%. There was no significant difference between shredded paper and oil as carriers of Cr₂O₃ for estimating the quantity of organic matter excreted. There were 37% and 22% less variation between dung pats in Cr₂O₃ concentration when this was administered in shredded paper than when given in oil suspension.     

THE EFFECT OF RELATING APPLICATIONS OF NITROGEN TO THE STAGE OF DEVELOPMENT OF COCKSFOOT (DACTYLIS GLOMERATA L.) GROWN FOR PRODUCTION OF SEED

An experiment is described in which nitrogen was applied in relation to the physiological stage of development in cocksfoot grown for seed. All applications of N increased the yield of seed, but applying all the N during the phase of autumnal tillering was less effective than applying it at stages of development in spring (beginning of vernal growth, initiation of inflorescences, complete differentiation of inflorescences), or in autumn and spring, because of a decrease in the number of tillers which survived to flower in the following year. Differences due to the stage of development at which N was applied in spring were small. Primary effects of N were to increase the number of tillers and ears per plant, and to accelerate the rate of development of inflorescences; in addition, N advanced the date of initiation of inflorescences without similarly advancing the date of complete differentiation of inflorescences. It is concluded that a long period between the initiation and complete differentiation of the inflorescence is conducive to high yields of seed.     

DEFOLIATION AND MANURING OF PERENNIAL RYEGRASS (S24) FOR SEED PRODUCTION

Autumn defoliation of the early perennial ryegrass, S24, expedited or delayed heading and increased or decreased the number of heads and seed yield, according to the age of the stand, winter conditions and previous management.
Nitrogen applied as late as anthesls significantly increased the seed yield of the first harvest crop, but the after-effect on the next seed crop was not better than from an application made immediately after the first harvest. One application in spring was more effective than two in the previous summer and autumn.
Autumn defoliation influenced seed yield more strongly than the gross weight of the unthreshed crops.     

GÜLLE AS A GRASSLAND FERTILIZER (PART IV)

Further investigation into the value of gillie as a fertilizer for grassland indicates that weather affects responses. Dry weather permits good recovery of gillie N. On the other hand, on dry soil, losses of gillie N by volatilization may be increased if the quantity of sludge applied is insufficient to penetrate the soil. Cow-and-pig gillie may be more efficient than the pure-cow type as a fertilizer, the former being well balanced in N and K, whereas cow gillie requires N supplementation.     

GÜLLE AS A GRASSLAND FERTILIZER (PART III)

Results from current trials indicate that soil type, time of application and weather influence responses to applications of gulle. Over 3 sites gulle N had an efficiency of about 60% of that of fertilizer N. Best results were obtained from heavy clay soils or those containing much organic matter. Winter applications of dilute gulle to light soils under wet conditions may result in large losses of N through leaching. Generally, winter gulle applications may lead to severe losses of plants in short-term ryegrasses with associated heavy uptakes of K in spring. It is concluded that much of the gulle produced should be broadcast in winter on to swards destined for mowing in early summer. Optimum utilization of gulle calls for supplementation with fertilizer N, when the full potential of the K derived from the sludge can be exploited.     

THE CLOVER CYST NEMATODE (HETERODERA TRIFOLII GOFFART) AS THE PROBABLE CAUSE OF DEATH OF WHITE CLOVER IN A SWARD

In a lawn on sandy soil many clover patches were found, in the centres of which the clover was dead or growing poorly. A similar patch was found in another lawn. Investigation of the soil and clover roots showed that the phenomenon was probably caused by the clover cyst nematode Heterodera trifolii Goffart. Though it is likely that this damage will also occur in normal pastures, it may not manifest itself in the typical form found in lawns, since clover plants cannot expand as regularly in pastures as in lawns. Where clover is distributed irregularly in the field, a random sampling may give no real information on the clover cyst nematode population.     

野生大豆抗花叶病毒病研究

通过对800余份野生大豆对大豆花叶病毒抗性的接种鉴定,总结出适合于野生大豆抗花叶病毒病的鉴定方法。筛选出植株抗病材料2份,中抗材料11份,其余的材料都表现中等以上的感病。植株抗性与种籽传病率有一定关系但不呈正相关,选出5份种籽传病率稳定表现为零的材料。没有发现能抗大豆花叶病毒东北三个株系的材料。探讨了野生条件下不发或很少发生花叶病毒病的原因。     

大豆对紫斑病抗性鉴定方法的研究

本研究通过自然发病和人工接种鉴定了不同大豆品种对紫斑病的抗性，旨在建立大豆对紫斑病抗性鉴定方法，为大豆品种资源抗性筛选创造条件。对不同成熟期的37个大豆品种在自然条件下对紫斑病的抗性调查结果表明，大豆紫斑病的发生受气候条件、大豆成熟期和品种抗性的影响，由于避免了病害发生的有利时期，晚熟大豆品种紫斑病发生很轻或不发病。1998年和1999年，分别在防虫网室和温室人工接种鉴定45份大豆种质，两次的鉴定结果均表明大豆品种间对紫斑病的抗病性存在显著差异，但在温室条件下大豆紫斑病平均病情指数显著低于网室条件下的试验结果。为提高大豆对紫斑病抗性鉴定的准确性，建议不同成熟期的品种同期鉴定时可对早熟品种进行摘花，保证接种时接种荚荚龄一致；对接种荚进行标记；设立高感对照；鉴定为抗病的材料进行重复鉴定。     

