Predictive Modeling of Spinner Dolphin (Stenella longirostris) Resting Habitat in the Main Hawaiian Islands

Predictive habitat models can provide critical information that is necessary in many conservation applications. Using Maximum Entropy modeling, we characterized habitat relationships and generated spatial predictions of spinner dolphin (Stenella longirostris) resting habitat in the main Hawaiian Islands. Spinner dolphins in Hawai'i exhibit predictable daily movements, using inshore bays as resting habitat during daylight hours and foraging in offshore waters at night. There are growing concerns regarding the effects of human activities on spinner dolphins resting in coastal areas. However, the environmental factors that define suitable resting habitat remain unclear and must be assessed and quantified in order to properly address interactions between humans and spinner dolphins. We used a series of dolphin sightings from recent surveys in the main Hawaiian Islands and a suite of environmental variables hypothesized as being important to resting habitat to model spinner dolphin resting habitat. The model performed well in predicting resting habitat and indicated that proximity to deep water foraging areas, depth, the proportion of bays with shallow depths, and rugosity were important predictors of spinner dolphin habitat. Predicted locations of suitable spinner dolphin resting habitat provided in this study indicate areas where future survey efforts should be focused and highlight potential areas of conflict with human activities. This study provides an example of a presence-only habitat model used to inform the management of a species for which patterns of habitat availability are poorly understood.     

Genus Paracymoriza Warren from China (Lepidoptera: Crambidae: Nymphulinae)

This paper deals with 13 species of the genus Paracymoriza Warren from China. Paracymoriza multispinea You, Wang et Li sp. n. is described as new to science; Paracymoriza fuscalis (Yoshiyasu) is recorded for the first time from this country. A key to the Chinese species is provided.     

Complete mitochondrial genome of Chilo suppressalis (Walker) (Lepidoptera: Crambidae)

The complete sequence of the mitochondrial genome (mitogenome) of the rice stem borer Chilo suppressalis (Walker) (Lepidoptera: Crambidae) was determined to be 15,465 bp. It contains 13 protein-coding genes (PCGs), 22 tRNA genes, the large and small rRNA genes, and an A+T-rich region. The nucleotide composition of the mitogenome of C. suppressalis is highly A+T biased, accounting for 79.70% in whole mitogenome, 77.74% in PCGs, 84.70% in tRNAs, 81.20% in rRNAs and 94.19% in A+T-rich region, respectively. The PCGs have typical ATN start codons, except for cox1, which contains the unusual CGA. The C. suppressalis A+T-rich region contains a conserved structure combining the motif ATAGA and a 19-bp poly-T stretch, but absence of the 9-bp poly-A element upstream trnM.     

Epicuticular hydrocarbons of the sugarcane borer Diatraea saccharalis (Lepidoptera: Crambidae)

The epicuticular hydrocarbons of the larval, pupal and adult stages of the sugarcane borer Diatraea saccharalis Fabricius (Lepidoptera: Crambidae) are analysed. Dramatic changes are observed between the stages studied. Adult hydrocarbons are mostly saturated, with a predominance of 1–4 methyl‐branched straight carbon skeletons of 37–47 atoms; the major components are isomeric mixtures of internally branched trimethylderivatives of C39, C37 and C41 carbon backbones. By contrast, very small amounts of methyl‐branched components are detected in the pupae, although straight chain hydrocarbons of 23–35 carbons are the prevailing structures (70.7 ± 3.4%) with n‐C29 and n‐C27 as the major components. Unsaturated hydrocarbons (29.0 ± 3.5%) of similar chain lengths elute by gas chromatography of epicuticular extracts as complex mixtures of mono‐, di‐ and trienes; with the degree of unsaturation increasing with chain length. This is the first report of very long chain unsaturated hydrocarbons in cuticular extracts of a larval lepidopteran (93.3 ± 0.6% of the lipid components), with chain lengths in the range 37–53 carbons and up to four double bonds; the major component being C49:3, which co‐elutes with C49:4 and C49:2.     

