Life history studies of the leafminer Liriomyza trifolii on susceptible and resistant cultivars of Dendranthema grandiflora

Chrysanthemum [Chrysanthemum 9 morifolium Ramat. (Asteraceae)] is one of the economically most important greenhouse ornamentals worldwide. A major constraint in chrysanthemum production is adequate pest management, requiring the use of different tactics, such as improving host plant resistance, in the framework of an integrated pest management (IPM) approach. In this study, we investigated cross-resistance of chrysanthemum to its three major pests: western flower thrips [Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)], celery leafminer [Liriomyza trifolii (Burgess) (Diptera: Agromyzidae)], and two-spotted spider mite [Tetranychus urticae Koch (Acari: Tetranychidae)]. We quantified resistance to each pest by performing greenhouse bioassays with a broad range of chrysanthemum types from commercial germplasm provided by Dutch breeding companies. Considerable variation was detected among the chrysanthemum cultivars in thrips silver damage and growth damage, leafminer damage, measured as number of mines and pupae, and spider mite numbers and damage. We observed significant positive correlations between thrips damage (both silver and growth damage) vs. leafminer numbers (both mines and pupae), and between leafminer numbers (both mines and pupae) vs. spider mite numbers. Our results indicate an overlap in resistance to all three herbivores. The important implications of this result for chrysanthemum breeding are discussed.

Section: Discussionmentioning

confidence: 99%

Cross‐resistance of chrysanthemum to western flower thrips, celery leafminer, and two‐spotted spider mite

Kos

Klinkhamer

Leiss

2014

“…Mayhew (2001) has also presented evidence against the oviposition preference–offspring performance theory. According to DeJong & Rademaker (1991) and Hawthorne (1998), larval survivorship and egg‐adult development time are the most important host‐plant related sources of fitness variation in Liriomyza trifolii . The results of the present study suggest that selection pressure and evolution of the ovipositional preference exhibited by L. trifolii adults for the older, larger, thicker leaves of the potato plant may be dictated by factors other than resource quality for larvae, such as easier feeding and oviposition conditions, increased longevity and fitness for adults, at the expense of maximum nutritional/chemical suitability for larval development.…”

Section: Discussionmentioning

confidence: 99%

Leaf age and life history variables of a leafminer: the case of Liriomyza trifolii on potato leaves

Facknath

2005

Field observations and laboratory experiments have demonstrated that infestation by the serpentine leaf miner, Liriomyza trifolii Burgess (Diptera: Agromyzidae), begins in the lower leaves of the potato plant, and proceeds through the middle leaves to those of the upper canopy. In choice and no-choice experiments, mated adult L. trifolii females were given access for 48 h to potato plants, and caged on differently aged leaves. The extent of their feeding and oviposition on the 5-7 leaflets of the upper, middle, and lower leaves were recorded. The life history variables of the next generation were estimated: percentage egg hatch, number of mines formed, larval survival, number of pupae formed, size and weight of pupae, percentage pupation, number of adults formed, percentage emergence, size and weight of adults, sex ratio, adult longevity, and their reproductive performance. The results showed that L. trifolii females laid fewer eggs on the upper leaves, which were poor hosts for larvae. However, a comparison of oviposition behavior between the middle and lower leaves showed that the data did not fit the oviposition preference-offspring performance hypothesis, which postulates that females preferentially oviposit on hosts on which larvae perform best. Females exhibited a preference for the larger, older, lower leaves, although the middle leaves were superior for the growth and development of the young stages. It is hypothesized that adult ovipositional preference for the older, larger, and thicker leaves of the lower foliage may be influenced by factors other than resource quality for larvae.

“…Nine of the 21 blocks were harvested six days after introduction of the adult females, before the first thrips larvae had hatched. All leaves were cut from each plant, wrapped in toilet-paper and stored at -20 ~ In order to count the eggs, the leaves were boiled for 6 minutes in water as described by de Jong & Rademaker (1991) for eggs of the leafminer L. trifolii. The eggs turned clearly white and were counted with the aid of a binocular.…”

Section: Genetic Variation In Resistancementioning

confidence: 99%

Genetic variation in chrysanthemum for resistance to Frankliniella occidentalis

Jager

Butôt

Klinkhamer

et al. 1995

In a choice‐experiment, 42 chrysanthemum cultivars were screened for resistance to Frankliniella occidentalis (Pergande). Oviposition preference, two types of feeding damage and thrips numbers per flower were recorded as measures of resistance. A large genetic variation in thrips resistance was found among the cultivars screened. The amount of feeding damage was strongly determined by oviposition preference. Besides, a positive correlation was found between the oviposition preference in non‐flowering chrysanthemums (number of eggs) and flowering chrysanthemums (number of thrips per flower). Thrips feeding on young, developing tissues, causes growth damage because affected cells are unable to expand and leaves become distorted. Thrips feeding on older, expanded leaves causes cells to become filled with air, resulting in ‘silver’ damage. The amounts of growth‐ and ‘silver’ damage were negatively correlated suggesting that thrips chose either young or older leaves to feed on. The order of resistance among cultivars did not change during the experiment. In order to get more insight in resistance mechanisms the influence of some plant‐ and flower characters on resistance was examined. The plant characters height, number of leaves, flower production and flower weight were all negatively correlated with resistance. It is suggested that tall chrysanthemum cultivars with many and large flowers may invest less in defence than smaller cultivars, and therefore are more damaged by thrips.