ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00101.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

A series of experiments were carried out in 1954 and 1955 designed to investigate the effects of MCPA and 2,4‐D applied at different stages of growth to grasses grown for seed. Single, spaced plants were sprayed at the rate of 1·5 lb. a.e. per acre with 2,4‐D amine in 1954 and with 2,4‐D amine and ester and MCPA ester in 1955. The development of the grass growing point was used as a criterion of the developmental stages at which the plants were sprayed.Some treatments caused abnormal types of growth. S.23 perennial ryegrass and S.143 cocksfoot developed ear malformations, S.53 meadow fescue had leaf and ear malformations, while S.51 timothy showed leaf, stem and ear abnormalities.Leaf malformations developed only after spraying when the growing points showed vegetative primordia while ear abnormalities usually appeared after treatment at most early stages of development. Stem malformation in timothy occurred after spraying at all stages in 1954, but only at the vegetative stages in 1955.The percentage of abnormal ears in a random sample of tillers in all but one case fell as the growing point developed and most damage occurred after treatment when the apex was at the vegetative stage. Normally, treatment when glume ridges were visible on the apex produced no significant difference between the number of abnormal ears in the treated and untreated plots.The results suggest that the chemicals act on that part of the apex which is just beginning its development but is not yet visible as a protuberance on the apex.The type of abnormalities occurring in grasses as a result of spraying with growth regulating weedkillers is similar to those found in cereals after similar treatment.Provided that the chemicals are applied in the 4 to 5 weeks prior to ear emergence the amount of malformation occurring in the grasses will be

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00102.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

Systems of calf grazing were compared in preliminary experiments during 1954 and 1955. Hereford colour‐marked beef calves in the post‐weaning stage were used, all calves having been reared on the nurse‐cow system in loose boxes.The results indicate that autumn‐ and winter‐bom calves can make good progress at pasture during their first summer, husk‐free ground being one of the most important requirements in the production of well

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00103.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00104.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

When livestock are used to measure the output of pasture, the potential output of the animal is on occasions lower than that of the grassland so that this may determine the yields of animal products which are obtained, regardless of pasture type and treatment. The implications of this are discussed in relation to the interpretation of data of grassland evaluation, and also in relation to maximum utilisation of grass.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00105.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

S.48 timothy plants were induced to form proliferating inflorescences by exposure to 2–4 weeks of long days followed by a return to short days. Serial micro‐dissections showed that the lemma enlarges to resemble a leaf but that glumes, palea and all reproductive organs are also present and perfectly farmed. At a later stage a vegetative shoot bearing several foliage leaves, axillary buds and root initials is formed, presumably as a continuation of the rachilla.The production of proliferations by insufficient exposure to photoperiods favourable for flowering is discussed. Proliferations may occur spontaneously in many normally seed‐setting grasses, but in a number of species this form of growth is genetically

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00106.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

Eight strains of white clover were compared under a cutting treatment over a three‐year period. The medium‐leaved, persistent strains S.100, S.100 Nomark, Kersey, New Zealand CM. and P.P. generally gave the highest yield of clover, but this was counterbalanced by an increased yield of unsown species in the plots of wild white clovers S.184 and Kent.The unsuitability of Ladino clover for British conditions was shown by its lack of persistency and poor yield. The new strain S.100 Nomark gave a similar total yield to S.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00107.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

A study was made of the local effects on yield and botanical composition of the herbage of cattle dung and urine applied to permanent pasture as simulated defaecations and urinations.A single application of urine had a negligible effect upon botanical composition. In the 2‐ft.‐diameter circle around dung patches there was an increase in cocksfoot, creeping bent, red fescue and white clover, and a decrease in herbs.Urine patches were neglected by grazing stock for short periods only. Herbage around dung patches was neglected for a period varying from 13–18 months. The effect of this neglect was to restrict the spread of white clover around dung patches in comparison with similar plots kept short by cutting.Yield response to urine in the area of deposition lasted for two cuts following application, response to dung for four cuts. An increase in crude‐protein content of the herbage was recorded only in samples taken one month after application of dung or urine, and not later.Increases in crude‐protein yield following spring applications of dung or urine were greater than those following autumn applications. The inferiority of autumn applications may be attributed to winter leaching of

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00108.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00109.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

Three trials in which metabisulphite was used as a silage additive are described and the results discussed.The data from two small‐scale trials suggests that metabisulphite and molasses each have a similar effect on the quality of the silage produced, and that wilting appeared to be more effective than either of these two additives.A comparison of silages in two large‐scale trials indicates the necessity for uniform distribution of the metabisulph

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1958.tb00110.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY