The expression patterns of eight defenserelated genes in the herbivore-infested and jasmonatetreated (jasmonic acid, JA and its derivative MeJA) rice leaves were analyzed using RT-PCR. The results showed that Spodoptera litura Fabricius (Lepidoptera: Noctuidae) herbivory induced the expression of lipoxygenase (LOX) and allene oxide synthase (AOS) genes that are involved in the jasmonate-signaling pathway. Moreover, S. litura damage resulted in the expression of farnesyl pyrophosphate synthase (FPS), Bowman-birk proteinase inhibitor (BBPI), phenylalanine ammonia-lyase (PAL) and other rice defenserelated genes that were also induced by aqueous JA treatment or gaseous MeJA treatment. These indicated that in rice leaves, the JA-related signaling pathway was involved in the S. litura-induced chemical defense. Mechanical damage and brown planthopper (BPH), Nilaparvata lugens (St

It has been suggested that herbivore would react to volatiles produced by herbivore infested plant due to potential change, either positive or negative, in the acceptability of the host plant. This hypothesis was tested for the brown planthopper (BPH) in the laboratory. Sixteen components of the headspace volatiles from rice seedlings with different treatments were collected with SPME and Tenax-TA trap and analyzed with GC and GC-MS. Significant differences in volatile emissions were observed for rice plants with different treatments. Undamaged control plants, mechanically damaged plants and the plants infested by BPH for 1 or 2 d emitted much lower amounts of volatiles compared to the plants infested by BPH for 3 or 5 d. The plants infested by BPH for 3 or 5 d emitted several volatiles that were not detected in undamaged control plants, mechanically damaged plants or the plants infested by BPH for 1 or 2 d. Spodoptera litura infested plants released much higher amounts of volatiles than those in all other treatments, and the contents of several green leaf volatiles, methyl salicylate and terpenoids increased dramatically. In dual-choice flight tunnel experiments, adult BPH females showed no significant preference between the untreated healthy plants and mechanically damaged plants or the plants infested by BPH adult females. However, rice plants damaged by S. litura had a clearly repellent effects on BPH adult females compared to healthy undamaged plants, mechanically damaged plants or the plants infested by BPH.

The quality of Trichogramma brassicae Bezd. (5T. maidis n. sp.) (Hymenoptera: Trichogrammatidae) produced in 1998 and 1999 by four companies (AMW Nuetzlinge GmbH, Biocare GmbH, BASF, and Landi) to control the European corn borer Ostrinia nubilalis Hubner (Lepidoptera: Pyralidae) was measured. Standard methods developed by the International Organization for Biological Control (IOBC) were used to assess sex ratio, number of females released per hectare, longevity, fecundity, and capacity to parasitze the natural host. The percentage of females was between 50.7 6 1.5 and 68.3% 6 1.9%, always higher than the 50% standard agreed upon by the IOBC. The number of parasitized eggs released per hectare was, with one exception, considerably higher than the standard of 100,000 given by the companies. In five cases, it was over 150,000 parasitized host eggs per hectare. The emergence rate varied from 72.3 6 1.3 to 90.6 6 0.9%. Therefore, the number of females released per hectare varied between 38,532 and 86,966. The survival rate (to day 7) fluctuated between 16.7 and 66.7% and was much lower than the optimistic IOBC standard of 80%. The fecundity on the mass rearing host Sitotroga cerealella (Olivier) and on the target host O. nubilalis was also often lower than the IOBC standards, and this especially in the first release, which could partly be due to longer storage. The releasing units contained parasitoids in different development stages to prolong the period of adult emergence and thereby extend the duration of treatment. Parasitoid emergence for the two treatments together continued for about 4 weeks (June 30 to July 27, 1998, and June 23 to July 21, 1999). In both test years, the two parasitoid releases produced strongly overlapping periods of adult emergence that coincided with the egg-laying peak of the pest in the field.