Conventional resistance of experimental maize lines to corn earworm (Lepidoptera: Noctuidae), fall armyworm (Lepidoptera: Noctuidae), southwestern corn borer (Lepidoptera: Crambidae), and sugarcane borer (Lepidoptera: Crambidae)

Plant resistance is a useful component of integrated pest management for several insects that are economically damaging to maize, Zea mays L. In this study, 15 experimental lines of maize derived from a backcross breeding program were evaluated for resistance to corn earworm, Helicoverpa zea (Boddie); fall armyworm, Spodoptera frugiperda (J. E. Smith); southwestern corn borer, Diatraea grandiosella Dyar; and sugarcane borer, Diatraea saccharalis (F.). Experimental line 100-R-3 was resistant in the field to leaf feeding by fall armyworm and line 116-B-10 was resistant in the field to leaf feeding by fall armyworm and leaf and stalk feeding by southwestern corn borer. When corn earworm larvae were fed field harvested silks from experimental line 81-9-B in the laboratory, their pupal weights were significantly lower than the pupal weights of larvae that were fed silks from the resistant control, Zapalote Chico. Maysin levels lower than those commonly associated with corn earworm resistance were present in the resistant experimental line, 107-8-7, indicating a new basis confers resistance to corn earworm in this line. These resistant experimental lines will provide plant breeders with new sources of resistance to lepidopterous insects for the development of improved maize breeding populations.     

Susceptibility of Diatraea saccharalis (Lepidoptera: Crambidae) to tebufenozide.

Dosage-mortality baselines were determined for first and newly molted third instars of the sugarcane borer, Diatraea saccharalis (F.), with tebufenozide incorporated into an artificial diet. Using death as an endpoint for these assays, LC50 and LC90 values were estimated to be 0.17 and 0.41 ppm for the first and 0.87 and 3.67 ppm for third instars, respectively. Developmental effects also were observed and were defined to include mortality as well as physical impairment and retarded or prolonged development with absence of feeding. Concentrations causing developmental effects in treated larvae (EC50 and EC90) were 5.8- and 3.8-fold lower than the LC50 and LC90, respectively. The critical time of exposure to tebufenozide was determined for developmentally synchronous third instars to be less than 12 h postecdysis. Mortality through adult emergence significantly decreased from 92% (treatment at 0 h postecdysis) to 30% (treatment at 12 h postecdysis), when exposed to tebufenozide at the EC50. For surviving larvae, length of development time until pupation was significantly increased and female pupal weight significantly decreased when larvae were treated at 0 h postecdysis into the third instar. In addition, to modifying the traditional ways of assessing mortality 0-3 d postapplication, this study points out the value of using other approaches to pesticide assessment, especially where insect growth regulators are involved.     

中国水螟亚科二新种记述(鳞翅目:草螟科)

记述了采自天津及河北、福建等地的水螟亚科Nymphulinae 2新种, 即 环波水螟Paracymoriza convallata, sp. nov.和白筒水螟Parapoynx candida, sp. nov..模式标本保存于南开大学生物系, 天津.1. 环波水螟Paracymoriza convallata,新种(图1,3)前翅长♂9.0 mm.正模♂, 福建永泰县青云山 (25.52°N,118.57°E),550 m,2002-Ⅸ-18,王新谱采.新种与华南波水螟Paracymoriza laminalis (Hampson) 相似,主要区别在新种前翅中线外白区前缘封闭;雄性外生殖器抱器瓣基部较窄,端部较圆.2. 白筒水螟Parapoynx candida,新种(图2,4～5)前翅长♂11.5～12.0 mm;♀11.5 mm.正模♂,天津武清县 (39.31°N,116.51°E),1976-Ⅵ-22, 王印来采.副模1♂,天津市板桥农场(38.52°N,117.28°E),1976-Ⅵ(采集人不明);1♀,河北大城县 (38.40°N,116.39°E),1976-Ⅵ-12 (采集人不明).此新种与重筒水螟Parapoynx stratiotata (Linnaeus) 相近,区别在于新种外横线至翅外缘白色;雌性外生殖器无明显囊突.     

