Scientific research results in pandemic conditions (COVID-19)
22
In Table 2, 30 days before migration, worker bees in the hive gained 6.9
mg or 4.8% of their weight compared to controls. Similarly, 20 days before
the same bees weight, in experimental groups 15.5 mg or 13.5% more than
in the control group.
Conclusion: Before the bee family migrates and separates, it can be
learned based on the physiological changes that take place in the div of
worker bees 20 days before they do so. In migratory families, the size of the
worker bees increases, and the amount of fat in his div increases slightly.
All this is due to the migration of bees that migrate to a new place; they build
a new place, raise a new generation, collect food and process them. In order
to spend the winter well, it fills the hive with young bees and replenishes it
with a large amount of food reserves for a successful winter.
In migratory bee families, worker bees can be identified by physiological
changes in their bodies 30-20 days before the migration.
References:
1.
ÐажÑкин Ð.С. ÐоÑÑба Ñ Ñоением. ж. ÐÑеловодÑÑво, 2011, â4, ÑÑÑ.
34-35.
2.
ÐоÑÑева Ð.Я., ÐозÑб Ð.Ð. ÐÐ·Ð¼ÐµÐ½ÐµÐ½Ð¸Ñ ÑодеÑÐ¶Ð°Ð½Ð¸Ñ Ð²Ð¾Ð´Ñ Ð¸ жиÑа в
Ñеле пÑÐµÐ»Ñ Ð² пеÑиод зимовки. Ð.ÐÑеловодÑÑво, 2011, â1, ÑÑÑ. 16-17.
3.
ТаÑанов Ð.Ф. ÐÐ¸Ð¾Ð»Ð¾Ð³Ð¸Ñ Ð¿Ñелиной ÑемÑи. РоÑÑелÑÑ Ð¾Ð·Ð¸Ð·Ð´Ð°Ñ
ÐоÑква, 1986.
4.
Ð ÑбалÑÑенко Ð.Ð. Ðагадка пÑелиного ÑоÑ. ÐинÑк, «УÑожай»,
1982.
Daniyarov Umirzak Tukhtamuradovich, Tashkent State Agrarian
University, Professor of âSericulture and mulberry growingâ department.
Suvonova Anzura Dusqoraevna, Tashkent State Agrarian University,
assistant of âSericulture and mulberry growingâ department.
Soxibova Nigora Sadritdtnovna, Tashkent State Agrarian University,
Department of âSericulture and mulberry growingâ 2nd year PhD student.
CREATION OF INBRED SYSTEMS WITH A CHOICE OF PLUS AND MINUS ON
THE VIABILITY OF SILKWORMS WITH THE BEST COMBINATION VALUE
Daniyarov U., Suvonova A. , Soxibova N.
Abstract: There is no difference in performance in systems with plus and
minus selection. In the F-1 and F-3 systems where viability plus selection
was performed, cocoon weight values were 1.84 g and 1.85 g, and shell
weights were 432 mg and 422 mg, respectively. In practice, the minus
selection does not differ from those of the conducted F-2 and F-4 systems -
Scientific research results in pandemic conditions (COVID-19)
23
1.72 g and 1.85 g, respectively; 394 mg and 420 mg. Clearly, the choice of
viability leads to the accumulation of recessive hemispheric and subletal
genes in the homozygous state in the system. As a result, some organisms
die at different stages of development. But some of them survive. Probably
on the one hand, because harmful genes are less accumulated, and on the
other hand, because there are enough positive genes to compensate for the
effects of harmful genes, i.e., the GCC is formed.
Had this process not taken place, no doubt the system would have
perished as a result of negative selection over several generations. It follows
that GCC does not occur in systems with high viability. The predominance of
positive genes over negative genes is achieved without them. In addition, the
process of mutation is accelerated under the influence of negative selection.
This increases gene diversity.
Thus, not only the reserve but also the newly emerging genes remain
the source for the blocks of both categories.
Keywords: Inbred, system, top cross, bottom cross, in cross, heterosis,
hybrid, mulberry silkworm, cocoon, cocoon shell, silkworm.
According to many scientists [V.A. Strunnikov, S.V. Nasriddinova, V.N.
Shushikova N 1979,1987], the use of close kinship in the selection and
breeding of mulberry silkworms can increase the homogeneity of cocoons,
increase of silk production and silk raw materials, it also leads to an increase
in the output, an improvement in the cocooning. Therefore, in the selection
and breeding work with mulberry silkworms, research related to the use of
crossbreeding to strengthen the economic-beneficial traits and increase the
effectiveness of heterosis in crossbred hybrids obtained from interbreeding
hybridization of inbred systems is important.
