bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fibrous root growth and water use of sugar beet
Authors: Brown Kay F. , Biscoe P. V. 
Published: March 2009

SUMMARYDevelopment of the fibrous root system of sugar beet was studied by washing soil samples taken from field experiments through the growing season. At the beginning of June the root system was still poorly developed but during June there was rapid proliferation. In the top 70 cm there was only little further increase in root density after the end of June. Below 70 cm root density increased up to the end of August. Throughout the season fibrous root density decreased with depth. Despite the origin of the lateral roots from two grooves on the storage root, fibrous root distributions at each depth around individual plants were essentially uniform from mid-June onwards. In the absence of nitrogen fertilizer, fibrous root development exceeded that of a crop given fertilizer, particularly at depths greater than 50 cm early in the season. The maximum value of root density was 2·8 cm/cm3 soil recorded in the top 10 cm in mid-September. Compared with published data for other crops, the sugar-beet root system was sparser than that of winter wheat or maize but denser than that of a soya bean or cassava.Soil water content was measured with a neutron probe. Inflows to roots were calculated from soil water content changes in different soil layers. In the top 30 cm, inflows ranged up to 10·8 μl water/cm root.day and were up to five times higher than published inflows for winter wheat. At 30–100 cm sugar beet and winter wheat inflows were generally similar. The 0–30 and 30–120 cm layers contributed about 80 and 20% respectively of the total water use by sugar beet while no uptake was recorded below 110 cm. Previous studies have shown that sugar beet often takes up water from soil deeper than 110 cm, although it is not unknown for the depth of water removal to be restricted.
The effect of soil pH on the severity of Chocolate Spot infection on field bean varieties
Authors: Elliott Jennifer E. M. , Whittington W. J. 
Published: March 2009

SummaryField bean varieties were grown for 2 years on five plots varying in pH from 4·7 to 8·4. Non-aggressive Chocolate Spot infection was shown to be greater on plants grown in soil of pH 4·7 and 5·8 than on those grown in soil of pH 6·7, 7·7 and 8·4. Seed weight per plant was greater on soil pH 7·7 than on soil pH 4·7, suggesting that acid soil reduced plant vigour and consequently increased disease susceptibility. Varietal differences in infection were shown, although absolute resistance was not observed. Varieties differed in their susceptibility on soils of varying pH, and also showed different stability for susceptibility over the varying environmental conditions.
A drought experiment using mobile shelters: the effect of drought on barley yield, water use and nutrient uptake
Authors: Day W. , Legg B. J. , French B. K. , Johnston A. E. , Lawlor D. W. , Jeffers W. De C. 
Published: March 2009

SummaryAutomatic mobile shelters were used to keep rain off a barley crop in a drought experiment. The treatments ranged from no water during the growing season to regular weekly irrigation. This paper reports the effect of drought on the harvest yield and its components, on water use and nutrient uptake.Drought caused large decreases in yield, and affected each component of the grain yield. The magnitude of each component varied by up to 25% between treatments, and much of the variation could be accounted for by linear regression against the mean soil water deficit in one of three periods. For the number of grains per ear, the relevant period included tillering and ear formation; for the number of ears per unit ground area, the period included stem extension and tiller death; for grain mass, the period included grain filling.The harvest yields were linearly related to water use, with no indication of a critical period of drought sensitivity. The relation of grain yield to the maximum potential soil water deficit did show that a prolonged early drought had an exceptionally large effect on both yield and water use.Two unsheltered irrigation experiments, also on barley, were made in the same year on a nearby site. The effects of drought on yield in these experiments were in good agreement with the effects observed on the mobile shelter site.When fully irrigated, the small plots under the mobile shelters used water 11% faster than larger areas of crop, because of advection. The maximum depth from which water was extracted was unaffected by the drought treatment. When 50% of the available soil water had been used the uptake rate decreased, but the maximum depth of uptake continued to increase.Measurements of crop nutrients at harvest showed that nitrogen uptake was large, because of site history, and that phosphate uptake was decreased by drought to such an extent that phosphate shortage may have limited yield.
Gross energy yields and the support energy requirements for the production of sugar from beet and cane; a study of four production areas
Authors: Austin R. B. , Kingston G. , Longden P. C. , Donovan P. A. 
Published: March 2009

