bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on character association in potatoes
Authors: Gaur P. C. , Kishore H. , Gupta P. K. 
Published: March 2009

SUMMARYThe phenotypic, genotypic and environmental correlation coefficients were calculated for 13 morphological and tuber quality characters, 17 of 78 possible combinations were found to be significant. Tuber yield was positively associated with average tuber weight and with total tuber dry matter per plant. Average tuber weight was negatively associated with number of tubers per plant and with most of the quality characters. The indices for selection for tuber yield were computed using the yield components and yield only. It was observed that the selections based on tuber yield itself are likely to be superior to those based on yield components. However, an index involving the yield components and the yield was found to be most efficient.Among the tuber quality characters, percentage tuber dry matter showed significant positive association with the percentage alcohol-insoluble solids (AIS) and with the percentage of starch in fresh tubers, and a negative association with the percentage of protein in tuber dry matter. The associations between percentage of starch in fresh tubers and the percentage of starch in tuber dry matter, between percentage of starch in AIS and the percentage of starch in tuber dry matter and between percentage of protein in fresh tubers and the percentage of protein in tuber dry matter were also found to be significant and positive.To increase tuber yield it is necessary to break the negative linkage between its two components. High total tuber dry matter per plant can be brought about by selecting for high tuber yield. For the improvement of tuber quality together with tuber yield, the selection for yield based on a large number of tubers is likely to be useful.
Dried potato products for egg production: statistical analysis of a laying experiment
Authors: Bolton W. , Hale R. W. 
Published: March 2009

An experiment involving twelve pens of twenty-five pullets demonstrated that two types of dried potatoes compared favourably with cereals, as regards their effects on egg production, when up to 42½% of each product was included in the mash.The records of the experiment, as regards (a) the number of eggs laid in 12 months, (b) the mean weight of eggs during the year, and (c) the change in live weight during the year, were studied by analysis of variance, using the approximate method of Yates (1933) for obtaining standard errors of pen means from the variance within pens. Similar analyses of the number of eggs laid in the month were carried out for each month separately. The latter analyses indicated the months in which increased production was obtained from the superior rations, and showed that duplicate pens had reacted similarly to the experimental feeding. The results of the statistical analyses are set out in some detail as an example of method.
A study in soil cultivation. The effects of varying soil consolidation on growth and development of rain-grown cotton
Authors: Heath O. V. S. 
Published: March 2009

1. Experiments were carried out in four seasons at Barberton, South Africa, occupying approximately 2¼ acres of ground. Three soil treatments were used, viz. Normal (N), Compressed (C) and Grubbed (loosened) (G).2. Measures of consolidation of the soil were made with a specially designed apparatus, and large differences established (pp. 516–520).3. Estimations of water content and nitrate content were carried out. No great differences were found (pp. 520–524).4. Fortnightly samples of the plants were taken, from which numerical data were collected designed to estimate morphological development (primary data, pp. 526–529).5. Derived data on net assimilation rate, relative leaf-growth rate and efficiency index were calculated (pp. 529–533).6. Growth in total dry weight was found to conform approximately with an exponential law up to the time of flowering. Up to this stage also net assimilation rate was found to remain constant.7. Growth differences between treatments were related to variation in net assimilation rate only (p. 531).8. The results were analysed statistically. Significant results alone are emphasized.9. In all respects growth and development on the consolidated soil was more rapid than that on the grubbed soil, normal being generally intermediate.10. The results are discussed with reference to the question of nitrogen supply, water supply and aeration of the soil.
Nitrogen metabolism in the ovine stomach: 2. Factors influencing ruminal ammonia levels in sheep maintained on different diets
Authors: Harrop C. J. F. 
Published: March 2009

SUMMARYFactors which could be expected to influence levels of ammonia in the rumen were compared in sheep maintained on diets providing 11·4 or 20·7 g N/day.The ruminal fluid volume in sheep given the lower-N ration was 78% of that in sheep maintained on the higher-N diet. The effect of this in diluting rumen ammonia from recycled urea is discussed.Ruminal urease activity was higher in sheep given the lower-N diet, and was confined to the particulate fraction of rumen liquor in animals given either diet. At least 95% of the maximum activity occurred in the range of pH 5·4–7·05, and pH 6·0–7·25 in sheep maintained on the lower- and higher-N diets respectively. Small variations in activity were observed between the morning and evening meals.In vitro rates of net ammonia production in samples of rumen liquor were similar in sheep given either diet; a positive correlation with the initial ammonia concentration was evident. Net utilization of ammonia was detected in some experiments in samples from sheep maintained on the lower-N diet. Starvation for 1 day was associated with increased rates of production and initial concentrations of ammonia.Cellulose, as cotton thread, was digested at similar rates in vivo in sheep given the different diets. This is discussed in relation to the demand for ammonia by cellulolytic bacteria.
Four-year leys: the inclusion of red clover: first year management
Authors: Garner F. H. , Sanders H. G. 
Published: March 2009

1. Two experiments have been carried out on the Cambridge University Farm to test the desirability of including late-flowering red clover in the seeds mixture in the case of a 4-year ley, and to compare grazing with cutting for hay in the first harvest year.2. The majority of the red clover survived for the first 2 years, during which it increased the yield of dry matter very markedly; it did not lead to any reduction of yield in the last 2 years. By producing an early cover of the ground red clover checked the encroachment of weeds; although it reduced the proportion of wild white clover in the herbage in the later years, the reduction was not serious.3. Where the young plants were well established at the time, and normal weather conditions were experienced, grazing was definitely preferable to cutting for hay during the first harvest year. Where the plants were slow in establishing themselves, and in a superlatively dry spring and summer, grazing checked the development of the sward too much, and cutting for hay gave much better results.
Ovulation and the descent of the ovum in the Fallopian tube of the mare after treatment with gonadotrophic hormones
Authors: Day F. T. 
Published: March 2009

1. In mares which had a follicle of a sufficient size in the ovaries, in most cases the intravenous injection of 1000 mouse units or over of pregnancy urine extract caused ovulation at any time in the oestrous cycle.2. In those mares which were in oestrus at the time of injection, ovulation occurred 22–30 hr. after injection, and the length of oestrus was reduced from 7 and 9 days to 3 days.3. In those mares which were not in oestrus when injected ovulation occurred 30–60 hr. after injection without the appearance of any symptoms of oestrus.4. Normal ovulation occurred after these injections, and in one case the ovum was recovered from the uterine end of the Fallopian tube about 95 hr. after ovulation, and 138 hr. after injection.
Variation in the protein intake of sheep in relation to wool growth
Authors: Fraser A. H. H. , Roberts J. A. Fraser 
Published: March 2009

Summary1. Two lots of twenty sheep each were fed indoors on rations known to produce satisfactory growth. The calorific value of the two diets was the same. One lot received 52 per cent, more digestible protein than the other. The diet of the low protein group was protein deficient according to the calculations of Wood.2. The sheep were shorn at the beginning of the experiment and again at its conclusion. Fibre measurements were made on samples taken at the same two periods from the same body area. The fleece and fibres grown during the experimental period were compared in each case with the fleece and fibres grown during the pre-experimental period. The fibre measurements included fineness, length and fibre weight.
The fungicidal properties of certain spray-fluids, X. Glyceride oils. (With two text-figures.)
Authors: Martin H. , Salmon E. S. 
Published: March 2009

