FACTORS AFFECTING INFECTIVITY OF VAIRIMORPHA NECATRIX (MICROSPORIDIA: NOSEMATIDAE) IN TRICHOPLUSIA NI (LEPIDOPTERA: NOCTUIAE)

1981 ◽  
Vol 113 (2) ◽  
pp. 93-102 ◽  
Author(s):  
Wei Hsuang Chu ◽  
Robert P. Jaques
Keyword(s):  
Trichoplusia Ni ◽  
Cabbage Looper ◽  
Artificial Light ◽  
Disease Development ◽  
Optimum Temperature ◽  
Factors Affecting ◽  
Rate Of Development ◽  
Time To Death ◽  
Third Instar Larvae

AbstractIngested dosages of 10.9 and 16.5 spores of Vairimorpha necatrix (Kramer) 7 and 27 weeks old, respectively, killed 50% of third-instar larvae of the cabbage looper, Trichoplusia ni (Hübner). Time to death of 50% of larvae (LT50) decreased from 14 to 3 days with increases in dosage from 5 × 101 to 5 × 106 spores (2-week-old)/Iarva. The LT50 for 5 × 101 spores/larva increased from 14 to 25 days with storage of spores at 4°C for 2 and 93 weeks, respectively. Spores applied to soil lost little activity during cool weather but spores applied in summer were inactivated within 60 days. Desiccation or exposure to sunlight or artificial light inactivated the spores. Rate of development of disease was increased by feeding host larvae a diet containing increased proportions of casein or sucrose. The optimum temperature for disease development in T. ni was 25°C.

RELATIONSHIPS BETWEEN THE PARASITOID HYPOSOTER EXIGUAE AND THE CABBAGE LOOPER, TRICHOPLUSIA NI: THE EFFECT OF HOST AGE ON OVIPOSITIONAL RATE OF THE PARASITOID AND SUCCESSFUL PARASITISM

1975 ◽  
Vol 107 (7) ◽  
pp. 689-694 ◽  
Author(s):  
Zane Smilowitz ◽  
Gerard F. Iwantsch
Keyword(s):  
Trichoplusia Ni ◽  
Cabbage Looper ◽  
Host Age ◽  
Older Individuals ◽  
Percentage Parasitism ◽  
First Instar ◽  
Third Instar Larvae

AbstractThe effect of host age of the cabbage looper, Trichoplusia ni (Hübner), on ovipositional rate and successful parasitism by Hyposoter exiguae (Viereck), a solitary endoparasitoid was investigated. Success in parasitism of T. ni was correlated with host age. Successful parasitism of hosts exposed as first, second, or early third instar larvae, ranged from 83 to 88%. A decline in parasitism was observed for the remaining instars with a low of 27% for mid-fifth instar larvae.A different relationship between host age and successful parasitism was observed in tests where all five instars of the host were presented to the parasitoid simultaneously. Successful parasitism was highest among second and third instars, approximately 75% for both, and lowest for fifth and first instars, 10% and 30%, respectively. A significantly higher rate of mortality was found for first instar hosts.The ovipositional rate of H. exiguae was related to host age. The parasitoid deposited an average of 2.3 and 1.3 eggs per 24 h in first and second instar T. ni, respectively The number of eggs/host and degree of superparasitism declined in older individuals and differed statistically for each instar. The percentage parasitism differed statistically for all but first and second instar larvae.