SummaryIn t h e four production areas studied the gross energy contents of the biomass of the U.K. and Californian sugar beet crops were about 222 GJ/ha/year, while those for the Queensland and Transvaal sugar cane crops were about 682 GJ/ha/year. Recoverable sucrose constituted about 45% of the gross energy yield in the sugar beet crops but only about 29% in t he sugar cane crops, largely due to the bagasse (fibre) present in the cane. Since the sugar cane bagasse was used as fuel it provided nearly all the energy for the production of raw sugar from the sugar cane crops, but sugar beet by-products supplied no energy for t he production of sugar from sugar beet. This difference between the two species was the main reason why the support energy required for sugar production from beet, 28·8 GJ/t sugar, was greater than for production from sugar cane, 10·5 GJ/t sugar. The ratios, energy in refined sucrose:support energy required for its production, were 0·60 for sugar beet and 1·60 for sugar cane.The efficiencies of conversion of the photosynthetically active solar radiation incident on the crops into energy in biomass (excluding fibrous roots) were 1·2% for sugar beet and 2·0% for sugar cane. This difference in efficiency did not appear to be due to a consistent species difference in the proportion of t he radiation intercepted by the crops, and may have been a consequence of the more efficient photosynthetic carbon fixation mechanism in sugar cane than in sugar beet. The efficiencies of conversion of incident photosynthetically active radiation into energy as sucrose recovered from the plants showed no consistent difference between species and averaged 0·56%.
Effects of some phenolic compounds and gibberellic acid on flowering and yield characters of cheena millet (Panicum miliaceum L.)
Authors: Datta K. S , Kumar Surinder , Nanda K. K. 
Published: March 2009

SummaryGibberellic acid (GA3); monophenols, salicylic acid (SA) and β-naphthol (β-N); diphenols, catechol (CT) and resorcinol (Res); and polyphenols, chlorogenic acid (CA) and tannic acid (TA) hastened the emergence of ears and increased the numbers of branches and ears, number of seeds, seed weight and the 1000-seed weight in cheena millet (Panicum miliaceum L.). The results show that the action of phenolic compounds is not related to their structural configuration as is considered by some workers.
Effects of sex and gonadectomy on the growth and development of Southdown × Romney cross lambs. Part II. Effects on Carcass grades, Measurements and chemical composition
Authors: Everitt G. C. , Jury K. E. 
Published: March 2009

The influence of sex and gonadectomy on carcass grades, measurements and chemical composition is reported from a comparative slaughter experiment involving 100 Romney x Southdown cross lambs.Grading results, although based on small numbers of carcasses, showed a tendency to down grade entire ram lamb carcasses.Linear carcass measurements indicated some differences in conformation between the four ‘sexes’, although these were somewhat inconsistent over the two slaughter ages at which measurements were recorded. Relatively larger eye muscle areas were evident for gonadectomized than for entire lambs and for males than for females. Fat cover over the eye muscle was lower for entire rams than for the other ‘sexes’.
Factors affecting production records of lambs from a flock of East African Blackheaded sheep
Authors: Trail J. C. M. , Sacker G. D. 
Published: March 2009

1. The effects of age of ewe, and year, sex and type of birth of lambs on lamb weights between birth and weaning were measured and appropriate correction factors estimated in a flock of East African Blackheaded sheep maintained over an 11-year period in Western Uganda. These correction factors were then used to examine the effects of a long dry season at different stages of lamb growth.2. On birth weights the effects of sex ranged from 0-25 lb. to 0-40 lb.; twinning 1-0 lb.; gimmer's lamb 0-5 lb. On 2-month weights the corresponding adjustments were 0-2 lb.-l-4 lb.; 5-1 lb.; 1-7 lb. On weaning weights 0-3 lb.-2-9 lb.; 6-0 lb.; 2-6 lb.3. A long dry season during late pregnancy did not appear to affect lamb birth-weights and a dry season between 2 months and 5 months of age did not affect lamb weaning weights. However a dry season during the main suckling period from birth to 2 months of age significantly lowered lamb weights at 2 months of age.
Studies on the cutting management of grass-clover swards. IV. The effects of close and lax cutting on the yield of herbage from swards cut at different frequencies
Authors: Reid D. 
Published: March 2009

