THE CONSUMPTION OF EUPHORBIA CYPARISSIAS (EUPHORBIACEAE) BY LARVAE OF CELERIO EUPHORBIAE (LEPIDOPTERA: SPHINGIDAE)

1971 ◽  
Vol 103 (1) ◽  
pp. 59-66 ◽  
Author(s):  
T. R. New
Keyword(s):  
Energy Budget ◽  
Preliminary Data ◽  
Dry Weight ◽  
Field Conditions ◽  
Close Similarity ◽  
Feeding Experiments ◽  
Laboratory Results ◽  
Infested Site ◽  
Euphorbia Cyparissias

AbstractLaboratory feeding experiments on Celerio euphorbiae (L.) showed that each larva consumed about 2.7 g dry weight of Euphorbia cyparissias L. Laboratory-reared and field-collected larvae produced pupae of similar weights and the close similarity between the fresh and dry weights of control-fed larvae and larvae allowed to feed freely indicates that laboratory results are readily extrapolated to field conditions. On one infested site, at Braeside, Ont., the amount of spurge foliage was measured and the density of larvae needed to graze it fully was estimated at 14/m2 completing development. Preliminary data on an energy budget of the larva are discussed in relation to possible damage to the plant.

scholarly journals Application of Bio-Friendly Formulations of Chitinase-Producing Streptomyces cellulosae Actino 48 for Controlling Peanut Soil-Borne Diseases Caused by Sclerotium rolfsii

2021 ◽  
Vol 7 (3) ◽  
pp. 167
Author(s):  
Gaber Abo-Zaid ◽  
Ahmed Abdelkhalek ◽  
Saleh Matar ◽  
Mai Darwish ◽  
Muhammad Abdel-Gayed
Keyword(s):  
Open Field ◽  
Biocontrol Agent ◽  
Sclerotium Rolfsii ◽  
Dry Weight ◽  
Culture Broth ◽  
Field Conditions ◽  
Damping Off ◽  
Mycelium Growth ◽  
Particle Size Analyzer ◽  
Cell Pellet

Of ten actinobacterial isolates, Streptomyces cellulosae Actino 48 exhibited the strongest suppression of Sclerotium rolfsii mycelium growth and the highest chitinase enzyme production (49.2 U L−1 min−1). The interaction between Actino 48 and S. rolfsii was studied by scanning electron microscope (SEM), which revealed many abnormalities, malformations, and injuries of the hypha, with large loss of S. rolfsii mycelia density and mass. Three talc-based formulations with culture broth, cell-free supernatant, and cell pellet suspension of chitinase-producing Actino 48 were characterized using SEM, Fourier transform infrared spectroscopy (FTIR), and a particle size analyzer. All formulations were evaluated as biocontrol agents for reducing damping-off, root rot, and pods rot diseases of peanut caused by S. rolfsii under greenhouse and open-field conditions. The talc-based culture broth formulation was the most effective soil treatment, which decreased the percentage of peanut diseases under greenhouse and open-field conditions during two successive seasons. The culture broth formulation showed the highest increase in the dry weight of peanut shoots, root systems, and yielded pods. The transcriptional levels of three defense-related genes (PR-1, PR-3, and POD) were elevated in the culture broth formulation treatment compared with other formulations. Subsequently, the bio-friendly talc-based culture broth formulation of chitinase-producing Actino 48 could potentially be used as a biocontrol agent for controlling peanut soil-borne diseases caused by S. rolfsii.

scholarly journals Effects of Bacillus thuringiensis HC-2 Combined with Biochar on the Growth and Cd and Pb Accumulation of Radish in a Heavy Metal-Contaminated Farmland under Field Conditions

2019 ◽  
Vol 16 (19) ◽  
pp. 3676 ◽  
Author(s):  
Zigang Li ◽  
Peng Wang ◽  
Xiaoyu Yue ◽  
Jingtao Wang ◽  
Baozeng Ren ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Bacillus Thuringiensis ◽  
Organic Matter Content ◽  
Dry Weight ◽  
Underlying Mechanism ◽  
Water Soluble ◽  
Field Conditions ◽  
Resistant Bacteria ◽  
Culture Solution ◽  
Rhizosphere Soils