It is well known that heterosis is particularly pronounced when inbred
systems or strains are mixed with inbred systems. We had 4 inbred
generations of silkworms at our disposal, i.e. strong Inbred Line 48, Line 51
systems. Therefore, it was very interesting to determine how hybrids
between inbred systems and Chinese 108 and Japanese 66 breeds manifest
themselves in terms of technological characteristics of cocoon fiber.
The most effective of the interbreeding systems applied to mulberry
silkworms is the mating of blood-siblings, which provides close
homozygosity in the offspring, in our case, on the viability of silkworms.
Selection-inbreeding creates a high degree of phenotypic and genotypic
homogeneity in the offspring across all genetic traits of the organism. Inbred
reproduction, which is carried out by selecting the best creatures and
disposing of the worst, leads to the creation of systems that are resistant,
viable and productive, free from all negative genetic factors.
Scientific research results in pandemic conditions (COVID-19)
24
In other words, the sum of the genotypes of the ancestors of an isolated
breed forms an immutable hereditary fund, and the genotype of the
generations does not go beyond it.
The combination of viability in the mulberry silkworm genotype with
the high-tech properties of cocoon fiber is a noble goal of all silkworm
practitioners.
[Strunnikova L.V., Strunnikov V.A., Sharova I.G., Yakubov A.B., Pashkina
T.A., Larkina E.A., Tadjiev E.X., Ikramov Z.I. 1999.] According to research, one
of the causes of heterosis is the emergence of a positive genes compensatory
complex (GCC) that is formed slowly during inbred reproduction and resists
inbred depression. In inbred systems, the choice for both high viability and
low viability is the mechanism that triggers the formation of GCC.
There is no official data on the reaction of large cocoon breeds to inbred
breeding, so the study of the possibility of using inbreeding in the breeding
of high-yielding breeds created by synthetic methods will undoubtedly be of
interest, as it is planned to introduce such breeds in Uzbekistan.
Large cocoon selection systems Line 48 and Line 51 were used as
experimental material. Through the Sister to Brother hybridization, each
selection system was previously fitted with two inbred systems: F-1 and F-
2 from Line 48, and F-3 and F-4 from Line 51 systems, the selection was
made on the increased viability of silkworms, and on the F-2 and F-4 systems
- on the reduced viability. In this study, five inbred generations (J5, J6, J7, J8,
J9) were studied and the response of the strains to inbreeds in systems with
targeted selection was determined. The control was provided by silkworms
obtained by outbred crossbreeding of the same species. The results of the
study are presented in Table 1.
Table 1 clearly shows the inbred depression of the F-1, F-2, F-3, and F-4
systems in terms of the number of normal eggs in the stock, the weight of
the stock, and the weight of a single egg. For example, Line 51 has 711 eggs,
while the F-1 and F-2 inbred systems derived from it have 637 and 646 eggs,
respectively. The average weight of one egg in line 48 is 0.587 mg. In F-3 and
F-4 inbred systems derived from it - egg weight was 0.587 and 0.549 mg.
Inbred breeding has led to a certain stabilization of the reproductive traits
of the breed. The coefficient of variation was found to decrease at the end of
inbredization of all parameters in all inbred systems. In the F-1 system, the
Sv in normal seeds in terms of quality was 18.6% in 2007 and -14.8% in
2011. A similar situation was observed in other systems. The confidence
level (Pd = 0.999) for egg resuscitation was calculated.
However, there is almost no difference in reproductive performance
between inbred systems with high and low viability of silkworms. This can
be explained by the fact that there is little or no correlation between the
viability of silkworms in Line 48 and Line 51 and the amount of eggs in the
Scientific research results in pandemic conditions (COVID-19)
25
nest. In that case, survival selection cannot lead to a significant change in
reproductive traits, and we see this in this experiment.
Scientific research results in pandemic conditions (COVID-19)
26
Table 1
Reproductive and hatching indicators of inbred systems (2007-2011
years)
Table 2
Biological indicators of selection inbred systems (2007-2015 years)
*Pd=0,999
In this breed, the correlation between the viability of silkworms and the
number of eggs in the nest was very low and was 0.041. The correlation
between survival and weight of a single egg - 0.126 is also the result of
research [Nasirillaev U.N. 1985.]. Inbred depression significantly bypassed
egg hatching (Table 1).
From the researches of the Turkmen scientist [Mamedov A. 1985.] it is
known that a significant detrimental negative effect of inbreeding on egg
hatching was not observed in not only one-time but also three-, four-time
crossbreeding of close relatives.