1. The effects of cutting herbage to either 1 in. or 2½ in. from ground level were studied at varying cutting frequencies in two experiments on a perennial rye-grass/white-clover sward. In one of the experiments the frequency of cutting was decided by the stage of growth of the herbage, and in the other it was decided on a time basis where cutting was carried out at intervals of 2, 4 or 6 weeks throughout the growing season.2. Greater yields of herbage dry matter were obtained by cutting to 1 in. rather than to 2½ in. at all cutting frequencies in both experiments. This effect did not vary significantly with frequency of cutting where cutting dates were decided by the stage of growth of the herbage. However, where the cutting frequency was decided on a time basis, close cutting gave a relatively greater yield increase compared with lax cutting where the herbage was cut every 2 weeks instead of every 4 or 6 weeks.3. The results suggest that the practice of cutting at an average stage of growth in previous experiments probably had little or no influence on the effects recorded for the contrasting closeness of cutting treatments.
Sodium appetite and sodium metabolism in ruminants assessed by preference tests
Authors: Bell F. R. , Sly Jennifer 
Published: March 2009

SummaryAdult sheep, unweaned and mature weaned calves have been examined by metabolic studies for sodium balance. The ratio of sodium input/output was near unity with only a very small amount of the ingested sodium salt being retained. A positive sodium balance was always present, with excess sodium salt being excreted. The main channel of sodium excretion was the kidney, although when sodium intake was increased the sodium content of the faeces showed a proportional increase. Unweaned calves, a few days old, were quite able to excrete excess sodium salts in concentrated urine.There was a clear difference in preference for sodium salts over water, between weaned calves allowed access to sodium salts while being fed milk, and weaned calves denied sodium salts at the milk feeding stage. Sodium-naive calves showed a marked preference for sodium salt solutions while the sodium-experienced calves showed at best an indifference and sometimes even an aversion. With continued access to sodium salts the volume ingested declined steadily in both groups but food intake remained constant.In both calves and sheep the preference for sodium salts showed considerable variation between animals. The evidence from parallel metabolic studies suggests that this variation indicates that salt intake is controlled by some mechanism, possibly in the central nervous system, which is activated by dynamic sodium metabolism. Our experimental results confirm that ruminants have a well developed salt taste but predilection for sodium salts could be a biochemical manifestation rather than a hedonic propensity.
Compensation of oil-seed rape (Brassica napus L.) plants after damage to their buds and pods
Authors: Williams Ingrid H. , Free J. B. 
Published: March 2009

SummaryThe relationship has been investigated between the yield of oil-seed rape (Brassica napus L.) plants and (a) the proportion of podless stalks, (b) the proportion of pods infested by seed weevil larvae and (c) the effect of removing a proportion of buds and pods. Plants compensated for damage and, although late removal of buds or pods sometimes caused greater yield loss than early removal, only plants with more than 60% podless stalks or buds removed had diminished yields. The numbers of podless stalks per plant increased with plant size. Removal of 60 % of a plant's pods caused no yield loss; in the field a maximum infestation of only 25% of the plant's pods with seed weevil larvae occurred. The results are discussed in relation to damage by pollen beetles (Meligethes aeneus Fab.) and seed weevils (Ceutorhynch.ua ossimilis Payk.)
The effect of barley supplements on the voluntary intake and digestion of low quality roughages by sheep
Authors: Lamb C. S. , Eadie J. 
Published: March 2009

