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PubMed1976

Chromosome aberration yields in human lymphocytes induced by fractionated doses of x-radiation.

Unstimulated (G0) human peripheral blood lymphocytes were exposed at 37 degrees C to doses of 200 or 500 rad of X-rays delivered in two equal fractions. The dose fractions were separated by intervals of up to 7 h in the 200 rad study and up to 48 h for 500 rad. In both studies the mean levels of dicentrics and total unstable aberrations began to decline when fractions were delivered with intervals of greater than 2 h. With 200 rad the yield had decreased to an additive baseline (i.e. equal to only twice the yield of a single 100-rad fraction) by an interval of 4 h. Following 500 rad the yield declined until 8 h and then remained 20% above the additive baseline even when 48 h separated the fractions. Possible explanations for this discrepancy are discussed. In a second experiment PHA stimulated lymphocyte cultures were exposed to 2 doses of 125 rad of X-rays up to 7 h apart in an attempt to demonstrate the late peak in aberration yields originally reported by Lane [5]. Control cultures received unsplit doses of 250 rad at the time of the corresponding second 125-rad fraction. No evidence of a late peak in dicentric yield was observed. The yield remained approximately the same irrespective of the time interval between fractions but these split dose yields were significantly different from the accompanying unsplit controls.

Chromosome Aberrations↗
PubMed1991

Nicotine yield as determinant of smoke exposure indicators and puffing behavior.

Relationships between machine smoking nicotine yield and different smoke exposure indicators were investigated in a cross-sectional study. For each of the four yield classes H (1.0-1.2 mg), M (0.7-0.9 mg), L (0.4-0.6 mg) and U (0.1-0.3 mg) 18 male and 18 female subjects were recruited. The experimental design (2 x 2) included smoking with lip contact or with a flowmeter holder, natural smoking of one cigarette or forced smoking (30 puffs). The analysis of presmoking measures revealed for plasma nicotine H greater than L, U; M greater than U, for plasma cotinine H, M greater than U, and no differences for respiratory CO. Pre- to postsmoking boosts of CO and nicotine increased with yield, but the differences were smaller than those in yield. This partial compensation can be attributed to puffing behavior as revealed by the differences between yield classes with respect to flowmeter measures (puff volume, flow parameters, number of puffs). Contact condition hardly influenced the results. Forced puffing revealed down regulation mechanisms in smoke absorption and, less pronounced, in puffing behavior. Cardiovascular and subjective effects were widely independent of yield. Plasma cotinine appeared as the best smoke exposure indicator, due both to its high retest reliability and its relationship to nicotine yield.

Adult↗
PubMed1989

Yields of field-grown soybeans exposed to simulated acidic deposition.

Rainfall acidity response functions for crop yield and growth are necessary to predict the overall impacts on crop yields of ambient and/or anticipated levels of acidic rain. The experiment described herein was performed at Brookhaven National Laboratory during 1984 and 1985 to determine the effects of simulated rainfalls of pH 5.6, 4.4, 4.1 and 3.3 on seed yields of four cultivars of field-grown soybeans (Glycine max Merrill). Soybeans were chosen because previous results suggested that certain varieties of this crop are sensitive to rainfall acidity and because they are an economically important crop in the USA. Sixteen plots per treatment were used. Plants were grown using standard agronomic practices under automatically movable exclusion shelters which minimize changes in the plant's microclimate. Analysis of variance of seed yields of the four cultivars showed significant treatments for all four cultivars. For all cultivars, seed yields were lower when exposed to simulated rainfalls of pH 4.4, 4.1 and 3.3 compared with rainfalls of pH 5.6. Compared with pH 5.6 rainfall (controls), yields of Amsoy exposed to pH 4.4, 4.1 and 3.3 were lower by 13, 11 and 12%, respectively. The percentage yield reductions for Asgrow, Corsoy and Hobbit were not as great as those of Amsoy. Averaged over all cultivars tested, there was a 9% seed reduction for plants exposed to simulated rain at pH 4.1 (comparable to ambient) compared with pH 5.6.