In our experience, the hatching of inbred systems is slightly different
than that of controls. For example, the hatching of the F-1 and F-2 systems
Systems
Years
Average number of
normal eggs, pieces
The average weight
of the stock, mg
The average weight of
an egg, mg
Physiologically
unfit %
Hatching of eggs,
%
X
±S
x
Сv,%
X
±S
x
Сv,%
X
±S
x
Сv,%
X
±S
x
Сv,%
X
±S
x
Сv,
%
F-1
J
5
2007
497±19,6
18,6
287±10,1
18,6
0,578±0,001
9,6
3,7±0,06
11,4
96,9±4,0*
3,0
J
9
2011
637±17,1
14,8
371±8,1
13,7
0,581±0,002
7,8
5,2±0,4
13,4
95,3±3,5*
3,4
F-2
J
5
2007
527±17,8
21,1
293±8,4
20,4
0,556±0,001
8,3
2,2±0,5
9,3
94,2±4,1
4,8
J
9
2011
646±14,8.
12,3
368±8,3
10,9
0,570±0,005
4,0
3,2±0,2
8,6
97,4±2,0
3,5
System 51
(comparative)
2011
711±8,7
7,8
392±5,9
10,0
0,580±0,003
6,2
2,1±0,1
6,0
96,1±3,0
3,0
F-3
J
5
2007
438±22,4
24,6
258±10,6
23,0
0,589±0,006
6,0
5,6±1,5
9,2
93,3±5,2
4,1
J
9
2011
619±17,1
13,9
361±9,6
15,6
0,587±0,007
6,0
3,2±1,0
7,4
91,9±5,0
4,2
F-4
J
5
2007
458±27,1
19,0
260±10,1
14,7
0,568±0,007
6,3
4,0±0,1
5,5
87,8±5,1
4,0
J
9
2011
620±17,1
11,6
340±8,7
7,5
0,549±0,005
4,2
4,0±0,5
6,8
94,0±4,9
3,5
System 48
(comparative)
2011
663±6,7
6,2
415±5,3
9,6
0,587±0,005
8,4
5,3±0,1
5,6
96,7±3,0
30,
Systems
Inbreeding
generations
Years Viability of
silkworms, %
The weight of a
shell, mg
The weight of a
cocoon, g
Silkiness,%
Х±SÑ
Сv
Х±SÑ
Сv
Х±SÑ
Сv Х±SÑ
Sv
F-1
J
5
2007 66,8±2,8
18,3 384±8,5
9,6
1,05±0,03 6,7 23,4±0,2
3,2
J
9
2011 77,4*±5,8 18,3 432±16,6 9,4
1,84±0,06 7,5 23,6*±0,2
1,7
F-2
J
5
2007 60,9±6,9
43,6 395±8,9
8,7
1,73±0,03 6,4 22,9±0,2
3,4
J
9
2011 77,7±6,1
19,2 394±19,8 12,3 1,72±0,08 7,8 23,2±0,3
3,0
Line-
51(comparative)
81,8±1,9
8,6
515±9,8
7,5
2,05±0,03 5,1 25,1±0,2
3,8
F-3
J
5
2007 54,0±3,9
29,5 377±8,4
9,2
1,72±0,03 7,5 22,1±0,3
1,1
J
9
2011 84,9±3,9
11,2 422±13,3 13,5 1,85±0,06 7,8 22,8±0,7
6,9
F-4
J
5
2007 53,1±3,5
28,2 405±12,4 12,2 1,72±0,04 9,1 23,8±0,03
4,8
J
9
2011 78,3±5,7
17,7 430±4,9
2,8
1,85±0,02 2,2 23,2±0,2
1,6
Line-
48(comparative)
84,7±1,6
8,2
534±10,0 6,9
2,11±0,03 4,8 25,2±0,3
4,0
Scientific research results in pandemic conditions (COVID-19)
27
is 95.3% and 97.4%, while in the L-51 control it is 95.1%. This was done in
an experiment with the S-5 breed, where the highest coefficients of
phenotypic correlation were found between silkworm viability and egg
hatching, cocoon weight, and egg weight in the nest [Nasirillaev U.N. 1985.]
is consistent with the results obtained. Seed viability in systems with such
viability plus selection is as follows: in F-1 - 95.3%, in F-3 - 91.9%, and in
minus-selected systems - F-2 - 97.45 and in F-4 - 94.0%.
An interesting picture is observed on the viability of silkworms, and this
can be seen in Table 4.1.2.
In experiments [Shurshikova NV, Nasriddinova SV 1981.], a decrease in
viability in the first inbred generations of SANIISh-21 and SANIISh-30 was
observed, and in all subsequent generations from the fourth generation on
bred material viability was high and not less than control, but it was even
greater than that of the control.
The viability of the systems studied in our experience is appropriate
with the control.
However, no stabilization of viability has been observed across inbred
generations. This is also evidenced by the high coefficients of variability in
all inbred systems. For example, Sv = 18.3% in F-1, Sv = 19.2% in F-2, and
8.2% in control. This is explained by the fact that the viability of mulberry
silkworms is closely related to external environmental conditions.
