bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on selection for yield in wheat. An application of genotypic and phenotypic correlations, path-coefficient analysis and discriminant functions
Authors: Das P. K.
Published: March 2009

Grain yield in wheat, as in other crops, is a complex character, made up of many subcharacters. In the present investigation the study of genotypic and phenotypic correlations and path-coefficient analysis indicated that 250-grain wt. and ear number were two important component characters in wheat. Under these circumstances it would be desirable to select those plants which produce large number of tillers and very large and bold sized grains. The greater the number of tillers on a plant the greater would be the number of grains/plant. Again large and bold type of grain would obviously give higher seed wt.

With the use of discriminant functions it was observed that a maximum genetic gain of 7·44% was obtained when grain yield/plant, 250-grain wt., no. of ears/plant and ear length were included in the function. This would suggest that the discriminant function is superior to straight selection in wheat. However, an expected gain of 4·13% was realized when only 250-grain wt. and grain yield/plant were taken into account. In the present analysis it appeared that relatively more emphasis should be given to grain wt. during selection. To make proper use of such characters in selection, their importance must be considered in the definition of economic worth. Progress measured in terms of yield alone will be less when the economic importance of plant type is ignored.
Growth characters and yield of sorghum (Sorghum vulgare Pers.) as affected by contents of water–soluble P in triple superphosphate/dicalcium phosphate and triple superphosphate/rock phosphate mixtures
Authors: Govil B. P. , Prasad Rajendra
Published: March 2009

A field experiment was made during the rainy seasons of 1968 and 1969 on a sandy loam soil to study the response of Sorghum hybrid CSH–1 to phosphorus in relation to content of water-soluble phosphate in fertilizers. Triple superphosphate, dicalcium phosphate, rock phosphate (200-mesh), nitrophosphate and mixtures of triple superphosphate with dicalcium phosphate and rock phosphate in 3:1, 2:2 and 1:3 ratios were studied. The amounts of phosphorus applied were 30 and 60 kg P2O5/ha. Phosphorus application significantly affected dry matterproduced, plant height, days to 50% bloom, number of grains per ear, thousand-grain weight, stover and grain yield. Triple superphosphate and 3:1 triple superphosphate/dicalcium phosphate mixture were the most effective while rock phosphate and 1:3 triple superphosphate/rock phosphate mixture the least. Differences among sources were more marked in 1968 and at the higher amount i.e. 60 kg P2O5/ha. The response of sorghum to phosphorus was considerably lowered when the water solubility waa below 50% in triple superphosphate/dicalcium phosphate mixtures and below 75% in triple superphosphate/rock phosphate mixtures. Relative effectiveness was assessed by calculating ‘superphosphate equivalents’ and ‘multiple regressions’. Using superphosphate equivalents dicalcium phosphate, nitrophosphate and rock phosphates were 47–53%, 35–56% and 3–25%, respectively, as effective as triple superphosphate.
Breed and seasonal differences in quantities of lipids on skin surface and hair in cattle
Authors: Pan Y. S.
Published: March 2009

Differences between Sahiwals and Jerseys and between summer and winter in the quantities of lipids on the skin surface and on hair were studied.

Sahiwals had significantly greater quantities of lipids on both the skin surface and hair in summer and in winter. In both breeds, there were significantly greater amounts of lipids on the skin surface and on hair in winter. In both breeds a significantly greater quantity of lipids was present on hair than on skin in winter but not in summer.

Jerseys had greater weight of hair/unit area of skin than Sahiwals in both summer and winter. There was no significant correlation between the amount of lipids on hair and the weight of hair.
The relationship between exchangeable soil magnesium and response by sugar beet to magnesium sulphate
Authors: Draycott A. P. , Durrant M. J.
Published: March 2009

Fifty-three experiments made between 1959 and 1968 tested the response to magnesium sulphate by sugar beet on fields where magnesium deficiency symptoms were expected. Soil samples, taken before applying fertilizers, were analysed for exchangeable magnesium by four methods. Sodium, potassium and calcium in the soil extracts were also measured to determine whether they influenced response to magnesium.

Results of different methods of analysing soil for magnesium were related to each other and to the percentage yield-response to magnesium fertilizer. The concentration of other soil cations did not affect response to magnesium fertilizer, but giving other cations, especially sodium, as fertilizer decreased the concentration of magnesium in the crop. Nevertheless, even on fields deficient in magnesium, the largest yield was from plots given sodium and posassium fertilizer together with a dressing of magnesium.

Sugar beet grown on soils containing less than 20 p.p.m. Mg extracted with ammonium nitrate usually gave a profitable response to magnesium fertilizer. When soil magnesium was 20–35 p.p.m., yield of sugar beet on some fields was increased slightly. Plants in some experiments had poorly developed root systems and response to magnesium was then always larger than expected from soil analysis.
Harvesting sugar-beet seed
Authors: Longden P. C.
Published: March 2009

Comparisons of the effects of harvesting sugar-beet seed by the traditional method of tripodding with barn drying, swathing followed by threshing with a pick-up combine or desiccation with diquat followed by direct combine harvesting showed that there were no consistent or large effects on seed yield, germination, monogermity or size distribution. Thus the best method will be the one which is easiest and/or cheapest, which at present is swathing followed by pick-up combine threshing.

Sprays of NAA or 2,4,5-T at 10 or 100 mg a.i./l water before or after flowering had no effect on seed yield or germination and efforts to restrict the loss by shedding of large viable seed failed. Neither chemical decreased germination percentage by setting parthenocarpic seed. Attempts were made to dwarf the 2 m high seed crop to make it suitable for direct combine harvesting. Daminozide sprayed at 1000, 5000 or 10000 mg a.i./l water before or after the winter did not affect plant height, seed yield, germination, monogermity or size distribution. Chlormequat chloride applied similarly dwarfed plants by up to 18% but this was not enough to give a crop less than 1 m high suitable for direct combine harvesting. It did not affect seed yield, germination, monogermity or size distribution. Ethephon sprayed at 10, 100 or 1000 mg a.i./l water when plants were bolting had no detected effects. Chlorflurecolmethyl was sprayed at 10 or 100 before bolting or 1, 10 or 100 mg a.i./l water afterwards. Plants sprayed with the 100 mg/1 solution were dwarfed to less than 1 m high but the treatment was unsuccessful because it greatly reduced seed yield and germination; monogermity was not affected but a much greater proportion of seed fell into the small size grades.
Nitrogen retention from dietary urea by ewes in late pregnancy
Authors: Parkins J. J.
Published: March 2009

Three separate nitrogen balance experiments were made in three consecutive years. Comparisons of nitrogen retention were made between late-pregnant (15–20 weeks) Greyface (Border Leicester ♂χ Scottish Blackface ♀) ewes given a basal diet of hay and molassed sugar-beet pulp cubes (SBP, 1·25 em diameter x ca. 3cm length) and when given additional nitrogen supplied as urea contained in molassed sugar-beet pulp cubes (SBPU). Both sugar-beet pulp materials were adequately supplemented with minerals and vitamins. Supplementation with urea significantly increased nitrogen retention.
The effect of supplementation with protein, energy and L-methionine, on the digestion of silage by sheep
Authors: Gill Margaret , Ulyatt M. J.
Published: March 2009

Mature Romney wethers with rumen cannulae and re-entrant cannulae in the proximal duodenum were fed a basal diet of silage with supplements of formaldehydetreated casein (protein) and starch/sucrose (energy). In addition methionine availability was increased by infusion of L-methionine into the duodenum.

Maximum intake was limited to near-maintenance with the aim of comparing treatment effects at the same level of intake. In practice, intake of the control silage alone decreased markedly after 10 days of feeding. This decline was significantly (P &0·01) reduced on the protein and energy supplemented diets, and intake increased again during the period of methionine infusion.

Protein and energy supplementation increased the flow of total N (P < 0·01) into the duodenum on the control silage and the flow of amino acids into the duodenum was increased from 50 g/day on the basal diet, to 77 g/day on the energy-supplemented diet, and 111 g/day on the protein-supplemented diet.

The percentage of amino acid N in the total N entering the duodenum was also increased by supplementation: from 72% on the control to 81% with energy supplement and 94% with protein supplement.

Comparisons of the amino acid composition of duodenal digesta indicated that a substantial part of the increased duodenal protein flow on protein-supplemented silage was due to the formaldehyde-casein being protected from degradation within the rumen.

The flow of amino acids into the duodenum was found to be closely related to amino acid intake, such that 67% of the variation in duodenal amino acid flow was associated with variation in intake.
Effects of feeding diets containing Crotalaria retusa L. seed to growing pigs
Authors: Ross A. J.
Published: March 2009

Seeds of the plant Crotalaria retusa L., containing 4·4% of the pyrrolizidine alkaloid monocrotaline, were fed in a finely ground form to groups of four pigs from 6 weeks of age. Six levels, 0·004, 0·01, 0·02, 0·05, 0·10 and 0·50% by weight of seed in the diet, were fed continuously for up to 19 weeks. In addition a separate regime, designed to mirror an outbreak of poisoning at a local piggery, consisted of feeding 0·10% for 3 weeks followed by 0·05% for 1 week.

Exposure to more than 0·01%, whether fed continuously or not, resulted in reduced voluntary feed intake and live-weight gain, and high mortality. At 0·50% a reduction in feed conversion efficiency was also obvious. Levels of 0·004% and 0·01% had no significant effect on the production performance of the pigs.

The results of this trial suggest that no more than 0·01% ground C. retusa seed should be included in the diets of pigs. When 0·004%–0·01% is included care should be taken as the long-term effect of the subclinical disease produced is not known.
The effects of a granular nitrogen fertilizer and a foliar spray of urea on the yield and bread-making quality of ten winter wheats
Authors: Pushman Fiona M. , Bingham J.
Published: March 2009

Ten winter wheat varieties, representing a range of milling and bread-making quality were grown in a split-plot field trial with two levels of irrigation and three levels of nitrogen fertilizer. Grain yield was increased by irrigation and by fertilizer treatments. Application of 90 kg N/ha applied in granular form increased yield by 12.4 and 6.1% and grain protein by 13.0 and 33.7% for the irrigated and non-irrigated plots respectively. A further 45 kg N/ha applied as an aqueous foliar spray of urea (0.125 kg/1) at anthesis increased protein by 12.4% for the irrigated plots and by 8.8% for the non-irrigated plots with little effect on yield. The varieties differed significantly in yield and protein content, resulting in negative regressions of yield and protein content at each N treatment. The production of protein (weight N/unit area) was similar for all varieties, but flour extraction was reduced by the urea treatment. Varietal differences in flour extraction were stable and not correlated with either 1000-grain weight or test weight. Loaf volume was increased by the granular N fertilizer but not by the urea spray, despite the increase in flour protein and a decrease in flour α-amylase activity, indicating that applications of nitrogen after anthesis are likely to be later than the optimum for improving bread-making quality.
Serial designs balanced for effects of neighbours on both sides
Authors: Dyke G. V. , Shelley Christine F.
Published: March 2009

Designs for experiments that allow the independent estimation of the effects of treatments to neighbouring plots (units) on each side were constructed by use of an electronic computer. Their utility (e.g. in the study of air-borne disease of field crops) is indicated and methods of analysis are discussed.
Persistency of lactation in the Improved Valachian breed of sheep
Authors: Louda F. , Doney J. M.
Published: March 2009

The possibility of using sustained lactation as a maternal character for the enhancement of lamb growth has been suggested by Doney & Peart (1976). Horák & Jakubec (1964) shows that Improved Valachian ewes had a relatively sustained pattern of lactation when lambs were suckled. This breed was developed by cross-breeding between the Texel breed and the original Valachian, a coarsewoolled, mountain breed used to produce milk for cheese. The process of breed development has been described by Laurinčík (1964).
Chemical control of chocolate spot disease of field beans
Authors: Doto Severa A. , Whittington W. J.
Published: March 2009

The ability of two chemicals, Benlate and BAS352-04F, to control chocolate spot (Botrytis fabae) disease of field beans (Vicia faba) was examined in five small-plot or field experiments. The incidence of the fungus was never such as to reach the aggressive stage naturally, although severe infection was induced temporarily in certain experiments by enclosing the plots in plastic-covered boxes after inoculation with fungus. Increasing the recommended dose of BAS352-04F but not Benlate resulted in improved control and applying either chemical twice was preferable to a single application. Control by BAS352-04F was sometimes better than Benlate in the early days after infection whereas the reverse was true later. These results are in keeping with their roles as contact, and systemic and contact fungicides respectively. In these small experiments, with low levels of infection, the use of fungicides did not result in significant increases in yield or yield components.
Summer-growing components of a pasture system in a subtropical environment. 1. Pasture growth, carrying capacity and milk production
Authors: Murtagh G. J. , Kaiser A. G. , Huett D. O. , Hughes R. M.
Published: March 2009

The leaf growth, carrying capacity and dairy production of four summer-growing pastures were measured in a subtropical area of Australia. The growing season was subdivided into ten 4-week periods and the production was estimated for each period. Carrying capacities were determined by rotationally grazing four paddocks of each pasture over the 4-week period, and varying the stocking density so that a target weight of leaf material remained on the pasture at the conclusion of each grazing.

A non-limiting rate of nitrogen fertilizer increased total leaf production of kikuyu by 97% over a control treatment without nitrogen, but the response was not evenly distributed throughout the season. It fell to 50% during autumn when growth on the nitrogen-fertilized pastures was restricted following heavy defoliation during late summer. The use of the tropical legumes, siratro and glycine, in a mixed sward with kikuyu, did not increase leaf production over a kikuyu control pasture. The legumes grew poorly and this appeared to be due to the combined effects of their poor adaptability to the krasnozem soil, a high plant mortality especially during the first winter after sowing, the 4-week grazing interval and strong grass competition.

The carrying capacity of the nitrogen-fertilized pasture was 1·3–5·3 cows/ha at the beginning (September–October) and end (April–mid June) of the growing season, and increased to a peak of 7·4–9·7 cows/ha during February-mid March. Nitrogen fertilizer increased the carrying capacity by an average of 131% over that on a kikuyu pasture without nitrogen. The carrying capacities were similar on kikuyu and on a mixed carpet grass-kikuyu pasture, both without nitrogen, but were less on a tropical legume-kikuyu pasture which was grazed at a lighter grazing intensity during autumn to aid legume persistence.

Reflecting the experimental method of adjusting the stocking density according to the pasture available, differences in dairy production per cow were small relative to differences in the carrying capacity. Consequently seasonal variation in total dairy production/ha mirrored the carrying capacity. Nitrogen fertilizer increased the average production of 4% fat-corrected milk to 13·2 t/ha/40 weeks, an increase of 133% over the control without nitrogen.

