摘要:

AbstractA number of series of related aliphatic and aromatic amides have been examined as pre‐emergent herbicides in both laboratory and greenhouse tests using wheat, cabbage and rye‐grass as test plants.Some of these compounds were found to show specific activities at low dosage rates. Rates of hydrolysis of certain of the compounds were determined and the activity of the parent acids in standard tests for plant growth regulating activity was assessed. No general relationship could be drawn between pre‐emergent herbicidal activity and chemical structure although the importance oforthosubstitution in the benzamide and phenylacetamide series was established.In some cases selectivity was found to be greatly affected by slight structural modifications.o‐Chlorophenylacetamide, for example, was markedly effective against cabbage at 10 lb./acre but not against wheat, whereas the opposite type of selectivity was shown by itsNN‐dimethyl‐analogue. These two compounds ando‐chlorobenzamide ando‐toluamide were further examined elsewhere using a wider range of crop plants and weeds and useful selective herbicidal properties were found. It is suggested that some of the compounds might well be examined further under f

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101101

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe leaching of nitrate was studied by percolating water through columns of clay loam and sandy loam soils.The light soil lost nitrate more quickly than the heavy soil. For both heavy and light soils the rate of loss of nitrate from the soil into the leachate was initially greater from a coarse fraction (2‐10 mm.) than from the unseparated soil. For the heavy soil a fine fraction (<2 mm.) initially lost nitrate most quickly but ultimately the most nitrate was leached from the unseparated soil. When water was added slowly at the top of columns of unseparated soils until the bottom became wet, nitrate moved downwards, but not uniformly, as for both soils there was a minimum in the nitrate concentration near the bottom of the column. It is suggested that drainage water flows initially over the structural units, and not through the mass of soil until it is completely saturated, so that nitrate is first lost from the surface of the structural units and later from the soil mass as a whol

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101102

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe effect of various rates of application of superphosphate between 0 and 4 cwt. P2O5per acre on the yield and growth of potatoes was studied in a very wet season (1954) and a dry one (1955). Although shoot yield was stimulated by dressings up to 2 cwt. of P2O5per acre on the ‘low P’ soils, root and tuber dry matter were not further increased by dressings above 0.66 cwt. of P2O5per acre. on ‘high P’ soils superphosphate applications had little effect on shoot yield but delayed tuber development and depressed the final yield of tuber dry matter.There was a positive correlation between P uptake and yield of tuber dry matter on the low‐P soils and a negative one on high‐P soils. It is suggested uptake of P2O5per acre at the 12‐week stage for optimum tuber production was 30‐35 lb. per acre and that phosphorus toxicity occurs at higher l

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101103

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractExperiments have been made with cane molasses and with beet molasses as substrates for the cultivation of the fat‐producing mouldsAspergillus nidulansandPenicillium soppii.Satisfactory yields of fat up to 16 g./l. on a cane molasses medium supplemented with salts and up to 11.8 g./l. on an unsupplemented beet molasses medium were obtained with A.nidulansin static culture, but in shaken cultures prepared with molasses media this mould produced little fat in static and in shaken cultures prepared with sucrose‐salts mediaP. soppiiproduced 21.6 g. of fat/l. and 8.1 g. of fat/l. respectively. in static cultures on supplemented and unsupplemented cane‐molasses mediaP. soppiiproduced about 18 g. of fat/l., while in static cultures on beet molasses media, whether fortified by salts or not, the yield was 22 g./l. WhenP. soppiiwas grown in beet molasses media with agitation the highest yield of fat was 6.2

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101104

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe saturated vapour concentrations at 35° of 21 organo‐mercury compounds have been determined by static and dynamic methods and the corresponding partial pressures derived. For 14 of these compounds, together with mercury and mercuric chloride, values at 25° and 45° have also been determined and the constants in the linear pressure‐temperature relation calculated. Some correlation between chemical constitution and vapour pressure has been

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101105

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe changes taking place in egg shells during the course of incubation have been studied, using histochemical tests and plastic embedding techniques. It has been confirmed that the membrane comes off all the shell, apart from that over the air space, by about the 15th or 16th day. the membrane does not come away cleanly from the shell but carries with it the ends of the mammillary knobs, including the mammillary cores. At the end of incubation there is still a great deal of calcium carbonate present on the membrane. These results are discussed in relation to those of previous workers on the subject.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101106

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe development of brown pigmentation, the disappearance of reactants and changes in the fluorescence of reaction mixtures of ribose with individual compounds present in cod muscle extractives have been measured. These data are discussed, together with chromatographic evidence, in relation to general ‘browning’theory. By reference to the known composition of the extractives of fresh and of chill‐stored muscle, the relative importance of the different nitrogenous compounds in the early stages of the ‘browning’of dehydrated and of salt cod is p

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101107

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractComplete exclusion of oxygen prevented any further change in the flavour of freeze‐dried plasma stored at 25°. the partial or complete destruction of plasma glucose before drying or an increase in the amount of glucose before drying had no effect on the development of fishiness during storage in air. the rate of development of fluorescence and the loss of glucose and free amino nitrogen in freeze‐dried plasma during storage were influenced by oxygen, glucose and water content. A rapid increase in the intensity of fluorescence required the simultaneous presence of both glucose and ox

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101108

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe effects of a change in the moisture content of a soil (from approximately half to approximately one‐third of the water‐holding capacity) on the composition of soil solution and nutrient uptake of barley seedlings was examined.The P, NO3− and Ca contents of the soil solution (per unit dry soil) increased with the water content. the % increases differed for each nutrient (the general order being NO3−>P, K>Ca) and with the manurial treatments. Changes in the actual concentration of nutrients (per unit volume of soil solution) were generally comparatively small.The pH of the soil solution was not affected by the change in water supply although fertilisers produced differences of over 2 pH units.The uptake of nutrients by barley per unit weight of soil and the dry matter produced in the seedlings were greater with the higher water supply, the proportional (%) increase differing with the nutrient (19–77%) m the general order Ca>K, Mg>P>N. the manurial treatments affected the nutrient intake more at the lower level of wat

ISSN:0022-5142    

DOI:10.1002/jsfa.2740101109

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY