bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth and development of the pod wall in spring rape (Brassica napus) as related to the presence of seeds and exogenous phytohormones
Authors: Srinivasan Ancha , Morgan D. G. 
Published: March 2009

SUMMARYPod wall photosynthesis is known to contribute to nearly one-third of rape (Brassica napus) seed weight. The relationship between the number of seeds and the growth of the pod wall, and the effects of single and mixed applications of gibberellic acid (GA), naphthyl acetic acid (NAA) and benzyl adenine (BA) on development of the pod wall were, therefore, examined in potted plants of spring rape under glasshouse conditions.The size and weight of the pod wall were closely associated with the number of seeds per pod, and a stronger development of tissues was observed in the presence of seeds. Application of BA alone or in combination with GA (GA + BA) to emasculated flowers induced the development of parthenocarpic pods similar in size and shape to the untreated seeded pods. NAA applied singly or in mixtures produced abnormal pods. BA enhanced cell division in all tissues while GA and NAA caused expansion of parenchyma in the mesocarp. Application of BA or GA + BA at 1–5 rather than at 11–15 days after flower opening led to the development of bigger pods. Younger pods responded more than the older ones when they were treated simultaneously. BA or GA + BA application to nonemasculated flowers on the terminal raceme delayed senescence in both basal and apical pods but it increased pod size only in the latter. The balance of cytokinins and gibberellins within a pod seems to play an important role in regulating the growth of the pod wall.
Genetic variation at five microsatellite loci in four breeds of cattle
Authors: Arranz J. J. , Bayón Y. , Primitivo F. San 
Published: March 2009

SUMMARYGenetic variation was analysed in cattle from the central area of Spain, in 1993, for the following microsatellite loci: CYP21, BOVTAU, ETH131, ILSTS002 and ILSTS005. The breeds studied were Morucha (n = 104), Sayaguesa (n = 60), Brown Swiss (n = 90) and two different populations of Avilena-Negra Iberica (n = 134 and n = 104). Morucha cattle showed the largest number of different alleles (66), whereas Sayaguesa exhibited the lowest (38). Values of number of observed alleles, gene diversity, polymorphism information content and effective number of alleles indicated that the microsatellite showing the highest variability was CYP21, followed by ETH131, ILSTS002, BOVTAU and ILSTS005.
Effects of the total, vertical and horizontal availability of the food resource on diet selection and intake of sheep
Authors: Edwards G. R. , Newman J. A. , Parsons A. J. , Krebs J. R. 
Published: March 2009

SUMMARYPlant species mixtures vary in total herbage mass (total availability) and the fractional cover (horizontal availability) and bulk density or height (vertical availability) of the component plant species. The expected diet selection response of sheep to changes in these three components of availability was tested in an artificial food environment by releasing flocks (of three ewes) onto a vegetation-free field that contained patches (plastic bowls) of preferred and less preferred sheep pellets for 15 min and observing their behaviour. One hundred patches (bowls) were laid out at equidistant intervals on a 50 × 50 m field. The patches were filled with either cereal (preferred) or lucerne (less preferred) pellets in different amounts to create in a factorial design two levels of total availability (10000 g or 15000 g of pellet in the field), two levels of horizontal availability (20 or 50 of the 100 patches contained cereal pellets, the rest contained lucerne pellets) and two levels of vertical availability (the mass of pellet in the cereal patches was either 10 or 80% relative to the mass of pellet in the lucerne patches). All patches were positioned at random in the field. Although, in all cases, the proportion of cereal pellets in the diet was higher than that expected if the sheep had foraged at random, it was sensitive to the horizontal and vertical availability of the food resource. The proportion declined as the horizontal availability declined from 50 to 20 patches, but only at 10% not 80% vertical availability. The lower proportion for this treatment combination arose because sheep ate from a higher proportion of the lucerne patches that they encountered and rejected more of the cereal patches that they encountered. Total availability did not affect diet selection. From these results it is pointed out why conclusions of diet selection experiments that do not consider how the food alternatives are distributed horizontally and vertically can be equivocal. The effect of variable levels of selective grazing in relation to changing horizontal and vertical availability of plant species on the species composition of plant communities is considered.
Progress and potential of interspecific hybrids of Lolium and Festuca
Authors: Thomas H. , Humphreys M. O. 
Published: March 2009

SUMMARYThe Lolium-Festuca complex of related species provides a wide range of variation for the development of versatile grasses adapted to meet the changing requirements of livestock farming. Various approaches have been used in order to harness the full potential of this variation. Tetraploid hybrids between the two ryegrass species L. perenne and L. multiflorum have resulted in stable and successful commercial varieties. Hybrids between more distantly related ryegrass and fescue species have demonstrated useful combinations of traits from both parents. Chromosome doubling is necessary in these hybrids to restore fertility in synthetic amphiploids. However, genetic instability can still be a problem and research is in progress to obtain tighter control of chromosome pairing. An alternative approach is to introduce a few specific traits from fescues into ryegrasses, or vice versa, using introgressive breeding procedures. This review outlines the progress already achieved in exploiting the ryegrass–fescue complex by using these various approaches and assesses the potential of hybrid derivatives.
Apex and ear development in relation to the number of grains on the main-stem ears in spring barley (Hordeum distichon)
Authors: del Moral M. B.Garcia , Tejada M.P.Jimenez , del Moral L. F.Garcia , Ramos J. M. , Togores F. Roca de , Molina-Cano J. L. 
Published: March 2009

SUMMARYApex and ear development in nine spring barley genotypes were studied at two sites in southern Spain in 1988. The genotypes were grouped into medium and early types, depending on the time from sowing to anthesis. Medium genotypes had significantly more spikelet primordia than early ones at both sites. Spikelet mortality was similar between genotypes and sites, resulting in a higher final number of grains/ear in the medium than the early genotypes.There was a positive correlation between the maximum number of spikelet primordia and the duration of three stages of apical development: lemma-, stamen- and awn-primordia. Negative correlations were observed between spikelet mortality and the duration of certain developmental phases of the ear.
Nitrogen efficiency of urea and calcium ammonium nitrate for maize (Zea mays) in humid and subhumid regions of Nigeria
Authors: Arora Y. , Nnadi L. A. , Juo A. S. R. 
Published: March 2009

SummaryField experiments on efficiency of fertilizer N applied as calcium ammonium nitrate (CAN) and urea to no-tillage maize (Zea mays) were conducted under humid (Onne) and subhumid (Mokwa) conditions. At both the locations the rate of N was 150 kg/ha.A comparison of apparent crop recovery of applied N indicated that CAN was a more effective N source than urea under subhumid conditions (Mokwa) but that urea was more effective under humid conditions (Onne). In 1981, percentages of applied N recovered by the maize crop at Onne were 28 and 50% from CAN and urea, respectively, whereas the recovery at Mokwa was 46 and 34%, respectively. Total recovery by crop and soil (0–120cm) of CAN at Onne with divided application was equivalent to that at Mokwa with single application at planting (54%). However, the total recovery of urea was much lower at Mokwa (40%) than at Onne (60%). The results in 1982 followed similar trends. Excessive N leaching loss from CAN under humid conditions and volatilization loss from urea under subhumid conditions are considered to be the reasons for poor efficiency of fertilizer N.
Computer simulation of changes in soil mineral nitrogen and crop nitrogen during autumn, winter and spring
Authors: Addiscott T. M. , Whitmore A. P. 
Published: March 2009

summaryThe computer model described simulates changes in soil mineral nitrogen and crop uptake of nitrogen by computing on a daily basis the amounts of N leached, mineralized, nitrified and taken up by the crop. Denitrification is not included at present. The leaching submodel divides the soil into layers, each of which contains mobile and immobile water. It needs points from the soil moisture characteristic, measured directly or derived from soil survey data; it also needs daily rainfall and evaporation. The mineralization and nitrification submodel assumes pseudo-zero order kinetics and depends on the net mineralization rate in the topsoil and the daily soil temperature and moisture content, the latter being computed in the leaching submodel. The crop N uptake and dry-matter production submodel is a simple function driven by degree days of soil temperature and needs in addition only the sowing date and the date the soil returns to field capacity, the latter again being computed in the leaching submodel. A sensitivity analysis was made, showing the effects of 30% changes in the input variables on the simulated amounts of soil mineral N and crop N present in spring when decisions on N fertilizer rates have to be made. Soil mineral N was influenced most by changes in rainfall, soil water content, mineralization rate and soil temperature, whilst crop N was affected most by changes in soil temperature, rainfall and sowing date. The model has so far been applied only to winter wheat growing through autumn, winter and spring but it should be adaptable to other crops and to a full season.The model was validated by comparing its simulations with measurements of soil mineral N, dry matter and the amounts of N taken up by winter wheat in experiments made at seven sites during 5 years. The simulations were assessed graphically and with the aid of several statistical summaries of the goodness of fit. The agreement was generally very good; over all years 72% of all simulations of soil mineral N to 90 cm depth were within 20 kg N/ha of the soil measurements; also 78% of the simulations of crop nitrogen uptake were within 15 kg N/ha and 63% of the simulated yields of dry matter were within 25 g/m2 of the amounts measured. All correlation coefficients were large, positive, and highly significant, and on average no statistically significant differences were found between simulation and measurement either for soil mineral N or for crop N uptake.
Determination of fertilizer requirements of potato on the basis of soil tests in the north-western hills of India
Authors: Sharma R. C. , Sharma H. C. 
Published: March 2009

summaryIn field experiments with potato conducted from 1981 to 1983 on acid hill soils of Simla, a technique was developed to work out the relative contribution of soil and fertilizer nutrients to potato production. The locations accounted for more variation in tuber yield than the fertilizer effects. The value of soil tests in explaining the variation due to locations was modified by years. On average, nitrate, organic carbon and available K explained 59, 25 and 41% of the variation. The response to fertilizer N was significant in all yea s and to K was significant in 1982 only, but that to fertilizer P was not significant in any year. The fertilizer doses of N and K were calculated both from the soil test based regression equations and the fertilizer response equations. The dose of N varied from 129 to 133 kg/ ha in different years but the response per kg N at the economic dose varied from 0·05 to 0·13 t/ha.
Varietal responses and quantitative contribution of nutrients to potato production
Authors: Sharma R. C. , Sharma H. C. 
Published: March 2009

SummaryField experiments, conducted on alluvial soil of Jalandhar during 1984–5 and 1985–6 with four rates of application each of N, P and K and four potato cultivars, Badshah, Bahar, Lalima and Jyoti, revealed significant responses to N and K. Badshah, Bahar and Lalima responded to 240 kg N/ha while Jyoti responded to 160 kg N/ha. Badshah did not respond to K. Bahar responded to 150 K/ha whereas both Jyoti and Lalima responded to 50 kg K/ha. Varietal responses to N were related to yield and crop duration while the responses to K were related to K composition of tubers. N showed inconsistent effect on percentage dry matter of tubers, but K decreased it. N increased concentration of N and P but decreased that of K.
Digestion and retention time of stained food in sheep
Authors: Fadlalla B. , Kay R. N. B. 
Published: March 2009

SummaryThe suitability of stained food and [103Ru]phenanthroline-treated food as markers for measuring dietary retention time was examined in sheep. The digestibility of oat husk, assessed by incubation of samples contained in nylon bags in the rumen, was greatly depressed by staining with brilliant green, and slightly depressed by basic fuschsin. The latter effect appeared largely to be due to boiling rather than the stain itself.When milled hay treated with both basic fuschsin and [103Ru]phenanthroline was introduced into the rumen, the mean retention time estimated with the stain was about 40% longer than that estimated with [103Ru]phenanthroline.
Percolation in colloidal soils, considered in relation to swelling and cohesiveness
Authors: Hardy F. 
Published: March 2009

