scholarly journals Relationship between Adult Pheromone Trap Catches and Injury in Soybean Leaves by Young Larvae of Spodoptera litura F. (Lepidoptera: Noctuidae).

2003 ◽  
Vol 47 (4) ◽  
pp. 137-141 ◽  
Author(s):  
Shin-ichirou Syobu ◽  
Hatsuko Mikuriya ◽  
Tomoya Kondou

1976 ◽  
Vol 66 (2) ◽  
pp. 279-300 ◽  
Author(s):  
R. J. Marks

AbstractThe synthetic sex pheromone (dicastalure) of the red bollworm of cotton, Diparopsis castanea Hmps., in Central and Southern Africa, and an inhibitor of male sexual attraction (trans-9-dodecenyl acetate,=IIA), were used in an enclosed 0·2 ha cotton field-cage to reduce successful female matings. Over one month dicastalure at 21·0 and 42·3 g/ha produced average reductions in mating of 47·9% and 72·5% respectively and 37·9 g IIA/ha produced an overall reduction in mating of 71·5%, or 79·5% in released moth populations, over the same period. The proportion of virgin females present in disruption situations was significantly greater than in untreated populations and was density-independent for moth populations of up to 2 200/ha. The proportion of fertile eggs in disruption situations was correspondingly reduced to 30·2% from an average of 67·9% in control cycles. Reduction in sex pheromone trap catches is an unsatisfactory indicator of the extent to which males are prevented from inseminating females and considerably over-estimates the true degree of disruption. This is the first time that a naturally occurring inhibitor has been used successfully to disrupt mating in a field population of insects and it indicates the potential of the method for the control of high density pest populations in cotton. However, use of polyethylene dispensing mechanisms similar to those used in the field-cage disruption experiments would be unsuitable as a practical method of dispensing behaviour modifying chemicals and it is suggested that, for suitably controlled release of such chemicals, currently available microencapsulation technology offers the best prospects.



2021 ◽  
Vol 21 (1) ◽  
pp. 68-75
Author(s):  
N. CHATTOPADHYAY ◽  
R. BALASUBRAMANIAM ◽  
S.D. ATTRI ◽  
KAMALJEET RAY ◽  
GRACY JOHN ◽  
...  

A study on the effect of weather parameters on the the population dynamics of Spodoptera litura (S.litura) in soybean and cotton during kharif season using six years pest data (pheromone trap catches) at Niphad and Rahuri in Maharashtra showed that rainfall two weeks prior, Tmax and Tmin during the week of incidence signifiantly contributed towards the occurrence of S.litura in soybean. Maximum temperature and morning humidity during the week and one week prior were found to be favourable for the incidence of S. litura in cotton. Temperature (maximum: 26-27°C & minimum: 21-22°C), morning relative humidity (above 90%) and rainfall during one week prior were found to be congenial weather parameters for the outbreak of the pest in soybean. Similarly, maximum temperature around 32-33°C, minimum temperature around 22-23°C, morning relative humidity around 90 per cent, sunshine hours about 4 hrs day-1 and rainfall during the previous 2 weeks favoured heavy incidence of S.litura in cotton crop during flowering to boll formation stages. It is also shown how the incidence of S.litura in soybean and cotton can be predicted well in advance using the observed relationship of the pest with weather parameters as well as weather forecast.



Author(s):  
S. Ramesh Babu ◽  
Prahlad Kumar Meena ◽  
Ramgopal Dudwal

A study was carried out to find out the effect of various weather parameters on the occurrence of major defoliators in soybean crop. Semilooper larval population was recorded late July/early August and their peak activity observed during 33-34, 33-36 and 37-39 standard weeks, in 2012, 2013 and 2014, respectively. Among the weather factors, morning relative humidity showed significant (r=0.954) and positively, highly influence on the larval population per mrl whereas evening humidity (r=-0.644) and sunshine hrs (r=-0.367) negatively and significantly influence the larval population per mrl. The various weather parameters significantly caused 92 per cent variations in larval population per mrl. The moth catches of Spodoptera litura increased from late-August to late-September and this trend was almost similar in different kharif seasons observed. Larval population of S. litura positively correlated with pheromone trap catches during 2014.



