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Maruca vitrata is an important pantropical and polyphagous insect pest of grain legumes. The adult emergence pattern and temporal variations in the calling and mating behaviour of M. vitrata across ages were studied. Observations revealed that adult emergence was not influenced significantly by sex, but by the time of the day. Calling activity is a strong determinant of male mating success in insects. An age-dependent female calling pattern was observed. Females seldom called on their day of emergence, calling percentage was low to nil in the first four hours of scotophase but reached a peak in the fifth hour. The calling patterns of females of different ages were similar except that there were two peaks of calling for 3 and 4 days old females. Like calling, the mating pattern was also age-dependent, i.e. M. vitrata mating frequency was maximum at 3-days of age and thereafter decreased gradually with age. The highest mating frequency (30.83%) was observed at 2200 h for 3-day-old moths. The current study revealed that age dependant and distinct patterns in female calling, synchronous male responsiveness leading to mating in M. vitrata. The output of the study could be utilized in various aspects of M. vitrata semiochemical based research.

The leaf-eating caterpillar,Opisina arenosellaWalker, is the most destructive pest of coconut palm in India and Southeast Asia. The management practices employed againstO. arenosellaso far have been unsuccessful in many instances in India, due to the pest behaviour and coconut palm phenology. The life cycle, incidence and behaviour ofO. arenosellaare rather interesting and useful for the intervention of pheromone trapping technique for its management. We conducted the present study with the intention of identifying the female sex pheromone ofO. arenosellaand testing its efficacy under field conditions. Gas chromatography coupled electroantennographic detection (GC–EAD) and gas chromatography–mass spectrometry (GC–MS) analysis of female pheromone glands extract of one-day-oldO. arenosellafemales confirmed the presence of (Z,Z,Z)-3,6,9-tricosatriene (Z3Z6Z9-23Hy) as the dominant sex pheromone component. The male antennal response to female pheromone gland extract and syntheticZ3Z6Z9-23Hy was recorded using GC–EAD, and the results revealed that antennal response was positive to both the treatments at 0.13 mV and 0.14 mV respectively, compared to control (air), which was 0.016 mV. It was also evident from wind-tunnel experiments that the male moth response was high (80%) with the female gland extract, compared to 60% with synthetic pheromone and 0% for control (air). Male moths caught in the traps with and without lure were assessed in two field sites and recorded 69.26% and 54.25% more moth catches in the traps with the lure. We also observed a similar result in the cage experiment in which male moths caught in the traps with and without lure were 64.50% and 12.40%, respectively. The study also confirmed that 93.20% moths caught in the pheromone-baited traps were male. From the study, it is evident that the presence of (Z,Z,Z)-3,6,9-tricosatriene, which is the sex pheromone compound from the female gland extract ofO. arenosella, is an effective attractant in pheromone traps for the male moth under field conditions.

To distinguish host or nonhost plant of a phytophagous insect, it is important that a standardized procedure is in place. Disc method used for chewing and biting insects is described in this chapter. The statistical methods that can be employed are also mentioned.

Among castor plant types, spineless spike type exhibited resistance to the borer, Conogethes. Among cardamom plant types, Malabar clones exhibited borer resistance. Host shift experiments and other laboratory studies revealed that Conogethes population feeding on cardamom are genetically different from those feeding on castor. The patterns and relationships between the borer and the above two plants are different and independent. The larval behavioural responses were different on the two plants. A combination of antixenosis and antibiosis together with tolerance mechanism conferred resistance to the plants against the borer, Conogethes, attack. Conogethes borer-resistant plants play a vital role in pest management as resistant plants offer an ideal means of borer suppression.

Fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) is a pest of maize native to America that invaded India recently in 2018. Field and laboratory experiments were conducted in Bengaluru, India to find a suitable pheromone blend for trapping males of fall armyworm. The field evaluation studies showed that pheromone blend with Z-9-tetradecenyl acetate, Z-11-hexadecenyl acetate and Z-7-dodecenyl acetate in 87: 12.5 : 0.5 ratio attracted and trapped statistically significant number of male moths compared to other five blends using funnel traps. The laboratory evaluation of 6 different pheromone blends using Electroantennogram (EAG) with male antenna of S. frugiperda elicited statistically on par responses with each other. From the different dosage field study with optimum attracting blend, it was found that 2 mg loading trapped highest number of moths and was statistically on par with 3 mg pheromone lure. Further monitoring study carried out under farmer's field condition with 2 mg loading of pheromone blend with Z-9-tetradecenyl acetate, Z-11-hexadecenyl acetate and Z-7-dodecenyl acetate in 87: 12.5: 0.5 ratio found to be more effective in attracting and trapping male moths up to 60 days.

Conogethes punctiferalis (Guenee) is a critical pest that commonly infests castor (Ricinus communis Linnaeus) and cardamom (Elettaria cardamomum Maton) in India. The moths of both castor and cardamom appear to be similar in wing pattern and color. However, the results of behavioral studies elicited a doubt that there may be differences in terms of host specialization. In the present study, we conducted morphological studies and DNA barcode analyses using cytochrome oxidase I gene, which unraveled the mystery of C. punctiferalis breeding on castor and cardamom. The differences in male aedeagus and female bursae were prominent, yet, not sufficient enough to say that they are different species. The results showed high haplotype diversity (0.817 ± 0.073) and nucleotide diversity (0.0285 ± 0.002) in C. punctiferalis. In addition, topologies of neighbor-joining trees indicate that Conogethes sp. breeding on castor belongs to C. punctiferalis while those on cardamom are of a separate clade. Further genetic analysis revealed significant genetic differentiations among the two sampled populations, reflecting limited gene flow. Neutrality tests and mismatch distributions showed population expansion in C. punctiferalis, while the results of an analysis of molecular variance (AMOVA) indicated the existence of significant genetic variation among the examined host races. Conclusively, analysis using mitochondrial DNA showed an amount of genetic divergence between the two host-associated populations compatible with cryptic species rather than host races.