Journal Article↗
PubMed1990

Yield responses of different crop species to long-term fumigation with sulphur dioxide in open-top chambers.

Potted plants of commercial cultivars of rape (Brassica napus L., cv. 'callypso'), summer barley (Hordeum vulgare L., cvs. 'arena' and 'hockey') and bush beans (Phaseolus vulgaris L., cvs. 'rintintin' and 'rosisty') were continuously exposed in open-top chambers to sulphur dioxide (SO(2)) for the whole growing season in order to assess effects of this pollutant on growth and various yield parameters. Treatments consisted of charcoal-filtered air (CF) and CF supplemented with four levels of SO(2), resulting in mean exposure concentrations (microg m(-3)) of approximately 8, 50, 90, 140 and 190. With the exception of the 1000 seeds weight, which was slightly reduced, dry matter production and yield parameters of rape remained unaffected by all SO(2) concentrations or were even stimulated. Compared to CF vegetative growth of both bean cultivars was reduced by 10-26% at all SO(2) levels; however, with significant effects only for cv. 'rintintin'. While all SO(2) additions reduced significantly the yield (dry weight of pods) of the bean cultivar 'rosisty' between 17% and 32%, cv. 'rintintin' showed a significant reduction of up to 42% only at the two highest pollutant concentrations. Dry matter production of the barley cultivars was mainly impaired at SO(2) concentrations > 100 microg m(-3) with a reduction of 30-52%. While nearly all yield parameters of cv. 'hockey' reacted similar to the dry matter production, the yield of cv. 'arena' was reduced already at the low SO(2) levels. At a treatment concentration of 90 microg SO(2) m(-3) a significant yield loss of 30% was recorded. A reduction of the 1000 grains weight mainly contributed to these yield losses observed for both barley cultivars. From these results, it may be assumed that SO(2) concentrations within the range 50-90 microg m(-3) are potentially phytotoxic to some crop species.

Journal Article↗
PubMed1985

Analytical cigarette yields as predictors of smoke bioavailability.

The smoke intake of 865 undisturbed smokers of over 10 cigarettes per day was measured using plasma nicotine and cotinine, and expired carbon monoxide (CO) as markers. While nicotine yields, according to Federal Trade Commission (FTC) analytical standards, varied 16-fold from 0.1 to 1.6 mg/cigarette, the corresponding plasma nicotine values varied from around 25 to 45 ng/ml, and estimated mean nicotine intake of smokers varied from around 0.75 to 1.25 mg/cigarette. Expired CO and plasma cotinine values also varied in similar proportion, but mean daily cigarette consumption was independent of the FTC nicotine yield of the cigarettes smoked. The results indicate that pharmacodynamic satiation causes behavioral regulation, and that smokers of very high yield brands compensate downward, and vice versa. The ratio of tar yield to nicotine yield usually increases with increasing tar yield; therefore tar intake is likely to increase at higher tar yields, even though the increment of nicotine intake is small. It follows that FTC analytical determinations are poor predictors of relative intake of nicotine, CO, or tar, while rankings based on mean tar-to-nicotine ratio of a brand's smoke could be more meaningful. Moreover, the considerable variation of individual smoking behavior suggests that precise numerical rankings of cigarettes are not justified. An analogic ranking of cigarettes into a few broad classes would better reflect the realities and expectations of average consumers.

Adult↗
PubMed2004

Comparative effectiveness of cattle manure, poultry manure, phosphocompost and fertilizer-NPK on three cropping systems in vertisols of semi-arid tropics. I. Crop yields and system performance.