SummaryOat straw, timothy straw and two field-cured hays (43·8, 47·3, 52·0 and 56·0% organic matter digestibility (OMD) and 0·56, 0·75, 1·00 and 1·41% N respectively) were fed ad libitum together with 0, 235, 470 and 705 g D.M. of rolled barley to 5-year-old North Country Cheviot wethers in four 4x4 Latin square designs (Expt 1). In an attendant study (Expt 2) of conditions with in the rumen four rumen fistulated wethers were offered daily 0, 200, 400 and 600 g D.M. of rolled barley with ad libitum hay (54·3% OMD, 1·45% N), also following a Latin square design.The voluntary intake of two of the hays (54·3 and 56·0% OMD) decreased progressively as the barley increased. Intakes of the other roughages were slightly increased when the lowest amount of barley was fed. For each roughage total organic-matter intake and the OMD of the ration increased progressively with increasing amount of barley consumed. No associative effects of barley on the OMD of the roughages were demonstrated. The acid-detergent fibre (ADF) digestibility of diets comprising the highest amount of barley with the oat straw and the field-cured hay of lowest N content were significantly lower than that of the respective all-roughage feeds. In Expt 2 the intake of increasing amounts of barley significantly reduced rumen pH, the molar proportion of acetic acid and the disappearance of hay and hay ADF from terylene bags within the rumen, while volatile fatty acid concentration and the molar proportion of butyric acid increased.Multiple regressions were obtained relating the change in roughage intake to the amount of barley fed and the digestibility and chemical composition of the roughages. The equation with the least error, explaining 88% of the variation, was Y= 30·561 — 0·615C — 21·453N±3·69, where Y is the change in roughage intake as a percentage of the intake of roughage fed alone, Cis barley intake as g OM/W0·73 and N is the nitrogen content of the roughage.
The influence of abomasal supplements of zein and some amino acids on wool growth rate and plasma amino acids
Authors: Reis P. J. , Tunks D. A. 
Published: March 2009

SummaryMerino sheep were given abomasal infusions of (i) zein (80 g/day), (ii) zein (80 g/day) supplemented with L-lysine (6 g/day), L-tryptophan (1 g/day) or lysine and tryptophan together, or (iii) L-leucine (20 g/day). Effects on wool growth (length growth rate, fibre diameter, fibre volume growth rate and mass of wool grown) and on plasma amino acids were measured.Zein increased length growth rate and decreased fibre diameter; on average the volume growth rate and mass of wool grown were not significantly altered. The addition of tryptophan to the infusion of zein did not significantly alter wool growth, whereas the addition of lysine significantly increased all aspects of wool growth. The responses to these treatments were rapid and were adequately assessed during 12-day infusion periods. The infusion of leucine did not cause any appreciable changes in wool growth.Leucine supplementation increased the concentration of leucine in blood plasma about six-fold. Zein decreased the concentration of lysine and ornithine in plasma and increased the concentration of several essential amino acids; leucine was increased about seven-fold. The addition of tryptophan to zein had no effects on plasma amino acids, whereas lysine decreased the concentration of several amino acids in plasma and markedly increased lysine.
Studies on forage cell walls
Authors: Choung C. C. , McManus W. R. 
Published: March 2009

SummaryResults of a 13-week group feeding study (Expt 1) and a 16-day digestion and mineral, nitrogen and water balance study (Expt 2) in which alkali-treated rice hulls were fed to young Border-Leicester × Merino sheep of 24-kg body weight are reported.Five pelletized diets comprising a 1:1 mixture of ground lucerne and alkali-treated ground rice hulls (Expt 1) or these five diets supplemented with biuret plus one diet of 100% lucerne pellet (Expt 2) were examined.Sodium hydroxide at levels of 0, 2·5, 5, 10 and 15% (w/w) was applied to rice hulls for 12 h and neutralized with acid. Sheep fed the 5% NaOH treatment level or greater maintained or increased body weight: those fed the 0 and 2·5% level lost body weight. Daily food organic matter intakes were: 5% alkali, 1025 g, 0% alkali, 765 g; 100% lucerne, 1195 g.Organic matter digestibility was highest (52%) for the diet containing rice hulls treated at the 15% alkali level and this digestion coefficient was significantly greater (P < 0·05) than for the control diet (nil alkali) (42%) but not significantly greater than for diets with 2·5, 5 and 10% levels of alkali.It'is indicated that cell wall organic matter of rice hulls treated with 15% alkali was digested to an extent of 62% whereas cell wall organic matter in the control diet (0% alkali) was digested to an extent of 13%.Cellulose digestion (52%) of the rice hull component of diets was not increased by alkali treatment suggesting the alkali to have freed hemicellulose components of the cell wall for digestive attack. Digestibility of lignin of the rice hull component of diets was not significantly increased by alkali treatment.Animals tolerated the salt contents of diets containing rice hulls treated at high levels of alkali, were able to clear the excess salt from their bodies without significant alteration of their blood haematocrit ratios, and drank significantly more water. All sheep fed diets containing rice hulls had appreciable amounts of soluble silica in their blood plasma (> 100/μg/l) and urine (> 25 μg/l).It is concluded that alkali beneficiation of rice hulls offers a means of enhancing their nutrient worth to ruminants and that the process requires further study.
Suitability ofSpodoptera littoralislarvae for development ofMicroplitis rufiventris
Authors: Hegazi E. M. , El-Minshawy A. M. , Hammad S. M. 
Published: March 2009

