| Titles |
|
English :
|
Studies on insect pests of some solanaceous vegetables
|
|
Arabic :
|
دراسات علي الآفات الحشريه لبعض خضروات العائله الباذنجانية
|
|
| Abstract |
The Solanaceous plants, potato and tomato are two principal vegetable crops in Egypt. Plants of the two crops are infested with considerable numbers of economic important insect pests particularly those which are ideal vectors for viruses causing plant diseases. Therefore the present work was carried out to study the following points.
Insect species associated with potato and tomato plants:
Survey of insects associated with potato was carried out at Mehalla El-Koubra in summer and winter plantations in farmer's fields in 1991. Survey of insects associated with tomato was conducted in Kafr El¬Sheikh in summer and Nili plantations in farmer's fields as well as under plastic tunnels in season 1991/92. Obtained results can be summarized as follows :
1- Insect survey indicated the occurrence of 14 species of insect pests and predacious natural enemies belonging to 10 families from 5 orders on potato plants and 9 species of insect pests and predacious natural enemies belonging to 8 families from 5 orders. On tomato of plastic tunnels, five species of insect pests belonging to four families from two orders were surveyed.
2- The most dominant insect pests on potato and tomato plants were the homopterous sap sucking species, where they formed 98-99% of insects occurred on potato plants and 86.4-94.2% insects occurred on tomato plants in the field. Homopterous insects formed 92.3% of the total insects surveyed on tomato plants under plastic tunnels.
3- The most dominant: insect pests on potato and tomato plants were Bemisia tabaci, Aphis gossypii, Myzus peNSicae and Empoasca decipiens.
II- Population abundance of dominant insect pests :
The population abundance of B. tabaci, A. gosypii, M.pensicaeand E. decipiens were studied on potato at Mehalla El-Koubra in summer and winter plantations of season 1992/93 and on tomato at Kafr El-Sheikh in summer and Nili plantations of season 1992. The population abundance of the insects was also estimated on tomato under plastic tunnel. The obtained results can be summarized as follows :
1- On potao plants, the most abundant insect was M. persicae with the highest peak on 8ffi of April (307 adults/60 1eaflets) followed by A. gossypii, B. tabaci and E. decipons m summer plantation while in winter plantation, the most abundant insect was B. tabaci with the highest peak on 21t' of November (2656 adults/60 leaflets) followed by E. decipiens and M. persicae.
2- On tomato plants, the most abundant insect was B. tabaci with the highest peak on 4th of August (3 11 adults/60 1eaflets) followed by A. gossypii, E. decipiens and M. persicae in summer plantation. In Nili plantation, the most abundant insect was B. tabaci with two peaks in the 3rd week of August and 2nd week of September followed by A. gossypii and M. persicae, while E. decipiens was not recorded.
3- On tomato under plastic tunnels, the most abundant insect was B. tabaci with highest peak (318/60 leaflets by mid June) followed by A. gossypii and M. persicae.
III - Role of hompterous insects in transmission of some potato and tomato diseases:
The study was carried out in different localities in season 1993/94 to survey the most distributed plant diseases in potato and tomato fields. A monthly visit was made in farmer's fields and diseased plants were examined and symptoms were described and registered by photos. In heavily infected area, B. tabaci, A. gossypii, M. persicae and E. decipiens were collected. In the laboratory, individuals of each species were released on healthy plants reared in the laboratory. The plants were daily observed for recording and describing symptoms appeared on the plants. Obtained results indicated the occurrence of four plant diseases which were found to be transmitted under laboratory conditions, by certain insect species.
1- Potato leaf roll disease (PLRD):
The disease was widely distributed in farmer's fields at Mehalla El¬Koubra on potato plants of Nili plantation. The disease was transmitted by Myzus persicae to healthy potato plants and the symptoms appeared on the plants 25 days after inoculation.
2- Potato virus Y disease (PVYD):
The disease was distributed in the farmer's fields at Mehalla El-Koubra and Kafr El-Zayat where some fields were found completely destroyed by the disease. The green peach aphid, M. persicae was able to transmit the disease under laboratory conditions. The symptoms of the disease were described in the field and in the laboratory.
