bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of Genotype–Environment Interaction on the Grain Yields of 10 Pigeonpea Cultivars Grown in Kenya
Authors: Wamatu J. N. , Thomas E.
Published: March 2003

To study the importance of the effects of genotype–environment interactions on the yield of pigeonpea (Cajanus cajan L. Millsp.), 10 early‐maturing genotypes were grown in a randomized complete block design with three replications in a total of seven environments spread over five regions of Kenya between 1987 and 1988. Results indicated the presence of a substantial genotype–environment interaction effect on grain yield. The observed significant genotype–environment interaction effect is discussed in relation to its importance in pigeonpea grain yield evaluation studies. It is noted that the best genotype in one environment is not always so in other environments. Results from regression analysis indicated that this method of analysis is appropriate for describing the response of pigeonpea genotypes grown in a number of locations. Analysis of variance showed significant additive and multiplicative genotype–environment interaction effects. Only the first interaction principal component axis (IPCA) was found to be important in describing the multiplicative interaction effects. The additive main effects and multiplicative effects (AMMI) model allowed the partitioning of interaction variance into agronomically important sources (genotype groups), and the specific genotype × environment patterns that are the basis of these sources of variance were examined.
A new HpaII PCR‐RFLP within the porcine prolactin receptor (PRLR) gene and study of its effect on litter size and number of teats
Authors: PUTNOVÁ L. , KNOLL A. , DVOŘÁK J. , ČEPICA S.
Published: March 2003

DNA polymorphism of the porcine prolactin receptor gene (PRLR) was investigated and used to study its effect on litter size and number of teats in pigs. By means of PRLR gene sequence homology in pig, human and other species, primers were designed for PCR amplification within 5′ unknown (to date) part of the prolactin receptor gene in pigs. In this part of the gene, a new polymorphism with HpaII restriction endonuclease was detected. AluI polymorphism described before and our new HpaII polymorphism were used to study the associations with reproduction traits. The PCR restriction fragment length polymorphism (PCR‐RFLP) method was used to genotype AluI and HpaII loci of the PRLR gene in line A with 83 sows of Landrace breed and in two lines (B and C) with 75 and 86 Large White sows, respectively. Statistical analysis of 1020 litters showed that AluI locus was associated with litter size mainly in Landrace and affected the first parities, while HpaII locus of the gene was associated with the same traits in Landrace and Large White pigs and mainly affected numbers of weaned of pigs. The magnitude of the effect varied by population with the effects exceeding two pigs per litter in Landrace line and 1 pig per litter in Large White populations.
Genetic parameter estimates for birth weight, weaning weight and average daily gain in pure and crossbred sheep in Ethiopia
Authors: Hassen Y. , Fuerst‐Waltl B. , Sölkner J.
Published: March 2003

Data for birth weight (BW), weaning weight (WW) and pre‐weaning average daily body weight gain (ADG) of seven different genotypes of lambs (pure Awassi (A), n = 80, pure local (L), n = 3300, lambs with 10 to <50% A × L n = 137, 50% A × L n = 1142, >50 – <75% A × L n = 273, 75% A × L n = 800, and >75% A × L n = 904) were used to estimate genetic parameters. Fixed effects included in the model were genotype (with or without), type of birth, sex, season × year of birth combination. All fixed effects were significant. (Co)variance component estimates were obtained from bivariate animal model analysis including maternal genetic and maternal permanent environmental effects. Direct additive (co)variances and correlations among the traits were positive. Genetic antagonism existed between direct and maternal effects for all traits.

 Direct heritabilities (h) for BW, WW and ADG were 0.39, 0.33 and 0.25 (with genotype) and 0.28, 0.31 and 0.25 (without genotype). The corresponding maternal heritabilities (h) were 0.13, 0.18 and 0.19 and 0.19, 0.18 and 0.18, respectively. Both, maternal genetic and maternal permanent environmental effects were important.
Effects of dietary protein quality on protein turnover in growing pigs
Authors: Saggau E. , Schadereit R. , Beyer M. , Susenbeth A. , Voigt J. , Hagemeister H.
Published: March 2003

To estimate the long‐term effects of dietary protein quality (AA pattern) on whole‐body protein synthesis and degradation in growing pigs two experiments were carried out each using four barrows per treatment group, which were fed semisynthetic isoenergetic diets based on either casein or soy protein isolate at 1875 kJ ME/(kg (BW)0.62× day). Casein was tested with (CAS+) amino acid (AA) supplementation and soy protein isolate was tested with (SPI+) and without (SPI−) AA supplementation, respectively. The effects of dietary protein quality were studied at the recommended protein supply of 100% (normal protein level (NP), experiment 1 and at a protein supply of 50% of NP (low protein level (LP), experiment 2. In experiment 1 measurements were carried out with pigs of 40–90 kg BW and in experiment 2 with pigs of 40–60 kg BW. During the experiments pigs were housed individually in metabolic cages at 23 ± 1°C. Protein deposition was determined by the nitrogen balance method during 8 days. The whole‐body protein synthesis was derived from the cumulative urinary 15N excretion up to 48 h after application of a single dose of [15N]glycine. Calculations were based on a three compartment model. At both protein supply levels, feeding of SPI− with the lower biological value resulted in significantly lower protein deposition than feeding of CAS+. This was a result of a simultaneous decrease of protein synthesis and degradation. Due to the lower requirement for essential AA of the older pigs, the differences in protein deposition and turnover rates between CAS+ and SPI− decreased with increasing BW. Because the efficiency of protein synthesis (ratio of deposition to synthesis) was not altered in response to the dietary protein quality at both protein supply levels, it is concluded that with inadequate AA supply the protein turnover runs on a lower basal level than with adequate AA supply. Intravenous [15N]glycine administration caused approximately 30% higher estimates of whole‐body protein synthesis than oral [15N]glycine administration did in identical CAS+‐fed pigs of about 90 kg BW. This finding is consistent with literature data. However, because this relation is not yet verified in SPI−‐fed and in younger pigs, the effect of dietary protein quality on protein turnover can only be compared within both protein levels.
The effect of chlorocholine chloride (CCC) inclusion in the diets of growing hens on growth rate, oestrogen levels and the onset of lay
Authors: Gultom D. , Songsang A. , Ter Meulen U.
Published: March 2003