A field experiment was conducted on deep vertisols of Bhopal, India to evaluate the manural potential of three organic manures: farmyard manure (FYM), poultry manure (PM), phosphocompost (PC) vis-a-vis 0%, 75% and 100% recommended dose of fertilizer-NPK and to find out the most productive cropping system at various combinations of organic manures and chemical fertilizers. The seed yield of intercrop soybean (population converted to 100%) was 8.7% less than sole soybean whereas the grain yield of intercrop sorghum was 9.5% more than that of sole sorghum. However, the productivity in terms of soybean equivalent yield (SEY) was relatively high in intercropping system. The increasing NPK dose from 0% to 100% significantly improved SEY in sole sorghum and soybean/sorghum intercropping system and the integrated use of organics and inorganics recorded significantly more SEY than inorganics. The effect of nutrient management followed the order; 75% NPK + 5 t FYM ha(-1) > 75% NPK + 1.5 t PM ha(-1) > 75% NPK + 5 t PC ha(-1) > 100% NPK. Sorghum, both as sole and intercrop, responded more to PM while soybean to FYM. Application of 75% NPK in combination with PM or FYM or PC to preceding rainy season crops (soybean and sorghum) and 75% NPK to wheat produced significantly higher grain yield of wheat than those in inorganics and control indicating noticeable residual effect on the succeeding wheat crop and saving of 25% fertilizer-NPK. The effect of PC on rainy season crops was not as prominent as those of FYM and PM, but its residual effect on grain yield of wheat was comparable to those two organic manures. Among the cropping systems, soybean as preceding crop recorded the highest seed yield of wheat and was on a par with that of soybean/sorghum intercropping system. The yield of wheat following sorghum was the lowest. The total system productivity (TSP) was the highest in sorghum + soybean-wheat system and the lowest in the soybean-wheat system.

Agriculture↗
PubMed2005

Manganese and other micronutrient additions to improve yield of Agaricus bisporus.

Previous experiments have demonstrated that significant increases in yield of Agaricus bisporus mushrooms were achieved by adding a micronutrient rich fertilizer, Micromax, to the compost. This study was performed to determine the mineral(s) that are responsible for this yield improvement. An initial experiment determined that manganese was the mineral of primary importance; addition of 184 mg kg-1 Mn increased yield by 10.8%, compared to the control. Subsequent experiments demonstrated that the addition of manganese to the compost has a stimulatory effect on mushroom yields. Significant yield increases, ranging from 9.6% to 11.8% (compared to the control), were observed as a result of manganese additions varying between 50 and 300 mg kg-1. Also, data from the last set of experiments indicated that Micromax additions always resulted in greater yields indicating that micronutrients in Micromax, in addition to manganese, may be responsible for increasing yields.

Agaricus↗
PubMed2005

Effects of integrated use of organic and inorganic nutrient sources with effective microorganisms (EM) on seed cotton yield in Pakistan.

A field experiment was conducted to determine the effects of integrated use of organic and inorganic nutrient sources with effective microorganisms on growth and yield of cotton. Treatments included: control; organic materials (OM); effective microorganisms (EM); OM+EM; mineral NPK (170:85:60 kg); 1/2 mineral NPK+EM; 1/2 mineral NPK+OM+EM and mineral NPK+OM+EM. OM and EM alone did not increase the yield and yield attributing components significantly but integrated use of both resulted in a 44% increase over control. Application of NPK in combination with OM and EM resulted in the highest seed cotton yield (2470 kg ha-1). Integrated use of OM+EM with 1/2 mineral NPK yielded 2091 kg ha-1, similar to the yield (2165 kg ha-1) obtained from full recommended NPK, indicating that this combination can substitute for 85 kg N ha-1. Combination of both N sources with EM also increased the concentrations of NPK in plants. Economic analysis suggested the use of 1/2 mineral NPK with EM+OM saves the mineral N fertilizer by almost 50% compared to a system with only mineral NPK application. This study indicated that application of EM increased the efficiency of both organic and mineral nutrient sources but alone was ineffective in increasing yield.

Agriculture↗
PubMed2005

Effects of process variables on the powder yield of spray-dried trehalose on a laboratory spray-dryer.

