Showing papers by "Universidade Federal de Viçosa published in 2000"

Insecticide resistance in populations of Tuta absoluta (Lepidoptera: Gelechiidae)

Abstract: 1 Control failures of insecticides used against the tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Brazil led to the investigation of the possible occurrence of resistance of this insect pest to abamectin, cartap, methamidophos and permethrin. 2 The insect populations were collected from seven sites in the states of Minas Gerais, Rio de Janeiro, and Sao Paulo. These populations were subjected to concentration–mortality bioassays using insecticide-impregnated filter papers. 3 We were unable to obtain a single population which provided a susceptibility standard for all insecticides tested. Therefore, the resistance levels were estimated in relation to the most susceptible population to each insecticide. Resistance to abamectin and cartap were observed in all populations when compared with the susceptible standard population, with resistance ratios ranging from 5.2- to 9.4-fold and from 2.2- to 21.9-fold for abamectin and cartap, respectively. Resistance to permethrin was observed in five populations with resistance ratios ranging from 1.9- to 6.6-fold, whereas resistance to methamidophos was observed in four populations with resistance ratios ranging from 2.6- to 4.2-fold. 4 The long period and high frequency of use of these insecticides against this insect pest suggest that the evolution of insecticide resistance on them has been relatively slow. Alternatively, the phenomenon might be widespread among Brazilian populations of T. absoluta making the finding of suitable standard susceptible populations difficult and leading to an underestimation of the insecticide resistance levels in this pest. 5 Higher levels of resistance to abamectin, cartap and permethrin are correlated with greater use of these compounds by growers. This finding suggests that local variation in insecticide use was an important cause of variation in susceptibility.

A biodiversity approach in the neotropical erythrinidae fish, Hoplias malabaricus. Karyotypic survey, geographic distribution of cytotypes and cytotaxonomic considerations.

Abstract: Hoplias malabaricus, a widely distributed neotropical freshwater fish, shows a conspicuous karyotypic diversification. An overview of this diversity is presented here comprising several Brazilian populations, and some others from Argentina, Uruguay and Surinam. Seven general cytotypes are clearly identified on the basis of their diploid number (2n=39 to 2n=42), chromosomal morphology and sex chromosome systems, which can be clustered into two major karyotypic groups. This clustering suggests that karyotype structure would be more informative than the diploid number regarding cytotype relationships in this fish group. While some cytotypes show a wide geographical distribution, some others appear to be endemic to specific hydrographic basins. Sympatric cytotypes can occur without detection of hybrid forms; this situation points to a lack of gene flow, a fact that is also reinforced by studies with genomic markers. The karyotypic data support the view that the nominal taxon H. malabaricus corresponds to a species complex comprising distinct evolutionary units, each with well-established chromosomal differences.

Fatores que afetam o consumo alimentar e a nutrição do idoso

Abstract: The factors that affect the aged people food intake are recognized as risk for the development of undernourishment. This article aims at providing a general review about these factors, trying to elucidate the conditions of the Brazilian aged people nutrition. The understanding of these factors by the professionals of health enlarges the knowledge of the peculiar conditions which determine the aged people nutritional status, and which should be worked in an interactive way, for the maintenance or restoration of the normal status.

Cartap resistance and synergism in populations of Tuta absoluta (Lep., Gelechiidae)

Abstract: Control failures of cartap when used against the tomato leafminer Tuta absoluta (Meyrick) in Brazil and a recent report of cartap resistance in Brazilian populations of this pest species led to the investigation of the possible involvement of detoxification enzymes on this phenomenon using insecticide synergists. The insect populations were collected from seven different sites in the states of Minas Gerais, Rio de Janeiro and Sao Paulo. These populations were subjected to insecticide-impregnated filter paper assays. The concentration–mortality assays were carried out for cartap alone and in a mixture (1 cartap : 10 synergist) with the synergists diethyl maleate, piperonyl butoxide and triphenylphosphate which, respectively, inhibit the enzymes glutathion-S-transferases, cytochrome P450-dependent monooxygenases and esterases. Resistance to cartap was observed in all populations when compared with the standard susceptible population, with resistance ratios ranging from 2.3- to 21.9-fold. Piperonyl butoxide was the most efficient synergist with cartap synergism ratios ranging from 1.3- to 21.0-fold and nearly completely suppressing the resistance to cartap in all of the populations studied, suggesting a major involvement of cytochrome P450-dependent monooxygenases as a cartap resistance mechanism in these populations of T. absoluta. Diethyl maleate and triphenylphosphate also synergized cartap in nearly every population, and they still provided partial suppression of cartap resistance in the leafminer populations studied. Therefore, glutathion-S-transferases and esterases seem to play a secondary role in cartap resistance in Brazilian populations of T. absoluta.

