Host Plant Resistance in Cultivated Jute and Its Wild Relatives Towards Jute Hairy Caterpillar Spilosoma obliqua (Lepidoptera: Arctiidae)

Abstract

The oviposition, feeding behavior, and development of the jute hairy caterpillar Spilosoma obliqua Walker (Lepidoptera: Arctiidae) was studied on one cultivated jute species, Corchorus olitorius L. ('JRO-204') (Malvales: Malvaceae), and 5 wild jute species, viz., C. tridens L., C. trilocularis L., C. pseudo-olitorius Islam & Zaid, C. aestuans L., and C. fascicularis Lamarck under laboratory conditions with a temperature of 27 ± 2 °C and relative humidity of 80 ± 5%. These host plant species had considerable influence on oviposition, larval feeding behavior, larval survival, larval weight, pupation, pupal weight, and adult emergence. Significant differences were observed in oviposition preference based on numbers of eggs laid by the adults. The mean number of egg clusters differed significantly with 3.6 ± 0.3, 3.0 ± 0.6, 3.3 ± 0.3, 3.0 ± 0.6, 1.0 ± 0.6, and 2.0 ± 1.2 on C. olitorius, C. fascicularis, C. trilocularis, C. pseudo-olitorius, C. tridens, and C. aestuans, respectively. The C. pseudo-olitorius and C. aestuans were less preferred with the lowest mean numbers of eggs per cluster (77.2 ± 8.2 and 75.2 ± 38.8, respectively) compared with 174.0 ± 2.7 on C. olitorius. With respect to feeding preferences, most larvae (53.9 ± 3.4%) preferred C. olitorius as compared with 1.6 ± 0.02% and 7.2 ± 1.5% of larvae feeding on C. aestuans and C. tridens, respectively. Only 2 species, namely C. trilocularis and C. olitorius, supported complete larval development. The growth of 3rd instars indicated a maximum antibiosis effect by C. tridens and C. aestuans on S. obliqua. Total protein content in the host plants had a significant positive correlation with the larval survival, weight, pupation, and adult emergence of S. obliqua, whereas polyphenol oxidase and total phenol were negatively correlated. The effect of wild jute species with higher phenol and peroxidase as host plants manifested adversely on larval development, growth, survival, pupation, and adult emergence, which indicates the antibiosis mechanism of resistance.