大豆资源对斜纹夜蛾的抗性鉴定

利用网室采集的57份大豆资源的叶片,室内喂养刚孵化的斜纹夜蛾幼虫,以幼虫重为指标,鉴定大豆资源对斜纹夜蛾的抗性.综合2001年和2002年的鉴定结果,品种间、年份间、品种与年份互作差异均达极显著水平.根据标准品种分级法对抗性鉴定结果进行划分,从供试的大豆资源中筛选出4个高抗和3个高感的标准品种,可以用于抗性的分级及抗虫新基因的发掘.     

COMPARISONS OF LIQUEFIED (ANHYDROUS) AMMONIA AND AMMONIUM NITRATE AS NITROGENOUS FERTILIZERS FOR GRASSLAND

Three trials were conducted to compare liquefied ammonia and ammonium nitrate as nitrogenous fertilizers for grassland. One was at Jealott's Hill and the other two at Henley Manor, Crewkerne, Somerset. At neither centre was the response to liquefied ammonia as great as that from equivalent rates of ammonium nitrate applied in a number of split dressings throughout the season.
Split applications of liquefied ammonia were more efficient than single large dressings, but even these were not as efficient as ammonium nitrate.
The response from a single large application of liquefied ammonia in spring was superior to that from an autumn application, especially under the high-rainfall conditions at Henley Manor.
The pattern of response from split applications of ammonium nitrate was more uniform than that from a single application of liquefied ammonia. In general, the latter gave a large mid-summer cut, but fell away badly at the end of the season. These data confirm earlier findings, which also showed that liquefied ammonia was not as efficient as ammonium nitrate applied in the normal way as a nitrogenous fertilizer for grass.     

大豆霜霉病(Peronospora manschurica)抗病性遗传分析

本研究于田间以种植感病品种病粒为感染行,并以田间采集的菌孢子进行接种的方法,对1984年配制的4个杂交组合和1988年配制的4个杂交组合与5个回交组合的F_1、F_2、F_3和B_1代抗感病性进行研究。调查分析表明:大豆霜霉病是由单基因控制的简单遗传,F_1代抗病性为完全显性,F_2代抗病单株与感病单株按3:1分离F_3代出现抗病系和抗病分离系,两类系的比例为1:2。F_1代与感病亲本回交,回交一代抗病与感病单株分离比例为1:1。F_1代与抗病亲本回交,回交一代表现抗病。     

SUSCEPTIBILITY OF PERENNIAL RYEGRASS TO BLIND SEED DISEASE (GLOEOTINIA TEMULENTA)

A series of six trials with eight strains of perennial ryegrass at two levels of manuring has now been completed. Results indicate that a moderate application of artificial manures gives a high degree of control over Gloeotinia temulenta infection. The degree of infection may be influenced by climatic conditions. Each strain has a definite inherent susceptibility or resistance to the disease. The most resistant strains are the commercial strains Irish Commercial and Devon Eaver; S24 is the most susceptible, followed by New Zealand Certified Mother Seed.     

缺失SBTi—A2大豆杂交后代品系籽粒化学成分分析

对一个杂交组合后代１０个稳定缺失胰蛋白酶抑制剂（ＳＢＴｉ－Ａ２）品系及其亲本籽粒化学成分组成进行的分析比较表明，大豆籽粒中缺失ＳＢＴｉ－Ａ２对其蛋白质含量及天门冬氨酸、甘氨酸和丙氨酸含量有一定影响，表现为缺失ＳＢＴｉ－Ａ２品系显著低于高亲和双亲平均值；而对其他氨基酸和脂肪含量及脂肪酸组成基本没有显著的影响。     

大豆花叶病(SMV)若干抗性鉴定指标分析

本文通过40个大豆品种的抗大豆花叶病鉴定,阐述了种传率、褐斑率和成株抗性三个抗性鉴定指标及相互关系。结果表明:种传率、褐斑率、成株抗性分别受不同基因控制。植株感染病后,任一指标为抗性,三项指标间不存在相关性。病株种子出苗率(种子活力)下降主要受种传率影响,与褐斑率、病情指数关系不大。在田间自然传毒情况下,褐斑率、种传率均随成熟期的推迟而加重。这是原始病株(带毒种子产生的病苗)、蚜虫消长及在同一时间内,不同熟期品种生长发育期不同所致,不能反映品种本身的抗性水平。