CropPest DSS
Population Trend Index

Data on the survival rate of different life stages of an insect, sex ratio (proportion of females), and adult fecundity generated at different temperatures can be used to construct a life table. To set the initial standard number of the counter, observed data on life stages (preferably adult or egg stages) are provided as inputs along with prevailing temperatures at the location. Population trend index (I), is indicative of the population growth rate in the next generation over the initial number. The output gives the potential population projection without taking into account the natural mortality at the start of the next generation.