The results illustrate the marked seasonal imbalance in growth and carrying capacity for a given pasture, and emphasize the need to use mixed feeding systems to provide a uniform level of nutrition for a fixed number of cows.
Some factors Influencing intercalving periods of imported and home-reared Holstein cattle in western Nigeria
Authors: Adeneye J. A. , Bamiduro T. A.
Published: March 2009

The average of 160 intercalving periods of 47 imported and 33 home–reared purebred Holsteins in western Nigeria during 1967–75 was 628( ± 45) days. The probable effects of seven variables including origin of cow, sex of calf, season of calving, age of cow at calving, parity, year of calving and calf birth weight were investigated through an intra-class linear regression model in which the first three factors were treated as qualitative and the last four as quantitative factors. Origin of cow, sex of calf and season of calving did not significantly affect calving interval. Effects of age at calving, parity, year of calving and calf birth weight were highly significant (P < 0·01) but individual effects adjusted for others were not quite significant. These four quantitative factors were, however, highly interrelated; simple correlations which varied between 0·33 and 0·86 were highly significant. Interactions between the two sets of factors were negligible.
Factors influencing the concentration of minerals and metabolites in the plasma of cattle
Authors: Wiener G. , Russell W. S. , Field A. C.
Published: March 2009

One hundred and seventy-seven female Ayrshire cattle from approximately 6 months to 6 years of age were sampled on one occasion to determine the concentrations in plasma of Cu, P, Ca, Mg, Na, K and glucose. Eighty-nine adults, either lactating or dry, were re-sampled 2 months later to estimate concentrations of ketone bodies and free fatty acids. The data were analysed to estimate the contributions of various factors to variation in the concentrations.

The combination of age and stage of pregnancy or lactation significantly affected variation in all the constituents although some of this variation was accounted for by milk yield. The concentrations of Cu, Mg, glucose and ketones were significantly affected by milk yield. The presence of ketone bodies in milk (recorded in relation to the first occasion of bleeding only) was associated with a significant increase in the plasma concentrations of Na and Mg and a significant decrease of K and Ca.

The herd comprised pairs of genetically related animals. However, the estimates of heritability had large standard errors and only those for P and Ca were significantly positive.
Early spring and late autumn response to applied nitrogen in four grasses
Authors: Wilman D.
Published: March 2009

The regrowth of Aberystwyth S. 23 perennial ryegrass, S. 24 perennial ryegrass, S. 59 red fescue and S. 170 tall fescue was studied in field swards, comparing four levels of applied nitrogen, for 8 weeks following a clearing cut. The clearing cuts were in mid-October, mid-February and mid-March in each of 3 years, different plots being used on each occasion.

Grass yield was more closely related to solar radiation receipt than to temperature. When radiation during the 3 or 4 weeks before a period of study was added to radiation during the 8-week period, to incorporate some allowance for temperature, the amount of additional yield per unit of additional radiation comparing the first spring period with the autumn period was about the same as that comparing the second with the first spring period. Where no N was applied, there was little or no increase in yield above ground level or above 4 cm from week 1 to about week 6 in the autumn and first spring period, whereas where N was applied yield increased steadily, though rather slowly, during those 5-week periods. Response to N, measured as kg dry matter above 4 cm/kg N applied, was about twice as great in the second as in the first spring period; on the other hand response to N measured as number of days saved in reaching a given yield was greater in the first than the second spring period. The positive effect of applied N on relative growth rate occurred mainly in the rather early stages of regrowth, which seems to be typical of any time of year.

Applied N increased the N and nitrate-N content of herbage and reduced the watersoluble carbohydrate content. Applied N increased the number of tillers and the proportion of yield above 4 cm. Yield below 4 cm was not much affected by N or by stage of regrowth. The ‘earliness’ in spring of S. 24, S. 59 and S. 170 compared with S. 23 was associated with greater height and a higher proportion of yield above 4 cm and not with higher above-ground yield. The ryegrasses responded more to N than the fescues in respect of yield above 4 cm and number of tillers. In 2 years in which the number of tillers was relatively low at the beginning of the spring periods of study, the number increased during those periods and there was a large positive effect of applied N, whereas, in a year in which the number was high initially, there was no increase during the periods of study and little response to N.
A comparison of the juvenilizing effect of six juvenile hormone-like activity compounds on EgyptianCulex pipiensL.
Authors: Kelada N. L. , Gaaboub I. A. , Rawash I. A.
Published: March 2009

Tests were made to determine the juvenilizing effects of TH6040, JH-25, Altosid, Altozar, ZR-777 and ZR-619 onCulex pipiensL. using the IC50value (dose to inhibit the emergence of 50% of adults) as a criterion. The descending order of activity was Altosid, TH6040, Altozar, ZR-777, JH-25 and ZR·619. Insignificant prolongations were recorded in the larval or pupal durations except in the case of TH6040 (Dimilin). The time lapse from larval treatment (early fourth instar) to adult emergence was prolonged by about 18·7% following treatment with 0·0001–0·1 μg/ml.

Juvenilizing effects of the tested compounds applied to the early fourth instar extended to the adult stage ofCulex pipiensL. and affected the duration of the first gonotrophic cycle. The concentrations of TH6040, JH-25, Altosid, Altozar, ZR-777 and ZR-619 tested caused prolongation of the time between emergence and first oviposition by about 20–50% (at 0·0001–0·1 μg/ml), 3–26% (at 0·001–5μg/ml), 0–15% (at 0·1 × 10-8–0·001 μg/ml), 3-–23% (at 0·1 × 10-8–0·001 μg/ml), 9–27% (at 0·1 × 10-7–0·01 μg/ml), and 11–32% (at 0·1 × 10-7–0·01 μg/ml), respectively.

