Page 26 - 17 Cotton SA March 2019

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stages, it is important to record the uppermost In Australia, a value of 8 is used to express
white flower in the plant. This flower is used the NAWF value and plants should be monitored
to determine cotton cut-out, or “nodes above when approximately half the plants have a pink
white flower” (NAWF) (see Figure 5) (Ritchie & or white flower on a fruiting branch. Count
Bednarz, 2007; www.faststartcotton.com.au). the number of nodes above the highest first
position flower, including the node nearest
the terminal with an associated unfurled leaf
(www.fast startcotton.com.au). A high number
Figure 5: Plant structure showing upper first position (>7) indicates that the plant is growing
white flower.
vigorously, and the use of a growth regulator
Highest node with unfolded should be considered.
main stem The occurrence of pests can be noted against
the plant stages. Knowing the planting date,
Terminal growth one can calculate when your cotton will reach a
6 specific development stage (see Figure 6).
5
4 For references, please contact the author.
Nodes above
3 white flower = 6
2
Squares
1
Pink flower
(pollinated)
2 3
1
Upper first-position Fruiting positions Bt-cotton
white flower
should also be
scouted to make sure
the cotton plants are
resistant to bollworm.
Report any problems
to the licence
holder. ”
Sympodial (fruiting) branches

Second Third
First position boll position boll
Vegetative branch position boll

Main stem
Main stem nodes

Cotyledonary node

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