ACADEMIC RESEARCH IN MODERN SCIENCE
International scientific-online conference
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GROWTH MONITORING
Ergashev Dilshodbek Shuxratjon o`g`li
Andijan Institute of Agriculture and Agrotechnologies
Master degree student
+99894 560-37-00
https://doi.org/10.5281/zenodo.13903688
Annotation
Cotton plant is an excellent teacher, if you can translate its language”. When
agronomists and farmers can learn this “language”, they get the most valuable
tool, a very useful input, to obtain a sustainable and more efficient production,
and specially, more predictable. Cotton management concept involves different
aspects such as weed and insect control, plant growth monitoring, use of PGR’s
and harvest aids. In this circumstance focus will be directed to the measuring
techniques required for the success of the crop according its growth stages. In
this paper, the most relevant or easiest indexes will be mentioned, only for time
and space reasons, we exclude other existing, also important
Key words:
Cotton, Growth rate, NAWF, nodes, flower.
Growth rate:
Another useful index to weigh crop evolution is Growth Rate.
When field data, considering height and node number, is picked in a regular base
(7 to 10 days intervals), the change in the figures between subsequent
evaluations give a valuable instant information about the growth rhythm.To
know this we have to calculate the differences between present and previous
values of height, and in the same way with the node numbers, then we work out
the rate between height and node number differences. The result is a figure that
represents the average length of newly made nodes. This value must be graphed
in the Y-axis of the reference curve, referred to the exact middle point between
both nodes monitored (present and previous) in the X-axis. It is desirable that
the real value obtained is equal or very close to optimal situation.
The growth rate declines after flowering, due to various factors, like boll
setting, and loading, diseases, fertility, irrigation, management, pests. But we
have to consider this is also a natural plant process to give way to yield
definition, despite all those factors. At this moment, HN R and GR cease to be
sensitive indexes to monitor crop progress.
ACADEMIC RESEARCH IN MODERN SCIENCE
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Nodes Above White Flower (NAWF):
During vegetative growth, cotton
plant can develop a new node each 40-50 day degrees; when fruiting positions
start to compete with stems for carbohydrates the node production rate
decreases. This begins at about node fifteenth. At this moment squares turn into
flowers at a regular rate, generally, a 3 day interval between first position
flowers of successive branches can be expected.To determine NAWF, we
consider the node associated with first position open flower in the first fruiting
branch as node 0 and count successive nodes to the top, considering the last to
be counted the one associated with a leaf of at least 2,5 cm of diameter.In this
stage the fruiting development increases the carbohydrates demand over the
vegetative growth; the NAWF gives the difference between each new node rate
and an idea of the movement of the first position flower through the main stem.
The NAWF values obtained when the first blooms appear or even when first
position flower gets close to the top are still good indexes to estimate the
balance between vegetative growth and development. The first flower in non
stressed crop is commonly associated with 8 to 9 NAWF. If the value is less than
8 there are evidences of limiting circumstances, most times related with water
status, soil compaction layers, salt , diseases or nematodes. In optimum
environments the NAWF initial value decreases normally at a rate of one node
each 8.3 days. The crop cut-out occurs at about 5 nodes above the white flower.
It is suggested that insect protection must extend until two weeks after crop
reaches 4 nodes above white flower, at least. With 5 nodes above the white
flower, 95% of all harvestable first position bolls are considered to be at flower
stage. The common crop practices that can affect this index, we can mention
Growth Rate
0
1
2
3
4
5
6
7
8
9
10
11
4
6
8
10
12
14
16
18
20
22
nodes
ACADEMIC RESEARCH IN MODERN SCIENCE
International scientific-online conference
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early boll setting, irrigation schedule (or water availability), nitrogen rates, and
PGR use.
CONCLUSIONS
In a few words, to weigh the value of Crop Growth Monitoring and its
indexes in cotton production, we can affirm that its use and validation
makes it possible to:
•
Interpret each of one of the phenologycal crop phases and
their momentarily demands.
•
Project crop growth trends and be able to predict them.
•
Fine-tune the field operations management and timing.
•
Minimize random factors to the least in the production (more
predictability)
Increase sustainability of the whole production system
References:
1.
Constable, G. A. (1992). Managing cotton growth. 1992 Australian Cotton
Conference Proceedings. August 12 – 14, 1992.
2.
Deltapine, (1998). Deltapine Seed, Cotton Management Guide. 64 pag.
3.
Hake S. Johnson, Kerby T. A. And Hake K. D. (1993). Cotton Production
Manual.
4.
University of California. Division of Agriculture and Natural Resources.
Publication 3352, 417 pag.
5.
Mauney, J. R. (1986). Vegetative growth and development of fruiting sites.
In J.R. Mauney and J. Mc D. Stewart. Cotton Physiology. The Cotton Foundation,
Memphis, Tennessee.
Nodes Above Withe Flower
0
1
2
3
4
5
6
7
8
9
10
11
0
5
10
15
20
25
30
35
40
45
50
55
Days after 1st flower