The results obtained indicated that the sex ratio ofC.pipiensL. changed progressively in all treatments but with an inconsistent trend according to the concentration of each compound. This conclusion provides further evidence on the effect of juvenile hormone-like activity compounds on adults emerging from treated larvae. The numbers of females produced were increased by about 15–30%, 9–27%, 1–35%, 1–38%, 6–44% and 31–71% after treatment with 0·0001–0·1 μg TH6040, 0·001–5μg JH-25, 0·1x 10-8–0·001 μg Altosid, 0·1 x 10-8–0·001 μg Altozar, 0·1 x lO-7–O·Ol μg ZR-777 and 0·01 × 10-7–0·01 μg ZR-619‘sol;ml, respectively.
The act of rumination
Authors: Gordon John G.
Published: March 2009

1. A detailed analysis was made of the rumination behaviour of one caged sheep on four combinations of diet, ranging from 100% hay to 100% concentrate meal.

2. When hay was fed there was no relationship between the quantity of it ingested and the amount of rumination, which averaged 8 hr. daily. When concentrates were fed alone rumination time fell to 2½ hr. per day and much of this was ‘pseudorumination’.

3. Evidence is produced to show that the number of chews and not the time chewing is the accurate way of measuring rumination quantitatively. This particular sheep made an average of 39,000 rumination chews per day when hay was fed.

4. The duration of the intervals between boli was constant at 15% of total rumination time, but the rate of chewing varied from 83–99 chews per minute, being slower during the midnight to noon half of the 24 hr., when most rumination occurred.

5. Rumination periods last from under 1 min. up to about 2 hr.

6. Tiring during a rumination period was reflected by an increase in the intervals between boli but the number of chews per bolus remained unchanged.

7. The first bolus of each period of rumination was chewed less than those following. This sheep averaged fifteen periods of rumination per day, a daily total of 500 boli were regurgitated. There were 2500 chews per period and seventy-eight chews per bolus.
Observations on the role of nutrition in coat shedding in cattle
Authors: Yeates N. T. M.
Published: March 2009

The coat changes of an experimental group of four undernourished Shorthorn heifers have been compared with those of a control group of four well-fed heifers.

Low nutrition impeded seasonal shedding in three of the four experimental animals, and the hair which was retained into the summer months appeared lifeless and bleached. One animal's hair and shedding were normal, despite low nutrition.

Two animals of the control group also partially retained their hair in the summer, but it was of normal colour, good lustre, and vital appearance.

It is concluded that plane of nutrition influences shedding, though some individuals within a breed are less affected than others. Two distinct varieties of coat retention were observed: one was of nutritional origin, the other inherent. Possible explanations of the differences are suggested.
Some properties of thiaminases associated with cerebrocortical necrosis
Authors: Edwin E. E. , Jackman R. , Jones P.
Published: March 2009

Thiaminases from different sources exhibit varied responses to change in pH and to differing activators, cosubstrates and inhibitors. These properties are used in an attempt to characterize the extracellular thiaminases of 17 strains of Bacillus spp. isolated from the rumen contents of animals affected with cerebrocortical necrosis and to compare these with the endogenous thiaminase present in the rumen content of such animals and with other known thiaminase-producing bacteria. Statistical analysis of the results obtained using different activators classified the isolates into two main groups corresponding to the presence of thiaminase I or thiaminase II. The pH characteristics of the rumen content enzyme differed significantly from any of the bacterial isolates examined.
The effect of lactation on protein synthesis in ovine skeletal muscle
Authors: Bryant D. T. W. , Smith R. W.
Published: March 2009

Protein synthesis was measured in non-breeding sheep and in sheep at two stages of lactation by constant intravenous infusion of [3H] tyrosine. In early lactation plasma tyrosine flux was 50% higher than in non-breeding ewes and it remained somewhat higher in late lactation. Estimates of protein synthesis per day in the whole body showed similar changes.

In early lactation the weights of the longissimus dorsi and semitendinosus muscles were respectively 37 and 28% lower than those for non-breeding ewes, but both muscles regained weight in late lactation. There were corresponding changes in the total protein, total RNA and total lipid contents of both muscles.

The fractional rates of protein synthesis in the longissimus dorsi and the semitendinosus were between 2 and 3% per day, but it was higher in heart muscle. At both stages of lactation the synthesis rate in the longissimus dorsi was similar to that in nonbreeding ewes, but in the semitendinosus and in the heart synthesis rates were lower in lactating animals. In both skeletal muscles the total protein synthesized per day was lower in early lactation because their total protein contents were lower at this time. It is concluded that the maternal skeletal muscles may undergo a controlled depletion during lactation.
Investigation of the effect of copper status and therapy on fertility in beef suckler herds
Authors: Phillippo M. , Humphries W. R. , Lawrence C. B. , Price J.
Published: March 2009