Monitoring of the European corn borer (Lepidoptera: Crambidae) in central Maine

Pheromone trap types and within-field trap locations were compared for their effectiveness in monitoring the flight activity of European corn borer, Ostrinia nubilalis (Hübner), and its relationship to egg mass density and crop damage in sweet corn in central Maine from 1995 to 1996. The use of both 3:97 Z:E-11-tetradecenyl acetate and 97:3 Z:E-11 tetradecenyl acetate pheromone blends confirmed that European corn borer in central Maine is attracted to both pheromone lure types. European corn borer moths were captured predominantly with the E-lure type than with the Z-lure type in both years. The Scentry Heliothis trap was more effective than the Multi-Pher trap, but similar to the pheromone-baited water pan trap for monitoring European corn borer flights. With the Scentry Heliothis trap, the grassy border and 1st corn rows were the best locations for moth capture during the early flight period, but during the peak flight period, traps located in the middle of the field caught the most moths. Corn damage was recorded before moth captures in some sites and before egg mass counts in others, indicating poor efficacy of traps for early flights. Significant and positive correlations were found between moth captures in the midfield location and egg mass counts, and corn leaf damage, and between egg mass counts and corn leaf damage. However, low coefficients of variation suggest that pheromone trap captures were not good predictors of European corn borer leaf damage in sweet corn.     

Taxonomic review of the subfamily Schoenobiinae(Lepidoptera:Pyraloidea:Crambidae) from China

The taxonomy of the Chinese Schoenobiinae is revised.In total,12 genera and 49species are recognized.This paper presents keys to the genera and species,illustrations of wing venation for each genus,and line drawings of genitalia of most species.Two new species,namely,Schoenobius scirpus sp.nov.and Ramila minima sp.nov.,are described.The female of Scirpophaga adunctella Chen,Song,and Wu,2006 is reported for the first time.Donacaula forficellus(Thunberg,1794) reported by Wang(1980) is proven to be a misidentification of S.scirpus sp.nov.The diagnostic characteristics of Schoenobiinae and the taxonomic status of some genera are discussed.Acropentias,Leechia,Brihaspa,and Promacrochilo are suggested to be removed from the subfamily because these genera do not share any synapomorphic characters with Schoenobiinae.     

Temperature-dependent development of diapausing larvae of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae)

Temperature-dependent development rate, percent diapause induction (hibernation at low temperature and aestivation at high temperature), and survival of diapausing larvae of Chilo partellus (Swinhoe, 1885) were examined on 13 constant temperatures ranging from 8 to 40 °C. Development of hibernating and aestivating larvae occurred from 10 to 25 °C and 27–38 °C, respectively. However, no development occurred at 8 °C and 40 °C. To determine actual thermal conditions that affect development and trigger both kind of diapause (hibernation and aestivation), various thermal parameters were estimated by fitting the development rate data to two linear (Ordinary equation and Ikemoto & Takai) models and thirteen non-linear models. The lower thermal thresholds (T_min) for development of diapausing larvae of C. partellus were calculated as 9.60 °C and 10.29 °C using the ordinary linear model and Ikemoto & Takai model, respectively. Similarly, the thermal constants (K) estimated using the ordinary linear model was 333.33 degree-days and that estimated with Ikemoto & Takai model was 338.92 degree-days. Among the non-linear models, Lactin-2 followed by Lactin-1 were found to be the best as these models estimated the critical temperatures (T_min, T_max and T_opt) similar to those of observed values. Conclusively, the Ikemoto & Takai linear model and Lactin-2 followed by Lactin-1 non-linear models are useful and efficient for describing temperature-dependent development and estimating the temperature thresholds of diapausing larvae of C. partellus. Our findings provided fundamental information for estimation of thermal requirement and temperature based development models for diapausing larvae of C. partellus. This information will be highly useful for predicting the occurrence, seasonal emergence, number of generations and population dynamics of C. partellus.     