3- Tomato yellow mosaic disease (TYMD):
The disease was widely distributed in Kafr El-Sheikh and Dessouk.
Symptoms appeared on the plants varied from light yellowing of leaves
to moderate stunting of the plants. The disease was transmitted to healthy tomato plants under laboratory; conditions by the adults of the
whitefly, B. tabaci.
4- Tomato yellow leaf curl disease (TYLCD):
The disease was widespread in many tomato fields at Kafr El-Sheikh and Dessouk. Diseased plants showed purple patches, upward rolling of leaflets, dwarfing and excessive branching. The disease was transmitted under laboratory conditions by adults of B. tabaci.
IV Preference of potato and tomato cultivars to B. tabaci infestation:
Three recommended potato and five tomato cultivars were used to
evaluate their preference to B. tabaci infestation. Preference of the tested
cultivars based on the number of the insect immature stages recieved by
each cultivar plants. The experiment was conducted in the farm of the
faculty in the winter plantation of 1993/94. The obtained results are
summarized as follows:
1- Potato cultivars: Spunta cultivar proved to be the most preferred for
egg-laying and harbouring of larvae, while the highest number of
pupae were recorded for Draga cultivar. Concerning all counted immature stages, spunta cultivar was; the most preferred host (151.1 insects/100 leaflets) followed by Draga (140.2 insects/100 1eaflets) and Diamant (115 insects/100 leaflets).
2- Tomato cultivars: Plants of Castle rock cultivar were the most preferred host for B. tabaci (196 individuals/100leaflets) followed by those of Fresh market (177.8 individuals/100leaflets) and Strain B (106.5 individuals/100 leaflets). The significant least preferred plants were those of Beto 86, since they harboured 66 individuals/100 leaflets.
V- Preference of some vegetables, weeds and hedge plants as hosts of Bemisia tabaci:
Ninteen plant species of vegetables, weeds and perennial plants, which are commonly occurring in and near potato and tomato fields were evaluated as hosts for B. tabaci. Preference of the tested plants passed through the population densities of the immature stages on each plant species in the period from 7h of August to 2nd of October 1994. The obtained results can be summarized as follows :
1- The sweet potato was significantly the most preferred host for egg¬laying (316.7 eggs/30 leaves) followed by lantana (277.3 eggs), egg plant (230.1 eggs) and lofa (197.1 eggs).
2- The pigweed plants harboured the highest number of larvae (74.7 larvae/30 leaves) being significantly different from all other tested hosts, followed by egg plant (58 larvae/30 leaves), lofa and then lantana.
3- Egg plant harboured the highest density of pupae (67.6 pupae/30 leaves) followed by chicory (56.9), cocklebur (51.4), castorbean (47.7), lofa (44.3) and lantana (44.0 pupae/30 1eaves).
4- Considering the total number of immature stages counted on each host plant, the highest population density was recorded for lantana followed by sweet potato, egg plant, lofa, chicory, field bindweed, pigweed, duranta, cocklebur, castorbean, karkade, Jew mallow, march mallow, sorrel, black nightshode, pepper, petty spurge, squash and wild beet.
|
| Publication year |
1990
|
| Availability location |
معهد بحوث وقاية النباتات - ش نادي الصيد - الدقي - الجيزة
|
| Availability number |
|
| Organization Name |
Plant Protection Research Institute (PPRI)
|
| Country |
Egypt
|
| Publisher |
Name:
كليه الزراعه بكفر الشيخ-طنطا
Place:
كليه الزراعه بكفر الشيخ-طنطا-مصر
|
| Author(s) from ARC |
|
| Agris Categories |
Protection of plants - General aspects
|
AGROVOC
TERMS |
Aphis gossypii.
Bemisia tabaci.
Empoasca.
Myzus.
Natural enemies.
Pest insects.
Potatoes.
Tomatoes.
Weeds.
|
| Publication Type |
Master Thesis
|