A survey on 17 beef suckler herds in the north-east of Scotland showed that there was no relationship between herd serum copper concentration (range 0·16–0·92 μg/ml) measured within 1 month of mating and the conception rate of the herd calculated from the pattern of calving to that mating. Cows treated with 100 mg copper before mating, in trials on four farms with low copper status and involving 221 animals, did not have an improved conception rate compared with control animals on the same farm. Copperper sewould therefore not appear to be a major factor in determining the fertility of beef suckler herds.
Size and shape of sampling units for estimating incidence of sharp eyespot, Rhizoctonia cerealis, in plots of wheat
Authors: Gilligan C. A.
Published: March 2009

It has long been known that the size and shape of sampling units used to assess crop yield may have significant effects upon the precision of the estimates (Smith, 1938; Hudson, 1939) but little is known about the effects when estimating incidence of disease. Gilligan (1980) showed that estimates of the incidence (i.e. presence or absence of disease) of stem canker (Phomx, lingam, perfect state Lepto sphaeria maculans)of oil-seed rape were more precise when large square sampling units rather than long rectangular units of similar area or small square sampling units were used. Moreover, estimates derived from the frequently used method of sampling by removal of 25 stems, supposedly at random from each plot, were shown to be biased.
Nitrogenous manuring of grass-clover leys for conservation, with particular reference to ‘late’ top-dressing
Authors: Hood A. E. M.
Published: March 2009

Results are recorded of experiments over four years to study the effects of various rates of N fertilizer applied early (soon after each cut) and late (1 or 2 weeks before cutting) to grass-clover swards cut repeatedly for conservation.

N fertilizer proved essential for high yields of dry matter and protein per acre. It reduced the amount of clover, but it is clear that clovers are not as productive as grasses adequately manured, and that any N excreted by clovers into the soil is far from enough to enable associated grasses to make full growth.

The amount of N fertilizer applied proved more important than the time of its application. Early N gave higher yields of dry matter but rather lower percentages of crude protein in the herbage than late N dressings.

To increase yields substantially and at the same time to maintain the protein content of the herbage on a par with a grass-clover ley it seems necessary to apply a minimum of 4 cwt. ‘Nitro -Chalk’/acre as an early dressing before each cut. An additional 2 or 3 cwt. ‘Nitro-Chalk’/acre may be applied from one to two weeks before cutting if even higher crude protein values are required.
The effects of cutting on regrowth of perennial ryegrass selections exposed to drought conditions
Authors: Norris I. B. , Thomas H.
Published: March 2009

The effect of drought on the growth and subsequent recovery growth of containergrown perennial ryegrass plants was assessed in a glasshouse. Dry-matter production and percentage of water-soluble carbohydrates were measured, and non-destructive measurements of growth components (leaf extension, leaf appearance and tillering) were made.

Drought had an effect upon all the variables recorded. Selecting for improved recovery growth was considered to be of more economic importance than selecting for improved growth during drought and the implications of defoliation are discussed in relation to drought recovery.

It was concluded that subjecting pot-grown plants to drought was a useful technique when screening selections for response to drought.
Response of snake cucumber (Cucumis melovar. pubescens) to some plant regulators
Authors: El-Kholy E. , Hafez H.
Published: March 2009

Trials were conducted during the summer seasons (1978 and 1979) at the Faculty of Agriculture, Elminia University, to evaluate the effect of some growth regulators on sex expression, sex ratio and yield production of snake cucumber. The results obtained showed that both sex expression and ratio could be modified with plant regulator sprays even under the long and high temperature conditions of Elminia governorate. All plant regulators induced the formation of the first female flower at lower nodes compared with the control. There was significant suppression of male flowers in plants sprayed with plant regulators. All the treatments gave an increase in total yield and improved fruit characters.
The chemical composition of the straw and grain of some varieties of spring oats in relation to time of harvesting, nitrogen treatment and environment
Authors: Dent J. W.
Published: March 2009

1. Three contrasting varieties of spring oats were grown at six centres in England and Wales for three seasons, at two levels of manuring. They were harvested at two stages of ripeness, and both straw and grain were analysed for all treatments.

2. Varietal differences in composition between samples of straw grown under similar conditions and harvested at comparable stages of ripeness were negligible. In this respect there was no relationship between quality of straw and that of grain.

3. Differences in composition attributable to environment were very large. Crude protein content ranged from 1·9 to 7·6%, and crops grown under cool and wet conditions always yielded a better quality straw than those grown under the warmer and drier conditions in the south of England.

4. The chemical composition of oat straw changed very little between the early ‘binder-ripe’ stage and the fully ripe ‘combine’ stage, although physically it tended to become more brittle and less attractive in appearance. The grain also showed little change in composition between the two times of harvesting.

5. A spring dressing of 2 cwt. per acre of nitrochalk increased the protein content of the straw very considerably, but the response varied widely with conditions. The average increase at all centres over three years was 20%.