Summary1. The fungicidal action of vegetable oils on the conidial stage of the hop powdery mildew, Sphaerotheca Humuli (DC), Burr., is a property common to glyceride oils. When applied with 0·25 per cent. Agral I, the various samples of vegetable and animal oils examined, with the exception of castor oil, proved fungicidal at a concentration of 0·5–1·0 per cent.2. The fungicidal action of glyceride oils is associated with the glyceride structure and, in the presence of Agral I, is unaffected by the presence of those impurities of the oil which are removed by refinement.3. Glycerol, at 4 per cent., is not completely fungicidal and, under the conditions of the experiments, causes leaf injury; oleic acid, at 1 per cent. is phytocidal; triolein, prepared by synthesis from glycerol and oleic acid, is fungicidal at 0·5 per cent. and causes no injury to the leaves.4. The fungicidal properties of glyceride oils are affected by the type of emulsification used and the stable emulsions produced by the twosolution oleic acid method are less effective than the unstable emulsions obtained by agitation with dilute Agral I solutions.
A simplified prediction equation for reactive solute transport in soils
Authors: Gupta S. K. , Pandey R. N. 
Published: March 2009

SUMMARYA general equation for predicting the movement of interacting and non-interacting solutes is proposed. Equations to predict the leaching fractions and mean displacement depth of linearly adsorbed solutes have been derived from the solution of the general equation. A simple equation which considerably reduces the experimental and analytical work has also been derived to evaluate the adsorption coefficient. The predicted adsorption coefficient compares favourably with published data.
Effect of light and temperature on wool growth
Authors: Elsherbiny A. A. , Eloksh H. A. , Elsheikh A. S. , Khalil M. H. 
Published: March 2009

SummaryWool samples were collected from 39 rams representing five breed groups of sheep: Merino (M), Ossimi (0), and the crosses between them, viz. ¾ Ossimi–¾ Merino (¾ O), ½ Ossimi–½ Merino (½ O) and ½ Ossimi–¾ Merino (¼ O) maintained at Sakha Experiment Station, Kafrelsheikh, Egypt, with the objectives of detecting the effect of the seasonal changes in normal light rhythm and temperature on wool fibre length and diameter. Animals were divided into two light treatments groups, the first consisting of four animals from each breed kept under continuous dim light conditions throughout the year and the second of three animals from Ossimi and four from each breed group kept inside an open pen free to sunlight and shade zones under daylight rhythm throughout the year. It was found that fibre length as well as fibre diameter in normal light exceeded that in dim light except in winter time. Breed groups showed different responses to the absence of light especially the Ossimi and the ¾ O whose fibre lengths were most affected. The breed groups had larger fibre diameters in normal light than in dim light except Merino and ¼ O. Seasonal changes in temperature had a highly significant effect on fibre length but not on fibre diameter. Higher temperature coincided with lower increases in fibre length. Season to season variation in wool growth seemed to suggest that the number of light hours per day and atmospheric temperature counteracted each other resulting in a non-significant seasonal pattern.
Water relations of winter wheat: 1. Growth of the root system
Authors: Gregory P. J. , McGowan M. , Biscoe P. V. , Hunter B. 
Published: March 2009

SummaryThe production of root axes and the growth of the root system are reported for a commercially grown crop of Maris Huntsman winter wheat. Soil cores were extracted on 17 occasions during the growing season permitting a detailed study of root length and root dry weight with depth and time.Production of seminal root axes was complete by the beginning of March when all plants possessed six (occasionally seven) axes which persisted throughout the life of the crop. Nodal axes were produced continuously from mid-February until late May and finally numbered approximately 20 stem nodal axes per main stem. Total root dry weight increased exponentially until the beginning of April and then almost linearly to reach a maximum of 105 g root/m2 field in mid-June (anthesis). After anthesis, total root dry weight decreased but root growth continued below 80 cm. From April onwards, approximately 65% of the total root dry weight was in the 0–30 cm layer.
Equations to predict leaching of soluble salts in saline soils
Authors: Pandey R. N. , Gupta S. K. 
Published: March 2009

SummarySimple mathematical models to predict leaching fractions and mean displacement depths of salts either uniformly distributed in the soil profile or surface applied have been derived from the solution of Peck's differential equation of salt balance. Predictions from these models are comparable with those obtained from Burns' equation and fit published data well.
Canopy apparent photosynthesis, respiration and yield in wheat
Authors: Shuting Dong 
Published: March 2009