Feminizing Wolbachia in an insect,Ostrinia furnacalis (Lepidoptera: Crambidae)

Wolbachia, which forms a group of maternally inherited bacteria in arthropods, often cause reproduction alterations in their hosts, such as cytoplasmic incompatibility, parthenogenesis, male-killing, hybrid breakdown and feminization. To date, Wolbachia-induced feminization has been reported only in isopods. Here we report that a Wolbachia strain feminizes an insect host, Ostrinia furnacalis. Among 79 wild females of O. furnacalis examined, Wolbachia infection was detected in 13 females. Twelve of the 13 infected females produced all-female progenies, and this trait was maternally inherited. Tetracycline treatment of thelygenic matrilines resulted in the production of all-male progenies. The present findings indicate that the Wolbachia infection induces feminization of genetic males in O. furnacalis. Differences in the Wolbachia-induced feminization in O. furnacalis and that in isopods are discussed along with the differences in sex determination mechanisms between insects and isopods. Phylogenetic analysis of the wsp gene sequence of Wolbachia suggests independent evolutionary origins for the Wolbachia-induced feminizations in O. furnacalis and in isopods. Our findings over 5 years suggest that the infection has been maintained at a low prevalence in the O. furnacalis population.     

Proteolytic profile in the larval midgut of Chilo suppressalis Walker (Lepidoptera: Crambidae)

Chilo suppressalis is a key constraint on production of rice. The current research was conducted to study the types of digestive proteases in the larval midgut of C. suppressalis. It was found that activity of total digestive proteases increased from the first to the fifth larval instars, which showed different nutritional requirements. Four types of proteinases and two types of exopeptidase were identified so that their activities from the highest to the lowest activities is trypsin‐like, chymotrypsin‐like and elastase for proteinases, and amino and carboxypeptidases for exopeptidases. Meanwhile, just one type of cysteine protease, cathepsin D, was determined in the fourth and fifth instar larvae. The optimal pH for activity of total protease was found to be pH 9–10 and optimal temperature was observed to be 35–40°C, where there was the highest proteolytic activity. Some specific inhibitors of proteases including PMSF, TLCK, TPCK, DTT, E‐64, cystatin, phenanthroline and EDTA were used to confirm the types of proteases in the midgut of C. suppressalis.     

Sugarcane borer (Lepidoptera: Crambidae) resistance to transgenic Bacillus thuringiensis maize

Transgenic maize, Zea mays L., expressing the Bacillus thuringiensis (Bt) CrylAb toxin has been planted to extensive areas across the United States and several other countries, but no resistance has been documented in field populations oflepidopteran target pests. This article describes the first report of resistance alleles to commercially available Cry1Ab Bt maize in a Louisiana population of sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Crambidae). Two hundred thirteen two-parent isolines of D. saccharalis were screened for Cry1Ab resistance on Bt maize leaf tissue using an F2 screening technique. Larvae representing three isolines survived >15 d on Bt tissue in the F2 generation. The second generation backcross progeny (B1F2) derived from isoline 52 completed larval development on Bt maize in the greenhouse. Segregation and resistance frequency analysis associated with isoline 52 suggested that Bt resistance is probably determined by a nearly completely recessive allele at a single locus. With this assumption, the estimated resistance allele frequency in this population is 0.0023, within a 95% confidence interval of 0.0003-0.0064.     

Movement of Mexican rice borer (Lepidoptera: Crambidae) through the Texas rice belt

Pheromone-baited traps were used to monitor the movement of the Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), through the Texas rice belt from 2000 to 2005. Based on location of discovery in each county and year, the average rate of spread from 1980 to 2005 was 23 km/yr. From 2000 to 2005, the leading edge of the infestation has moved 16.5 km/yr toward Louisiana. The 1.8-fold increase (99% confidence interval) of the area occupied from 2000 to 2005 in the Texas rice belt indicates an expansion of the distribution of E. loftini. If movement continues to occur at similar rates, E. loftini will reach Louisiana by 2008.     