6. Under cool and moist conditions the composition of oat straw was comparable with that of meadow hay.
Lamb survival as affected by inbreeding and cross-breeding
Authors: Galal E. S. E. , Afifi E. A. , El-Kimary I. S. , Ahmad I. A. , Shawar A. F.
Published: March 2009

Data representing 1928 lambing records were analysed to study the effects of inbreeding and cross-breeding on lamb survival to the ages of 7, 30, 120 and 180 days. The sheep flock consisted of two native breeds, Barki (B) and Rahmani (R); and the imported Fleisch Merino (M) as well as the crosses M × B and M × MB. Analysis was made by fitting a least-squares linear model that included the main effects of year and season of birth, sex, age of dam, type of birth, inbreeding of the lamb (Fd) and the dam (Fd) and breed group and the interactions season × type of birth, season × Fo and season × breed group. Lambs were classified into six groups according to the magnitude of the inbreeding coefficient: F ≤ 0·05, 0·05 < F ≤S 0·10, 0·10 < F ≤ 0·15, 0·15 < F ≤ 0·20, 0·20 < F ≤ 0·25 and F > 0·25. The average inbreeding coefficient in the flock was 0·12 and 0·08 For the lambs and their dams, respectively.

Sex of lamb and age of dam had no significant effect on lamb survival at any age while single-born lambs had a higher (P < 0·01 or P < 0·05) survival than twins at all ages except 7 days. Inbreeding of the lambs showed significant effect at 7 and 120 days. Increase in inbreeding of the dams was associated with higher mortality at all ages but the trend was not significant.

Differences among breed groups were not significant at 7 and 30 days, but were highly significant at later ages. The contribution of breed group to the total variance in survival increased with age. Hybrid vigour was highly significant in both crosses at 120 and 180 days.
Copper, molybdenum and sulphur contents of oats and barley in relation to chronic copper poisoning in housed sheep
Authors: Todd J. R.
Published: March 2009

The copper, molybdenum, and total sulphur contents were estimated in 124 samples of oats and 67 samples of barley obtained from various parts of Northern Ireland. Copper contents were in the low-normal range, the average of all oat samples being 3–9 ppm and of barley samples 4–9 ppm, and the range 1–5 to 8–4 ppm covering all samples analysed. The corresponding averages for molybdenum were 0–25 ppm and 0–30 ppm, about 10% of the samples in each case containing less than 0–02 ppm. Sulphur contents (expressed as sulphate) ranged from 0–23 to 0–46 %. The low molybdenum contents are considered to be of significance in the copper metabolism of housed sheep.
A theoretical appraisal of the relative merits of 50 % hybrid and synthetic varieties of grasses
Authors: Wright A. J.
Published: March 2009

The expected merits of the semi-hybrid variety, produced by bulk interpollination of two populations (Foster, 1971a, 6, c), are examined in relation to those of the synthetic variety. With diploid inheritance, the mean expression of both types of variety is seen to be the same. Any postulated difference in productivity must depend not only on the preferential establishment and survival of a small fraction of the total population, but on the existence of a correlation between characters determining productivity and establishment. For two populations producing a heterotic hybrid, a correlation due to loose linkage or gene association without linkage may result in the superiority of the semi-hybrid, but tight linkage or pleiotropy are more likely to favour the synthetic variety. It is concluded that superiority of the semi-hybrid mode of varietal production can only be established by means of a direct comparison with its synthetic counterpart, and not solely by the demonstration of upper-parent heterosis for productivity.
Aspects of nitrogen utilization in Asiatic water buffalo and Zebu cattle
Authors: Moran J. B.
Published: March 2009

The results of 62 comparative digestibility and nitrogen balance trials of Asiatic water buffalo and Zebu cattle fed the same roughage or mixed diet were analysed to test for species differences in various nitrogen input-output relationships. The influence of dietary metabolizable energy content on the utilization of dietary or apparently digested nitrogen (ADN) was also investigated.

There was no difference between buffaloes and Zebus in their ability to digest dietary nitrogen. The true nitrogen digestibility was calculated to be 81% and the metabolic faecal nitrogen excretion to be 0·36 g N/lOOg dry-matter intake. The buffaloes had lower rates of excretion of urinary nitrogen per unit increase in ADN, and at the same intake of ADN (143 mg/kg live weight/day), they had the higher nitrogen balance: 58v.48 mg/kg live weight/day. Dietary metabolizable energy content did not affect the utilization of digested nitrogen.

Estimates of metabolic faecal nitrogen and endogenous urinary nitrogen excretions and of maintenance requirements for digested nitrogen were similar to those of tropical large ruminants reported by other workers. On low-quality (0·8% N) or medium-quality (1·6% N) diets, it was calculated that buffaloes would have nitrogen balances.
The salt tolerance ofRhizobiumstrains and lentil genotypes and the effect of salinity on aspects of symbiotic N-fixation
Authors: Rai R.
Published: March 2009

ThreeRhizobiumstrains and four lentil genotypes were more salt tolerant under different salt stress conditions. Saline-resistant strains were more antibiotic resistant and showed higher relative rates of oxidation of carbohydrate and tricarboxylic acid intermediates. Under salt stress, significant interactions between strains and genotypes resulted in a differential response of N2·fixation and glutamine synthetase activity.
Estimates of combining ability, reciprocal effects and heterosis for yield and yield components in a common bean diallel cross
Authors: Foolad M. R. , Bassiri A.
Published: March 2009

