Dryinid parasitoids of rice leafhoppers and planthoppers in the Philippines II. Rearing techniques

Abstract

Three new techniques of rearing dryinids parasitising rice hoppers were developed, namely, laboratory rearing technique for detailed observations, device for transporting and rearing field-collected hoppers to estimate percentage parasitism and a breeding technique.Satisfactory techniques for studying dryinids' behavior and development or for rearing field-collected hoppers were not available to date. In most cases, studies were made in Petri dishes and glass tubes containing host plant, which proved unsatisfactory because of reduced aeration and accumulation of excessive moisture, particularly in tropical climate. Some workers used a smaller tube for holding the plant and a larger one to serve as cover (PAGDEN, 1934; WALOFF, 1975) but the disadvantages described above persisted and, in addition, rearing large number of hosts was still cumbersome. Therefore, 3 new techniques were developed and found satisfactory for conducting various studies on dryinids parasitizing rice leafhoppers and planthoppers. REARING CAGE FOR DETAILED OBSERVATIONSStudies of the biology, behavior and development of dryinids often required close examination through a binocular microscope. A cage was developed in which parasitized hoppers could be reared individually and close observations of larval development as well as feeding and parasitization behavior of the adult could be made.The cage ( fig. 1) was a transparent plastic tube measuring 160 mm x 24 mm and open at both ends. A nylon mesh was fixed on the upper end of the tube for aeration. One or 2 small holes were made on the sides of the cage for inserting aspirator. These holes were plugged with cotton. A rubber stopper which fits in the lower end of the cage was especially cut and bored to hold the roots of the rice plant while the aerial parts remained (1) Present address :

The strepsipteran parasite Elenchus japonicus (Strepsiptera, Elenchidae) of planthoppers consists of three genotypes

“…E. japonicus parasitization has been reported in Japan, the Philippines (Barrion and Litsinger 1987;Yano and Kifune 1994) and on the East China Sea (Kifune and Maeta 1986;Kifune 1986;Kitamura and Nishikata 1987;Halbert et al 2001;Maeta et al 2007). In contrast, E. yasumatsui parasitization has been described only in southern Asia (Kifune and Hirashima 1975;Chandra 1978;Hirashima et al 1979;Chandra 1980;Barrion and Litsinger 1987). The present results seem to indicate that E. yasumatsui may indeed be a different species from E. japonicus, but that one of the genotypes of E. japonicas, plausibly the TA/mt2 type, may be related to E. yasumatsui.…”

“…E. japonicus parasitizes many delphacid planthopper species, including the rice planthoppers Nilaparvata lugens (Stål) (brown planthopper, BPH), Sogatella furcifera (Horváth) (white-backed planthopper, WBPH) and Laodelphax striatellus Fallén (small brown planthopper, SBPH) (Chandra 1978(Chandra , 1980Kifune and Maeta 1986; Electronic supplementary material The online version of this article (doi:10.1007/s13355-011-0060-z) contains supplementary material, which is available to authorized users. Barrion and Litsinger 1987;Carcupino et al 1998).…”

A review of the biology of the pincer wasps (Hymenoptera: Dryinidae)

“…According to Mora-Kepfer and Espinoza (2009), the behaviour of females of H. hernandezae as predators and parasitoids promotes a stable control of the planthopper Tagosodes orizicolus (Muir) in Costa Rica. However, some pincer wasp species are not thought to play a significant role in controlling leafhopper and planthopper populations that live in rice field in Asia (Chandra 1980), acidic grasslands in England (Waloff 1975(Waloff , 1980 or Bermuda grass in Georgia (USA) (Buntin 1989).…”

The Use and Benefits of Bacillus Based Biological Agents in Aquaculture

“…The use of CSL resulted in a higher spore concentration, productivity and spore yield on protein, in comparison to yeast extract and nutrient broth. Apart from the nature of protein source, the protein concentration in culture media also affects growth and spore production [155]. B. subtilis spore productivity increased, but spore yield decreased, with an increase in CSL concentration [149].…”