The larvae of the legume pod borer, Maruca vitrata (Lepidoptera: Pyralidae), cause severe damage on economically important legume crops in the tropics. The female moth produces volatile components to attract males for mating. The so-called sex pheromones are species-specific multi-component blends and are used as lures in crop protection for pest monitoring. Their chemical identification and ratios is critical to design efficient lures. The following sex pheromone components for M. vitrata have been described: (E, E)-10,12-hexadecadienal (major compound), (E, E)-10,12-hexadecadienol and (E)-10-hexadecenal (minor components). The ratio of 100:5:5 of these components was the most attractive in trapping experiments in Benin, Africa. According to this ratio, a synthetic pheromone lure was developed for commercial use. But the commercially available blend was not attractive in field trapping experiments in other regions of sub-Saharan Africa and Southeast Asia. These findings lead to the conclusion that there is a possible polymorphism in the blend composition of the M. vitrata sex pheromone among populations from different geographical regions. In Taiwan, M. vitrata moths were never caught efficiently by the commercially available pheromone lures and traps. This paper reports trap and lure optimization experiments for effective trapping of Taiwanese M. vitrata moths in different leguminous crops.

Conogethes punctiferalis (Crambidae: Lepidoptera) is an important pest of castor, Ricinus communis. The Conogethes species population infesting cardamom, Elettaria cardamomum in India was earlier thought to be C. punctiferalis. This is because moths of both populations appear similar in morphology, particularly wing patterns and colour. The moths too showed a differential response to the sex pheromone components viz. (E)-10-hexadecenal (E10–16: Ald), (Z)-10-hexadecenal (Z10–16: Ald) and hexadecenal (16: Ald) when exposed in castor and cardamom fields. This elicited a doubt that the pheromone composition of castor and cardamom populations might be different. Therefore investigations using Electroantennogram (EAG) and wind tunnel bioassays of populations on castor and cardamom were conducted. Conogethes reared on castor (CBR) had greater EAG response than the one reared on cardamom (CBE) to E10–16: Ald+ Z10–16: Ald mixed in 1: 1 (0.96±0.025 mV). However, CBE elicited highest response to E10–16: Ald+ Z10–16: Ald at 100: 8 (1.10±0.25 mV). In comparative EAG studies both populations gave higher responses to respective female abdominal gland extracts. Wind tunnel bioassay of synthetic pheromone blend E10-6: Ald+ Z10–16: Ald+ 16: Ald (100: 8: 16) showed source contact when tested against males of CBR, contradictory to CBE. The experimental results revealed that the major pheromone component of both the populations was E10–16: Ald but differed in minor components and their proportions. Supportive data on other aspects of the two populations suggested that these are different and could be different species.

Shoot and fruit borer, Leucinodes orbonalis is an important insect pest infesting brinjal or eggplant in India. Molecular characterization of nine different populations belonging to various brinjal growing regions was done using Cytochorome C Oxidase I (COI) gene. Nucleotide analysis of genetic diversity and phylogenetic analysis of the COI indicate that the L. orbonalis from different geographical regions are homogenous. The results showed less nucleotide diversity (π = 0.007895) and overall mean distance (0.008 ± 0.003). Topologies of neighbour-joining (NJ) trees indicate all the populations belong to single major clade. Therefore, it is inferred that there was no significant molecular diversity within L. orbonalis of different geographical locations of India with respect to COI.

Insect pheromones can be used to monitor, mass-trap, and/or disrupt the mating process of insect pests. Sex pheromones of major lepidopteran pests such as tomato fruit worm (Helicoverpa armigera) and common armyworm (Spodoptera litura) are widely used as monitoring lures in tropical vegetable production systems. The use of sex pheromone traps as a mass-trapping tool against polyphagous insects is limited. However, such traps are highly effective in reducing the damage and yield losses caused by monophagous insects such as eggplant fruit and shoot borer (Leucinodes orbonalis), as demonstrated in the Indo-Gangetic Plains of South Asia by AVRDC—The World Vegetable Center. By definition, pheromones are species-specific, yet “cross-talks” were observed when we attempted to refine sex pheromones for monitoring and mass-trapping legume pod borer (Maruca vitrata) and cucumber moth (Diaphania indica). In addition to sex pheromones, the possible use of aggregation pheromone as a pest management tool has been attempted in striped flea beetle (Phyllotreta striolata) on vegetable brassicas. Recent research indicated that pheromones act synergistically when combined with host plant volatiles, a process validated against P. striolata at AVRDC.

Binary NiAl suffers from a lack of strength and poor creep properties at and above 1000 K. Poor creep resistance in turn affects low cycle fatigue (LCF) lives at low strain ranges due to the additional interactions of creep damage. One approach for improving these properties involves microalloying with either Zr or N. As an integral part of a much larger alloying program the low cycle fatigue behavior of Zr and N doped nickel aluminides produced by extrusion of prealloyed powders has been investigated. Strain controlled LCF tests were performed in air at 1000 K. The influence of these microalloying additions on the fatigue life and cyclic stress response of polycrystalline NiAl are discussed.