1991 ◽  
Vol 123 (2) ◽  
pp. 271-281 ◽  
Author(s):  
M.A. Latheef ◽  
J.A. Witz ◽  
J.D. Lopez

AbstractRelationships among catches of corn earworm moths, Helicoverpa (= Heliothis) zea (Boddie), in pheromone traps, numbers of corn earworm eggs, and corn ears with fresh silks were investigated in eight corn fields during a 2-year period in Brazos River Valley, Texas. Cross-correlation analysis indicated that the catches of corn earworm moths in pheromone traps were closely associated with egg numbers in seven of eight fields with a time differential varying between −1 to +2 days. Cross-correlation peaks for new silks versus eggs occurred with time differentials being mostly positive, indicating that corn earworm egg numbers reached a maximum after corn produced large numbers of fresh silks on ears.There was a weak but significant linear relationship between egg numbers and corn earworm catches in pheromone traps when corn was in the whorl stage of growth. A stepwise regression model of the form: log (eggs/ha + 1) = 3.71 + 0.22*log(S + 1)*log(T + 1) − 0.3*log(S + 1), where S = numbers of corn ears with new silks per hectare, and T = mean corn earworm moths per trap, explained 52.5% of the variance. These results emphasize the mediating effects of fresh silks on corn earworm oviposition on corn.



2018 ◽  
Vol 29 (5) ◽  
pp. 215-219
Author(s):  
Chipabika Gilson ◽  
Gonzalez Francisco ◽  
Georgina V. Bingham ◽  
Mathews Matimelo

Food Security is an issue that will impact everyone by 2050 and it is projected there will be a global crisis unless action is taken. Currently the fall army worm (FAW), Spodoptera frugiperda, is a new pest to the Sub-Saharan region and the outbreaks over the past two years have been devastating. A promising novel technology is the combination of a pheromone lure from ChemTica Internacional S.A. and yellow long-lasting insecticide treated ZeroFly Screen from Vestergaard SA. To test this technology, we compared the attraction and mortality of traps made of old soda bottles in five different sites of Zambia with maize and wheat crops. Besides the attraction of the pheromone-baited traps we also compared the effect of the colour of the insecticidal net, between black and yellow screens. Our results showed that in all sites there were significant differences in trap catches between lure baited and non-baited traps. A total of 1129 FAW adults were trapped, of which 51.20% were from baited traps with the yellow long-lasting insecticide treated screen, 41.45% from traps baited and the black long-lasting insecticide treated screen and 7.35% from trap without lure or the insecticide treated screen. The trap with yellow insecticide treated screen was able to trap 110 more FAW than the black treated screen and the control. Significant differences were also observed in number of moths caught from each location and district. The highest catches were recorded from wheat crops at Zambia National Service (ZNS) Farm in Chongwe and Chaloshi farm in Chisamba districts, respectively, whilst the lowest catch was recorded in a maize field at Tugama farm in Chilanga district. It was also noticed that the pheromone used is specific to FAW as no other insects were recorded in all the sites. Therefore, the pheromone lure from ChemTica and the yellow long lasting insecticide treated screen from Vestergaard SA can be used in the integrated pest management of FAW in Zambia in both, maize and wheat, these complimentary methods include but are not limited to; the use of Biopesticides – fungal, viral or bacteria based products such as Metarhizium anisopliae or bacteria-based Bacillus thuringiensis that have proven effective against fall armyworm and have been used to control it in the US and Brazil.



2021 ◽  
Vol 45 (1) ◽  
pp. 81-85
Author(s):  
M. Pazhanisamy ◽  
V. Sathyaseelan ◽  
M. Senthilkumar






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