摘要:

Laboratory studies of effects of temperature and adult density (10 females or 50 females per 250 cm2phloem ofUlmus AmericanaL.) on maternal gallery construction and oviposition byScolytus multistriatus(Marsham) indicated that response of adult beetles at 25 and 30°C was similar. At the higher density, maternal galleries were shorter (20 mm) and there were fewer egg niches per unit length of gallery (1.8/mm); at the lower density, maternal galleries averaged 23 mm and there were 2.5 egg niches per mm of gallery. Length of the egg-free portion of the maternal gallery was similar at both densities.

ISSN:0046-225X    

DOI:10.1093/ee/14.5.641

出版商:Oxford University Press    

年代:1985

数据来源: OUP

摘要:

When used in a pest control decision-making context, protocols for obtaining sample information on insect numbers can be evaluated via three properties: the operating characteristic (OC), the average sample number (ASN), and the availability of methods for calculating the OC and ASN. On the average, sequential sample plans have lower ASN's, and OC's are comparable to fixed sample-size procedures. The two most commonly used sequential procedures for insect sampling are Wald's probability ratio test and a test proposed by Iwao. Each of these methods has limitations. An alternative to sequential procedures is double sampling. Double sample plans developed for the Colorado potato beetle,Leptinotarsa decemlineata(Say), on Long Island, N.Y., have OC's comparable to a modified form of Iwao's sequential method and fixed sample size methods. They also have ASN's that at times are lower than those of the sequential method.

ISSN:0046-225X    

DOI:10.1093/ee/14.5.644

出版商:Oxford University Press    

年代:1985

数据来源: OUP

摘要:

Influence of light on larvae movement and distribution was investigated for the beet armyworm (BAW),Spodoptera exigua(Hübner), in the laboratory and the field. Laboratory tests with five light intensities ranging from 0–3,400 lx indicated that first instars were photopositive, second instars were weakly photonegative, neither third nor fourth instars responded behaviorally to light, and fifth instars demonstrated a strong photonegative reaction. Distribution within celery plants for fourth instars was unaffected by light in the laboratory. Fifth instar larvae responded to light in both the laboratory and the field: most larvae were found on leaves during dark phase, while during light phase a significant majority was observed in sheltered areas in celery hearts or on the ground. Implications for sampling BAW based on these results are discussed.

ISSN:0046-225X    

DOI:10.1093/ee/14.5.650

出版商:Oxford University Press    

年代:1985

数据来源: OUP