(1) The results of experiments on the rate of horizontal flow, and on the rate of gain in mass, or kerosene and of water in fine and crumb fractions of certain West Indian colloidal soils, comprising three siliceous soils containing different amounts of calcium carbonate, and two lateritic soils, are described and tabulated.(2) The methods of experimentation employed were those elaborated by Green and Ampt, whose equations were found, however, not to fit the values obtained, as is to be expected.(3) The siliceous soils examined possess relatively high swelling coefficients, and their component particles, when wetted, cohere to a greater or lesser extent, depending on lime content. These properties appear to account for the relatively low rates of permeability to water in these soils. Lateritic soils, on the other hand, possess low swelling coefficients, and low cohesiveness; water percolates through them relatively very rapidly.
The inheritance of rachilla length in barley
Authors: Bell G. D. H. , Carson G. P. 
Published: March 2009

1. A study of the length of the rachilla in barley shows that it is a varietal character, although strongly affected by environmental factors.2. Rachilla length as a varietal character is affected by the density of the ear and the type of hairs or bristles borne on the rachilla.3. In six-row barleys the length of the rachilla of the lateral spikelet is greater than that of the corresponding median spikelet.4. In the absence of any of the complicating factors mentioned above, rachilla length is inherited as a straightforward quantitative character with an intermediate F1 and no signs of segregation in the F2. The number of major factors when the extremes of length are hybridized appears to be in the neighbourhood of four.5. Hybridization of “Archer” and “Chevallier” type parents has given “dominance” of length and a possible heterotic effect. Long rachilla in these crosses appears to be linked with the “Chevallier” rachilla type.
Residual effects of a slant-legged subsoiler on shoot growth and grain yield of spring barley
Authors: Hipps N. A. , Hodgson D. R. 
Published: March 2009

SummaryIn a long-term cultivation experiment comparing mouldboard ploughing, shallow cultivation and direct drilling, soil compaction was identified as a problem. Root growth was restricted and this possibly caused a decline in grain yield of spring barley. The residual effects of a slant-legged subsoiler (Trade name, ‘Paraplow’) on the growth and yield of spring barley up to 34 months after its use were measured.In 1982, soil not loosened with the ‘Paraplow’ had a grain yield of 5·16 t/ha and cultivation with the ‘Paraplow’ either 22 or II months previously had a negligible effect. Although the implement improved mean plant establishment by up to 12 plants/m2, compensatory tillering occurred in the treatments that initially had fewer plants, thus reducing differences in dry-matter production and grain yield at harvest. The long-term system of cultivation had a larger effect on grain yield than the ‘Paraplow’ did. Grain production on direct-drilled and shallow cultivated soils exceeded that after mouldboard ploughing by up to 0·55 t/ha (P < 0·05). The ‘Paraplow’ used 22 months previously increased grain yield by 0·47 t/ha on a direct-drilled soil that had become compacted.In 1983, the emergence of seedlings was low (54%) due to waterlogging of the seed bed between germination and emergence. The ‘Paraplow’ used 8 months previously increased the mean number of plants that emerged by 20 plants/m2. More seedlings survived on the soil loosened by the ‘Paraplow’ because it drained more freely than the undisturbed soil. Cultivating with the ‘Paraplow’ 11, 23 and 34 months previously increased grain yield by 0·27, 0·29 and 0·13 t/ha respectively, but the mean grain yield was only 2·70 t/ha. This improvement was caused by a greater number of grains per m2 on the soils loosened with the ‘Paraplow’. Grain weight was unaffected by cultivation system or by ‘Paraplow’ treatment.
The effect of time of sowing and water supply on the bolting and growth of lettuce
Authors: Woodman Rowland Marcus , Johnson Delphine Ainslie 
Published: March 2009