Effects of host plant,Gossypium hirsutum L., on sexual attraction of cabbage looper moths,Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae)

1994 ◽  
Vol 20 (11) ◽  
pp. 2959-2974 ◽  
Author(s):  
P. J. Landolt ◽  
R. R. Heath ◽  
J. G. Millar ◽  
K. M. Davis-Hernandez ◽  
B. D. Dueben ◽  
...  
Keyword(s):  
Gossypium Hirsutum ◽  
Host Plant ◽  
Trichoplusia Ni ◽  
Sexual Attraction ◽  
Cabbage Looper ◽  
Gossypium Hirsutum L ◽  
Lepidoptera Noctuidae

scholarly journals Carrageenans, Sulphated Polysaccharides of Red Seaweeds, Differentially Affect Arabidopsis thaliana Resistance to Trichoplusia ni (Cabbage Looper)

PLoS ONE ◽  
2011 ◽  
Vol 6 (10) ◽  
pp. e26834 ◽  
Author(s):  
Jatinder S. Sangha ◽  
Wajahatullah Khan ◽  
Xiuhong Ji ◽  
Junzeng Zhang ◽  
Aaron A. S. Mills ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Trichoplusia Ni ◽  
Cabbage Looper ◽  
Sulphated Polysaccharides ◽  
Red Seaweeds

STUDIES ON THE SEEDLING DISEASE OF BARLEY CAUSED BY HELMINTHOSPORIUM SATIVUM P.K. & B.

1956 ◽  
Vol 34 (4) ◽  
pp. 653-673 ◽  
Author(s):  
R. A. Ludwig ◽  
R. V. Clark ◽  
J. B. Julien ◽  
D. B. Robinson
Keyword(s):  
Disease Incidence ◽  
Infested Soil ◽  
Disease Development ◽  
Toxic Activity ◽  
Factors Affecting ◽  
Seedling Disease ◽  
Nutrient Salt ◽  
Helminthosporium Sativum ◽  
Treatment Comparisons

A standard sand – cornmeal – nutrient salt medium, for use in the production of artificial inoculum of Helminthosporium sativum, is described. This inoculum induces uniform plant disease development when thoroughly incorporated with the planting soil. The results presented clearly demonstrate the necessity of using a series of infestation levels in studies of factors affecting disease development in artificially infested soil. It is shown that considerable reliance can be placed on treatment comparisons within an experiment but that comparisons between experiments are much less accurate. The role of a toxin (or toxins) in disease development in barley seedlings has been demonstrated. The toxic activity was found to be distinct from that frequently encountered on addition of organic matter to soil. Results obtained suggest that toxin adsorption by the soil may play an important role in reducing disease incidence and severity.

scholarly journals Cellular distribution of a high-affinity glutamate transporter in the nervous system of the cabbage looperTrichoplusia ni

2002 ◽  
Vol 205 (17) ◽  
pp. 2605-2613 ◽  
Author(s):  
Richard B. Gardiner ◽  
Kyrre Ullensvang ◽  
Niels C. Danbolt ◽  
Stanley Caveney ◽  
B. Cameron Donly
Keyword(s):  
Nervous System ◽  
Glial Cells ◽  
Trichoplusia Ni ◽  
Neuromuscular Junctions ◽  
Glutamate Transporter ◽  
Extracellular Fluid ◽  
Sensory Nerves ◽  
Cabbage Looper ◽  
Microscopical Examination ◽  
High Affinity

SUMMARYGlutamate functions as a neurotransmitter in the central nervous system(CNS) and neuromuscular junctions in insects. High-affinity glutamate transporters are responsible for keeping the resting levels of excitatory amino acids below the synaptic activation threshold by removing them from the extracellular fluid, thereby preventing them from reaching toxic levels. Peptides representing the N- and C-terminal regions of a glutamate transporter cloned from the cabbage looper caterpillar (Trichoplusia ni) were synthesized and used to generate polyclonal antibodies. The antibodies produced immunohistochemical staining in both muscular and nervous system T. ni tissues. Neuromuscular junctions in the skeletal muscles produced the most intense labelling, but no visceral muscle or sensory nerves were labelled. In the CNS, the neuropile of the ganglia, but not the connectives, gave a diffuse staining. Electron microscopical examination of ganglia and neuromuscular junctions showed that the plasma membrane of glial cells, but not that of neurons was labelled, in agreement with the notion that most of the glutamate uptake sites in this insect are in glial cells.

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