SUMMARYField experiments explored the relationship between canopy apparent photosynthesis (CAP) and grain yield and examined the effect of plant population density on CAP. Two cultivars of wheat were grown at five plant population densities in 1986 and 1987 in Taian, China. Measurements of CAP were made at intervals during the growth period by placing a large plastic-covered chamber over a 0·7 m2 segment of the canopy and measuring CO2 depletion with infra-red gas analysers for 1–2 min at c. 25 °C around noon when solar radiation was > 1100 umol/m2/s. Canopy respiration (CR) rates were measured by covering the whole chamber with a black screen in the daytime. Calculations of CAP and CR were made using the chamber volume, air temperature and changes in CO2 concentration over time and expressed on a land area basis.Maximum values of CAP and CR were 4–6 g and 2–3 g CO2/m2/h, respectively, at the anthesis stage, decreasing with age during grain filling. The decrease was more rapid at the high than at the low population density. The difference in CAP between plant densities before booting and after anthesis could be attributed to reductions in leaf area index (LAI) and photosynthetic rate.Grain yield also differed between plant population densities, the range being from 5250 to 7500 kg/ha in both years. Grain yield and 1000-grain weight were positively correlated with CAP during grain filling (r = 0·78 and 0·99, P < 0·01, 8 D.F.). Effects of plant density on CR were highly significant, but CR was not related to yield (r = 0·50).
Digestion and rumen metabolism of red clover and perennial ryegrass/white clover forages by red deer
Authors: Freudenberger D. O. , Burns C. J. , Toyokawa K. , Barry T. N. 
Published: March 2009

SUMMARYRed clover (RC) and perennial ryegrass (PRG)-based forages were cut fresh during late spring/early summer and fed at similar levels of dry matter (DM) intake to rumen fistulated castrated red deer kept indoors in metabolism pens. RC contained higher concentrations of total N and non-protein cell contents than PRG and lower concentrations of fibre. Rumen pool size and fractional outflow rates of liquid (13·3 ν. 15·1%/h) and of paniculate matter (2·5 ν. 3·9%/h) were lower for deer fed RC than PRG. Apparent digestibility of energy and fibre, rumen fibre fractional degradation rate and rumen fractional disappearance rate of non-protein cell contents were all higher for RC than for PRG deer. Nitrogen retention was similar for deer fed both forages. However, the concentration, pool size and outflow of ammonia from the rumen, together with urinary N excretion, were all much greater for deer fed RC than those fed PRG. The acetate: propionate ratio in rumen volatile fatty acids (VFA) was lower for the RC than the PRG group. It was concluded that the greater fibre digestion in deer fed RC was due to a faster rumen fractional degradation rate and a longer particulate mean retention time in the rumen, and that the very rapid outflow of water from the rumen relative to particulate matter in deer fed RC (5·5:1 ν. 3·8:1) may explain why deer are not susceptible to rumen frothy bloat when grazing RC. One reason for the greater voluntary feed intake (VFI) of deer grazing RC than those grazing PRG may be due to its greater concentration of protein and non-protein cell contents and their more rapid degradation and removal from the rumen.
Crop production and water-use. II. The development and validation of a water-use model for sugarbeet
Authors: Hamer P. J. C. , Carr M. K. V. , Wright E. 
Published: March 2009

SummaryAs a prerequisite for developing crop-yield/water-use functions for sugarbeet using the results of historical irrigation experiments, it was necessary to develop a water-use model which could operate with a limited data set. The general form of this model has been reported by Wright et al. (1994). In this paper the development and validation of the model for the sugarbeet crop is described.The canopy was modelled in terms of the leaf area index and the relative interception of incoming solar radiation using functions based on thermal time and time. Four phases of growth were identified: emergence, slow-growth, fast-growth and full-canopy. An empirical drought factor was included to allow for the effects of water stress on canopy development during the slow- and fastgrowth expansion phases. Root development was described using a three phase model: initial (temperature dependent), linear and maximum depth (both time dependent).Independent data previously reported from Broom's Barn Experimental Station were then used to validate the model in terms of its capacity to predict crop canopy development, with and without drought stress, soil water extraction at different depths and soil water deficits during the season. The study confirmed the validity of the model for predicting the water-use of sugarbeet.
The location and effects of genes modifying the response of wheat to the herbicide difenzoquat
Authors: Leckie D. , Snape J. W. 
Published: March 2009

