Pest Of Sugarcane Research Articles

Radiation Biology ofEldana saccharina(Lepidoptera: Pyralidae)

Laboratory-reared male and female Eldana saccharina Walker (Lepidoptera: Pyralidae: Gallerinae)—a major pest of sugarcane (Saccharum spp.; Poales: Poaceae) in South Africa—were exposed to increasing doses of γ-radiation to assess this species' suitability for the sterile insect technique as part of an area-wide integrated pest management (AW-IPM) program. Irradiated male and female moths were crossed with non-irradiated counterparts and irradiated counterparts at the same radiation dose. Male and female moths were treated with radiation doses of 150, 200, 250, 300 and 350 Gy, and the following crosses were made: irradiated males (T♂) mated with untreated females (U♀) and irradiated females (T♀) mated with untreated males (U♂). Males and females of the T♀ × T♂ cross were exposed to the same radiation doses except in the 350 Gy treatment. Fertility (egg hatch) declined significantly with increasing doses of radiation in all crosses. Female progeny from the T♀ × U♂ and T♀ × T♂ crosses were more sensitive to irradiation than female progeny from the U♀ × U♂ and U♀ × T♂ crosses and were completely sterile when treated with either 200 Gy or 150 Gy. Treated males mated with untreated females still had a residual fertility of 0.19% when exposed to 350 Gy of radiation. The fertility of E. saccharina is therefore sensitive to increasing doses of ionizing radiation and this species is a suitable candidate for further development of the SIT as a component of an AW-IPM program. The fecundity of untreated E. saccharina females mated with irradiated males was not affected by radiation. The availability of a great number of infertile eggs can be regarded as a benefit in a program where natural enemies are combined with the SIT because non-fertile eggs can provide additional hosts for egg parasitoids and be a food source for predators.

Mating Compatibility and Competitiveness between Wild and Laboratory Strains ofEldana saccharina(Lepidoptera: Pyralidae) after Radiation Treatment

Abstract The efficacy of the sterile insect technique (SIT) applied as part of area-wide integrated pest management (AW-IPM) depends on efficient transfer of sperm carrying dominant lethal mutations from sterile males to wild females. Success or failure of this strategy is therefore critically dependent on quality and ability of sterile males to search for and copulate with wild females. The African sugarcane borer, Eldana saccharina Walker (Lepidoptera: Pyralidae) is an economic pest of sugarcane targeted for control in South Africa using an AW-IPM approach with a SIT component. As part of further steps towards development of the technique, levels of mating competitiveness and compatibility were assessed by observing the extent to which individuals from different populations interbreed when confined together under both laboratory and semi-field conditions. Three types of pair-wise competition experiments were conducted: non-irradiated laboratory adults vs. non-irradiated wild adults, irradiated (200 Gy) ...

Resistance mechanisms of sugarcane cultivars to spittlebug Mahanarva fimbriolata

The spittlebug Mahanarva fimbriolata (Stal) (Hemiptera: Cercopidae) is one of the most important pests of sugarcane in Brazil. Measures for population control are currently restricted to the use of chemical insecticides and fungus Metarhizium anisopliae, in part because very little information exists regarding resistance of sugarcane cultivars. Therefore, the aim of this study was to evaluate resistance mechanisms of 12 different sugarcane cultivars to M. fimbriolata to provide information for growers for pest management. Isolated buds of each cultivar were planted in pots and kept in a greenhouse for approximately three months. The pots were then moved to climate test chambers (26 ± 1 oC; 70 ± 10 % relative humidity; 12 h photoperiod) to carry out laboratory tests to evaluate adult feeding and female oviposition preferences (using both free-choice and no-choice tests) as well as the effects of cultivars on nymph development and cultivars tolerance to pest attack. The least attractive cultivars for adult feeding were IACSP96-2042 and IAC91-1099. Cultivars IACSP96-2042, IACSP96-3060 and IACSP94-2101 received the fewest eggs in the free-choice and no-choice oviposition tests and exhibited some level of antixenosis resistance. Cultivar IAC91-1099 showed the highest level of antibiosis resistance with a nymph survival rate in the roots of only 20 %. Finally, cultivar IACSP94-2094 appears to be tolerant to M. fimbriolata, as it did not show significant reductions in aboveground biomass weight, despite showing reduced leaf chlorophyll levels following pest attack.

Impact of nitrogen fertilization on Mexican rice borer (Lepidoptera: Crambidae) injury and yield in bioenergy sorghum

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is a serious pest of sugarcane (Saccharum spp.), sorghum (Sorghum bicolor (L.) Moench), corn (Zea mays L.), rice (Oryza sativa L.), and related graminaceous bioenergy crops. A two-year field study was conducted in Jefferson County, TX to examine the impact of nitrogen (N) fertilization on E. loftini infestations and subsequent yields in cultivars of high-biomass and sweet sorghum. In 2013, percentage of bored internodes and number of adult emergence holes per stalk increased with higher N rates; however, only the percentage of bored internodes was impacted by N in 2014. Yields from both years indicated that N rate was positively associated with increases in stalk weight and ethanol productivity, but not sucrose concentration. Because higher N rates were associated with increased yields despite having greater levels of E. loftini injury, our data suggest that increases in yield from additional N outweigh decreases from additional E. loftini injury. Fertilization rates maintained between the recommended 45 and 90 kg N/ha minimize risks of negative area-wide impacts from increased production of E. loftini adults, while still allowing for optimum yields.

Impacts of Crop Residue on Damage by Sugarcane Pests During the Tillering Phase in Argentina

One of the most important recent changes in sugarcane cultural practices in Tucuman, Argentina, is the adoption of the practice of green-cane harvesting, which involves harvesting the sugarcane crop in the absence of burning. The objective of this study was to assess the impact of the postharvest crop residue (also sometimes known as “trash blanket”) on Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) and Pseudaletia uni puncta Haworth (Lepidoptera: Noctuidae) population dynamics in sugarcane. The study was conducted in ratoon crops for 3 growing seasons (2011, 2012, and 2013) and at 3 locations in the state of Tucuman, Argentina. The treatments consisted of rows with the crop residue burned and the crop residue retained. Removal of the crop residue by burning, compared with retention, resulted in significantly greater crop damage by E. lignosellus in all locations and years. In contrast, damage by P. unipuncta was observed exclusively on plots where crop residue was retained. Comparing the pest status of 2 insects, E. lignosellus seems to be more consistently deleterious to sugarcane yield than P. unipuncta, and chemical control of this species is not very effective. Therefore, leaving the crop residue in place seems to be the most appropriate crop management approach, although it is important also to monitor P. unipuncta populations in order to implement control should it be necessary.

Population Dynamics of Mexican Rice Borer,Eoreuma loftini(Dyar)1, Using a Pheromone Trap System in Sugarcane,Saccharum officinarumL., in Morelos, México

Abstract. The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is one of the most important pests of sugarcane, Saccharum officinarum L., in Mexico, but the population dynamics of the adult are not known for conditions in the state of Morelos. During the 2013 season, 11,282 adult males were caught, with the largest number of adults trapped on the eastern and western sides of the state. Two population peaks were observed, the first during the dry season (February-June) and the second during the rainy season (October- December). Implementing monitoring of this stalk borer as part of an integrated pest management program is discussed.

Effects of entomopathogenic fungi on different developmental stages of Cotesia flavipes (Cam.) a parasitoid of Diatraea flavipennella (Box) (Lepidoptera: Crambidae)

Biological control using the parasitoid Cotesia flavipes (Cam.) is one of the main components in the integrated management of the sugarcane moth borer Diatraea spp. Besides this parasitoid, the entomopathogenic fungi Beauveria bassiana (Bals.) Vuill and Metarhizium anisopliae (Metsch.) Sorok. are used to control sugarcane pests, and they can be found naturally parasitizing caterpillars. This study aimed to evaluate the effects of M. anisopliae and B. bassiana on different developmental stages of the C. flavipes parasitoid on Diatraea flavipennella (Box). The experiments were carried at laboratory with isolates PL 43 of M. anisopliae and ESALQ 447 of B. bassiana were applied to the parasitoid at the immature and adult phases. No negative effects were observed on the larval development of C. flavipes, and it could complete its development on caterpillars of D. flavipennella treated with fungi. The fungi did not cause pupal mortality. However, B. bassiana caused high mortality in the adult parasitoid (76%). The fungi had negative effects on parasitoids when applied during certain developmental stages of C. flavipes.