A study was conducted to test the effect of chlorocholine chloride (CCC) on growth performance and the onset of laying in hens. One hundred and fifteen 3‐week‐old chickens were divided into four treatment groups of 39, 33, 31 and 12 chickens. They were placed on four dietary treatments consisting of 0 p.p.m. CCC (control), 5 p.p.m. CCC from 14 weeks of age (5 p.p.m. A), 5 p.p.m. CCC from the beginning (5 p.p.m. B), and 50 p.p.m. CCC from the beginning (50 p.p.m. B). The basal diets were formulated according to the growing period and were iso‐nitrogenous and iso‐energetic. The crude protein content was 17.99% dry matter and 14.63% dry matter during the first 3–8 weeks and 9–20 weeks, respectively. The energy content was 12.7 and 12.75 MJ metabolisable energy (ME)/kg dry matter for the respective two growth phases. Feed intake, bodyweight changes and egg production were measured. Blood samples for oestrogen determination were collected weekly from the 15th week until the first egg was laid. Depressive effects of 50 p.p.m. CCC on bodyweight gain during weeks 3–8 and feed efficiency over the whole period were observed. There were no treatment differences (p > 0.05) on feed intake, bodyweight gain during weeks 9–20 and age at the point of lay. CCC inclusion at 50 p.p.m. significantly (p < 0.05) stimulated the oestrogen concentration at 17 and 18 weeks of age, and was 65% higher than the control at 18 weeks.
Small intestinal digestibility of microbial and endogenous amino acids in dairy cows
Authors: Larsen M. , Madsen T. G. , Weisbjerg M. R. , Hvelplund T. , Madsen J.
Published: March 2003

The small intestinal digestibility of microbial amino acids and the apparent re‐absorption of endogenous amino acids were estimated in three ruminal, duodenal and ileal fistulated lactating dairy cows. The cows were assigned to a 3 × 3 Latin square and fed diets low in amino acids, composed of straw, starch, molasses and urea. The treatments were three straw to concentrate ratios. The digestibilities and re‐absorptions were estimated from duodenal and ileal flows of amino acids from feed, microbial and endogenous sources. The duodenal distribution of amino acids between different origins was determined by the difference method and by the amino acid profile method. The ileal distribution was estimated by a simple method where the feed fraction was estimated by the mobile bag method, the endogenous fraction as the water soluble fraction and the microbial fraction as the rest. In ileal samples, 8.0 ± 1.1, 52.2 ± 2.9 and 39.8 ± 2.6% of total amino acid nitrogen (AAN) were of feed, microbial and endogenous origin, respectively, compared with 5.1 ± 0.9, 61.6 ± 6.6 and 32.7 ± 6.9% in duodenal samples. The small intestinal digestibility of microbial AAN was estimated to be 75.1 ± 1.8% and the apparent re‐absorption of endogenous AAN to be 62.3 ± 11.1%.
Fermentation of liquid coproducts and liquid compound diets: Part 2. Effects on pH, acid‐binding capacity, organic acids and ethanol during a 6‐day storage period
Authors: Scholten R. H. J. , Rijnen M. M. J. A. , Schrama J. W. , Boer H. , Van Der Peet‐Schwering C. M. C. , Den Hartog L. A. , Vesseur P. C. , Verstegen M. W. A.
Published: March 2003

The effects of a 6‐day storage period on changes in pH, acid‐binding capacity, level of organic acids and ethanol of three liquid coproducts [liquid wheat starch (LWS), mashed potato steam peel (PSP) and cheese whey (CW)] and two liquid compound diets [liquid grower diet (LGD) and liquid finisher diet (LFD)] were studied. All products, except LWS, showed a significant decrease in pH and acid‐binding capacity during storage. At the end of the storage period, all products reached a pH of between 3.5 and 3.9. In general, it can be concluded that the lactic acid content, and to a lesser extent the acetic acid content, increased dramatically during storage. In contrast, the ethanol content increased significantly in the liquid compound diets only. The pattern of changes in pH and organic acids during the 6‐day storage period was different between the liquid coproducts and the liquid compound diets. At the start of storage, liquid coproducts are already in the ‘middle’ of the fermentation process, while liquid compound diets need approximately 24–36 h before fermentation begins. Consequently, in practice a different approach to obtain fermented diets is needed for liquid coproducts and liquid compound diets.
Effects of dietary chromium picolinate supplementation on performance and plasma concentrations of insulin and corticosterone in laying hens under low ambient temperature
Authors: Şahin K. , Küçük O. , Şahin N.
Published: March 2003

