scholarly journals Saprophytic Survival of Ophiobolus Graminis on Various Hosts

1968 ◽  
Vol 21 (6) ◽  
pp. 1153 ◽  
Author(s):  
SC Chambers ◽  
NT Flentje
Keyword(s):  
Field Conditions ◽  
Lolium Rigidum ◽  
Laboratory Conditions ◽  
Hordeum Leporinum ◽  
Field And Laboratory Conditions

Survival of Ophiobolus graminis on artificially infected straw of several hosts was studied under field and laboratory conditions over a period of 24 weeks. Survival, estimated by percentage of straws containing viable hyphae of O. graminis, was greater on barley than on wheat, Hordeum leporinum, Lolium rigidum, and Vulpia myuros. Survival was higher under laboratory than summer field conditions, and in the field was greater at 1 than at 6 in. below the surface; survival was increased under laboratory conditions by nitrate enrichment of soil

Adsorption, dissipation, and movement of fluometuron in three southeastern United States soils

Weed Science ◽  
1997 ◽  
Vol 45 (1) ◽  
pp. 183-189 ◽  
Author(s):  
William T. Willian ◽  
Thomas C. Mueller ◽  
Robert M. Hayes ◽  
Charles E. Snipes ◽  
David C. Bridges
Keyword(s):  
United States ◽  
Organic Matter ◽  
Soil Profile ◽  
Soil Depth ◽  
Southeastern United States ◽  
Clay Content ◽  
Field Conditions ◽  
Laboratory Conditions ◽  
Controlled Conditions ◽  
Field And Laboratory Conditions

Fluometuron adsorption and dissipation under field and laboratory conditions, and distribution within the soil profile was determined in 3 soils from Tennessee, Mississippi, and Georgia that are representative of the cotton-growing regions of the southeastern United States. Fluometuron adsorption was correlated with organic matter, but not with clay content or soil pH. First-order kinetics explained fluometuron dissipation under field and controlled conditions (r2≥ 0.82). Field dissipation of fluometuron was slower under dry conditions. Fluometuron was not detected below 15 cm in the soil profile in any soil, and concentrations in the 8- to 15-cm soil zone were < 15 ppbw 112 d after treatment. Fluometuron dissipation was more rapid in soil from the 0- to 8-cm depth in Tennessee soil than in Mississippi soil under controlled conditions. Dissipation was more rapid under field conditions than under laboratory conditions at 2 of 3 locations. Fluometuron half-lives in soils from the 0- to 8-cm depth ranged from 9 to 28 d under field conditions and from 11 to 43 d in the laboratory. Fluometuron dissipation in soils from 30- to 45- and 60- to 90-cm depths was not different among soils, with half-lives ranging from 58 to 99 d under laboratory conditions. Fluometuron half-life was positively correlated with soil depth and inversely correlated with organic matter. These data indicate that organic matter, soil depth, and environmental conditions affect fluometuron dissipation.

scholarly journals Effectiveness of Bacillus thuringiensis Berliner var. kurstaki on the grape berry moth Lobesia botrana Den. and Shiff. (Lepidoptera, Tortricidae) under field and laboratory conditions in Crete

2017 ◽  
Vol 4 ◽  
pp. 31 ◽  
Author(s):  
Ν.Ε. Roditakis
Keyword(s):  
Bacillus Thuringiensis ◽  
Lobesia Botrana ◽  
Grape Berry ◽  
Egg Laying ◽  
Field Conditions ◽  
Egg Hatching ◽  
Laboratory Conditions ◽  
And Control ◽  
Trap Catches ◽  
Field And Laboratory Conditions

The effectiveness of Bacillus thuringiensis Berliner var. kurstaki (Dipel Abbot Lab.) against the grape berry moth (Lobesia botrana Den. & Shiff.) was evaluated under laboratory and field conditions. Under laboratory conditions (24±0.5°C, 55±5% r.h., 2,000 Lux, and 16 hours light daily) B. thuringiensis was compared to triflumuron and methomyl on egg hatching and shallow entries per grape berry. B. thuringiensis had no effect on egg hatching while methomyl and triflumuron had ovicidal action. Shallow entries per grape berry were 0.9-1, 0, 0 and 4.55 for B. thuringiensis, triflumuron, methomyl and control, respectively. Under field conditions, using as criteria for the timing of sprays: a. pheromone and food trap catches and b. visual counting of egg laying and a threshold of 20-30 eggs/100 grapes, two applications of B. thuringiensis at Kastelli Pediados in 1981 and four at Peza in 1982 were made both at the 2nd and 3rd flights. Its effectiveness was 96-100% and 92% at Kastelli Pediados and 73-75% at Peza.

scholarly journals ANÁLISE COMPARATIVA DA CARACTERIZAÇÃO FÍSICO –HÍDRICA DE UM LATOSSOLO VERMELHO DISTRÓFICO IN SITU E EM LABORATÓRIO

