Species of Oligonychus infesting date palm cultivars in the Southern Arava Valley of Israel

Phytoparasitica (Impact Factor: 0.68). 01/2003; 31(2):144-153. DOI: 10.1007/BF02980784

ABSTRACT In a study of date fruit damage caused byOligonychus spp., we investigated whether the cultivar affects phenology, and on what hosts the mites over-winter. Samples were taken
from ‘Deglet Noor’, ‘Barhi’ and ‘Medjool’ trees from mid-April through mid-September during the years 1999–2002. In the ground-cover
mites were monitored by collecting Bermuda grass (Cynodon dactylon) under each sampling tree. Over 99% of the mites collected on Deglet Noor and Barhi fruit were identified asO. afrasiaticus. Mean population levels ofO. afrasiaticus reached ten mites or more (initiation of infestation) on Medjool in the second half of May, whereas on Deglet Noor this did
not occur before the first week of July. On Barhi the initiation of infestation varied between plots and years, ranging from
the second half of May to the beginning of July, but always occurred earlier than Deglet Noor. Mite populations on the pinnae
remained low from June through October, not exceeding seven mites per pinna, whereas on fruit strands they reached peak populations
of approximately 4000 mites per strand. The sex ratio (proportion of females) ofO. afrasiaticus on fruit of all three cultivars was highly female-biased, usually above 0.85. During winter,O. afrasiaticus was found on Bermuda grass in the orchard ground-cover as well as on fronds of all three cultivars.

Download full-text


Available from: Eric Palevsky, Feb 27, 2014
1 Follower
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An annotated list and key to twenty four species of spider mites (Prostig-mata: Tetranychidae) known from Israel is provided. About half of the spe-cies are considered to be exotics, having invaded Israel within the last fifty years. Nine species, all of which belong to the subfamily Tetranychinae: Eutetranychus orientalis, Eutetranychus palmatus, Oligonychus afrasiat-icus, Oligonychus perseae, Panonychus ulmi, Panonychus citri, Schizo-tetranychus asparagi, Tetranychus turkestani and Tetranychus urticae, are agricultural pests, whereas the others have little economic impact, or else are controlled by their natural enemies.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Several mite species commonly attack cultivated citrus around the world. Up to 104 phytophagous species have been reported causing damage to leaves, buds and fruits, but only a dozen can be considered major pests requiring control measures. In recent years, several species have expanded their geographical range primarily due to the great increase in trade and travel worldwide, representing a threat to agriculture in many countries. Three spider mite species (Acari: Tetranychidae) have recently invaded the citrus-growing areas in the Mediterranean region and Latin America. The Oriental red mite, Eutetranychus orientalis (Klein), presumably from the Near East, was detected in southern Spain in 2001. The Texas citrus mite, Eutetranychus banksi (McGregor), is widely distributed in North, Central and South America. It was first reported in Europe in 1999 on citrus in Portugal; afterwards the mite invaded the citrus orchards in southern Spain. In Latin America, the Hindustan citrus mite, Schizotetranychus hindustanicus (Hirst), previously known only from citrus and other host plants in India, was reported causing significant damage to citrus leaves and fruits in Zulia, northwest Venezuela, in the late 1990s. Later, this mite species spread to the southeast being detected on lemon trees in the state of Roraima in northern Brazil in 2008. Whereas damage levels, population dynamics and control measures are relatively well know in the case of Oriental red mite and Texas citrus mite, our knowledge of S. hindustanicus is noticeably scant. In the present paper, information on pest status, seasonal trends and natural enemies in invaded areas is provided for these species, together with morphological data useful for identification. Because invasive species may evolve during the invasion process, comparison of behavior, damage and management options between native and invaded areas for these species will be useful for understanding the invader's success and their ability to colonize new regions.
    Experimental and Applied Acarology 11/2012; 59(1-2). DOI:10.1007/s10493-012-9635-9 · 1.82 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The biology and ecology of the date palm mite O. afrasiaticus have been studied through regular inspection in Tunisian oases and laboratory observations. Results indicate that the start date of fruit infestation varied between years and by date palm variety. Start dates ranged from the first week to the third week of July. The period spent by the mite on fruits varied from one variety to another; lasting 8 weeks on the Deglet Noor variety, 2 to 5 weeks on Alig, 2 to 4 weeks on Kentichi dates, and 2 to 4 weeks on Bessr fruits. The Deglet Noor variety was the most susceptible to O. afrasiaticus. Mite populations on the pinnae remained low from May through December. During autumn and spring, O. afrasiaticus was found on sorghum leaves in the orchard ground-cover. A life table study in the laboratory at 27°C on six host plants (fruits of date palms varieties Deglet Noor, Alig, Kentichi, Bessr, and Deglet Noor pinnae and sorghum leaves) showed that the life cycle of O. afrasiaticus differed among host plants with average values ranging between 13 on Alig fruits and 10.9 days on sorghum leaves. Relatively high fecundity was found on sorghum leaves (2 eggs/female/day) during 5.2 oviposition days, while low fecundity values occurred on Deglet Noor pinnae and Alig fruits with 0.7 eggs/ female/day during 5.4 days. Average longevity of O. afrasiaticus females ranged from 13.4 to 7.5 days on Deglet Noor fruits and sorghum leaves, respectively. Intrinsic rate of increase (rm) was highest on sorghum leaves (0.171) and Deglet Noor fruits (0.166), and lowest on Alig fruits (0.103). Greater knowledge of life history traits and seasonal abundance of this species is needed in order to design appropriate control strategies. Key-Words: Intrinsic rate of increase (rm); Date palm; Southern Tunisia; Deglet Noor; Seasonal abundance.
    Papeis Avulsos de Zoologia 10/2012; 52(10):121 -131. DOI:10.1590/S0031-10492012001000001