Chemical analysis of the female sex pheromone in Palpita nigropunctalis (Lepidoptera: Crambidae)

The lilac pyralid, Palpita nigropunctalis Bremer (Lepidoptera: Crambidae), is a common pest of Oleaceae plants. A crude extract of the female sex pheromone glands was examined by gas chromatography-electroantennogram detection (GC-EAD) and GC coupled to a mass spectrometer (GC/MS). The GC-EAD analysis revealed three EAG-active components (I–III) in a ratio of 1:0.2:0.01 (I: II: III). GC/MS analysis successfully recorded the mass spectra of I and II. For I, ions at m/z 238 (M⁺) and 220 ([M-18]⁺) indicated the structure of a monoenyl aldehyde with a 16-carbon chain. For II, M⁺ was not detected, but ions at m/z 222 ([M-60]⁺) and 61 ([AcOH+1]⁺) suggested that II was a monoenyl acetate with a 16-carbon chain. Further GC/MS analysis of the extract treated with dimethyl disulfide revealed that the double bonds in both I and II are located at the same position of 11th-carbon. In addition, the pheromone extract was examined by GC/Fourier transform-infrared spectrophotometer (GC/FT-IR). An IR spectrum of I showed characteristic absorption at 1716 and 966?cm^?1, indicating a formyl group and E configuration of the double bond, respectively. In the case of II, absorption at 1745 and 968?cm^?1 indicated an ester carbonyl and E configuration, respectively. Taken together and by comparison with authentic standards, I and II were confirmed as (E)-11-hexadecenal and (E)-11-hexadecenyl acetate, respectively; while III was speculated as (E)-11-hexadecen-1-ol. The synthetic I, II and III all coincided well with those of the natural components in chemical data, and elicited strong electroantennographic activity in male P. nigropunctalis.     

Resistance to stem borers (Lepidoptera: Crambidae) among Texas rice cultivars

A 4-yr field study was conducted to assess the resistance of rice, Oryza sativa L., cultivars to injury from the sugarcane borer, Diatraea saccharalis (F.), and the Mexican rice borer, Eoreuma loftini (Dyar) (both Lepidoptera: Crambidae). Several cultivars showed reduced levels of injury ('CLXL8', 'XL8', 'Wells', 'Cheniere', and 'XP710' in 2003; CLXL8, XP723, Cheniere, and 'CL161' in 2004) and lower stem borer yield loss (CLXL8 in 2004) than the more susceptible 'Priscilla'. The resistant CLXL8 also had less injury and yield loss in 2004 and higher yield in 2003 than 'Cocodrie', currently the most popular rice cultivar in Texas and Louisiana. Linear regression analyses between whiteheads and main crop rice yield showed steeper negative slopes for the more resistant cultivars than the more susceptible cultivars, indicating a greater yield loss per whitehead on the resistant cultivars. Compensation from insect injury likely explains the positive associations established in our study between main crop yield and whiteheads for some cultivars. Cultivar resistance is anticipated to become a major control tactic in reducing infestations of E. loftini and D. saccharalis in the Texas and Louisiana rice industries.     

Resistance to Diaphania hyalinata (Lepidoptera: Crambidae) in Cucumis species.

Diaphania hyalinata (L.), the melonworm, causes economic damage in cucurbit species in the Caribbean region. To control larvae feeding on leaves, frequent pesticide applications are needed, but this favors outbreaks of other pests. We looked for plant resistance to D. hyalinata in Cucumis melo L. and two wild Cucumis, C. metuliferus Meyer and C. pustulatus Naudin. Fifteen genotypes were observed using a 1-81 damage scale during 8 wk in two field trials in Guadeloupe, French West Indies. Among the C. melo genotypes, we observed different levels of damage (scores of 32-74 at the maximum damage date) ranging from partially resistant to susceptible genotypes. Both wild species scored <20 at the maximum damage date, and were more resistant in the field tests than the tested genotypes of C. melo. Five C melo genotypes and one C. pustulatus genotype were tested using a detached leaf test. Under controlled conditions, newly hatched larvae were fed with leaves from plants that were 5-9 wk old. Duration and mortality of immature stages were highly correlated. Strong antibiosis (long development and high mortality) was expressed by PI 140471 and Concombre Chien (two C. melo genotypes). For both genotypes, mortality was at least 87.9 versus 34% for Védrantais, a susceptible genotype. Because antibiosis and field resistance were not correlated, we hypothesize that some genotypes expressed antixenosis in the field trials. In addition, possibilities of breeding for C. melo resistance to D. hyalinata is discussed.