This experiment was conducted to evaluate the effects of chromium (chromium picolinate) on performance and plasma concentrations of insulin and corticosterone of laying hens (Ross Brown) under a low ambient temperature (6.9 °C). One hundred and twenty laying hens (46 weeks old) were divided into four groups, 30 hens per group. The laying hens were fed either a control diet containing 710.3 p.p.b. chromium or the control diet supplemented with 100, 200 or 400 μg chromium/kg diet. Increasing supplemental chromium increased live weight change (p ≤ 0.001, linear) and egg production (p ≤ 0.001, linear) and also improved feed efficiency linearly (p ≤ 0.001). Live weight change and egg production also had quadratic responses (p ≤ 0.001) to increasing chromium supplementation. Plasma insulin concentration increased linearly (p ≤ 0.001), whereas corticosterone concentration decreased linearly (p ≤ 0.001) as dietary chromium supplementation increased. The results of this study indicate that supplemental dietary chromium, 200 p.p.b. in particular, had a positive effect on performance and increased the plasma insulin concentration of laying hens under cold stress.
Prediction of protein digestibility in dog food by a multi‐enzymatic method: a useful technique to develop
Authors: Tonglet C. , Jeusette I. , Istasse L. , Diez M.
Published: March 2003

The multi‐enzymatic method with constant pH described by Dufour‐Etienne et al. (Rec. Méd. Vét. 168, 789–796, 1992) was tested using 17 industrial dry dog foods and two ingredients, sodium caseinate and beef meat, which were used as references. The quantity of sodium hydroxide added to the enzymatic solution was measured after incubation times of 2, 5 and 10 min and the best prediction of the apparent protein digestibility was obtained with an incubation time fixed at 2 min. The volume of sodium hydroxide 0.1 N constantly added to maintain the pH of the solution at 8 was correlated to the value of in vivo digestibility of the protein measured in the dog. The correlation coefficient obtained was 0.90 with a standard error of the regression of 1.9 for all samples. The correlation coefficients calculated for incubation times of 5 and 10 min were lower than that at 2 min; thus an incubation period of 2 min provided the highest correlation coefficient for this multi‐enzymatic method at constant pH. However, considering the lack of samples with an apparent protein digestibility ranging between 85 and 95%, the slope of the regression line and the correlation coefficient were strongly influenced by the ingredients, such that when the correlation coefficient was calculated for 17 dog foods without the reference ingredients, a coefficient of 0.71 (± 1.9) was obtained. These tests of in vitro digestibility are valuable to predict the apparent digestibility of the protein in the dog, but, it is essential to confirm the results by an in vivo test.
A bait formulated with Metarhizium anisopliae for the control of Musca domestica L. (Dipt., Muscidae) assessed in large‐scale laboratory enclosures
Authors: Renn N. , Bywater A. F. , Barson G.
Published: March 2003

The entomopathogenic fungus Metarhizium anisopliae was formulated into a bait for assessment against Musca domestica (housefly). Its efficacy was tested by placing either one, two or four baits on the floor of a 10 m3 polythene cubicle and releasing 100 female and 50 male M. domestica. One, two or four baits had equal effects and, between 95.2 and 100% of flies were killed after 10 days. In a second experiment, the durations of visits by single or pairs of flies to the baits and subsequent pick‐up of conidia were recorded. Single flies remained in the baits for up to 33 min and picked up a mean of 38 235 ± 8291 conidia. When pairs of flies were exposed, the individuals picked up a mean of 95 879 ± 23 838 conidia, which was significantly more (P < 0.05) than the single flies, although the mean duration of the visits was not significantly different (P > 0.05). However, the numbers of conidia picked up by the flies did not correlate with the duration of the visit. Lastly, 25 female and 25 male flies were exposed in 0.027 m3 arenas, to 10 M. anisopliae‐killed houseflies, showing sporulating hyphae. After 8 days, 97.3% of female flies and 100% of male houseflies had succumbed to infection with M. anisopliae. The implications of these observations are discussed.
Preference and performance responses of California grape phylloxera to different Vitis rootstocks
Authors: Omer A. D. , Granett J. , Kocsis L. , Downie D. A.
Published: March 2003

Laboratory experiments on host preference and performance were simultaneously conducted with Cabernet Sauvignon, AXR#1, and 5C Vitis rootstocks for the California biotypes A and B grape phylloxera. Preference bioassays recorded over a 3‐day period indicated that phylloxera exhibit differential host choice. AXR#1 is antixenotic to biotype A, and 5C is antixenotic to both phylloxera biotypes. Preferences observed with biotype B for Cabernet Sauvignon and AXR#1 were not statistically different, whereas biotype A had shown a significant preference for Cabernet Sauvignon. On 5C the preferences scored were significantly lower than on either of the other two rootstocks, and there was no significant difference beetween biotypes. Performance bioassays recorded over a 29‐day period indicated that survival, development, and reproduction of both biotypes were affected by Vitis rootstock. Both biotypes were unable to survive or develop on 5C suggesting the presence of antibiotic resistance in 5C against these phylloxera biotypes. The antibiotic effects observed with AXR#1 against biotype A were expressed as significant reductions in survival, development, and reproduction. Performance of biotype B on AXR#1 was similar to its performance on Cabernet Sauvignon. For both AXR#1 and 5C rootstocks and both phylloxera biotypes A and B the antibiotic mechanism was considerably stronger than the antixenotic mechanism. This research indicated that host preference and performance are positively correlated in grape phylloxera with the rootstocks and phylloxera biotypes tested.
Waxfilm (Pat. pend.): an alternative film for rearing parasitoids of Anthonomus grandis (Col., Curculionidae)
Authors: Aquino I. S. , Ramalho F. S. , Payton M. R. , Eikenbary R. D.
Published: March 2003

