scholarly journals Codling moth, navel orangeworm studies show knowing location of pests in walnuts should help disrupt mating, egg laying

1993 ◽  
Vol 47 (3) ◽  
pp. 13-15 ◽  
Author(s):  
G. Steven Sibbett ◽  
Donald L. Flaherty ◽  
Kathleen M. Kelley ◽  
Richard Rice ◽  
John E. Dibble
1964 ◽  
Vol 96 (8) ◽  
pp. 1087-1093 ◽  
Author(s):  
G. G. Dustan

AbstractExperiments and observations on Oriental fruit moths in cages and in a peach orchard showed that both males and females may mate more than once. The maximum recorded number of matings was 7 for males and 5 for females. Mating usually occurred in the late afternoon and early evening during the daily flight and egg-laying period. Males seldom mated oftener than once in 24 hours and they transferred only one spermatophore to the female per mating. In cages, males mated approximately 1.4 times each when confined with equal numbers of females. Of the females taken in bait traps in a peach orchard, an average of 2.9% had not mated, 78.8% had mated once, 14.6% twice, and 3.7% more than twice. The mating behaviour of the Oriental fruit moth was shown to be similar to that of the codling moth.


2010 ◽  
Vol 101 (5) ◽  
pp. 499-504 ◽  
Author(s):  
H.Q. Thomas ◽  
F.G. Zalom ◽  
N.L. Nicola

AbstractBlattisocius keegani (Fox) is a predatory mite in the family Ascidae (Acari), noted for potential biological control of Coleopteran stored product pests. Performance of B. keegani on eggs of navel orangeworm, Amyelois transitella Walker (Lepidoptera: Pyralidae), was investigated. Mites completed development from egg to adult in 9.2±0.22 days at 25°C and 50–60% relative humidity, and in 6.33±0.29 days at 32.2°C, 30% relative humidity. Mites provisioned with three or five eggs consumed a median of 1.25 to 1.5 eggs, with a maximum of three eggs consumed over 24 h. Regression analyses indicated egg-laying by B. keegani was significantly correlated with the number of A. transitella eggs consumed, and female mites laid an average of 5.82±0.44 eggs over 72 h. Blattisocius keegani, developed on fresh and frozen eggs, laid significantly more eggs when provided with fresh eggs (F3,26=6.16, P=0.0026) and were able to develop on frozen Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as an alternative host. Mites were equally fecund when fed eggs stored at 0° or −20°C. Provisioning of adult moth bodies in addition to egg prey items increased mite fecundity, although it was demonstrated that B. keegani are phoretic on adult moths as well. The results are the first experimental evidence of B. keegani as a predator of Lepidopteran eggs, as a phoretic species, and of their potential for biological control of navel orangeworm.


2020 ◽  
Vol 45 (1) ◽  
Author(s):  
Robert A Van Steenwyk ◽  
Stephen R Peters-Collaer

2011 ◽  
Vol 39 (No. 4) ◽  
pp. 117-125 ◽  
Author(s):  
J. Stará ◽  
F. Kocourek

The efficacy of a CpGV-based preparation of Czech production against codling moth (CM) was tested in an experimental apple orchard at Prague-Ruzyně in 1998&ndash;2000. The influence of CpGV treatment on the reduction of CM population density and fruit injury was evaluated in comparison with teflubenzuron. Decline of CpGV efficacy in the orchard was tested in laboratory conditions on apples sampled at different terms after CpGV treatment. The rates of CpGV applied ranged from 0.5 to 1.00 &times; 10<sup>13&nbsp;</sup>granulles/ha, and the number of applications from 3 to 5 per year. The biological efficacy of CpGV to reduce the CM population density ranged from 75.5% to 96.0%, that of teflubenzuron from 90.8% to 97.5%, compared to the untreated control. The CpGV treatment was more efficacious in reducing the CM population density than in reducing fruit injury. The efficacy of CpGV decreased to 50% after 20, 10 and 11 d after treatment in 1998, 1999 and 2000, respectively. According to our results, a 10 d interval for CpGV treatments is recommended in case of further mass egg-laying by CM in the period between CpGV applications. &nbsp;


2019 ◽  
Author(s):  
Mireia Plaza ◽  
Alejandro Cantarero ◽  
Juan Moreno

Female mass in most altricial birds reaches its maximum during breeding at egg-laying, which coincides temporally with the fertile phase when extra-pair paternity (EPP) is determined. Higher mass at laying may have two different effects on EPP intensity. On the one hand, it would lead to increased wing loading (body mass/wing area), which may impair flight efficiency and thereby reduce female’s capacity to resist unwanted extra-pair male approaches (sexual conflict hypothesis). On the other hand, it would enhance female condition, favouring her capacity to evade mate-guarding and to search for extra-pair mates (female choice hypothesis). In both cases, higher female mass at laying may lead to enhanced EPP. To test this prediction, we reduced nest building effort by adding a completely constructed nest in an experimental group of female pied flycatchers (Ficedula hypoleuca). Our treatment caused an increase in mass and thereby wing loading and this was translated into a significantly higher EPP in the manipulated group compared with the control group as expected. There was also a significant negative relationship between EPP and laying date and the extent of the white wing patch, an index of female dominance. More body reserves at laying mean not only a higher potential fecundity but a higher level of EPP as well. This interaction had not previously received due attention but should be considered in future studies of avian breeding strategies.


2019 ◽  
Author(s):  
Gretchen F. Wagner ◽  
Emeline Mourocq ◽  
Michael Griesser

Predation of offspring is the main cause of reproductive failure in many species, and the mere fear of offspring predation shapes reproductive strategies. Yet, natural predation risk is ubiquitously variable and can be unpredictable. Consequently, the perceived prospect of predation early in a reproductive cycle may not reflect the actual risk to ensuing offspring. An increased variance in investment across offspring has been linked to breeding in unpredictable environments in several taxa, but has so far been overlooked as a maternal response to temporal variation in predation risk. Here, we experimentally increased the perceived risk of nest predation prior to egg-laying in seven bird species. Species with prolonged parent-offspring associations increased their intra-brood variation in egg, and subsequently offspring, size. High risk to offspring early in a reproductive cycle can favour a risk-spreading strategy particularly in species with the greatest opportunity to even out offspring quality after fledging.


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