Efficacy of indigenous Steinernema abbasi and Heterorhabditis indica isolates as potential biocontrol agent against Holotrichia consanguinea Blanch. (Coleoptera: Scarabaeidae)

Holotrichia consanguinea is a serious pest of peanut and sugarcane that attacks other commercial crops in India. The efficacy of two species of entomopathogenic nematodes (EPN), Steinernema abbasi and Heterorhabditis indica, against H. consanguinea was tested under laboratory and field conditions. In a laboratory assay, H. indica caused significantly greater mortality (25-100%) than S. abbasi (20-80%) against second instars and H. indica caused 17.5-82.5% mortality in third-instar grub larvae, while S. abbasi caused (10-60%) mortality. These results revealed that second-instar grubs were more susceptible than third-instar grubs and efficacy of EPN against H. consanguinea varies with nematode species. The penetration and multiplication rate for H. indica was significantly higher than those of S. abbasi. Infective juveniles (IJ) of both nematode species and a commonly used insecticide (phorate) were tested against this insect in a field experiment. Field trail data showed that the percentage reduction in H. consanguinea grub population was significantly higher using H. indica at a dose of 2.5 × 109 IJ ha−1 than S. abbasi and phorate application. Phorate application was more efficient in reducing the grub population than both nematode species at the lower application rate (1.25 × 109 IJ ha−1). Overall, these experiments suggest that H. indica may be a promising biocontrol agent against H. consanguinea.

A 100 years of biological control of sugarcane pests in India: review and perspective.

Abstract Insect pests constitute a major biotic stress in sugarcane in India as they attack the crop from the time of planting until almost harvest, inflicting yield and sugar losses. Biological control has always received a prominent position among the pest management tools, facilitated by the unique semi-perennial crop habitat and low pesticide usage. Biocontrol research of the early 1930s and 40s was characterized by surveys focusing on identification and studies on the basic biology of natural enemies. Conservation and re-distribution, and introduction and colonization of predominant parasitoids was practiced very early, and even in the recent past, with remarkable success. Mass multiplication and field evaluation that began in the early decades continue today, as is demonstrated by the use of the most exploited parasitoid Trichogramma chilonis . Several parasitoids and predators of borers and sucking pests were investigated systematically when the need arose. Among entomopathogens, granulosis viruses and fungi received considerable attention; a simple formulation of Beauveria brongniartii reached commercial production for the control of the white grub Holotrichia serrata . In recent years, isolates of Bacillus thuringiensis from sugarcane soil have been examined and a scarabaeid-specific cry gene has been identified. Preliminary studies of kairomonal principles from borers as attractants to the larval parasitoid Cotesia flavipes have been carried out. Organizational support to the cause of biological control includes coordinated research efforts from government agencies, production of biocontrol agents by commercial insectaries and promotion of technologies by the sugar industry. In this review, we chronicle the major research findings over the past eight decades, portray an overview of their significance and project the prospects and priorities for biological control research and promotion in the country.

Specific Diversity of Metarhizium Isolates Infecting Aeneolamia spp. (Hemiptera: Cercopidae) in Sugarcane Plantations.

Spittlebugs from the genus Aeneolamia are important pests of sugarcane. Although the use of the entomopathogenic fungus Metarhizum anisopliae s.l. for control of this pest is becoming more common in Mexico, fundamental information regarding M. anisopliae in sugarcane plantations is practically non-existent. Using phylogenetic analysis, we determined the specific diversity of Metarhizium spp. infecting adult spittlebugs in sugarcane plantations from four Mexican states. We obtained 29 isolates of M. anisopliae s.str. Haplotype network analysis revealed the existence of eight haplotypes. Eight selected isolates, representing the four Mexican states, were grown at different temperatures in vitro; isolates from Oaxaca achieved the greatest growth followed by isolates from Veracruz, San Luis Potosi and Tabasco. No relationship was found between in vitro growth and haplotype diversity. Our results represent a significant contribution to the better understanding of the ecology of Metarhizum spp. in the sugarcane agroecosystem.