Synthesis and insecticidal activity of new amide derivatives of piperine

Abstract: The natural lipophilic amides piperine and piperiline were isolated from Piper nigrum L (Piperaceae). Piperine was hydrolysed into piperic acid (85% yield) which was converted into 16 amides (28–89% yield). The contact toxicity of all synthetic amides, and also that of piperine and piperiline, at the dose 10 µg per insect, was evaluated for the Brazilian economically important insects Ascia monuste orseis Latr, Acanthoscelides obtectus Say, Brevicoryne brassicae L, Protopolybia exigua DeSaus and Cornitermes cumulans Kollar. The results demontrated that the insects have different sensivities to the various amides, with mortality ranging from 0 to 97.5% according to the compound and insect species. © 2000 Society of Chemical Industry

Age-dependent fecundity and life-fertility tables for Podisus nigrispinus (Dallas) (Het., Pentatomidae)

Abstract: The reproductive potential and longevity of Podisus nigrispinus (Dallas) were determined under laboratory conditions at a constant temperature of 25C. The data were used to calculate life-fertility tables and rates of increase. The fecundity plateau of P. nigrispinus lasted 18 days, and during this period mean fecundity was 8.89 eggs per female per day. It started at the eighth day of age and ended at the 18th day of age. The declining fecundity per- iod started at 18 days of age and ended with the death of the females. The female of P. nigrispinus oviposited a mean of 188.54 eggs, and had a mean longevity of 31.21 days. The gross reproductive rate (GRR) was 104.374 females/ female; the net reproductive rate (Ro) was 31.945 females/female; the generation time was 47.390 days; the doubling time was 9.480 days; the intrinsic rate of increase (rm) was 0.073, and the finite rate of increase (l) was 1.076. The pre- dator population increased by 16.61 adult progeny per female per generation in the laboratory.

Competitive adsorption of zinc, cadmium, copper, and lead in three highly‐weathered Brazilian soils

Abstract: Equilibrium adsorption experiments on zinc (Zn), cadmium (Cd), copper (Cu), and lead (Pb) were conducted in three horizons of two Ultisols and one Oxisol with and without liming, from Vicosa‐MG (Brazil). Equilibrium solutions were applied as a “cocktail”; containing 700 mg L‐1 of Zn, 20 mg L#lb1 of Cd, 200 mg L‐1of Cu, and 300 mg L‐1 of Pb and its dilutions of 1:5 and 1:20. After shaking, the mixture was centrifuged, the supernatant collected and the pH and the concentrations of metals in the mixture were determined. Soil order, soil horizon, and liming had significant effects on the metal adsorption. Some important changes in the adsorption characteristics of the metals, especially in Zn and Cd, were observed due to competition between the different cations present in the solution. Also, desorption of Zn and Cd was observed with an increasing concentration of the solution. The adsorption data for Zn and Cd did not fit the linear, Langmuir, Freundlich, and Temkin isotherm equations for most situa...

Efeitos da fragmentação florestal sobre vespas e abelhas solitárias em uma área da Amazônia Central

Abstract: The effects of forest fragmentation on tree-hole nesting solitary wasps and bees were investigated at a site 90 km north of Manaus, Brazil. Wasp and bee faunas were monitored in continuous terra firme forest, forest fragments of 1, 10 and 100 ha, natural gaps in continuous forest and deforested areas. These habitats were studied in terms of abundance, richness, diversity and similarity. The wasps and bees were monitored monthly during June 1988 through June 1990 by means of a trap-nests technique. A total of 1529 nests of wasps of 24 species and 405 nests of bees of 14 species were collected. The number of species of wasps and bees varied little among the habitats. The genus Trypoxylon Latreille, 1796 (Sphecidae) accounted for 79% of wasp nests and Centris Fabricius, 1804 (Anthophoridae) for 56% of bee nests. Wasps showed an overall preference for cleared areas and fragments of 1 ha, whereas bees showed an overall preference for continuous forest and natural gaps. Nevertheless, some species of wasps showed a preference for nesting in continuous forest and some bees a preference for deforested areas. Species found in deforested areas also nested in small size forest fragments. This shows that species occurring predominantly in cleared areas can also colonize small forest fragments. The diversity of wasps and bees was greater in continuous forest. The composition of wasp and bee faunas of continuous forest was different from that of altered habitats. The similarity between the natural gaps and cleared areas was the smallest. The data suggest that the forest adapted bees are more sensitive to habitai fragmentation than the corresponding species of wasps. It is concluded that the preexisting cavity nesting solitary wasp and bee communities were altered by the forest fragmentation. However, it appears that at least in part, the natural variation in continuous forest could be responsible for the resulte obtained from this study.