The objective of this study was to explore the effect of heavy metal-resistant bacteria and biochar (BC) on reducing heavy metal accumulation in vegetables and the underlying mechanism. We tested Bacillus thuringiensis HC-2, BC, and BC+HC-2 for their ability to immobilize Cd and Pb in culture solution. We also studied the effects of these treatments on the dry weight and Cd and Pb uptake of radish in metal-contaminated soils under field conditions and the underlying mechanism. Treatment with HC-2, BC, and BC+HC-2 significantly reduced the water-soluble Cd (34–56%) and Pb (31–54%) concentrations and increased the pH and NH4+ concentration in solution compared with their vales in a control. These treatments significantly increased the dry weight of radish roots (18.4–22.8%) and leaves (37.8–39.9%) and decreased Cd (28–94%) and Pb (22–63%) content in the radish roots compared with the control. Treatment with HC-2, BC, and BC+HC-2 also significantly increased the pH, organic matter content, NH4+ content, and NH4+/NO3− ratio of rhizosphere soils, and decreased the DTPA-extractable Cd (37–58%) and Pb (26–42%) contents in rhizosphere soils of radish. Furthermore, BC+HC-2 had higher ability than the other two treatments to protect radish against Cd and Pb toxicity and increased radish biomass. Therefore, Bacillus thuringiensis HC-2 combined with biochar can ensure vegetable safety in situ for the bioremediation of heavy metal-polluted farmland.

Recent Advances in Barite Sag Technology

2002 ◽  
Author(s):  
William M. Dye ◽  
Gregory A. Mullen ◽  
Bruce R. Ewen
Keyword(s):  
Laboratory Tests ◽  
Annular Flow ◽  
Field Conditions ◽  
Financial Impact ◽  
Poor Correlation ◽  
Flow Loop ◽  
Shear Rates ◽  
Laboratory Results ◽  
Static Conditions ◽  
Proper Consideration

The occurrence of barite sag is a well recognized but poorly understood phenomenon in the drilling industry. Industry experts have offered a variety of measuring parameters, based upon empirical data, that only partially correlate with the occurrence of barite sag. The industry’s lack of understanding of the mechanisms and types of barite sag generally result in a poor correlation between laboratory results and field observations of barite sag. The financial impact of barite sag on drilling costs, usually resulting from rig-time lost while circulating and conditioning the mud system, is not trivial. There are reported incidences where recurring barite sag problems have resulted in the loss of drilling projects. The accuracy and relevance of technology utilized to manage barite sag can help reduce drilling costs. In the field barite sag frequently occurs in deviated wells where pipe eccentricity creates conditions conducive to dynamic sag. With the exception of a flow loop, laboratory tests do not simulate field conditions. Historically, laboratory tests characterize density variations arising from a vertical fluid column as static or dynamic sag without proper consideration to angle, pipe eccentricity, annular shear rates and annular flow. This paper reviews traditional and newly-emerging barite sag technology and compares their ability to predict barite sag potential. This potential will be determined under dynamic and static conditions in a sophisticated flow loop configured to match certain field conditions.

MORPHOLOGICAL DEVELOPMENT OF TWO ALFALFA CULTIVARS UNDER VARIOUS HARVESTING SCHEDULES

1974 ◽  
Vol 54 (1) ◽  
pp. 79-87 ◽  
Author(s):  
Y. SINGH ◽  
J. E. WINCH
Keyword(s):  
Growth Rates ◽  
Dry Weight ◽  
Growing Season ◽  
Field Conditions ◽  
Morphological Development

Two alfalfa cultivars grown under field conditions were harvested at different stages of maturity during the growing season of 1969. The number of buds and stems that originated from various locations on the plant and the dry weight of the stems were recorded periodically. The pattern of regrowth was the same for both cultivars. During regrowth, following all stages of harvest, many buds that developed early failed to produce mature stems. Uncut alfalfa produced a second crop of regrowth stems from the bases of stems that formed the first growth. After each harvest regrowth stems originated mainly from the stubble of the most recently harvested stems. Yield reductions occurring in successive regrowths of each harvest schedule were due mainly to the production of smaller stems. Increased growth rates following more mature stages of cutting resulted mainly from faster elongation of stems developing from larger buds. The implications of these findings with respect to the breeding of alfalfa are discussed.