A statistical experiment was made on May King lettuce grown in a gravel soil in the unheated greenhouse to ascertain the effect of periodic sowings, two levels of water, and alternate drought and saturation with water on bolting and growth.Mature lettuces at a low level of water were darker than those at a high level. The total numbers bolting irrespective of treatment were highest in May to July, and this period coincided with temperatures above 60° F., long days, and decreasing ages from germination to bolting; the largest lettuces were harvested in October to May (excluding mid-January to late March), a period of low temperatures less than 60° F., short days, and increasing ages from germination to harvest.
A field method for evaluating frost injury to lucerne
Authors: Stout D. G. , Hall J. , Brooke Barbara , Moore T. 
Published: March 2009

J. agric. Sci., Camb. (1988), 111, 171–177The Editors regret the omission from the paper of the explanation for Plate 1, facing p. 172, as follows:EXPLANATION OF PLATEExample of visual lesions used to evaluate winter injury: (a) viable buds (arrow) are white, turgid, and may be pink tipped; (b) injured buds (arrows) are dry, discoloured, limp, or Shrivelled and dry; (c) bark is more easily peeled from injured roots; (d) injured roots are soft and easily squeezed; also note white fungal mycelium; (e) non-injured (left) root interiors are white, whereas injured (right) root interiors may be discoloured; note that discoloration from disease (left arrow) must be separated from that caused by winter injury (right arrow). The extent of leaf development at the time of sampling is demonstrated in (e).
Genetics of tannin content and its relationship with flower and testa colours in Vicia faba
Authors: Cabrera A. , Martin A. 
Published: March 2009

SUMMARYTannin content of the testa was estimated in crosses among six Vicia faba lines of diverse origin using the vanillin-HCl method. Additive genetic variance was predominant in the inheritance of tannin content. Two white-flowered parents possessed different genetic information for tannin content when the pleiotropic effect of genes for white flowers was eliminated. The genes controlling red testa (r), spotted flower (Sdp) and yellow pigment on the flower (yf) negatively influenced tannin content in the testa. Breeding for low tannin content in Vicia faba is feasible and selection can be based on plants with yellow-spotted flowers and red testas.
Digestion and chewing behaviour of young sambar and red deer consuming a low quality roughage
Authors: Howse A. J. , Semiadi G. , Stafford K. J. , Barry T. N. , Muir P. D. 
Published: March 2009

SUMMARYLow quality chaffed meadow hay, containing 10·5 g N/kg dry matter (DM), was fed to four artificially reared sambar (tropical) deer (Cervus unicolor) and four red (temperate) deer (Cervus elaphus) confined indoors in metabolism crates at Palmerston North, New Zealand, during March and April 1994. Measurements were made of DM intake (DMI), apparent digestibility, nitrogen (N) retention and the time spent eating and ruminating. Voluntary food intake (VFI), measured over days 7–11, was substantially greater for red deer than for sambar deer (67 v. 36 gDM/kgW0·75/day). Dry matter intake of red deer was then restricted, so that apparent digestibility could be better compared between the two species. Eating and ruminating time/gDMI and chews during eating/gDMI were all greater for sambar deer than for red deer. Apparent digestibility of DM, organic matter (OM) and energy were low (c. 0·42) and not different between deer species. Apparent digestibility of neutral detergent fibre (NDF) and cellulose were highest for red deer, but lignin apparent digestibility was highest for sambar deer. Both deer species lost weight and were in negative N balance. However, despite their lower N intake, sambar deer lost significantly less N and liveweight per day (– 5·6 g and – 118 g) than red deer (– 12·2 g and – 258 g). It was concluded that red deer responded to a diet of low quality roughage by increasing VFI and cellulose digestion, whilst sambar deer responded with a lower VFI but greater chewing activity, improved lignin digestion and better N conservation. Rumen mean retention time should be measured in future experiments with sambar deer and red deer fed on low quality forage diets.