HTU Calculator

The index helio thermal unit (HTU) serves to be effective in taking into account and expressing the effect of varying ambient temperature on the duration between the phenological events for comparing the crop response to the ambient temperature between phenological stages. Helio thermal unit is calculated using the formula

HTU = ∑ GDD x Cumulative Sun Shine Hours (from sowing to physiological maturity)

Helio-thermal unit of a definite phenology is the product of the length of sunshine hour of a day and required days of the phenology accumulated heat unit by plants. The interaction effect of sowing times and cultivars on helio-thermal unit (HTU) was significant for all the phenological stages of plant growth upto Maturity. At normal growing condition, heat tolerant cultivars requires highest HTU, whereas heat sensitive cultivar requires the lowest HTU for attaining different phenological stages.

Start Date
End Date
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Enter GDD Base Temperature: °C ( We will type the integer value of max 2 digits only)
         
(Example:  Pl.  Enter 20 o F and calculate & see the graph  and data  displayed,  we need same way in o C)
         
CALCULATE   REMOVE  ANATONE STATION
     
  Anatone 2014 accumulated HTU: xxxxxx
GRAPH       Date  vs  HTU    

   

Jan 01-Jan 16

Year

HTU  when base temp=20°F

 

2014

24000

Current (graphed by default)

2013

8200

Minimum (graphed by default)

2012

18900

Show 2012 on graph

2011

13700

Show 2011 on graph

2010

30500

Maximum (graphed by default)

Average

19100