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العنوان
Safe control of terristrial snails in Sugar beet (Beta vulgaris )
At Kafr
El - Sheikh Governorate
المؤلف
Idrees,Nadia Mohamed Mostafa.
هيئة الاعداد
باحث / Nadia Mohamed Mostafa Idrees
مشرف / Gamal Abd El -Sattar El –Kady
مشرف / SaiedAbdl -Latief Dahrou
مناقش / Ahamed Eid Abdel- Megeed Mahgoob
تاريخ النشر
2014.
عدد الصفحات
150P.:
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
علوم البيئة
تاريخ الإجازة
1/1/2014
مكان الإجازة
جامعة عين شمس - معهد البيئة - قسم العوم الزاعية
الفهرس
Only 14 pages are availabe for public view

from 120

from 120

Abstract

1. Abundance and food behaviour 0f land snails associated with sugar beet crop :
1.1. Survey 0f c0mmon land snail species :
Survey results of terrestrial snails infesting field crops, sugar beet (Beta vulgaris) at
El-Hamool, Quallien and Sakha districts, Kafr El-Sheikh Governorate during the period from
October to May during the two successive seasons 2008/2009 and 2009/2010, proved the occurrence of
two herbivorous snails belonging to the Family Helicidae which represented by two species of the
i.e M . cantiana (Montagu) and C . acuta (Muller).
The distribution and infesting levels of the surveyed land snail varied according to localities
whereas M . cantiana snails were recorded in all surveyed localities, attacking several host
plants including sugar beet plants as a field crops.
M . cantiana snails were found with heavy infestation on sugar beet plants at all the surveyed
districts. C . acuta snails were found with heavy infestation on sugar beet plants in fields which
surrounded by Casuarina equistifolia trees and the plantation which found beside Trifolium
alexandrinum at Sakha and Quallein districts. Also, C . acuta snails were found with
moderate infestation at all surveyed localities, especially in sugar beet fields at El-Hamool
district. S . putris snails were found in moderate infestation on sugar beet at Sakha and Quallein
and in heavy infestation on vegetables which surrounded by sugar beet fields.
1.2. Population dynamics as affected by timming of plantation :
The population dynamics of the predominant snail species on the economic crop, sugar beet were
studied at Sakha, Quallein and El-Hamool districts during the period from October to May during
the two successive seasons 2008/2009 and 2009/2010.
Data revealed that snails population density reached their maximum and minimum values on sugar beet
plants for M. cantiana
, C. acuta and S . putris.
At El-Hamool district, M . cantiana snails were recorded in
November in first and second plantation in light infestation (4.3 and
6 snails/plant),while population density recorded maximum values
(24.1, 51.9 and 77 snail/m2) in March, April and May during the 1st ,
2nd and 3rd plantations. C . acuta snails were recorded in light infestation (19 and 15.3
snail/m2) during December in the 2nd and
3rd plantations and recorded (36.8 and 16.4 snail/m2) during April in
2nd and 3rd plantations during the first season 2008/2009.
S . putris snails were found on sugar beet plants in Decembedr in values (32.2 and 19 snail/m2) in
first and second plantations. The maximum numbers were in April (24 and 19.8 snail/m2) in the 2nd
and 3rd plantation at the same season 2008/2009.
In the second season, 2009/2010, the average numbers of snails were (14.1 and 14.8
snail/m2) in November during 1st and 2nd plantation for M . cantiana and reached maximum
values (42.8,
53.8 and 34.4 snail/m2) in March, April and May, respectively. On
the other hand, C .acuta snails were found only in January in
moderate infestation(14.1, 19 and 16 snail/m2) during the1st , 2nd
and 3rd plantations, respectively and recorded high infestation (61 and 59 snail/m2) during
April in 2nd and 3rd plantation. Also, S. putris snails were found in light infestation on
sugar beet in 1st and 2nd plantation (16 and 7.9 snail/m2) and reached maximum values (26, 26
and 41 snail/m2) during April in 1st ,2nd and 3rd plantations.
Regarding the population dynamics of M . cantiana , C . acuta
and S . putris on sugar beet plants at Qualein districts 913.9 and
15.3 snail/m2) during December in 1st and 2nd date of planting for M . cantiana snails,
while the population was 12 and 19 snail/m2 during the same mouth for C . acuta and S . putris in
the 1st date of planting. The maximum numbers of the three species of snails were (36.6 and
26.6), (63 and 31) and (53 and 36 snail/m2) during April season 2008/2009.
Population of M . cantiana was 15.1 and 14.7 snail/m2 during November in 1st and 2nd date of
planting and the snail S . putris was recorded in few numbers 23 snail/m2 only in the 1st date
of planting, while the conical snail C . acuta was not recorded in this time. The maximum of
numbers of the three species were in April (25.1 and
38.3 snail/m2), (54 and 38 snail/m2) and (64 and 29 snail/m2) in the
second and third date of planting during season 2009/2010.
On the other hand, M .onacha cantiana snails were recorded in 1st and 2nd date of planting
during December (11.9 and 12.3 snail/m2) while C. acuta and S. putris were not recorded in this
time
of season 2008/2009 at Sakha district. The maximum of values were
recorded (59.7 and 66 snail/m2), (49 and 29 snail/m2) and (29, 46 and 39 snail/m2) for M.
cantiana , C. acuta and S. putris, respectively. Also, only M . cantiana snails were
recorded in 1st and 2nd date of planting during December, while the maximum values were
(41.6, 34.7 and 80 snail/m2) for M. cantiana during March, April and May, respectively. C . acuta
reached maximum values in April (26 and 29 snail/m2) in 2nd and 3rd date of planting, while S .
putris reached maximum during April (31, 26 and 20 snail/m2) in the first, second and third date of