SummaryA study of the solitary parasitoidMicroplitis rufiventrison larvae ofSpodoptera littoralisshowed that the age of the host at parasitization influenced the rate of development of the parasite, the percentage of parasitized hosts giving rise to mature parasite larvae, the number of moults subsequent to stinging, duration of larval instars, and the fecundity and longevity of the resulting adult parasites.
Effects of date of planting on growth and yield of contrasting potato varieties in Pembrokeshire
Authors: Allen E. J. 
Published: March 2009

SummaryFour experiments over 2 years which examined the effects of date of planting (from mid-March to early May) on the growth and yield of early, second early and maincrop potato varieties are described. In two experiments the seed used was physiologically old (heavily sprouted) and in the other two experiments relatively young seed (limited sprout development) was used. In the early variety, Home Guard, tuber yield at maturity was unaffected by delay in planting when physiologically old seed was used but increased leaf area and higher tuber yields resulted from later planting of younger seed. With both types of seed the maincrop varieties, Desirée and Maria Piper, produced larger leaf areas from later planting in one year but smaller leaf areas in the other year. In both years with both types of seed, tuber yields at the end of August were higher from the earlier plantings of these varieties. The physiologically young seed of Red Craig's Royal behaved in a similar manner to the maincrop varieties and the physiologically old seed behaved in a similar way to Home Guard.Any yield advantages of early varieties over maincrop varieties from any date of planting were small and short-lived and the physiological reasons for differences between varieties are discussed in the light of these results. It is suggested that the current classification of varieties is unjustified and that variety testing should take more account of the effects of physiological age.Tuber yields from the maincrop varieties were very high (60·80 t/ha) and this is attributed to the synchrony of leaf growth and increasing light receipts which may be readily achieved in the mild springs of W. Wales.
The feeding value of normal and brown midrib-3 maize silage
Authors: Weller R. F. , Phipps R. H. 
Published: March 2009

SUMMARYNormal and brown midrib-3 (bm3) maize silages were fed to sheep, lactating cows and dairy calves to determine the effect of the bm3 gene on in vivo digestibility, dry-matter intake and animal performance.In two trials wether sheep were fed either normal or bm3 maize silage at maintenance level. In the first experiment the bm3 gene significantly increased the digestibility of the organic matter(OM), cell wall constituents (CWC), acid-detergent fibre (ADF), cellulose and hemicellulose from 76·9, 74·7, 67·3, 74·2 and 79·5% to 79·6, 79·2, 75·8, 80·8 and 81·5%. In the second experiment the gene increased the digestibility of the OM, CWC, ADF and cellulose from 65·9, 44·7, 28·5 and 38·7% to 701, 59·3, 560 and 66·1, 39·1,32·8, 40·4 and 45·5% to 68·1, 51·9, 53·7, 58·0 and 49·2%. The digestibility of the protein was similar for both diets.In a feeding trial 6-month-old calves were fed either normal or bm3 silage ad libitum together with 1·6 kg D.M. of a protein supplement. The dry-matter intake of the two silages was similar; however, the daily live-weight gain of 0·92 kg for calves fed the bm3 diet was significantly higher than the 0·83 kg for calves fed the normal diet.