Initial studies of mating disruption of the tomato moth, Tuta absoluta (Lepidoptera: Gelechiidae) using synthetic sex pheromone

Abstract: The potential of the synthetic major component of T. absoluta (Meyrick) sex pheromone for mating disruption was studied in small plots (0.01 hectares) with fresh-market tomato crop. The effects of the application of the sex pheromone 3E,8Z,11Z-14:Ac (from 0 to 80 g a.i./ha) were assessed on male orientation to pheromone baited traps, mating in cages and plant damage. The highest levels of interruption in male orientation (60-90%) were found in plots treated with 35 to 50 g/ha of sex pheromone. However, no treatment with pheromone was capable of significantly reducing the percentage of mined leaflets or bored fruits or the frequency of mating in cages compared to the control plots. The failure in mating disruption technique may be attributed to the composition of the synthetic pheromone, doses used, high pest population density, and mated female migration to the area treated.

A serious new wilt disease of Eucalyptus caused by Ceratocystis fimbriata in Central Africa

Abstract: Summary In a recent survey of Eucalyptus clones in the Republic of Congo, Central Africa, a serious wilt and die-back disease of two different hybrid clones was observed. Affected trees ranged in age from approximately 6 months to 4 years. Isolations from symptomatic plant material consistently yielded a Ceratocystis species. On the basis of morphology and sequence data this fungus was identified as Ceratocystis fimbriata, a well-known wilt and canker pathogen of many economically important plants. The Eucalyptus isolates were compared with other Ceratocystis spp. based on sequence data generated from the ITS and 5.8S region of the rRNA operon. The results confirmed the identity of the Ceratocystis isolates from Eucalyptus as C. fimbriata and showed that they group with other C. fimbriata isolates from Brazil, South Africa and Europe. Inoculations on young Eucalyptus plants were conducted in the greenhouse and all three of the Congolese isolates tested, produced typical lesions in the bark and xylem. This study represents the first report of C. fimbriata as a pathogen of Eucalyptus in Africa. This is a serious new disease that will require considerable study in order to ensure that losses, caused by C. fimbriata, do not continue.

Influence of a compacted loam subsoil layer on growth and yield of irrigated cotton in Southern Spain

Abstract: Subsoil compaction, which may occur naturally or be a consequence of machinery traffic, causes reductions in crop yields. The aim of this work was to characterize the effects of subsoil compaction on growth and yield of cotton (Gossypium hirsutum L.) under field conditions. Two field experiments were carried out in Cordoba, Spain, on an Eutric Fluvisol with loam texture. A treatment with a compacted layer (bulk density of 1.6–1.7 Mg m−3) at 0.2–0.4 m depth was compared with a control treatment with maximum bulk density of about 1.4 Mg m−3. Soil resistance to penetration was related to soil bulk density and water content. The compaction provoked reductions in root length (40% in 1996 and 33% in 1997), leaf area index (26% in 1996 and 12% in 1997), evapotranspiration (12% in 1996 and 7% in 1997) and seed cotton yield (28% in 1996 and 10% in 1997). Average resistance to penetration in the compacted layer was above 3 MPa (a threshold for cotton root growth according to the literature) but root growth was observed below this layer. It was speculated that spatial variation of soil bulk density and resistance and temporal variation of soil water content allowed the roots to find weaker path-ways to cross the compacted layer. The effect of the subsoil compaction on the soil characteristics and the root growth remained during the second experimental year but it was less pronounced on the above ground plant growth, development and yield. It was concluded that subsoil compaction influences significantly growth and yield of cotton, but successive cropping may alleviate the effects of the compaction.