A systematic examination is presented of the effects of process variables on the powder yield of amorphous trehalose obtained from the Buchi Model 191 laboratory-scale mini spray dryer. By using a specially made, narrow cyclone the powder yield could be greatly improved at all process temperatures examined. Calculations of the separation efficiencies of the improved cyclone and the manufacturer's standard cyclone are given, which show that the former's higher tangential particle velocity at the radius of the exit duct is responsible for the improved performance. The powder yield increases with higher process temperatures, owing to improved droplet drying and reduced droplet/particle deposition on the walls of the drying chamber. A maximum in the powder yield is reached, however, after which it decreases sharply. This is caused by heating of the cyclone wall to >10 degrees C above the so-called 'sticky point' of the trehalose, causing increased particle deposits on the walls of the tower and cyclone. Increasing liquid feed flow rate or decreasing atomizing air flow rate too extensively were both detrimental to powder yield. The drying air flow rate should be as high as possible to ensure sufficient enthalpy throughput to dry the trehalose adequately to give a high powder yield. The enthalpy balance calculation for drying trehalose with the new cyclone was used successfully to interpret the results obtained. Some recommendations for optimizing powder yield of an amorphous material are given.

Powders↗
PubMed2006

Gas/particle partitioning and yield levels of polycyclic aromatic hydrocarbons and n-alkanes in the mainstream cigarette smoke of commercial cigarette brands.

The gas/particle partitioning of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes was investigated in the mainstream smoke (MSS) from 59 commercial cigarette brands classified according to the existence of filter tip, the tar yield indicated on the packet, and the cigarette length and diameter, into 15 cigarette classes: non filter (NF), high (H), medium (M), light (L), super light (SL), ultra light (UL), one-tar yield (O), 100-mm long (H-100, L-100, SL-100, UL-100, O-100), and slim (SL-SLIM, UL-SLIM, O-SLIM). The gas/particle partitioning constant, Kp, was determined and its relationship with the subcooled liquid vapour pressure pL degrees of individual compounds was investigated. A good linear relationship was obtained for both chemical classes following the equation log Kp=mr log pL degrees+br. In all cigarette classes, PAHs were found to sorb more strongly on MSS particles than n-alkanes. Carcinogenic PAHs were detectable only in the total particulate matter (TPM) of MSS and their yields increased linearly with the TPM yield. However, when normalized against TPM, the yields of carcinogenic PAHs were quite similar in all cigarette classes with a slight drop from low tar- to high tar-yield brands suggesting probably lower biological activity per mg TPM for the latter. The nicotine-normalized PAH yields were also similar among the different cigarette classes suggesting that, if smokers adjust their smoking behavior to achieve a consistent nicotine intake, they will be exposed to an equivalent amount of carcinogenic PAHs regardless of whether they smoke full-flavored, light, or ultralight varieties.

Alkanes↗
PubMed2004

Mechanisms of uniformity of yield strains for trabecular bone.

Variations in yield strains for trabecular bone within a specific anatomic site are only a small fraction of the substantial variations that exist for elastic modulus and strength, and yet the source of this uniformity is not known. Our goal was to investigate the underlying mechanisms by using high-resolution, materially nonlinear finite element models of 12 human femoral neck trabecular bone specimens. The finite element models, used to obtain apparent yield strains in both tension and compression, assumed that the tissue-level yield strains were the same across all specimens. Comparison of the model predictions with the experimental data therefore enabled us to isolate the combined roles of volume fraction and architecture from the role of tissue material properties. Results indicated that, for both tensile and compressive loading, natural variations in volume fraction and architecture produced a negligible coefficient of variation (less than 3%) in apparent yield strains. Analysis of tissue-level strains showed that while bending of individual trabeculae played only a minor role in the apparent elastic behavior, the combined effects of this bending and tissue-level strength asymmetry produced apparent-level failure strains in compression that were 14% lower than those at the tissue level. By contrast, tissue and apparent-level yield strains were equivalent for tensile loading. We conclude that the uniformity of apparent yield strains is primarily the result of the highly oriented architecture that minimizes bending. Most of the variation that does occur is the result of the non-uniformity of the tissue-level yield strains.

Aged↗
PubMed2004

Growth promotion and yield enhancement of peanut (Arachis hypogaea L.) by application of plant growth-promoting rhizobacteria.