Variations in morphine, codeine and thebaine in the capsules of Papaver somniferum L. during maturation

1980 ◽  
Vol 31 (2) ◽  
pp. 313 ◽  
Author(s):  
PJ Hofman ◽  
RC Menary
Keyword(s):  
Relative Humidity ◽  
Fungal Growth ◽  
Dry Weight ◽  
Papaver Somniferum ◽  
Rapid Decrease ◽  
Field Conditions ◽  
Rapid Loss ◽  
Full Bloom ◽  
High Rainfall ◽  
Morphine Concentration

During the 1978-79 season, changes in the straw from a commercial and glasshouse-grown crop of Papaver somniferum L. were monitored. The percentage morphine and codeine reached their maximum values of 1.57 % and 0.10% respectively 5 weeks after full bloom under field conditions. Their contents changed little until the 11th week; thereafter losses of 35% and 32% in the morphine and codeine concentrations occurred over a 2 week period. This coincided with comparatively high rainfall and relative humidity, which permitted heavy fungal growth and a 28% decrease in the dry weight per sample of straw. There was a rapid decrease in thebaine concentration during the second week after full bloom, followed by a more gradual decrease up till 13 weeks after full bloom. A total loss of 58 % was recorded over the 13 week period, but there was no rapid loss during the 11-13 week period. Under glasshouse conditions morphine and codeine concentrations increased until the eighth and seventh weeks after full bloom respectively. The morphine concentration after this period showed little change, while that of codeine varied slightly. Their maximum detected concentrations were 1 .89 % and 0.16 % respectively. The thebaine concentration decreased rapidly during the first 5 weeks after full bloom from its highest detected value of 0.59% at week 2.

The Uptake and Accumulation of Zinc and Copper From Solution by two Species of Talitrid Amphipods (Crustacea)

1991 ◽  
Vol 71 (4) ◽  
pp. 811-826 ◽  
Author(s):  
J. M. Weeks ◽  
P. S. Rainbow
Keyword(s):  
Food Source ◽  
Metal Accumulation ◽  
Sea Water ◽  
Zinc Uptake ◽  
Field Conditions ◽  
Copper And Zinc ◽  
Uptake Rates ◽  
Laboratory Results

The exposure of two species of talitrid amphipods (Orchestia gammarellus and Orchestia mediterranea) to a range of zinc and copper concentrations in solution has enabled the categorization of the mode of metal accumulation adopted by these supralittoral amphipods. Both species showed net accumulation of dissolved zinc and copper at all experimental exposures between 20 and 1000 μig Zng 1 and 13 and 1000 μg Cu 1 in artificial sea-water. Studies using Zn have shown that the zinc uptake rates of both species (0·430 μg Zn g d, SE 0·032 and 0·408 µg Zn g d, SE 0·073 for O. gammarellus and O. mediterranea respectively at 10°C in 31·6 μg Zn 1) are not significantly different, and are low in comparison with other crustaceans. Laboratory results are related to field conditions, and it is concluded that Firth of Clyde O. gammarellus are more dependent upon a food source in order to meet both their copper and zinc requirements than are O. mediterranea which are able to obtain sufficient metabolic copper from solution. The use of talitrid amphipods in zinc and copper biomonitoring programmes is also discussed.

Resistance of standing milkvetch (Astragalus adsurgens) varieties to Embellisia astragali

2012 ◽  
Vol 63 (4) ◽  
pp. 351 ◽  
Author(s):  
B. H. Yu ◽  
Z. B. Nan ◽  
Y. Z. Li ◽  
H. L. Lin
Keyword(s):  
Disease Severity ◽  
Field Experiments ◽  
Agronomic Traits ◽  
Disease Incidence ◽  
Dry Weight ◽  
Severity Index ◽  
Field Conditions ◽  
Disease Severity Index ◽  
Greenhouse Experiments ◽  
Astragalus Adsurgens