Influence of the antibiotic timentin on plant regeneration of tomato (Lycopersicon esculentum Mill.) cultivars.

Abstract: Cotyledon explants of tomato (Lycopersicon esculentum Mill. cvs 'Santa Clara', 'Firme' mutant, 'IPA-5' and 'IPA-6') were excised from 8- to 10-day-old in vitro-grown seedlings. Four different shoot induction media supplemented with timentin (300 mg l–1) were screened. When cotyledon explants were cultured on MS-based medium with 1.0 mg l–1 zeatin plus 0.1 mg l–1 IAA and supplemented with timentin, higher regeneration frequencies and a greater number of elongated shoots were obtained. It was observed that timentin caused an increase in the morphogenesis of in vitro cotyledon explants of tomato cultivars. In two of three cultivars tested, rooting of shoots was positively influenced, both in the presence and absence of timentin in the rooting medium, among shoots regenerated from explants derived from timentin-supplemented medium. The results confirm those of a previous investigation on the beneficial effects of this class of antibiotics on tomato regeneration and, consequently, its reliability for use in the transformation of this species.

RAPD and SCAR Markers Linked to a Gene Conferring Resistance to Angular Leaf Spot in Common Bean

Abstract: Keywords: angular leaf spot; common bean; random amplified polymorphic DNA (RAPD); sequence-characterized amplified regions (SCAR); resistance

Influência da cobertura vegetal de inverno e da adubação orgânica e, ou, mineral sobre as propriedades físicas de uma Terra Roxa Estruturada

Abstract: O presente trabalho objetivou avaliar a influencia da cobertura vegetal de inverno, constituida de uma associacao de aveia preta (Avena strigosa Schreb) com nabo forrageiro (Raphanus sativus L.), da adubacao orgânica com esterco de aves, da adubacao orgânica e mineral e da adubacao mineral sobre propriedades fisicas do solo, numa Terra Roxa Estruturada do estado de Santa Catarina. As analises foram realizadas em amostras de solo coletadas em agosto de 1994 e janeiro de 1995, nas profundidades de 0-10, 10-20 e 20-30 cm, em um experimento iniciado em 1990. Verificou-se uma reducao na estabilidade de agregados maiores que 4,76 mm, quando se fez uso de adubacao orgânica, bem como aumento na estabilidade de agregados das classes de diâmetro 4,76 a 2,00 e 2,00 a 1,00 mm. Na camada de solo de 0-10 cm, observou-se que o adubo orgânico aumentou a macroporosidade e diminuiu a densidade do solo, enquanto a adubacao orgânica e mineral reduziu a macroporosidade e aumentou a microporosidade e a densidade do solo.

Inheritance of Angular Leaf Spot Resistance in Common Bean and Identification of a RAPD Marker Linked to a Resistance Gene

Abstract: Angular leaf spot, caused by Phaeoisariopsis griseola (Sacc.) Ferraris, is one of the major diseases affecting the common bean (Phaseolus vulgaris L.) in Brazil which can lead to severe yield losses. Previous studies demonstrated that cultivar MAR-2 was resistant to race 63.39 of P. griseola. The objective of this work was to characterize the resistance to angular leaf spot in MAR-2 in an F 2 population derived from the cross with Ruda (susceptible parent), and also to identify random amplified polymorphic DNA (RAPD) markers linked to the resistance gene. Cultivar MAR-2 was crossed with Ruda, a carioca-type cultivar susceptible to angular leaf spot, to determine the inheritance of resistance. The results demonstrated that a single dominant gene present in MAR-2 was responsible for the resistance to P. griseola, race 63.39. Resistant and susceptible DNA bulks from the F 2 population were constructed to identify RAPD markers linked to the resistance gene. Amplification with primer OPE-04 generated a 500-bp fragment which distinguished the resistant from the susceptible bulk populations. Co-segregation analysis of the entire population demonstrated that the RAPD marker was linked to the resistance gene at a distance of 5.8 Cm.