Although plant growth-promoting rhizobacteria (PGPR) have been reported to influence plant growth, yield and nutrient uptake by an array of mechanisms, the specific traits by which PGPR promote plant growth, yield and nutrient uptake were limited to the expression of one or more of the traits expressed at a given environment of plant-microbe interaction. We selected nine different isolates of PGPR from a pool of 233 rhizobacterial isolates obtained from the peanut rhizosphere on the basis of ACC-deaminase activity. The nine isolates were selected, initially, on the basis of germinating seed bioassay in which the root length of the seedling was enhanced significantly over the untreated control. All the nine isolates were identified as Pseudomonas spp. Four of these isolates, viz. PGPR1, PGPR2, PGPR4 and PGPR7 (all fluorescent pseudomonads), were the best in producing siderophore and indole acetic acid (IAA). In addition to IAA and siderophore-producing attributes, Pseudomonas fluorescens PGPR1 also possessed the characters like tri-calcium phosphate solubilization, ammonification and inhibited Aspergillus niger and A. flavus in vitro. P. fluorescens PGPR2 differed from PGPR1 in the sense that it did not show ammonification. In addition to the traits exhibited by PGPR1, PGPR4 showed strong in vitro inhibition to Sclerotium rolfsii. The performances of these selected plant growth-promoting rhizobacterial isolates were repeatedly evaluated for 3 years in pot and field trials. Seed inoculation of these three isolates, viz. PGPR1, PGPR2 and PGPR4, resulted in a significantly higher pod yield than the control, in pots, during rainy and post-rainy seasons. The contents of nitrogen and phosphorus in soil, shoot and kernel were also enhanced significantly in treatments inoculated with these rhizobacterial isolates in pots during both the seasons. In the field trials, however, there was wide variation in the performance of the PGPR isolates in enhancing the growth and yield of peanut in different years. Plant growth-promoting fluorescent pseudomonad isolates, viz. PGPR1, PGPR2 and PGPR4, significantly enhanced pod yield (23-26%, 24-28% and 18-24%, respectively), haulm yield and nodule dry weight over the control in 3 years. Other attributes like root length, pod number, 100-kernel mass, shelling out-turn and nodule number were also enhanced. Seed bacterization with plant growth-promoting P. fluorescens isolates, viz. PGPR1, PGPR2 and PGPR4, suppressed the soil-borne fungal diseases like collar rot of peanut caused by A. niger and PGPR4 also suppressed stem rot caused by S. rolfsii. Studies on the growth patterns of PGPR isolates utilizing the seed leachate as the sole source of C and N indicated that PGPR4 isolate was the best in utilizing the seed leachate of peanut, cultivar JL24. Studies on the rhizosphere competence of the PGPR isolates, evaluated on the basis of spontaneous rifampicin resistance, indicated that PGPR7 was the best rhizoplane colonizer and PGPR1 was the best rhizosphere colonizer. Although the presence of growth-promoting traits in vitro does not guarantee that an isolate will be plant growth promoting in nature, results suggested that besides ACC-deaminase activity of the PGPR isolates, expression of one or more of the traits like suppression of phytopathogens, solubilization of tri-calcium phosphate, production of siderophore and/or nodulation promotion might have contributed to the enhancement of growth, yield and nutrient uptake of peanut.

Arachis↗
PubMed2004

Ginseng reduces the micronuclei yield in lymphocytes after irradiation.