[Strunnikov V.A. 1994.] noted that mulberry silkworm breeds are
saturated with a large number of harmful recessive genes, some of which,
especially in kinship reproduction, become homozygous, thus creating a
constant source of variability in quantitative traits. In our experience, this is
indicated by indicators such as shell weight, cocoon weight, and silkiness.
There is no difference in performance in systems with plus and minus
selection. In the F-1 and F-3 systems, which were selected for viability plus,
the cocoon weight values were 1.84 g and 1.85 g, and the shell weights were
432 mg and 422 mg, respectively. In practice, the minus selection does not
differ from those of the conducted F-2 and F-4 systems - 1.72 g and 1.85 g,
respectively; 394 mg and 420 mg. Clearly, the choice of viability leads to the
accumulation of recessive hemispheric and subletal genes in the
homozygous state in the system. As a result, some organisms die at different
stages of development. But some of them survive. Probably on the one hand,
because harmful genes are less accumulated, and on the other hand, because
there are enough positive genes to compensate for the effects of harmful
genes, i.e., CCG is formed.
Had this process not taken place, no doubt the system would have
perished as a result of negative selection over several generations. It follows
that CCG does not occur in systems with high viability. The predominance of
positive genes over negative genes is achieved without them. In addition, the
Scientific research results in pandemic conditions (COVID-19)
28
process of mutation is accelerated under the influence of negative selection.
This increases gene diversity.
Thus, not only the reserve but also the newly emerging genes remain
the source for the blocks of both categories.
Reference:
1. ÐаÑÑиддинова С. ÐизнеÑпоÑобноÑÑÑ ÑелкопÑÑда и маÑÑа кокона
пÑи инбÑедном Ñазведении меÑенной по Ð¿Ð¾Ð»Ñ Ð¸ немеÑеной поÑодÑ.
//Ð Ñб. «ÐоÑÑÐ¸Ð¶ÐµÐ½Ð¸Ñ Ð³ÐµÐ½ÐµÑики и ÑелекÑии ÑÑÑового ÑелкопÑÑда и
ÑелковиÑÑ. -ТаÑкенÑ. Ð. 6, 1978. âС.103-119.
2. ÐаÑÑиддинова С., ШÑÑÑикова Ð.Ð. Ðзменение геÑеÑозиÑа под
влиÑнием оÑбоÑа пÑи инбÑедном Ñазведении ÑÑÑового ÑелкопÑÑда.
//Ð Ñб. «ÐаÑÑнÑе оÑÐ½Ð¾Ð²Ñ ÑазвиÑÐ¸Ñ ÑелководÑÑва». //Ð.13, -ТаÑкенÑ,
1979. âС.49-54.
3.
ÐаÑÑиддинова
С.Ð.,
СÑÑÑнников
Ð.Ð.
СÑановление
комбинаÑионной ÑпоÑобноÑÑи Ñ Ð¸Ð½Ð±ÑеднÑÑ
линий ÑÑÑового
ÑелкопÑÑда. -1991, -Т.318. -â3.-С.736-740.
4. СÑÑÑнников Ð.Ð. ÐенеÑиÑеÑкие меÑÐ¾Ð´Ñ ÑелекÑии и ÑегÑлÑÑии
пола ÑÑÑового ÑелкопÑÑда. //Ð., ÐгÑопÑомиздаÑ, 1987 г.-С.12-154.
5. СÑÑÑнников Ð.Ð. ÐÑиÑода геÑеÑозиÑа и новÑе меÑÐ¾Ð´Ñ ÐµÐ³Ð¾
повÑÑениÑ, //ÐоÑква, «ÐаÑка», 1994 г.-С.3-103.
6. ÐаÑиÑиллаев У.Ð. ÐенеÑиÑеÑкие оÑÐ½Ð¾Ð²Ñ Ð¾ÑбоÑа ÑÑÑового
ÑелкопÑÑда. //Ðзд-во «Фан», - ТаÑкенÑ, 1985.-С.3-50.
7.Daniyarov U.T. Abstract of Doctorate dissertation 2019.
Nargiza Dusmukhamedova Independent researcher of the Academy of
Public Administration under the President of the Republic of Uzbekistan
SOME ASPECTS OF ENSURING THE RIGHTS OF CHILDREN TO EDUCATION
IN CASE OF A PANDEMIC
N. Dusmukhamedova
Abstract: The article discusses some topical issues of ensuring the right
of children to education in a pandemic. The transition to a distance and
online system of continuing general secondary, secondary special and
higher education in Uzbekistan, the positive and problematic aspects of this
system, the results of studying the experience of international organizations
and foreign countries in this field are discussed.
Key words: the right to education, the impact of the pandemic on the
education system, online education, distance learning, UNICEF initiatives, a