Produtividade e valor nutritivo do capim-elefante cv. Napier sob doses crescentes de nitrogênio e potássio

Abstract: Avaliaram-se os efeitos das adubacoes nitrogenada e potassica sobre o capim-elefante "Napier". Quatorze combinacoes entre N e K, de um fatorial incompleto de N e K, avaliados em sete doses de N (20, 50, 100, 200, 300, 350 e 380 kg/ha de N) e sete de K (16, 40, 80, 160, 240, 280 e 304 kg/ha de K), foram obtidas de acordo com a matriz Box Berard aumentada 3, com acrescimo de um ponto. Os tratamentos foram distribuidos em blocos ao acaso com tres repeticoes. A produtividade foi aumentada pelas adubacoes nitrogenada e potassica em 86%. A relacao lâmina/colmo e o teor de Mg2+ diminuiram com a adubacao potassica. Os teores de P e Ca2+ diminuiram com a adubacao nitrogenada, enquanto o teor de proteina bruta aumentou de maneira quadratica pelas adubacoes nitrogenada e potassica. O teor de K aumentou com a adubacao potassica e diminuiu com a nitrogenada. O nivel critico de potassio na planta foi 1,85 dag/kg na materia seca.

Fruit size, mineral composition and quality of trickle-irrigated tomatoes as affected by potassium rates

Abstract: Para determinar o efeito da fertirrigacao com K sobre o tamanho, a composicao mineral e a qualidade dos frutos do tomateiro, foi conduzido um experimento com aplicacao de seis doses de K, na forma de KCl, correspondendo a 0, 48,4, 118,6, 188,8, 259,0 e 399,4 kg ha-1, com quatro repeticoes, distribuidas no delineamento experimental em blocos casualizados. Foram observadas respostas quadraticas das producoes das classes de frutos graudo 2 (diâmetro > 60 mm), graudo 1 (56 a 60 mm) e graudo (52 a 56 mm) em relacao as doses de K aplicadas na adubacao. As producoes maximas de frutos de cada classe foram obtidas com as doses de K de 116, 190 e 233 kg ha-1, respectivamente. O conteudo de materia seca e os teores de P, S e Mg dos frutos nao foram influenciados pelas doses de K, mas os teores de nitrato e de potassio aumentaram com o aumento das doses. Os teores de vitamina C, solidos soluveis, licopeno e b-caroteno nao foram influenciados pelas doses de K; porem, os incrementos nas doses reduziram o pH e aumentaram o conteudo de acidos nos frutos.

Consumo e digestões totais e parciais em novilhos F1 Limousin x Nelore alimentados com dietas contendo cinco níveis de concentrado

Abstract: RESUMO - Um ensaio foi realizado com o objetivo de avaliar os efeitos de cinco niveis de concentrado nas racoes sobre o consumo e as digestibilidades aparentes totais e parciais de materia seca (MS), materia orgânica (MO), proteina bruta (PB), extrato etereo (EE), carboidratos totais (CHO), fibra em detergente neutro (FDN) e carboidratos nao-estruturais (CNE). Cinco novilhos F1 Limousin x Nelore fistulados no rumen, abomaso e ileo foram alimentados a vontade com dietas que continham 25,0; 37,5; 50,0; 62,5; e 75,0% de concentrado e distribuidos em delineamento quadrado latino 5 x 5. O oxido cromico foi usado como indicador externo, para as determinacoes das digestibilidades aparentes totais e parciais. A adicao de quantidades crescentes de concentrado a dieta produziu aumentos lineares nos consumos de MS, MO, CNE, PB, EE e NDT e reducao no consumo de FDN. As digestibilidades aparentes totais de MS, MO, PB, EE, CHO e CNE elevaram-se linearmente com o aumento dos niveis de concentrado da dieta. A digestibilidade aparente da PB no intestino delgado aumentou linearmente com a adicao de concentrados nas racoes. As digestibilidades aparentes da FDN no rumen e pos-rumen nao foram influenciadas pelos niveis de concentrado. Reducao nos niveis de FDN das racoes resultou em aumentos lineares do NDT e da digestibilidade aparente total da MS.