Abstract: Reducing the impact of insecticides on the environment is a matter of concern to researchers and the use of parasitoids for controlling pests is ecologically preferred. One of the methods used in the mass rearing of parasitoids requires the use of Parafilm®‘M’. This film is inconvenient for use in Brazil because of import restrictions and import duties. Waxfilm (Pat. pend.) is a film made from beeswax (Apis mellifera L.) that does not depend on importation, is 100% natural, 100% recyclable and 100% biodegradable. This film is used in the laboratory as an artificial flower bud, in which boll weevil Anthonomus grandis Boheman larvae are placed and then exposed to parasitoids. Research was conducted at a temperature of 25 ± 2°C and a relative humidity of 70 ± 5%. Bracon sp. and Catollacus grandis (Burks) parasitoids were tested for rearing using both films. The results show that, on the basis of the number of parasitoids that emerged, Waxfilm is as efficient as Parafilm®‘M’. This new film could have a large impact on biological control programmes in developing countries, where the use of cheap and locally available materials is very important to the successful implementation of new technologies. This would also provide increased income to indigenous beekeepers.
Effect of phenylalanine and tyrosine analogues on Bactrocera oleae Gmelin (Dipt., Tephritidae) reproduction
Authors: Zografou E. N. , Tsiropoulos G. J. , Margaritis L. H.
Published: March 2003

The effect of nine phenylalanine and tyrosine analogues at various concentrations upon the reproduction of adult olive fruit fly Bactrocera oleae Gmelin (Diptera, Tephritidae), was tested. Fecundity (eggs/female/day) and percentage egg hatchability was significantly reduced by the following anti‐amino acids (in parentheses are indicated the antagonized amino acid): p‐fluoro‐DL‐phenylalanine (phe), p‐amino‐DL‐ and ‐L‐phenylalanine (tyr), 3‐amino‐L‐tyrosine (tyr) and L‐mimosine (tyr), at concentrations of 0.1, 0.25, 0.05 and 0.5% in the diet, respectively. Hatchability was also affected by two other analogues of phenylalanine and tyrosine, p‐bromo‐DL‐phenylalanine at a concentration of 10% and m‐fluoro‐DL‐tyrosine at a concentration of 1.5%. Insect survival was affected only by p‐fluorophenylalanine and 3‐amino‐L‐tyrosine at concentrations 0.25 and 6%, respectively. No significant differences were observed between the survival of the two sexes. Finally, β‐2‐thienyl‐DL‐alanine (phe) and α‐methyl‐DL‐p‐tyrosine (tyr) did not affect any of the parameters tested. Electron microscopy examination of the follicles and the egg‐shell structure of eggs laid by females fed with diets containing p‐amino‐L‐phenylalanine and 3‐amino‐L‐tyrosine, revealed abnormalities related to the egg‐shell fine structure.
Side‐effects of three neem (Azadirachta indica A. Juss) products on the predator Macrolophus caliginosus Wagner (Het., Miridae)
Authors: Tedeschi R. , Alma A. , Tavella L.
Published: March 2003

The side‐effects of three neem formulations (Neem‐Amin EC, Stardoor and B.P. 20/S) were tested on the mirid predator Macrolophus caliginosus Wagner in the laboratory. Direct toxicity tests on 1st instar nymphs exposed to fresh dry residues on glass plates at different doses demonstrated that all the products are harmful to the insects with LD50 values much lower than the maximum recommended rate (1.217, 0.264, 1.083 mg a.i./l instead of 15, 31.5 and 80 mg a.i./l for Neem‐Amin EC, Stardoor and B.P. 20/S, respectively). Moreover a reduction of fecundity of the surviving females was assessed with Neem‐Amin EC and B.P. 20/S. Persistence tests were carried out on sharp pepper plants treated at the maximum recommended rate. High mortality was recorded when the insects were introduced onto the plants just after the treatment, but no significant differences compared with the controls were observed 5 days after the treatment and any consequence on the fecundity of surviving females was detected. Our experiments showed how azadirachtin can be noxious to M. caliginosus, but the short persistence makes this active ingredient a promising solution in integrated pest management programmes, when a lapse of time is guaranteed between the treatment and the introduction of the predator.
Effect of the entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorokin on cellular defence response and oxygen uptake of the wax moth Galleria mellonella L. (Lep., Pyralidae)
Authors: Sewify G. H. , Hashem M. Y.
Published: March 2003

Remarkable changes in the cellular response and oxygen uptake in the wax moth Galleria mellonella were observed when larvae were infected with the entomopathogenic fungus Metarhizium anisopliae. The number of haemocytes increased 48, 72 and 96 h after infection with fungal conidiospores. Extensive blebbing of the cell membrane in the haemocytes and large numbers of vacuoles were noticed as a result of fungal infection. The study showed a significant difference in oxygen uptake between healthy and infected larvae and the greatest uptake was recorded 72 h after fungal infection. The results suggested that the rate of cellular reaction and oxygen uptake were associated with the development of fungal infection.
Efficacy of extracts of Melia azedarach L. callus, leaves and fruits against adults of the sweetpotato whitefly Bemisia tabaci (Hom., Aleyrodidae)
Authors: Hammad E. M. Abou‐Fakhr , Zournajian H. , Talhouk S.
Published: March 2003

