Emergence to First Stage 1 - Texas A&M Universityccag.tamu.edu/files/2017/05/Phase-Iv1.pdf · 2017. 5. 23. · 5-10 days 25 - 35 days 5 – 6 days / node Phenological Stages Phase

Emergence to First SquareStage 1

Stand Establishment Period

Juan A. LandivarDirector of Research

Texas AgriLife Research and Extension CenterCorpus Christi, Texas

Improving Life through Science and Technology.

30 days

35 days

Phase I Phase II

Phase III Phase IV

30 to 40 days after Cutout

Germination

First Square(6 nodes)

Planting

5-10 days 25 - 35 days 5 – 6days / node

Phenological StagesPhase I

Days from germination to first square

0

10

20

30

40

50

60

70

15 20 25 30 35 40Temperature (C)

Day

s

GerminationMarch 15

Harvest Aug. 15

150 Days

30

FSQ

April 15

Production window

Effect of emergence time to stand establishment and final lint yield

Germination (days after planting)

% Survival

Relative yield (%)

5 87 100

8 70 4612 30 29

Source: Wanjura, 1969

Yield vs. plant density

1000

2000

3000

4000

4 6 8 10 12 14 16 18

Plant / m

Kgs

/ H

a.

Relative yield vs. density

8084889296

100104

4 6 8 10 12 14 16 18Plants / m

% d

e M

ax.

Suggested plant density

6 to 8 plants/m or 2 to 3 plants per 

Avoid 10 or more plant/m (more than 3.5 plants per ft)

Use of seed treatment is highly recommended to protect the plants

against early season insects(Aphids, thrips)

Aphid and thrips damage

Phase IIPhase I

27 days

Chemical weed control is criticalat this stage

Time course of root development

FSQ FBL

Relative root and boll growth

0

20

40

60

80

100

120

0 5 10 15 20 25 30 35

% o

f Max

. .

Number of Nodes

Roots Bolls

Fist Bloom

% reduction in yield caused by delays in timimg of weed control 

0102030405060708090

100

0 (*) 1 2 3 4Weeks of delay

(*) 20 days after emergence

Height at first bloom 

0

10

20

30

40

50

60

70

Manual Residual RR SystemMethod of weed control

Nematode Infestation

• What can we do ?– Crop rotation– Avoid traffic of equipment and personnel

from infested fields– Use chemical control

Final Objective of Phase I