SUMMARYSingle chromosome substitution lines of hexaploid wheat were developed using a variety resistant to difenzoquat, Chinese Spring, as donor and a susceptible variety, Sicco, as recipient, and were used to identify chromosomes carrying genes which modify the responses of these varieties. It was found that chromosomes 3B and 5D from Chinese Spring might act to reduce the amount of damage caused by the herbicide in the presence of the allele for susceptibility at the Dfql locus. The intermediate response to the herbicide, which is shown by some commerical varieties, was also investigated using a backcross reciprocal monosomic analysis. In these varieties, the allele at the Dfql locus determining the reaction to the herbicide was shown to be similar to that of the susceptible variety Sicco. It is, therefore, probable that the responses of intermediate varieties are due to the effects of modifier genes increasing resistance.
Response of pearl millet (Pennisetum americanum) to short-term flooding in a moderately sodic soil under field conditions
Authors: Sharma D. P. , Swarup A. 
Published: March 2009

SUMMARYA field study in India in 1987 evaluated the effects of flooding at either tillering (25 days after sowing) or flowering (50 days after sowing) or at both on growth, yield and mineral composition of Pennisetum americanum L. Leeke in a moderately sodic soil (pH 8·5, exchangeable Na 18%).Flooding for 1, 2, 4 or 6 days at tillering or flowering significantly reduced tillering, plant height, dry matter content, ear length and 1000-grain weight and resulted in a 6·3, 150, 21·6 or 26·6% reduction in grain yield, respectively. Flooding decreased oxygen diffusion rate, restricted root growth and decreased ion uptake, especially of N, P, K and Zn, and led to higher absorption of Na, Fe and Mn. The detrimental effects were greater when the crop was flooded at both stages.
Phenological development in bambara groundnut (Vigna subterranea) transferred from 14 to 11 h photoperiods
Authors: Linnemann A. R. 
Published: March 2009

SUMMARYAspects of the photoregulation of phenological development in bambara groundnut were studied in a glasshouse experiment in The Netherlands. The influence of a 14 h photoperiod (which retards podding) during a period of variable length prior to an 11 h photoperiod (which induces podding) on flowering, yield and on the position of pods on the plants was determined. The third generation of three plants of genotype ‘Ankpa 4’ from Nigeria was used as the split-plot factor in a split-plot design with three replicates. The main plots were four daylength treatments: a period of 21, 28, 41 or 54 days under the 14 h photoperiod before transference to the 11 h photoperiod. Plants transferred after 28 or more days started flowering sooner the earlier they were transferred. Plants transferred after 21 and 28 days began flowering at the same time (51 days after sowing), thus indicating juvenility. At harvest, 135 days after sowing, the total seed dry weight per plant was higher for plants transferred after 41 and 54 days than for plants transferred after 21 days. Plants transferred after 28 days gave an intermediate value. Most (79–91%) pods were produced on branches that developed on nodes 1–4 of the main axis. There were no differences in the fractional distribution of the pods along the main axis in plants transferred after 28 or more days. Pods of plants transferred after 21 and 28 days were more evenly distributed over the nodes of the first two primary branches than pods of plants transferred after 41 and 54 days. Plants of the latter treatments produced their pods more towards the tips of the branches and concentrated on two neighbouring nodes (nodes 5 and 6 for plants transferred after 41 days and nodes 6 and 7 for plants transferred after 54 days). Delaying the induction of podding in this experiment therefore resulted in higher seed yields per plant and a more synchronized development and hence maturity of pods.