Flúor em chuva simulada: sintomatologia e efeitos sobre a estrutura foliar e o crescimento de plantas arbóreas

Abstract: Fluoride in simulated rain: symptomatology and effects on leaf structure and growth of wood plants). The objectives of this study was to characterize the effects of fluoride on seedlings and young plants of native woody species from Parque Estadual do Rio Doce (MG) and on the leaf blade structure of the most sensitive of the studied tree species. This work was carried out to gain information on diagnosing criteria for bioindication and to throw some light on the mechanisms of plant resistance and tolerance in order to assist in the revegetation programs of highly affected areas. The employed species were Gallesia gorazema Moq. (Phytolac- caceae), Genipa americana L. (Rubiaceae), Joannesia princeps Vell. (Euphorbiaceae), Peltophorum dubium (Spreng.) Taub. (Legu- minosae, Caesalpinioideae) and Spondias dulcis Forst. f. (Anarcadiaceae). Seedlings and young plants of those species were submitted to rain with dissolved fluoride (30 mg.L -1 ), during 20 min daily, for 10 consecutive days. Apical and marginal necrosis occurred in the leaf blades of all species just after the first simulated rain. Two days after treatment, S. dulcis, in the young plant stage, showed to be the most sensitive species by exhibiting large necrotic areas, while G. americana was the most resistant species. At the young plant stage, the species that accumulated more fluoride were also the most sensitive ones; such a relation was not observed in plants at the seedling stage. The pollutant at the level employed caused drastic alterations in the leaf blade of S. dulcis and also damaged all of its anatomical structure. The high susceptibility of S. dulcis to fluoride suggests that this species possess potential features to be employed as a bioindicator. However, for a better characterization of the responses of S. dulcis to fluoride and its usage in biomonitoring programs, more studies are required. RESUMO - (Fluor em chuva simulada: sintomatologia e efeitos sobre a estrutura foliar e o crescimento de plantas arboreas). Os objetivos deste trabalho foram: caracterizar os efeitos do fluor em especies arboreas nativas, nos estadios de plântula e muda; identificar injurias provocadas pelo fluor na estrutura da lâmina foliar da especie mais sensivel; fornecer subsidios para selecao de caracteristicas a serem utilizadas na bioindicacao; e contribuir com informacoes sobre a resistencia ou tolerância das plantas, visando ao reflorestamento de areas impactadas pela chuva com fluor. As especies analisadas foram Gallesia gorazema Moq. (Phytolaccaceae), Genipa americana L. (Rubiaceae), Joannesia princeps Vell. (Euphorbiaceae), Peltophorum dubium (Spreng.) Taub. (Leguminosae, Caesalpinioideae) e Spondias dulcis Forst. f. (Anacardiaceae). Plântulas e mudas dessas especies, provenientes do Parque Estadual do Rio Doce (MG), foram submetidas a 20 min diarios de chuva com fluor (30 mg.L -1 ), por 10 dias consecutivos. Necroses apicais e marginais foram observadas em todas as especies analisadas, logo apos a primeira chuva simulada. S. dulcis, no estadio de muda, foi a especie mais sensivel ao fluor, pois apresentou extensas necroses com apenas dois dias de tratamento, enquanto que G. americana foi a especie mais resistente. Nas mudas, as especies que acumularam mais fluor foram tambem as que apresentaram maior sensibilidade a esse poluente; essa relacao nao foi verificada nas plântulas. A concentracao de fluor utilizada promoveu alteracoes drasticas na lâmina foliar de S. dulcis com extensas areas necrosadas, danificando toda a sua estrutura anatomica. A sensibilidade ao fluor observada em S. dulcis indica que essa especie apresenta potencial para ser usada como bioindicadora. Entretanto, estudos detalhados serao necessarios para a melhor caracterizacao das respostas de S. dulcis ao fluor visando a sua utilizacao em programas de biomonitoramento ambiental.

Curva de lactação na raça Guzerá

Abstract: The objectives of this work were to identify the mathematical functions that better fitted the milk production of Guzera breed cows, to evaluate the effects of the environmental factors on the lactation curve format and to estimate the genetic parameters for the milk production and for the dependable components of the lactation curve format. A total of 1130 lactations from 583 Guzera breed cows, daughters of 165 bulls, with production over the period from 1983 to 1997 were used. The models y = a n e -cn, y = a - cn + ln (n), y=a -cn e y =a e-c n were the ones that best fitted the milk production of the cows. By the analysis of variance, it was observed that the effects of cow herd, calving year and cow age at calving influenced the total milk production, initial milk production and milk decline production rate characteristics. The coefficients of heritability and repeatability estimates were obtained by means of one and two characteristic analyses. The animal selection, based only on the of the lactation curve format, would be of low efficiency.