Yellow stunt and root rot caused by Embellisia astragali are major factors contributing to declining yields of standing milkvetch (Astragalus adsurgens). The resistance of ten varieties of standing milkvetch to E. astragali was evaluated under laboratory, greenhouse, and field conditions. Seed germination/emergence, shoot and root length, plant dry weight, disease incidence, mortality, and disease severity index were monitored. The results show that Shanxi and Zhongsha No. 1 varieties had the best agronomic traits and lowest levels of disease in all experiments, while the varieties Neimeng and Ningxia had the highest susceptibility to disease. Germination/emergence differed significantly (P < 0.05) between varieties after inoculation, and compared with the control, germination/emergence of inoculated treatments of nine varieties decreased on average by 1.5% in laboratory experiments and by 4.1% in greenhouse experiments at 15 days after inoculation. Inoculation reduced shoot length by an average of 24.4% and 41.5% (P < 0.05) in laboratory and greenhouse experiments, respectively, in six of ten varieties. All varieties showed significantly (P < 0.05) lower plant dry weight following inoculation, with reductions ranging from 0.3 to 0.6 mg in the laboratory and from 82.6 to 149.4 mg in the greenhouse. Resistance to the pathogen was evaluated on the basis of disease incidence, a disease severity index (DSI), and mortality; varieties showing different resistance were grouped using cluster analysis. There were significant correlations between the results of laboratory and greenhouse experiments (r = 0.79; P < 0.01) and between greenhouse and field experiments (r = 0.83; P < 0.01) across all varieties. Multiple regression analysis between laboratory/greenhouse and field experiments on DSI suggested that screening in the laboratory/greenhouse could be an alternative method of rapidly estimating DSI under field conditions.

scholarly journals The Effect of Ammonium Nitrate Ratio and Support Types on the NPK Uptake and Growth of Black Pepper (Piper nigrum L.) in Field Conditions

Poljoprivreda ◽  
2021 ◽  
Vol 27 (2) ◽  
pp. 25-33
Author(s):  
Issukindarsyah Issukindarsyah ◽  
◽  
Endang Sulistyaningsih ◽  
DidikIndradewa Indradewa ◽  
Eka Tarwaca Susila Putra
Keyword(s):  
Plant Growth ◽  
Block Design ◽  
Dry Weight ◽  
Black Pepper ◽  
N Fertilizer ◽  
Field Conditions ◽  
Piper Nigrum ◽  
Pepper Plant ◽  
Randomized Block Design ◽  
Npk Uptake

The study’s objective was to determine the effect of the NO3-: NH4+ratio and types of support on NPK uptake and pepper plant growth in field conditions. The study used a completely randomized block design with three replications. The first factor was the type of support, being the deadwood and living supports in the form of Gliricidia sp. and Ceiba pentandra. The second factor was the ratio of N fertilizer forms, which were 100% NO3-, 100% NH4+, 50% NO3-:50% NH4+, 75% NO3-:25% NH4+ and 25% NO3-:75% NH4+. The results have demonstrated that the uptake of N, P, and K, as well as the plant growth, were not affected by the interaction of the N fertilizer form ratio with the types of support. In field conditions, the black pepper prefers the N fertilizer in the form of 50% NO3-:50% NH4+. The pepper plants that were given N fertilizer in a combination of 50% NO3-:50% NH4+ have demonstrated an N, P, and K uptake, and morphology and plant dry weight were higher than the ratio of other forms of N fertilizers.

scholarly journals Using energy budget data to assess the most damaging life-stage of an agricultural pest Mocis latipes (Guenèe, 1982) (Lepidoptera - Noctuidae)

2010 ◽  
Vol 70 (3) ◽  
pp. 459-463 ◽  
Author(s):  
MJT. Assunção-Albuquerque ◽  
MC. Peso-Aguiar ◽  
FS. Albuquerque
Keyword(s):  
Larval Development ◽  
Energy Budget ◽  
Plant Biomass ◽  
Life Stage ◽  
Larval Growth ◽  
Dry Weight ◽  
Growth Efficiency ◽  
Economic Damage ◽  
Gross Growth Efficiency ◽  
Mocis Latipes

There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8% of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6%. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.

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