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	You must Log In to use the Crop Development Tool. A cotton plant, when not stressed, grows in a predictable way, which allows its crop development to be predicted using daily temperature data (day degrees).  The Crop Development Tool (CDT) allows crop managers to monitor both vegetative and reproductive growth of their crops compared to potential rates of development. The CDT allows analysis of: Squaring Nodes Nodes Above White Flower (NAWF) Square Numbers Boll Numbers Vegetative Growth Rate
	Fruit Development Graph Information
	Tracking fruiting nodes is one means to assess crop progress. Ultimately it is important however to ensure that this crop growth is translated into fruit production (square and bolls) that will help attain profitable yield.  The fruit development graph displays number of observed squares or bolls per meter plotted against a potential rate of fruit development based on day degree accumulation after sowing. The potential square development commences at 500 DD (time of first square) and estimates the number of squares required to meet a potential rate of development based on node development rate of 42dd per node and a standard plant population.  Similarly the potential boll development commences at 750 DD (time of first flower) after sowing and the rate of boll development is similar to the rate of square development, although it assumes that there are some losses of fruit associated with carbon stress or normal crop growth (not pest, nutritional or water stress).  This is the reason that the slope of the boll development curve is not parallel to the square curve and the slope is less. Differences in measurements between the square and boll curve can be an indication of overall fruit retention. The time to cease maintaining a crop at potential boll development will be dependant on the time of last effective flower which can vary from season to season.  To assist this decision you may like to consider using the Last Effective Flower Tool.
	Vegetative Growth Rate Information
	Plant growth regulators (PGRs) such as Mepiquat Chloride (PIX) provide cotton growers with a method to help avoid excessive vegetative growth.  Such growth is a problem because it may reduce retention of fruit caused by self-shading and thus can delay harvest. Reduced efficiency of insecticides due to poor penetration of the canopy is also a problem. Monitoring the growth rate of a crop can help to identify whether excessive growth is occurring. One technique used to monitor growth is Vegetative Growth Rate, which is the rate of change of plant height relative to the rate of node development:
	Measurements should be started as the crop approaches first flower, i.e. 12 mainstream nodes.   The monitoring should continue from the first half of the flowering stage as rapid increases in growth rate can occur at anytime in this period.  Less tipping out in Bollgard® II crops does make it easier to monitor than conventional cotton. To monitor VGR follow these steps; Measure plant height (in cm) from the ground to the growing point of the main stem (not to the end of the top leaf) Count the number of nodes from the cotyledons (numbered 0) to the top node that has a fully unfurled leaf. Measure the plant height and count the total number of nodes on at least 20 randomly chosen plants. Carry out the same procedure one-week later and then use the VGR formula to calculate the rate of internode increase, measured in centimetres per node.  The CDT tool does this calculation for you. Late Pix Applications:  VGR measurements are specifically designed to provide information to assist with growth regulator use during rapid vegetative growth.  It is common practice to alternately, or also, apply growth regulators at cutout (when flowering and fruit set has stopped).  This application timing is designed to suppress unnecessary vegetative growth during boll ripening and can ensure more even crop maturity. Decisions on cutout application of growth regulators are based on factors such as: Attainment of target boll numbers; Resumption of unnecessary late vegetative growth or fruiting; Reaching Last Effective Flower date for the region. Row Spacing:  Note these VGR associations with possible growth regulator use have been developed for 100cm row cropping systems.  With UNR or 38cm row spacings, VGR and plant growth are suppressed, so alternative calibrations may be required.
	Node Development Graph Information
	Monitoring aspects of fruiting dynamics is useful to determine whether crop development has been up to potential and may enable identification of sluggish crops which need to be pushed.  It is important to make such a diagnosis early otherwise crop setback and delay may impact on yield and maturity. The Day Degrees and Node Counts are graphed and displayed against a theoretical optimum crop development rate to determine where the crop development is at this time.  Measurements well above the line can indicate the need for growth regulators.  Measurements well below the line indicate a problem with the crop development that may require a management solution (ie: water, fertiliser, etc). All Observation Dates must be after the Sowing Date or they should be left blank. Future Observation Dates are ignored. An Observation Date of today will use cumulative Day Degrees up until yesterday.   All Node Counts must be greater than 0 or they should be left blank.