The exploitation of the suitable major food plants for increasing eri cocoon yields

Abstract

Eri silkworm production as textile and raw material for consumption (pupa) was principally focused on cocoon production. The major 4 important types of eri silkworm food plants, castor TCO101, castor CaKKU1, cassava Rayong 72 and Kesseru (Thai Line) were tested on feeding of eri silkworm IPKKU1 ecorace. Feeding food plant to eri silkworm composed of 8 treatments, castor TCO101, castor CaKKU1, cassava Rayong 72, Kesseru, castor TCO101 alternated with Rayong 72 every other day, castor TCO101 + Rayong 72, castor TCO101 (1^st-4^th instar) + Kesseru (5^th instar) and cassava Rayong 72  (1^st-4^th instar) + Kesseru (5^th instar). The result showed that feeding with only cassava Rayong 72 led to the highest average cocoon yields of all components: fresh cocoon weight, pupa weight, shell weight, % shell and total cocoon shell weight with values of 2.4447 g, 2.1092 g, 0.3157 g, 12.97% and 31.26 g, respectively. In addition, to select the suitable treatments (each main food plant / combined food plants), it could be evaluated from important average cocoon yields (fresh cocoon weight, pupa weight and total cocoon shell weight). However, this study suggests that the cassava Rayong 72 is one of the suitable main food plants of eri silkworm especially in the northeast of Thailand.