Irriga ◽  
2005 ◽  
Vol 10 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Polyanna Mara de Oliveira ◽  
Antônio Marciano da Silva ◽  
Gilberto Coelho ◽  
Ricardo Augusto da Silva
Keyword(s):  
Hydraulic Conductivity ◽  
Field Capacity ◽  
Field Conditions ◽  
Water Retention Curve ◽  
Moisture Determination ◽  
Internal Drainage ◽  
Retention Curve ◽  
Laboratory Conditions ◽  
Field And Laboratory Conditions

ANÁLISE COMPARATIVA DA CARACTERIZAÇÃO FÍSICO –HÍDRICA DE UM LATOSSOLO VERMELHO DISTRÓFICO IN SITU E EM LABORATÓRIO  Polyanna Mara de Oliveira; Antônio Marciano da Silva; Gilberto Coelho; Ricardo Augusto da SilvaDepartamento de Engenharia, Universidade Federal de Lavras ,Caixa Postal 37, CEP 37200-000, , Lavras, MG,  [email protected]  1 RESUMO Neste trabalho estudaram-se métodos para a estimativa da umidade representativa da capacidade de campo e da condutividade hidráulica não saturada para o Latossolo Vermelho Distrófico, trabalhando com dois métodos, o de perfil instantâneo (HILLEL et al., 1972) e o método empírico de Mualem (1976). Em laboratório foram realizadas a análise granulométrica, densidade do solo, porosidade (macro e microporosidade) e a curva característica de retenção, e em campo, determinaram-se a umidade na capacidade de campo e a condutividade hidráulica. Os resultados encontrados permitem afirmar que a caracterização físico-hídrica do solo em condições de campo mostrou-se mais precisa e confiável em relação às determinações de laboratório sendo que a estimativa da condutividade hidráulica mostrou-se mais consistente com outros atributos do solo e mais representativa da realidade do que aquela baseada em análises laboratoriais. Embora a metodologia de Mualem (1976) possa ser aplicada desde a umidade de saturação até o ponto de murcha permanente, a mesma não mostrou sensibilidade para registrar a influência da macroporosidade sobre a condutividade hidráulica do solo. A estimativa da umidade na capacidade de campo “in situ” ratifica também a melhor performance do método de campo em relação ao laboratorial. UNITERMOS: condutividade hidráulica, capacidade de campo, curva de retenção de água, drenagem interna do solo, atributos físicos do solo.  OLIVEIRA, P. M. de; SILVA, A. M. da; COELHO, G.; SILVA, R. A. COMPARATIVE ANALYSE OF THE PHYSICAL AND WATER CHARACTERIZATION IN FIELD AND LABORATORY CONDITIONS OF DISTROFIC RED LATOSSOL  2 ABSTRACT The aim of this work was to study methods to determine significant moisture for field capacity and non-saturated hydraulic conductivity in dystrophic latossol soil using two methods: internal drainage method (Hillel et al., 1972) and empiric method (Mualem, 1976). Granulometric analysis, soil density, porosity (macro and micro porosity) and characteristic retention curve were determined in laboratory; moisture for field capacity and hydraulic conductivity were determined in field conditions. The results showed that physical and hydraulic soil characterization in field conditions is more accurate and reliable than in lab conditions; hydraulic conductivity determination infield conditions was more consistent with other soil attributes and more realistic than the one based on laboratory conditions. Although Mualem’s method (1979) may be used for saturation moisture as well as for permanent internal drainage, it has not presented the same sensitivity to determine the influence of macro porosity on soil hydraulic conductivity. Moisture determination for field capacity under field conditions also corroborates better performance for field methods than laboratory ones.  KEYWORDS: hydraulic conductivity, field capacity, water retention curve, soil internal drainage, soil physical properties 

Norflurazon adsorption and dissipation in three southern soils

Weed Science ◽  
1997 ◽  
Vol 45 (2) ◽  
pp. 301-306 ◽  
Author(s):  
William T. Willian ◽  
Thomas C. Mueller ◽  
Robert M. Hayes ◽  
David C. Bridges ◽  
Charles E. Snipes
Keyword(s):  
Organic Matter ◽  
Soil Profile ◽  
Surface Soil ◽  
Field Conditions ◽  
Loamy Sand ◽  
Soil Horizon ◽  
Silt Loam ◽  
Laboratory Conditions ◽  
Soil Zone ◽  
Field And Laboratory Conditions

Norflurazon adsorption and dissipation under field and laboratory conditions, and distribution within the soil profile were determined in three soils representative of cotton-growing regions of the southeastern U.S. Norflurazon adsorption was greater in soil from 0 to 8 cm in a Lexington silt loam (Tennessee) and a Beulah silt loam (Mississippi) than in a Dothan loamy sand (Georgia). Adsorption was directly related to organic matter. Norflurazon degradation under controlled conditions in soil from 0 to 8 cm from each state was not different among locations, with half-lives ranging from 63 to 167 d. Degradation at 30 C in soil from the 30- to 45- and 60- to 90-cm depths was not different among locations, and was slower at the 60- to 90-cm depth than in surface soil. Norflurazon dissipation was more rapid under field conditions than under laboratory conditions, with half-lives ranging from 7 to 79 d in the 0- to 8-cm soil horizon. Dry field conditions slowed norflurazon dissipation. Norflurazon was not detected below 15 cm in the profile in any soil, and concentrations in the 8- to 15-cm soil zone were < 36 ppbw 112 d after treatment.

scholarly journals A laboratory and field condition comparison of life table parameters of Aphis gossypii Glover (Hemiptera: Aphididae)

2015 ◽  
Vol 55 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Behnaz Hosseini-Tabesh ◽  
Ahad Sahragard ◽  
Azadeh Karimi-Malati
Keyword(s):  
Population Dynamics ◽  
Relative Humidity ◽  
Life Table ◽  
Aphis Gossypii ◽  
Field Conditions ◽  
Life Table Parameters ◽  
Laboratory Conditions ◽  
Rate Of Increase ◽  
Aphis Gossypii Glover ◽  
Field And Laboratory Conditions

Abstract Life table studies are essential tools for understanding population dynamics. The life table parameters of Aphis gossypii Glover (Hemiptera: Aphididae) feeding on the host plant, Hibiscus syriacus L. were studied under laboratory (25±1°C and relative humidity of 65±5% and a photoperiod of 16L : 8D h) and field conditions (23-43°C, and relative humidity of 27-95%). The data were analysed using the age-stage, two-sex life table theory. The life table studies were started with 50 and 40 nymphs in laboratory and field conditions, respectively. Under laboratory conditions, A. gossypii reared on H. syriacus had a higher survival rate, fecundity, and longevity than those reared under field conditions. When reared under field conditions, A. gossypii had a longer nymphal developmental time, shorter adult longevity, and lower fecundity than those reared under laboratory conditions. The intrinsic rate of increase (r), net reproductive rate (R0), and the finite rate of increase (λ) under laboratory conditions, were higher than those obtained under field conditions. Nevertheless, there were no significant differences in the mean generation time T (days) between field and laboratory conditions. In the present study, the results clearly showed that life table parameters of A. gossypii were significantly different under field and laboratory conditions. These results could help us to understand the A. gossypii population dynamics under field conditions. The results could also help us make better management decisions for economically important crops

scholarly journals Chemical Composition and Insecticidal Potential of Six Essential Oils from Morocco against Dactylopius opuntiae (Cockerell) under Field and Laboratory Conditions

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1007
Author(s):  
Chaimae Ramdani ◽  
Karim El Fakhouri ◽  
Mohamed Sbaghi ◽  
Rachid Bouharroud ◽  
Rachid Boulamtat ◽  
...  
Keyword(s):  
Essential Oils ◽  
Insect Pest ◽  
Field Conditions ◽  
Toxic Activity ◽  
Laboratory Conditions ◽  
Adult Females ◽  
Prickly Pear Cactus ◽  
High Level ◽  
Field And Laboratory Conditions ◽  
Pear Cactus

The carmine cochineal Dactylopius opuntiae (Cockerell) is the major insect pest of the prickly-pear cactus Opuntia ficus-indica (L.) in Morocco. The present study investigated the insecticidal activities of six essential oils (EOs) against nymphs and adult females of D. opuntiae applied singly or in combination with a detergent under laboratory and field conditions. Under laboratory conditions, M. pulegium and O. vulgare L. essential oils showed a high level of insecticidal activity at 5%, with 98% and 92% females’ mortality, respectively, 5 days after treatments. The M. pulegium and O. vulgaris oils at 5% applied in combination with black soap at (60 g/L) induced the highest toxic activity on adult females, 100% and 96% at 5 days after treatments, respectively. Under field conditions, M. pulegium and O. vulgare oils at 5% in combination with black soap (60 g/L) showed the highest adult female mortalities with 96.33 and 92.56%, respectively, 7 days after the first application. The double application of M. pulegium oil at 5% significantly increased the mortality of adult females up to 91%, 5 days after the second spray. GC-MS analysis revealed that the most abundant constituent of M. pulegium and O. vulgare oils was pulegone (84.69%) and durenol (76.53%), respectively. These findings showed that the use of M. pulegium and O. vulgare in combination with black soap or in double sprays could be incorporated in the management package for the control of the wild cochineal D. opuntiae, as a safe and natural alternative to chemical insecticides.