Prionic Acid: An Effective Sex Attractant for an Important Pest of Sugarcane, Dorysthenes granulosus (Coleoptera: Cerambycidae: Prioninae).

Male Dorysthenes granulosus (Thomson, 1860) (Coleoptera: Cerambycidae: Prioninae) were caught in traps baited with racemic 3,5-dimethyldodecanoic acid (prionic acid) during field screening trials in China that tested known cerambycid pheromones. This species is an important pest of sugarcane (Saccharum officinarum L.). In follow-up dose-response trials, plastic sachets loaded with 1 or 0.1 mg of prionic acid were equally attractive to male beetles, whereas lower doses were no better than controls. Two commercial prionic acid lures also were attractive, suggesting that traps baited with prionic acid can be rapidly incorporated into integrated pest management programs targeting this major pest. It is likely that this compound is a major component of the female-produced sex pheromone of D. granulosus because this species is in the same subfamily as Prionus californicus Motschulsky, 1845, the species from which prionic acid was originally identified.

Trichogramma parasitoids for control of Lepidopteran borers in Taiwan: species, life‐history traits and Wolbachia infections

AbstractTrichogramma, polyphagous endoparasitoids of lepidopteran eggs, are used against a variety of crop pests throughout the world including those of sugar cane and corn in south‐eastern Asia. Their ability to be easily and economically reared on factitious hosts and their wide host range have contributed to their widespread use in pest control. The overall aim of this study was to select strains for eventual release in crop areas for control of lepidopteran borer pests of sugar cane and corn. To this end, we identified common Trichogramma species emerging from corn borer egg masses throughout south‐western Taiwan, compared their life‐history characteristics, assessed their thermal limits and identified the Wolbachia infection status of collected Trichogramma parasitoids. Trichogramma ostriniae was the most commonly collected species on corn, with occasional detection of T. chilonis and an unidentified species designated as T. sp. y. Although the sex ratio varied widely between sites, Wolbachia infection was detected only at a single site in one species (T. ostriniae). Wolbachia‐infected T. ostriniae were tolerant to high temperature stress. Trichogramma chilonis had lowest fecundity of the three species tested, and a Wolbachia‐infected T. ostriniae strain had lower fecundity than an uninfected strain. Given the limited availability of distribution and historical data for Trichogramma species in Taiwan, the current study provides a baseline for future work and also highlights the importance of accurately identifying species when establishing colonies of natural enemies for biocontrol.

Testis Morphology and Dichotomic Spermatogenesis in the Sugarcane Borer Diatraea saccharalis (F.) (Lepidoptera: Crambidae).

In the present study, we describe the testis morphology and spermatogenesis of the sugarcane borer, one of the most destructive pests of sugarcane, using light, transmission, and scanning electron microscopies. Diatraea saccharalis (F.) larvae have paired, kidney-shaped testes that are limited externally and divided into four follicles by tunica cells. The adults have two fused whitish and spherical testes that are divided into eight follicles and are composed of spermatogonia, spermatocyte, spermatid, and sperm bundles. The spermatogonia and spermatocyte cysts are located at the apical extremity of the follicle, while the spermatid cysts and sperm bundles are located at the basal extremity of the follicle. Inside of the cysts, which are formed by the somatic cells, the germ line cells develop synchronously and are interconnected by cytoplasmic bridges. Each cyst contains only apyrene or eupyrene, and none of the cysts contain both of the cells. The inner part of the apyrene cyst consists of an electron-dense cap as opposed to a nucleus. The eupyrene sperm contains a nucleus, acrosome, and reticular and lacinate appendages. Both of the sperm types have a "9 + 9 + 2" axoneme and two mitochondrial derivatives at the tail region. The spermatogenesis process and spermatozoa morphology are similar to that of other Lepidoptera.

Response of Sugarcane and Sugarcane Stalk Borers Sesamia spp. (Lepidoptera: Noctuidae) to Calcium Silicate Fertilization.

