THE INFLUENCE OF CULTURAL PRACTICE ON POPULATION OF PEA LEAFMINER (Liriomyza huidobrensis) AND ITS PARASITOIDS IN POTATO

Abstract

Pea leafminer (Liriomyza huidobrensis) is the major pest of potato crop in Indonesia. The use of insecticides to control the pest is ineffective and harmful to the natural enemies. The study aimed to find out a promising cultural practice for leafminer management on potato crop. The study was conducted at a farmer's field in Bali in 2004. Potato plants (Granola variety) were grown in a raised-bed plot of 10 m x 1 m. The treatments evaluated were standard cultural practice (C), C plus reflective plastic mulch (RPM) (CM), farmer's practice (F), vermicompost (V), and V plus RPM (VM). All treatments were arranged in RCBD with five replications. From each plot, 10 plant samples were randomly taken to observe the presence of larvae, mines, and adults. Larvae and adults of leafminer and mines were separately counted from the top, middle, and bottom parts of the plant samples. Parasitoids were collected from the infested leaves of the plant samples. Emerged parasitoids were counted and put into vials with 70% ethyl alcohol and then identified. The results showed that the population of adults, larvae of L. huidobrensis, and mines were less in C, CM, V, and VM treatments compared to farmer's practice (F). However, RPM (CM and VM) treatments significantly reduced population of leafminer and mines. The highest population of adults, larvae, and mines on RPM treatment were less than 1.5, 8.5, and 10 per plant, respectively compared to other treatments which were greater than 3.2 for adults, 12.4 for larvae, and 12.7 for mines. Parasitoid population and parasitism level were more in vermicompost treatments (V and VM) compared to other treatments (C, CM, and F). The results showed that application of pesticides was ineffective against leafminer and reduced parasitoid population; in the other hand RPM was effective to control leafminer although the effect on parasitoids was not clear. Parasitoid species that were found associated with potato crop were Hemiptarsenus varicornis, Neochrysocharis sp., and Opius sp. Combination of RPM with standard practice and vermicompost are prospective for leafminer management in potato crop, however, VM is friendlier to environment regarding sustainable agriculture.

The Invasive Liriomyza huidobrensis (Diptera: Agromyzidae): Understanding Its Pest Status and Management Globally

“…is very abundant not only on potatoes, but tomato, celery and uncultivated plants (Suryawan and Reyes 2006). Damage by L. huidobrensis and the incidence of parasitism were highly variable among crops in Indonesia.…”

“…In Indonesia, the most common and abundant parasitoid on potatoes is H. varicornis ( Rauf et al 2000 ), in Bali an Opius sp. is very abundant not only on potatoes, but tomato, celery and uncultivated plants ( Suryawan and Reyes 2006 ). Damage by L. huidobrensis and the incidence of parasitism were highly variable among crops in Indonesia.…”

“…Other species of parasitoids have been increasing in abundance, such as Opius chromatomyiae Belokobylskij & Wharton in highland areas. It is now clear that when L. huidobrensis was accidentally introduced to Indonesia, at least some parasitoids also were introduced ( Suryawan and Reyes 2006 ).…”

Insect left-over substrate as plant fertiliser

“…Vermicompost application can reduce the occurrence of blossom end rot of tomatoes (Surrage et al, 2010). Decreases in pathogens such as nematodes (Renčo and Kováčik, 2015), pea leafminers (Suryawan and Reyes, 2016), and scab (Singhai et al, 2011) have occurred when applied to potatoes.…”