A diallel crossing system involving two Pinto and two Kidney common bean (Phaseolus vulgarisL.) cultivars was evaluated in the field. Pin toes were significantly different from the Kidneys in seed yield and numbers of pods and seeds per plant and 100·seed weight. All the traits showed statistical significance among crosses and in comparisons involving parentalv.cross means. Heterosis values were large and significant for yield, numbers of pods and seeds per plant, number of seeds per pod and number of days from planting to flowering. The ratio of general to specific combining ability mean squares was low for yield, numbers of pods and seeds per plant and high for 100·seed weight and number of days to flowering. Significant reciprocal effects were found for seed yield and number of seeds per plant, but this effect was completely absent for 100·seed weight.
Effect of mulches and antitranspirants on the grain yield of sorghum grown under limited irrigations on a deep vertisol
Authors: De R. , Bheemiah G. , Ramsheshiah K. , Rao Y. Yogeswara
Published: March 2009

Field experiments made for 2 years on a deep vertisol under semi-arid conditions showed that soil-surface evaporation control by mulching with rice straw or transpiration suppression by foliar application of kaolin or atrazine increased the yield of grain sorghum. These materials decreased soil moisture depletion and thus increased water-use efficiency. Application of one irrigation at the boot-leaf stage was beneficial. No additional advantage was noted with two irrigations, one given 45 days after seeding and the other at anthesis.
Weight, size and shape relationships and their uses in the study of graded yield data
Authors: Morris G. E. L. , Currah I. E.
Published: March 2009

For many horticultural crops the distribution of weight over size grades is of more importance than the total weight. This paper shows how simply determined features of interrelationships of the weight, size and shape of an individual in the crop can be combined to provide estimates of various aspects of the distribution of crop weight over size grades. The two relationships required are (i) the probability density function of the grading variable for the crop; (ii) a function relating the weight of an individual to the corresponding value of the grading variable.

The paper shows how each of these can be determined either from published data or by simple experiment. Examples using data on onions and carrots are given to illustrate this and also to show some of the more important practical applications of the methods. For example, they allow the results of grading with one set of size grades to be extrapolated to a different set of grades without recourse to further measurement or experimentation and this is illustrated using published data on carrots. Other possible uses are also discussed and outlined.
Studies on the cattle of Northern Rhodesia. II. The carcass characters of steers from normal veld grazing and supplemented with salt and protein
Authors: Walker C. A.
Published: March 2009

1. The effect upon the carcass characters of indigenous steers of supplementing veld grazing with two levels of salt with and without protein in the dry season has been investigated.

2. The feeding of 1 oz. of salt, found in part I (Walker, 1958) to speed up growth to a significant degree, was shown also to have speeded up maturity in carcass characters.

3. No benefit was obtained from adding a dry season protein supplement to the salt; the feeding of protein without salt produced only slight insignificant effects.

4. The addition of 2 oz. supplementary salt noted in part I as having an inhibitory effect on growth by comparison with the lower salt level has been shown to extend to the carcass characters.

5. Additional evidence has been found in the carcass characters to give further support to the suggestion that the tropical indigenous animal possesses the capacity for stopping growth during adverse nutritional conditions and continuing again afterwards.
Nodulation and nitrogen fixation in chickpea (Cicer arietinum L.) under salt stress
Authors: Balasubramanian V. , Sinha S. K.
Published: March 2009

The effects of salt stress on the growth, nodulation and N accumulation during the vegetative phase was studied in chickpea (Cicer arietinum). Growth and N accumulation were adversely affected by salinity. The larger control plants produced new nodules but the existing nodules on stressed plants grew larger than those of control plants. All plants had similar %N contents but the total plant N was less in stressed plants due to the reduced growth of these plants. Reduced plant vigour was the primary effect of salt stress and was mediated through processes other than symbiotic N fixation.
Effect of genotype and rainfall on yield and quality of forage barley and wheat varieties in a semi-arid region
Authors: Hadjichristodoulou A.
Published: March 2009

The effect of rainfall on dry-matter (D.M.) yield, D.M. content and crude protein (CP) content of eight barley and three wheat varieties was studied under semi-arid conditions in Cyprus for 5 years. The best variety was 628 barley, which gave the highest mean yields (6·7 and 0·69 t/ha of D.M. and CP respectively), showed the highest response to annual rainfall (33 g D.M./mm rainfall) and gave high yields in all environments, D.M. yield was not affected significantly by earliness but late varieties had higher D.M. and lower CP contents than early varieties. All varieties showed around average stability. Regression coefficients between D.M. yield and mean yield of varieties for all environments ranged from 0·81 to 1·14 and were not related to D.M. yield of varieties.

The fraction of the variation in D.M. yield explained by the variation in annual rainfall varied with variety from 25% to 67%. Multiple regression analysis using the annual rainfall and the rainfall 1 and 2 months before harvesting produced a slightly, but not significantly, higher correlation over the simple correlation between D.M. yield and annual rainfall. Varietal response to annual rainfall, as expressed by the regression coefficient between D.M. yield and annual rainfall, was positively related to D.M. yield (r = 0·84, P < 0·01).

The correlation coefficients between D.M. content and annual rainfall ranged from −0·46 to −0·92 while that of CP content and annual rainfall, though not significant in most cases, also tended to be negative.