Bioassays with extracts of callus, fruit and leaves of the Chinaberry tree, Melia azedarach L., were performed against adults of Bemisia tabaci (Gennadius). Tissue culture of M. azedarach was carried out in Murashige and Skoog (MS) medium supplemented with indole butyric acid and benzyl adenine. Fresh and frozen leaves or fruits and the callus product were extracted in water or methanol at a ratio of 1 : 5 (w/v) for 48 h. The aqueous and methanol extracts were applied on tomato plants to determine their effect on B. tabaci adults and their corresponding oviposition and consequent adult emergence in comparison with the control, distilled water. Results have shown that extracts of callus and different age classes of M. azedarach leaves and fruits have shown significant repellent activity of 58.9–67.7% and have significantly decreased the oviposition rate of the insect without affecting the adult whitefly emergence in comparison with the control. Aqueous and methanol extracts have shown comparable effects against adult whiteflies indicating a similar efficacy of the two solvents in extracting the bioactive components of Melia. Extracts of frozen samples were found to be as effective against the pest as fresh samples, thus allowing storage of Melia parts to be used in case of shortage. This is the first report of the use of M. azedarach callus against B. tabaci; the M. azedarach callus, leaf and fruit extracts seem to present a potential source for management of B. tabaci.
Cotton pests and their natural enemies in Madagascar
Authors: Kuklinski F. , Borgemeister C.
Published: March 2003

An update on the cotton pest complex and its associated natural enemies in Madagascar is provided. Since the end of the 1970s, when the previous reports had been published, the population dynamics of the principal pests in Malagasy cotton have undergone considerable changes. The American bollworm Helicoverpa armigera Hübner (Lep., Noctuidae) is still a limiting factor for production and can be considered the key pest, whereas the Egyptian leaf worm Spodoptera littoralis Boisduval (Lep., Noctuidae) and the cotton aphid Aphis gossypii Glover (Hom., Aphididae) have become significant pests as a result of indiscriminate use of synthetic pyrethroids in the 1980s. New records of beneficials, in particular the discovery of the aphidopathogenic fungus Neozygites fresenii (Nowakowski) (Entomophthorales) in cotton aphid populations, are reported. Strategies to preserve predator populations in view of reducing disruptive insecticide treatments are discussed.
Mortality of Delia floralis, Galleria mellonella and Mamestra brassicae treated with insect pathogenic hyphomycetous fungi
Authors: Klingen I. , Meadow R. , Aandal T.
Published: March 2003

Abstract:  The susceptibility of Delia floralis eggs, neonates and larvae and the susceptibility of Galleria mellonella and Mamestra brassicae larvae to seven different Norwegian isolates of the insect pathogenic, hyphomycetous fungi Tolypocladium cylindrosporum, Metarhizium anisopliae and Beauveria bassiana, were investigated. Metarhizium anisopliae isolate ARSEF 5520 was highly virulent to G. mellonella larvae and caused 100% mortality when tested at a concentration of 3.6 × 106 conidia/ml. The same M. anisopliae isolate was not virulent to D. floralis larvae. Isolates of T.cylindrosporum, were equally virulent to G. mellonella and D. floralis causing up to 36.0% mortality of larvae. It is suspected, however, that the use of grated rutabaga as a food source in the D. floralis bioassay reduced the fungal virulence of both M. anisopliae and T. cylindrosporum to D. floralis. Among three T. cylindrosporum isolates tested at a concentration of 1.0 × 107 conidia/ml against eggs of D. floralis none of them reduced the hatching percentage. One isolate, ARSEF 5525 did, however, significantly reduce the longevity of neonates. Beauveria bassiana isolates ARSEF 5510 and ARSEF 5370 tested at a concentration of 1.0 × 107 conidia/ml resulted in M. brassicae mortality levels of 70.0 and 55.0%, respectively. The B. bassiana isolate ARSEF 5557, however, was not virulent to M. brassicae. Among the three isolates tested against M. brassicae the two virulent isolates produced a red pigment, probably oosporein, when cultured in Sabouraud dextrose agar.
The efficacy of an improved form of the mass‐trapping method, forthe control of the olive fruit fly, Bactrocera oleae (Gmelin) (Dipt., Tephritidae): pilot‐scale feasibility studies
Authors: Broumas T. , Haniotakis G. , Liaropoulos C. , Tomazou T. , Ragoussis N.
Published: March 2003

Abstract:  The efficacy of an improved form of the mass‐trapping method for the control of the olive fruit fly, Bactrocera oleae (Gmelin) was tested for 4 years in a pilot test at Tanagra Voeotia, Greece. Improvements consisted of the extension of the active life of the toxic trap used, active life referring both to its attracting and killing properties, as well as in trap deployment, which combined efficacy and low cost. The method was compared to bait sprays applied from the ground, which constitutes the current standard method for the control of this pest. Both pest population density and fruit infestation levels, the main parameters used for the evaluation of the two methods were considerably lower during all 4 years of tests in the orchards protected by mass trapping compared with those in the orchards protected by bait sprays. Furthermore no complementary measures were required in the mass‐trapping orchards for acceptable crop protection, which was not the case under certain conditions, prior to the introduction of the recent improvements. The cost of the mass‐trapping method was approximately US$ 0.40 per tree per year compared with US$ 0.35 for bait sprays (figures of the Greek Ministry of Agriculture). However, the mass‐trapping method reduces the amount of insecticide used for olive protection by 99.5% (15 mg a.i. per tree per year as opposed to 3 g in the case of bait sprays). A considerable reduction in the cost of the mass‐trapping method is expected with the extension of its use and the mass production of materials used, especially traps.
Potential of some Metarhizium anisopliae isolates for control of Culex quinquefasciatus (Dipt., Culicidae)
Authors: Alves S. B. , Alves L. F. A. , Lopes R. B. , Pereira R. M. , Vieira S. A.
Published: March 2003

