The effect of some pre-treatments on proteolysis during the ensiling of herbage

Two experiments were carried out to examine the nitrogenous changes occurring in herbage during harvesting and ensiling. In the first, ryegrass-clover was wilted rapidly in the laboratory (6 h) and in the field under good (48 h) and poor (48 h and 144 h) weather conditions. Protein breakdown and ammonia formation were negligible in herbage wilted rapidly and it was only when the crop was exposed to a prolonged wilt in humid conditions that appreciable proteolysis occurred. In the second experiment ryegrass-clover was ensiled in laboratory silos after treatment with varying levels of formic and sulphuric acids. An additional treatment included herbage inoculated with a mixture of lactic acid bacteria and glucose. The silos were opened after 4 and 50 d and samples were analysed for protein-N, ammonia-N, water-soluble carbohydrates and organic acids. There was a high negative correlation between level of addition of either acid and the degree of proteolysis and deamination. Even at the highest levels of formic acid (7·7 g per kg) and sulphuric acid (4·0 g per kg) additions, however, about 45% of the original herbage protein was degraded after 50 d in the silo. The inoculum treatment was also effective in reducing proteolysis, the effect after 50 d being comparable with formic acid applied at a rate of 4·1 g per kg.     

Variations in composition of pasture herbage

Changes in the chemical composition of pasture samples from five dairy farms were observed over a 2-year period. Many of the minerals were at their lowest concentration in samples taken in the spring and early summer. At these times the concentrations of P, Mg and Na were often less than sufficient to meet the calculated requirements of the dairy cow fed on pasture alone. Cu and Co concentrations in the herbage were also generally low relative to the needs of the dairy cow.     

The digestibility of diets containing processed dried lucerne by sheep and cows

A series of trials was conducted to compare the digestibility of organic matter in castrated male sheep and non-lactating and lactating cows given diets containing lucerne cobs. Similar digestibility coefficients were determined when sheep and non-lactating cows were given hay and lucerne cobs, but lactating cows digested diets of hay, lucerne cobs and concentrates less well than sheep. It is concluded that if sheep are used in digestibility trials with diets containing processed lucerne and concentrates intended for milking cows, appreciable errors of prediction of digestibility of organic matter may arise.     

Dalapon resistance at an early seedling stage in Lolium perenne

The inhibitory effect of the herbicide dalapon on germination and shoot elongation was evaluated in two perennial ryegrass cultivars, Melino RvP and Cropper. These cultivars had been shown to be dalapon resistant and susceptible, respectively, in a previous comparison of 14-week-old plants. Dalapon (10^-2 and 10^-3 m) significantly reduced rates of germination and shoot elongation to the same extent in both cultivars. It is suggested that the effects of dalapon on germination and shoot elongation during the first 9 days of development are not indicative of levels of resistance in more mature plants.     

Some Effects of the Plantation of Conifers on a Freely Drained Lowland Soil, Forest of Dean, U.K.

Acid brown soils under 50-year-old conifer plantations are comparedwith those at a control site under the previous vegetation ofmixed deciduous woodland. The soils under the conifers showsignificant signs of podzolization and associated with this,evidence of structural breakdown. The implications of thesechanges are briefly discussed.     

Rouging wild oats

Over a period of three seasons the effectiveness of rouging wild oats in cereal crops with a patented herbicide glove was compared with hand pulling. Time spent by one operator in searching for the wild oats was found to remain relatively constant at 1.25–1.5 h/ha over a wide range of wild oat populations. If this searching time was excluded, treatment of the actual wild oat panicles was about three times as fast with the glove (1450/h) as by hand-pulling (538/h). The implications of this and of the saving in time spent in carrying off and disposing of’pulled’ wild oats are discussed. Solutions of 5% and 10% w/v glyphosate applied to either the stem or the panicle of the wild oats prevented the formation of viable seed. It did not, however, prevent some inviable wild oat seed appearing in the harvested grain; without additional cleaning these would have prevented the sale of the grain for seed but not into E.E.C. intervention. Extirpation de la folle-avoine Durant one période de trios saisons, les auteurs ont compare l'efficacité de l'extirpation de la folle avoine dans des cultures de céréales au moyen d'un gant herbicide breveté et en pratiquant I'arrachage manuel. Le temps passé par un opérateur à la recherche des pieds de folle-avoine s'est révélé relativement constant: 1,25 à 1.5 h/ha pour un large échantillonnage de populations de folle-avoine. Si l'on enlève ce temps de recherehes, I’operation sur les panicles présentes de folleavoine a été environ 3 fois plus rapide avec le gant (1 450/h) quä la main (538/h). Les conséquences de ce résultat et de lëconomie de temps passéâ transporter et â détruire les plants de folleavoine arrachees sont discutées. Des solutions de glyphosate à 5% ou 10% (poids pour volume) appliquées soit sur la tige soit sur la panucle des follesavoines ont empèche la formation de semences viables. Toutefois, cette opération n'empeche pas la présence d'un certain nombre de semences non viables de folle-avoine dans le grain recolté; sans nettoyage supplémentaire, ces graines d'adventices auraient empéché la commercialisation du grain récolté comme semence, mais pas à I'intérieur de la C.E.E. Manuelle Bekämpfung von Flughafer über drei Vegetationsperioden wurde die effizienz der manuellen Flughaferbekämpfung in Getreidebestanden mit hilfe eines ‘herbizid-Handschuhs’ verglichen mit dem Aufwand beim Jäten von Hand. Die von einer Arbeitskraft benötigte Zeit für das auffinden der Flughaferpflanzen blieb über einen weiten Bereich der Besatzdichte an Flughafer mit 1,25–1,5 h/ha verhältnismässig konstant. Lässt man diesen Zeitaufwand uberücksichtigt, dann erfolgte die Behandlung der Flughaferrispen mit dem Handschuh etwa dreimal so schnell (1450/h) wie durch Jäten von hand (538/h). Die hieraus sowie aus der Ersparnis an Zeit, die sonst für Abtransport and Ablagerung der gejateten Flughaferpflanzen benötigt worden wäre, zu ziehenden Folgerungen werden diskutiert. Lösungen von 5% oder 10% (Gew./Vol.) Glyphosat entweder am Halm oder an der Rispe der Flughaferpflanzen angebracht. verhinderten die Bildung von keimfahigen Samen. Sie konnten aber nicht verhindern. dass dem Getreide nach der Ernte einige nicht keimfähige Flughafersamen beigemengt waren. Hierdurch bedingt wäre ohne zusätzliche. Reinigung ein Verkauf des Getreides als Saatgut nicht möglich gewesen, wohl aber ein Verkauf an die EG-Interventionsstelle.