To assess the effect of Chinese ginseng in modifying the radiation-induced micronuclei (MN) yield in human G(o) peripheral blood lymphocytes (PBL), we conducted the cytokinesis-blocked (CB) MN assay in blood samples obtained from healthy volunteers (n=4). Before (137)Cs ex vivo irradiation, mononuclear cell cultures from each sample were incubated 24 h with different concentrations (0-2000 microg ml(-1)) of crude water extract of ginseng dry root. We found that (1) at 0 Gy and without the presence of ginseng, MN yield (mean+/-S.E.M.) was 11.7+/-2.7 per 1000 binucleated (BN) cells. Different concentrations of ginseng crude water extract did not affect the MN yields and the proliferative activity of PBL; (2) after 1 and 2 Gy exposure, radiation alone sharply increased the MN yields, respectively, to 119.6+/-17.4 and 340.5+/-20.9 per 1000 BN cells. However, treatment with ginseng for 24 h before radiation exposure, resulted in a significant linear decline of MN yields as ginseng concentration increases. Compared to radiation alone, the extent to which ginseng water extract reduced the MN yields induced by 1 Gy exposure was 46.0% at 1500 microg ml(-1) and 61.5% at 2000 microg ml(-1), and with 2 Gy exposure, it was 38.6% at 1500 microg ml(-1) and 46.5% at 2000 microg ml(-1); (3) MN data suggested a tendency for overdispersion relative to the Poisson model; and (4) over the different levels of ginseng concentrations, the trend in micronucleated BN index was as similar as that of the MN yields. These results indicated that (1) ginseng crude water extract exerts no apparent cytogentic effect on human PBL at concentrations up to 2000 microg ml(-1) as evaluated by the CBMN assay; and (2) the protection of ginseng water extract against (137)Cs-induced MN in human PBL is concentration-dependence. Therefore, our findings indicated that ginseng may have therapeutic value as a possible radioprotector for normal tissue during radiotherapy of cancer patients.

Adult↗
PubMed2004

Crop transformation and the challenge to increase yield potential.

Molecular transformation is commonly offered as a hope to overcome the apparent stagnation in crop yield potential. A basic understanding of the resource limits imposed on crops and the yield hierarchy going from gene expression to harvestable yield leads to a rather negative view that transformations of a few, or even of a complex of genes will result directly in major yield increases. Forty years of biochemical and physiological research illustrate the great difficulty in translating research at the basic level into improvements in crop yield. However, there are a few cases where physiological research has led to improved crop cultivars with increased yield. These successes are instructive in highlighting key elements required to achieve success in developing crop cultivars for increased yield.

Agriculture↗
PubMed2004

Comparison of the elastic and yield properties of human femoral trabecular and cortical bone tissue.

The ability to determine trabecular bone tissue elastic and failure properties has biological and clinical importance. To date, trabecular tissue yield strains remain unknown due to experimental difficulties, and elastic moduli studies have reported controversial results. We hypothesized that the elastic and tensile and compressive yield properties of trabecular tissue are similar to those of cortical tissue. Effective tissue modulus and yield strains were calibrated for cadaveric human femoral neck specimens taken from 11 donors, using a combination of apparent-level mechanical testing and specimen-specific, high-resolution, nonlinear finite element modeling. The trabecular tissue properties were then compared to measured elastic modulus and tensile yield strain of human femoral diaphyseal cortical bone specimens obtained from a similar cohort of 34 donors. Cortical tissue properties were obtained by statistically eliminating the effects of vascular porosity. Results indicated that mean elastic modulus was 10% lower (p<0.05) for the trabecular tissue (18.0+/-2.8 GPa) than for the cortical tissue (19.9+/-1.8 GPa), and the 0.2% offset tensile yield strain was 15% lower for the trabecular tissue (0.62+/-0.04% vs. 0.73+/-0.05%, p<0.001). The tensile-compressive yield strength asymmetry for the trabecular tissue, 0.62 on average, was similar to values reported in the literature for cortical bone. We conclude that while the elastic modulus and yield strains for trabecular tissue are just slightly lower than those of cortical tissue, because of the cumulative effect of these differences, tissue strength is about 25% greater for cortical bone.

Aged↗
PubMedDate not supplied

Hemoglobin and platelet count effect on platelet yields in plateletpheresis.