Sugarcane is grown extensively throughout the world including more than 100,000ha in Khuzestan province, Iran. The pink stalk borers Sesamia are key pests of sugarcane in this region, while other stalk borers will occur in sugarcane worldwide. Application of silicon as a soil amendment has provided plant mitigation to both biotic and abiotic stresses. Silicon has been shown to enhance resistance of sugarcane against stalk borers. Field trials were conducted to determine the effects of calcium silicate against infestations of stalk borers Sesamia spp. and on yield quality. Experiments were conducted with three sugarcane varieties CP69-1062, IRC99-01, and SP70-1143 and two rates of calcium silicate (400 and 800kg/ha). Percentage of stalk damaged, percentage of bored internodes, length of borer tunnel (mm), number of larvae + pupae per 100 stalks, number of exit holes, and cane yield quality were determined. We demonstrate significant reduction on borer population and damage under silicon treatment, but greater reduction in the percentages of stalk damage, bored internodes, moth exit holes, and length of borer tunnel and number of larvae and pupae per 100 stalks were observed in the susceptible variety CP69-1062. Silicon treatment positively affected cane and sugarcane juice quality of for the variety CP69-1062, but not for SP70-1143. We conclude that the benefits of silicon to sugarcane quality and sugarcane resistance to stalk borers are dependent on the sugarcane variety.

A Relative Resistance Ratio for Evaluation of Mexican Rice Borer (Lepidoptera: Crambidae) Susceptibility Among Sugarcane Cultivars.

The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane (hybrids of Saccharum spp.) in Louisiana and Texas. Resistance to E. loftini was evaluated in 51 commercial and experimental cultivars of sugarcane, energycane (hybrids of Saccharum spp.), and sorghum [Sorghum bicolor (L.) Moench and hybrids of Sorghum spp.] in four replicated small plot field experiments from 2009 to 2012. A relative resistance ratio was developed to compare levels of susceptibility among cultivars based on the percentage of bored internodes and survival to adulthood. This index was able to separate cultivars into five resistance categories and provides a new method for comparing levels of resistance among cultivars. E. loftini pest pressure in 2009 was among the highest recorded with injury ranging from 55 to 88% bored internodes. Commercial sugarcane cultivar HoCP 85-845 was identified as resistant in three of four experiments, whereas HoCP 04-838 was identified as susceptible in all experiments. Of the five sugarcane cultivars in commercial production in the Rio Grande Valley of Texas, only TCP 87-3388 was categorized as resistant. Of the cultivars with potential for bioenergy production, all of the energycane cultivars demonstrated higher levels of resistance than high-biomass and sweet sorghum cultivars. Continued evaluation of cultivar resistance to E. loftini is important to development of effective integrated pest management strategies for this pest.

Expansion of the Mexican Rice Borer (Lepidoptera: Crambidae) into Rice and Sugarcane in Louisiana.

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is an invasive pest of sugarcane, Saccharum spp., rice, Oryza sativa L., and other graminaceous crops in the Gulf Coast region of the United States. Traps baited with E. loftini female sex pheromones were used to document establishment and distribution of E. loftini near sugarcane, rice, and noncrop hosts in seven southwest Louisiana parishes from 2009 to 2013. Additional field surveys documented larval infestations in commercial sugarcane and rice. After its initial detection in 2008, no E. loftini were detected in Louisiana in 2009 and only two adults were captured in 2010. Trapping documented range expansion into Cameron, Beauregard, and Jefferson Davis parishes in 2011 and Allen, Acadia, and Vermilion parishes in 2013. During the course of this study, E. loftini expanded its range eastward into Louisiana 120 km from the Texas border (≈22 km/yr). Surveys of larval infestations provided the first record of E. loftini attacking rice and sugarcane in Louisiana. Infestations of E. loftini in rice planted without insecticidal seed treatments in Calcasieu Parish reached damaging levels.

Suppression of green chafer Anomala albopilosa (Coleoptera: Scarabaeidae) populations by mass trapping with light traps

To control one of the most destructive sugarcane pests, Anomala albopilosa (Hope) (Coleoptera: Scarabaeidae), mass trapping with light traps was conducted in the farmlands of the Miyako Islands from mid-April and early May to late July from 2008 to 2013. As a result of trapping, trap catches significantly decreased by 52, 89, and 28 % on the islands of Miyako, Irabu-Shimoji, and Tarama, respectively. The mean larval density in the sugarcane fields decreased by 91, 90, and 73 % on Miyako, Irabu-Shimoji, and Tarama, respectively, during this period; the difference was statistically significant for the first two cases. These results indicated that mass trapping with light traps effectively reduced these isolated populations of A. albopilosa. The effect of the light traps on A. albopilosa behavior is also discussed.