Abstract: The potential of some isolates of Metarhizium anisopliae and Beauveria bassiana for use in the integrated management of Culex quinquefasciatus was evaluated. Metarhizium anisopliae isolate 1037 was selected in initial bioassays with a 50% lethal concentration (LC50) of 1.97 × 104 conidia/ml. This fungus caused higher mosquito larva mortality when applied as a conidial suspension to the surface of the water than as dry conidia, with a time to 50% lethal (LT50) of 1 day compared with 3.6 days for the dry conidial application. However, results with UV‐ and heat‐inactivated conidia did not confirm a possible role of fungal toxins in causing mortality when ingested by C. quinquefasciatus larvae. Metarhizium anisopliae did not remain active for as long as the bacterium Bacillus sphaericus isolate 2362. At 24 h after application, the fungus‐induced mortality on mosquito larvae was significantly lower than the mortality caused by the bacterium. By the second day, almost no activity by the fungus was observed. Results suggest that M. anisopliae isolate 1037 has potential for use in mosquito control programmes.
Factors of between‐ and within‐plant distribution of Metopolophium dirhodum (Hom., Aphididae) on small grain cereals
Authors: Honěk A. , Martinková Z.
Published: March 2003

Abstract: The relationship between abundance of rose‐grain aphid Metopolophium dirhodum (Walker) and leaf chlorophyll content of spring wheat, spring oats and winter barley was investigated. Within production stands of each crop 18–25 plots were established, located at places with different plant quality where aphids were counted on particular leaves of 50–100 tillers, and the leaf chlorophyll content and area were determined. In all stands aphid numbers × tiller−1 increased exponentially with chlorophyll content (r2 = 0.783–0.933). This parallel variation may be explained by increased nitrogen content and assimilate production of vigorous chlorophyll‐rich plants. The aphid numbers on leaves of particular order (within‐plant distribution) were also correlated with leaf chlorophyll content (r2 = 0.373–0.827). However, in oats and barley the analysis of variance of residuals of log aphids × leaf−1 versus leaf chlorophyll regression revealed a significant effect of leaf position (the order of the leaf from the top of the plant). The magnitude of residuals was positively related to leaf size and may be related to the intensity of phloem transport from the source leaves to sink organs.
Influence of azadirachtin on development and reproduction of Nezara viridula L. (Het., Pentatomidae)
Authors: Riba M. , Martí J. , Sans A.
Published: March 2003

Abstract:  The potential of azadirachtin as an insect growth regulator was evaluated in Nezara viridula L. by applying different doses to fifth instar nymphs. At doses of 200–500 ng per insect almost all the individuals died during moulting to adults and the survivors showed a great number of nymphal characteristics, and also died very soon after. At lower doses, from 2 to 50 ng per insect, approximately 50% of the adults seemed normal. No effect was observed during the last nymphal instar, even at the highest dose applied. The fertility and fecundity of adults, males and females, developing from nymphs treated with different low doses of azadirachtin were also studied. When azadirachtin was applied at 20 ng per insect on fifth instar nymphs, females developing from these nymphs showed a conspicuous reduction of fecundity. This same effect was evident when untreated females mated with males obtained from treated nymphs. Finally, azadirachtin applied at 1 μg/cm2 to the oviposition surface showed a remarkable oviposition repellency.
Differentiation of Dasheen Mosaic Potyvirus Isolates Based on Variability in the Apparent Size of the Capsid Protein in Western Blots
Authors: Li R. H. , Zettler F. W. , Hiebert E. , Purcifull D. E. , Morales F. J.
Published: March 2003

The capsid protein (CP) sizes of seven dasheen mosaic virus (DsMV) isolates and one isolate of vanilla mosaic virus were estimated to be 38–47 kDa and 47 kDa, respectively, based on Western blot analyses using DsMV polyclonal antiserum. The CP sizes of 12 other potyviruses were estimated to be 31–36 kDa. Apparent CP sizes of the DsMV isolates extracted from their original hosts were 47 kDa (Xanthosoma caracu), 45 kDa (Colocasia esculenta, Zantedeschia aethiopica), and 38–46 kDa (Caladium hortulanum). Propagation in seedlings of Philodendron selloum did not affect the CP sizes of any of the individual DsMV isolates. The same characteristic CP sizes were also detected in Western blot analyses of these isolates, using polyclonal antisera of eight other potyviruses, or using Agdia Poty 1 monoclonal antiserum, and using three monoclonal antisera of papaya ringspot virus type W. The apparent CP size and pattern of apparent breakdown products as revealed by Western blots of extracts from infected aroids may be used in the characterization and differentiation of DsMV isolates.
Biological Control of Protomycopsis phaseoli, the Causal Agent of Leaf Smut of Cowpea
Authors: Adejumo T. O. , Ikotun T. , Florini D. A.
Published: March 2003

Among the bacteria and fungi associated from the soil where cowpea was grown and tested for antagonism against Protomycopsis phaseoli, Bacillus sp. inhibited the radial growth, Fusarium oxysporum, yeast, Aspergillus fumigatus, Trichoderma harzianum, Trichoderma koningii and Trichoderma sp. reduced radial growth of P. phaseoli. In vitro studies showed that T. harzianum was an active hyperparasite and more effective in reducing the radial growth of P. phaseoli than T. koningii and Trichoderma sp. Spore suspensions of the three Trichoderma spp. prevented the germination of chlamydospores of P. phaseoli. In the field, when applied as spray, Trichoderma sp. was found to be more active in reducing the spread of leaf smut disease than T. harzianum and T. koningii.
Pathogénie comparée de 4 espèces d'Helminthosporium Obtenues à Partir des Plantes Malades du Riz au Maroc
Authors: Touhami A. Ouazzani , Ennaffah B. , Douira M. El Yachioui et A.
Published: March 2003