planting during season
2009/2010 at Sakha district, Kafr El-Sheikh governorate.
Regarding the correlation between population density and climatic factors, it is clear that
temperature and relative humidity did not show variable effects on population density of the tested
snails.
1.3. Food preference:
Laboratory experiments had been conducted to study the food preference and consumption of M
.cantiana snails. Leaves of sugar beet were the most preferable food to the snail, followed by
lettuce leaves and cabbage. Onion and garlic leaves were the most repellent food to snail due to
test and odor. Bran was the most preferable (74.2 mg/individual) followed by crushed wheat (69.6
mg/individual) and crushed bread (41.4 mg/individual), while crushed rice was the lowest (16.8
mg/individual). Bran with molasses as attractive material was the most preferred (138
mg/individual) followed by bran with vanilla (93 mg), while bran with garlic and onion juice were
the lowest (7.9 and 31.8 mg/individual).
1.4. Damage assessment due to snails:
Data indicated that different levels of M .cantiana snails caused damage to sugar beet
plants. The loest reduction were 68 gm with average percentage23.94% in shoot whereas 80 gm with
apercentage 9.19 % in roots at the infestation level 10 snails / plant comparing with the control .
On the other hand ,the highest reduction were 135 gm with a percentage47.53 %in shoot whereas156 gm
with apercentage 17.93% in root at the infestation level 50 snail /plant . Generally , slightly
differentation between the levels 20 and 30 snail
/plant . the mean of reduction in shoot weight were 96.8gmwith apercentage 34.08 in shoot and 106
8 gm with apercentage 12.23 in roots comparing to the control .
2. Control studies
2.1. Laboratory experiments:
2.1.1. Poison bait technique:
Protecto could be arranged according to the order of activity against M. cantiana and C. acuta in
descending order 3.1 ppm and
2.92 ppm. Bioranza was the most toxic action against M. cantiana and C. acuta, LC50 4.01 and 4.96
ppm, respectively, while spinosad gave 4.6 ppm for M. cantiana and 14.3 ppm. C . acuta snails were
the most sensitive to protecto than M .cantiana . On the other hand, M. cantiana snails were the
most sensitive to Bioranza and spinosad
4.01and 4.6 ppm than C. acuta 4.96 and 14.3 ppm.
2.1.2. Dipping technique:
Results of these studies show the sensitivity of C . acuta to Spinosad LC50 2.6 ppm than M.
cantiana 4 pm, while M. cantiana snails were most sensitivity to protecto and Bioranza LC50 594.9
ppm and 841 ppm than C. acuta LC50 733 and 1054 ppm, respectively.
2.2. Field experiment:
2.2.1. Agricultural practies :
These studies aimed to apply ecological control to reduce or management of population of snails.
The results showed that, soil cultivation, cleaning the soil from the remainders of plants and
ploughing the soil in addition to using seeds treated with Guasho reduce the attack of snails.
After 30 days, intensifying onion and garlic with sugar beet plants greatly reduce the attack of
the snails to more than 50%. Results showed increasing of population of snail M. cantiana and C.
acuta from November and reached its maximum in April, then decreased in May at control area, while
in treated area, their numbers were 143 snail/m2 and the reduction was 35.3% during season
2008/2009. On the other hand, the mean numbers of snails in control area was 174 snail/m2 during
November and reached the
maximum (600 snail/m2) during April comparing with the
population of snails in treatment area, it was129snail/m2 in November and reached
296 snail/m2 in April and the reduction in population reached 51.4% and 72% in May.
Activity of various microbial compounds under field conditions:
-Using a spray method :
Protecto and Bioranza were tested at rate of 125, 250 and 500 gm/200 L water/feddans, while
Spinosad was tested at rate 20, 30,
40 and 50 ml/100 L water/feddans against M .cantiana and C . acuta infesting sugar beet plants
using the spray method that reduced snail population after 15 days of treatment. Results showed
average reduction by (65.9, 47and 44.3%), (30.4, 19.3 and 17.5%)and (45.6,
32.2, 30.6 and 22%) for M. cantiana snails and (43.1, 40.2 and
24.01%), (40.1, 33.6 and 27.4%)and (47.4, 46.4, 16.9 and 7.6%) for
C . acuta during 2009/2010.
- Using apoison baits :
Protecto and Bioranza were tested as a poison baits method at rate of 1.25, 2.5, 5 and 10% and
spinosad was tested at rate of 2, 3, 4 and 5 ml%. The average of snails population reduction after
15 days post treatment were (25.6, 36.7, 56.4 and 66.1%) (9.6, 23, 40.6 and
46.8%) and (15.8, 25.7, 29.4 and 54.5%) for M. cantiana and (14.8,
28, 32.6, and 54%), (3, 13.7, 31 and 40.2%)and (6.8, 22, 25 and
29.3%) for Cochlicella acuta snails during 2009/2010 season.
In conclusion, control responsible and/or the farmer must be taken into account, two important
factors, where and when mollusciciding operations were carried out during the course of the present
study. It is interesting to notice that terrestrial snails were active only after irrigation, in
moist weather, in damp evening and
early morning hours. It is thus under these circumstances that snails
can come into contact with molluscicides. Also, the density of snails population are increase at
field edges, specially beside field water canals, in tall herbs and under weeds which covering
pontes, therefore, focal/seasonal mollusciciding operations are likely to be the role rather than
blanket (=area wide) applications.
Also, the present study indicate that application Ecological and Biological Control play an
important role in depressing the population numbers of snail infestation, minimize the
environmental pollution.