Genetic Diversity and Structure of Brazilian Populations of Diatraea saccharalis (Lepidoptera: Crambidae): Implications for Pest Management.

The sugarcane borer, Diatraea saccharalis (F.), is the main pest of sugarcane in Brazil. Genetic variability and gene flow among 13 Brazilian populations of the species were evaluated based on mitochondrial DNA sequences to estimate the exchange of genetic information within and among populations. We found high genetic structure among sampled localities (ΦST=0.50923), and pairwise genetic distances were significantly correlated to geographic distances. Demographic analysis and genealogical network of mitochondrial sequences indicate population growth and admixture of D. saccharalis populations, events likely related to the sequential expansion of the corn and sugarcane crops in Brazil. The implications of these findings for pest management are discussed.

Low genetic diversity in Melanaphis sacchari aphid populations at the worldwide scale.

Numerous studies have examined the genetic diversity and genetic structure of invading species, with contrasting results concerning the relative roles of genetic diversity and phenotypic plasticity in the success of introduced populations. Increasing evidence shows that asexual lineages of aphids are able to occupy a wide geographical and ecological range of habitats despite low genetic diversity. The anholocyclic aphid Melanaphis sacchari is a pest of sugarcane and sorghum which originated in the old world, was introduced into the Americas, and is now distributed worldwide. Our purpose was to assess the genetic diversity and structuring of populations of this species according to host and locality. We used 10 microsatellite markers to genotype 1333 individuals (57 samples, 42 localities, 15 countries) collected mainly on sugarcane or sorghum. Five multilocus lineages (MLL) were defined, grouping multilocus genotypes (MLG) differing by only a few mutations or scoring errors. Analysis of a 658 bp sequence of mitochondrial COI gene on 96 individuals revealed five haplotypes, with a mean divergence of only 0.19 %. The distribution of MLL appeared to be strongly influenced by geography but not by host plant. Each of the five MLL grouped individuals from (A) Africa, (B) Australia, (C) South America, the Caribbean and the Indian Ocean including East Africa, (D) USA, and (E) China. The MLL A and C, with a wide geographic distribution, matched the definition of superclone. Among aphids, M. sacchari has one of the lowest known rates of genetic diversity for such a wide geographical distribution.

Evidence of environmental and vertical transmission of Burkholderia symbionts in the oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae).

The vertical transmission of symbiotic microorganisms is omnipresent in insects, while the evolutionary process remains totally unclear. The oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae), is a serious sugarcane pest, in which symbiotic bacteria densely populate the lumen of the numerous tubule-like midgut crypts that the chinch bug develops. Cloning and sequence analyses of the 16S rRNA genes revealed that the crypts were dominated by a specific group of bacteria belonging to the genus Burkholderia of the Betaproteobacteria. The Burkholderia sequences were distributed into three distinct clades: the Burkholderia cepacia complex (BCC), the plant-associated beneficial and environmental (PBE) group, and the stinkbug-associated beneficial and environmental group (SBE). Diagnostic PCR revealed that only one of the three groups of Burkholderia was present in ∼89% of the chinch bug field populations tested, while infections with multiple Burkholderia groups within one insect were observed in only ∼10%. Deep sequencing of the 16S rRNA gene confirmed that the Burkholderia bacteria specifically colonized the crypts and were dominated by one of three Burkholderia groups. The lack of phylogenetic congruence between the symbiont and the host population strongly suggested host-symbiont promiscuity, which is probably caused by environmental acquisition of the symbionts by some hosts. Meanwhile, inspections of eggs and hatchlings by diagnostic PCR and egg surface sterilization demonstrated that almost 30% of the hatchlings vertically acquire symbiotic Burkholderia via symbiont-contaminated egg surfaces. The mixed strategy of symbiont transmission found in the oriental chinch bug might be an intermediate stage in evolution from environmental acquisition to strict vertical transmission in insects.