L'étude du comportement de quatre espèces d'Helminthosporium sur neuf variétés de riz largement cultivées au Maroc, a permis de classer ces espèces selon leur virulence. L'Helminthosporium oryzae et l'Helminthosporium sativum sont les plus virulents et sont les mieux équipés à sporuler sur les lésions développées sur toutes les variétés de riz testées. Le niveau de pathogénie de l'H. spiciferum et de l'H. australiensis et leur aptitude à sporuler sur l'hôte dépend de la variété du riz étudiée. De même, chaque Helminthosporium induit sur les feuilles de riz des symptômes caractéristiques.
Effects of Fusaric Acid on Reactive Oxygen Species and Antioxidants in Tomato Cell Cultures
Authors: Kuźniak E.
Published: March 2003

Generation of O2– and H2O2 as well as the activities of superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, dehydroascorbate reductase and ascorbate content were studied in tomato cell cultures in response to fusaric acid – a nonspecific toxin of phytopathogenic Fusarium species. Toxin treatment resulted in decreased cell viability which was preceded by culture medium alkalinization up to 0.65 pH unit and enhanced extracellular O2– production. The H2O2 level was not significantly affected. In toxin‐treated cultures, a transient, significant increase occurred in intracellular superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase activities. Fusaric acid‐induced ascorbate turnover modulation led to up to a twofold increase in dehydroascorbic acid accumulation, and a decrease in the associated ascorbate redox ratio. It was concomitant with a significant decrease in dehydroascorbate reductase activity. These results support previous observations that the pro‐ and anti‐oxidant systems are involved in response to fusaric acid treatment although differential response of H2O2 and its metabolism‐related enzymes between the whole leaf and cell culture assays was found.
Antifungal Activity of the Essential Oil of Hyssop (Hyssopus officinalis)
Authors: Letessier M. P. , Svoboda K. P. , Walters D. R.
Published: March 2003

The antifungal and fungicidal effects of hyssop (Hyssopus officinalis) oil and its individual components were studied in a series of in vitro and in vivo experiments. Mycelial growth of the plant pathogenic fungi Pyrenophora avenae and Pyricularia oryzae was completely inhibited by 0.4% hyssop oil. Volatile components diffusing from agar medium containing 0.4% hyssop oil also completely inhibited the growth of these two fungi. Various components of hyssop oil (L‐bornyl acetate, isopinocampheol and pinocamphone), used individually, reduced growth of P. avenae and, where combinations of individual components were used, any mixture containing isopinocampheol completely inhibited fungal growth. Growth of P. oryzae was less affected by individual components of the oil. Hyssop oil reduced germination of Botrytis fabae conidia and uredospores of Uromyces viciae‐fabae, but in contrast to the data from in vitro experiments, its effects on pathogen infection were less clear cut. Thus, although 0.05% hyssop oil reduced rust infection of broad bean when applied 1, 2 or 3 days before, or 1 or 2 days after inoculation, its effects against barley powdery mildew and apple powdery mildew were variable. It is suggested that this variability might be the result of the volatile components of the oil diffusing away from leaf surfaces, thus reducing the concentration of active components on the leaf surface.
Simultaneous PCR Detection of the Two Major Bacterial Pathogens of Geranium
Authors: GLICK D. L. , COFFEY C. M. , SULZINSKI M. A.
Published: March 2003

Xanthomonas campestris pv. pelargonii (Xcp) and Ralstonia solanacearum (Rs) are the two most important bacterial pathogens of commercially cultivated geraniums (Pelargonium spp.), both causing bacterial wilt and leaf spot. Asymptomatic infections are important reservoirs of infections in commercial growing facilities. Our objective was to design a multiplex PCR (Polymerase Chain Reaction) assay to detect infection by either or both of these pathogens. We used a previously characterized PCR primer pair for Xcp that amplifies a region of 200 bp. In addition, we designed a new primer pair specific for Rs that amplifies a region of 822 bp. With these two primer pairs, we could detect either or both pathogens. As geranium tissue extracts frequently contain inhibitors of the PCR process, a negative PCR could result from either an accurate indication that the plant was pathogen‐free or from a false negative assay. We therefore designed `amplification competence' primers, targeting a portion of the geranium 18 s rRNA gene, and generating a 494‐bp amplification product that confirms amplification competence and validates a negative assay result. Thus, the triple primer pair multiplex PCR screens for the two most important bacterial pathogens of geraniums simultaneously confirms amplification competence for each geranium sample.
Heteropogon triticeus, a New Host of Claviceps sorghi in India
Authors: PAŽOUTOVÁ S. , JOHNSON N. , KOLAŘÍK M. , RAJASAB A. H.
Published: March 2003

Claviceps sorghi occurred on Heteropogon triticeus in Gulbarga, Karnataka, India. Its external sphacelial morphology on this species differed from that on sorghum in having long white sphacelial tips that protruded from spikelets or wound around awns. The tips were formed by parallel synnema‐like hyphae and were covered by a phialide layer that produced elongated macroconidia (7–18 μm) and rounded to oval microconidia (3–5 μm). Unlike the macroconidia, the microconidia failed to germinate. Plated macroconidia underwent secondary sporulation. The white sclerotial stroma consisted of parallel hyphae with cylindrical cells that later became rounded due to accumulation of reserve metabolites. Some of these cells differentiated into a sclerotial rind that accumulated a terracotta‐coloured pigment. RAPD patterns and the rDNA nucleotide sequence confirmed the identity of the species.
Genetic Variation in Fusarium moniliforme Isolated from Seeds of Different Host Species from Burkina Faso Based on Random Amplified Polymorphic DNA Analysis
Authors: KINI K. R. , LETH V. , MATHUR S. B.
Published: March 2003