Heavy metal depuration in flat tree oystersisognomon alatusunder field and laboratory conditions

2004 ◽  
Vol 86 (3) ◽  
pp. 171-179 ◽  
Author(s):  
Katayon Saed ◽  
Ahmad Ismail ◽  
Hishamuddin Omar ◽  
Misri Kusnan
Keyword(s):  
Heavy Metal ◽  
Laboratory Conditions ◽  
Field And Laboratory Conditions

scholarly journals Electrical conductivity of the seed soaking solution and soybean seedling emergence

2004 ◽  
Vol 61 (2) ◽  
pp. 164-168 ◽  
Author(s):  
Roberval Daiton Vieira ◽  
Angelo Scappa Neto ◽  
Sonia Regina Mudrovitsch de Bittencourt ◽  
Maristela Panobianco
Keyword(s):  
Electrical Conductivity ◽  
Water Content ◽  
Seedling Emergence ◽  
Soybean Seed ◽  
Accelerated Aging ◽  
Seed Vigor ◽  
Soybean Seedling ◽  
Seed Soaking ◽  
Laboratory Conditions ◽  
Field And Laboratory Conditions

Vigor of soybean [Glycine max (L.) Merrill] seeds can be evaluated by measuring the electrical conductivity (EC) of the seed soaking solution, which has shown a satisfactory relationship with field seedling emergence, but has not had aproper definition of range yet. This work studies the relationship between EC and soybean seedling emergence both in the field and laboratory conditions, using twenty two seed lots. Seed water content, standard germination and vigor (EC, accelerated aging and cold tests) were evaluated under laboratory conditions using -0.03; -0.20; -0.40 and -0.60 MPa matric potentials, and field seedling emergence was also observed. There was direct relationship between EC and field seedling emergence (FE). Under laboratory conditions, a decreasing relationship was found between EC and FE as water content in the substrate decreased. Relationships between these two parameters were also found when -0.03; -0.20 and -0.40 MPa matric potentials were used. EC tests can be used successfully to evaluate soybean seed vigor and identify lots with higher or lower field emergence potential.

scholarly journals Selección para calidad fisiológica de la semilla y rendimiento en líneas S2 derivadas de cuatro poblaciones tropicales de maíz (Zea mays L.)

2016 ◽  
Vol 7 (1) ◽  
pp. 58
Author(s):  
Enrique Navarro ◽  
Cristina Vega ◽  
Fernando Narváez ◽  
Hugo Córdova
Keyword(s):  
Genetic Variability ◽  
Grain Yield ◽  
Recurrent Selection ◽  
Zea Mays L ◽  
Agronomic Traits ◽  
Reciprocal Recurrent Selection ◽  
Laboratory Conditions ◽  
Flower Plant ◽  
Ear Height ◽  
Field And Laboratory Conditions

This study was carried out in 1993 to evaluate S2 lines from four maize tropical populations improved by reciprocal recurrent selection. These lines were evaluated under field and laboratory conditions, the latter one to determine physiology quality. The main goal was to measure genetic variability within and among populations for traits such as grain yield, vigor and germination and to select the best lines under field and laboratory conditions. The combined analysis of variance showed great genetic variability among the S2 lines within and among populations for grain yield, days to flower, plant and ear height, among others. The maximum genetic variability was observed on the lines from population 43 and pool 23 for most of the traits, although the latter showed a greater genetic variability for grain yield. Besides, it is important to mention that the above populations included the best genotypes for grain yield, germination and vigor. Taking into account the above mentionel agronomic traits, fifteen lines were selected; 2 belong to population 43* pool 20, 2 from pool 19* pool 23, 8 from population 43, and 3 from pool 23. These results confirm the genetic superiority of the lines from populations 43 and pool 23, so that these populations should be recommended for future genetic improvement by reciprocal recurrent procedures.

scholarly journals Analysis of Working Qualitative Parameters for No-Till Machines

2011 ◽  
Vol 68 (1) ◽  
Author(s):  
Ovidiu RANTA ◽  
Ioan DROCAS ◽  
Sorin STANILA ◽  
Adrian MOLNAR ◽  
Mircea Valentin MUNTEAN ◽  
...  
Keyword(s):  
Field Experiments ◽  
State Of The Art ◽  
Field Conditions ◽  
Laboratory Conditions ◽  
Experimental Teaching ◽  
No Till ◽  
Soil Bin ◽  
Teaching Facility

Autors was designed a system to modify the SPC romanian seeding machine for in order that it can be used for no-till technology. This machine was manufactured with the help of S.C. MECANICA M.A.R.I..U.S. S.A. in Cluj- Napoca and it was used in laboratory conditions in a state of the art soil bin of Hohenheim University, Stuttgart and in laboratory-field conditions. The field experiments were located on a plot of Experimental Teaching Facility of USAMV Cluj-Napoca, on aluviosol molic soil after SRTS – 200, in location Lunca Someşului Mic (Podişul Someşan) .

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