BACKGROUND: Platelet transfusion in thrombocytopenic patients, especially those with marrow failure, remains one of the most important support measures available. Treatment success depends on rational use of platelet transfusion. Platelet yield, reflected in transfused platelet dose, influences platelet recovery in the patient and allows prolonging intervals between transfusions. In this study, our main objective was to identify donor laboratory and clinical factors that showed some influence on platelet yield obtained by apheresis. METHODS: Healthy donor laboratory and clinical data were analyzed prior to performing plateletpheresis. Platelet yield was quantified after plateletpheresis procedure was concluded in two different ways: a) prefixed volume of 5,000 mL processed, and b) volume determined according to manufacturer recommendations. Age, gender, hemoglobin concentration, platelet and leukocyte count, height, and weight were included as yield-predicting donor variables. RESULTS: In group A, two variables were significant: donor platelet count and hemoglobin (Hb) concentrations with r = 0.554, and in group B, donor platelet count, Hb concentrations, and volume with r = 0.758. CONCLUSIONS: Donor platelet count and hemoglobin concentrations influence platelet yield: higher platelet count corresponds to higher yield, while hemoglobin shows an inverse relationship, i.e., the lower the hemoglobin concentrations, the higher the platelet yield.

Adolescent↗
PubMed2001

Growth and yield responses of spring wheat (Triticum aestivum L. cv. Minaret) to elevated CO2 and water limitation.

Spring wheat (Triticum aestivum L. cv. Minaret) was grown at two different CO2 concentrations (367 and 650 micromol mol(-1)) in open-top-chambers from sowing until final harvest. Furthermore two different watering treatments (well watered and water stressed) and two soil types of different fertility were used. At final harvest, which took place at growth stage 92, plants were separated into different fractions. Elevated atmospheric CO2 caused an accelerated chlorophyll-a breakdown and increased growth and yield. Total shoot biomass was enhanced by 43%, grain yield by 46% and main stem yield by 19%. Water stress also accelerated chlorophyll-a breakdown but reduced total shoot biomass by 40%, grain yield by 45%, main stem yield by 30% and thousand grain weight by 6%. On average, soil fertility altered shoot biomass by 30%, grain yield by 39% and main stem yield by 25%.

Biomass↗
PubMed2001

Factors affecting follicular population, oocyte yield and quality in camels (Camelus dromedarius) ovary with special reference to maturation time in vitro.

Three experiments were conducted to study a series of factors affecting in vitro reproductive parameters in camels. In Experiment 1, the effect of season and presence of a corpus luteum (CL) on ovarian follicular populations, oocyte yield and quality was studied using a total of 252 and 208 ovaries collected during the breeding and non-breeding season, respectively. Small, medium, large and the total number of ovarian follicles, oocyte yield and quality were measured. In Experiment 2, the effect of methods of oocyte retrieval and needle gauge on oocyte yield and quality was evaluated with oocytes recovered using slicing and aspiration with 18-, 19- or 20-gauge needle. Oocytes were evaluated microscopically and classified into three categories. The objective of Experiment 3 was to identify the optimum time for oocyte maturation in the dromedary camel. Oocytes were cultured in CR1aa medium at 38.5 degrees C under 5% CO(2) for 24, 32, 36, 48 and 72h. Maturation was calculated as the percentage of cumulus expansion and oocytes reaching metaphase II (MII). The number of small, medium, large and the total number of ovarian follicles were higher (P<0.01) during the breeding than non-breeding season. The recovery of total number of oocytes and Category I oocytes were also greater (P<0.01) during the breeding season. Ovaries without a CL possessed significantly (P<0.01) more ovarian follicles and more (P<0.05) small and large follicles. The total number of oocytes and Category I oocytes were also greater (P<0.01) in ovaries without CL. Slicing of camel ovaries increased (P<0.01) the yield of oocytes as compared to aspiration. The aspiration of follicles using a 20-gauge needle had greater yields of the total number of oocytes and Category I oocytes than when using 19- (P<0.05) and 18-gauge needle (P<0.01). The culture of camel oocytes for 36h produced higher (P<0.01) percentages of cumulus expansion and oocytes at MII. Increasing culture times up to 48 or 72h increased (P<0.01) the percentage of degenerated oocytes. In conclusion, the growth and development of ovarian follicles in the camel as well as yields of Category I oocyte were greater during the breeding season. Slicing or aspirations using a 20-gauge needle yielded greater numbers of total and Category I oocytes. Finally, maturation of oocytes in CR1aa medium for 36h produced higher percentages of cumulus expansion and oocytes at MII stage.

Animals↗