Random amplified polymorphic DNA (RAPD) analysis was used to assess genetic variation among 28 isolates of Fusarium moniliforme isolated from seed samples of six host species (rice, sorghum, maize, cotton, hibiscus and parkia) collected in Burkina Faso. Score‐able markers (128) were obtained with 20 random decamer primers. Cluster analysis with UPGMA using genetic distances showed that the isolates were of five main groups. In general, isolates from the same host species were found to group together in the same cluster. The isolates from cotton and hibiscus were more closely related to each other than to the isolates from sorghum, rice and maize. Results indicate that host preference is possibly a factor in the differentiation of isolates.
Differentiation of Bulgarian Isolates from Cucumber Mosaic Virus by Serological Methods
Authors: HRISTOVA D. , YORDANOVA A. , MAVRODIEVA V.
Published: March 2003

Cucumber mosaic virus (CMV) is of great importance to the Bulgarian economy and hence a detailed knowledge of its diversity under local geographic and climatic conditions is required. An extended study was carried out on CMV strains the currently occur in Bulgaria. Fifty‐one isolates and strains found in different regions and various crops were biologically characterized and serologically differentiated into subgroups I and II using different variants of enzyme‐linked immunosorbent assay (ELISA) [double antibody sandwich (DAS)‐, antigen‐coated plate (ACP)‐, triple antibody sandwich (TAS)‐ with poly and monoclonal antibodies] and immunodiffusion tests. The ELISA modifications with monoclonal antibodies individually (ACP) or in combination with polyclonal antibodies (TAS‐ELISA) are suitable for mass screening of CMV isolates. The hyperimmune sera against strains from CMV subgroups I and II were very efficient for use in isolate differentiation via gel double immunodiffusion. The results obtained correlated with the polymerase chain reaction and restriction fragment length polymorphism data reported by other authors. The majority of the isolates belonged to subgroup I, whereas 10, mainly from tomato and pepper, belonged to subgroup II. Most of the subgroup II isolates came from the north of Bulgaria. The results of the present study will help to clarify the virus epidemiology and to develop specific control measures.
Effect of Integrating Planting Time, Fungicide Application and Host Resistance on Potato Late Blight Development in South‐western Uganda
Authors: KANKWATSA P. , ADIPALA E. , HAKIZA J. J. , OLANYA M. , KIDANEMARIAM H. M.
Published: March 2003

The presence of inocula all year round poses a daunting challenge to the management of late blight [causal agent Phytophthora infestans (Mont.) De Bary] of Solanum potato in the highlands of eastern Africa. Commercial production depends heavily on use of fungicides and, to some extent, host resistance. In this study, integration of host resistance and fungicide application reduced late blight severity by more than 50% and resulted in yield gains of more than 30% when compared with the untreated control. The study demonstrated that susceptible varieties can be successfully grown in the region if well‐timed fungicide sprays are administered. Under high late blight pressure, fungicide application was necessary but integration of resistant cultivars in late blight management assisted in reducing the amount and frequency of fungicide applications. However, integration of timely planting (early planting) is difficult due to limitations in weather monitoring and the subsistence nature of the farming system in the eastern African highlands.
o‐Hydroxyethylorutin‐Mediated Enhancement of Tomato Resistance to Botrytis cinerea depends on a Burst of Reactive Oxygen Species
Authors: Małolepsza U. , Urbanek H.
Published: March 2003

o‐Hydroxyethylorutin, when applied exogenously to tomato plants was effective in enhancing resistance to Botrytis cinerea infection. Two tomato cultivars, high and low in susceptibility to B. cinerea, were analysed for superoxide anion, hydroxyl radical, hydrogen peroxide generation rates, for changes in lipid peroxidation and activities in superoxide dismutase, peroxidase and catalase. The reactions observed in uninfected tomato plants, in plants infected with B. cinerea, and in those treated with o‐hydroxyethylorutin and infected with the pathogen were compared. The most significant increase in superoxide anion and hydrogen peroxide generation was observed in plants pretreated with o‐hydroxyethylorutin and then infected with the pathogen. It was greater and generally occurred earlier in pretreated, less susceptible plants as compared to more susceptible ones. Some decrease in ascorbate peroxidase activity resulting from inoculation with B. cinerea plants pretreated with o‐hydroxyethylorutin was observed in studied plants. The results indicate that o‐hydroxyethylorutin‐induced tomato resistance to B. cinerea infection depends on its stimulation of reactive oxygen species generation and they confirm the important role of enhanced production of ROS in induced plant resistance reactions.
Production of Perithecia of Various Ascomycotina on Water Agar Medium Emended with Leaf Pieces
Authors: Furukawa T. , Kishi K.
Published: March 2003

A simple agar medium emended with leaf pieces of Hydrangea or Gardenia (ALP) was found to be effective for perithecia and ascospore formation of Glomerella singulata, Mycosphaerella allicina, Metasphaeria sp., Guignardia sp. and Pleospora herbarum which failed to form ascospores on potato dextrose agar (PDA). No perithecia of Gibberella formed on this medium, but sporodochial conidia of Fusarium formed on ALP but not on PDA.