Image Analysis Estimate of Leaf Area Damage Caused by Citrus Leafminer, Phyllocnistis citrella (Lepidoptera: Gracillariidae) Larvae on Different Citrus Cultivars.

Citrus leafminer (CLM), Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) is among the serious insect pests attacking citrus plants in Pakistan. The study was conducted to quantify the leaf area damage of eight citrus cultivars caused by mining activity of CLM during summer 2016. The total leaf area and mine area per leaf were calculated by the image analysis method using Sigma Scan Pro 5.0 software. The results of the present study showed that CLM generated larger mines; 1.64 cm2 on Grapefruit, 1.44 cm2 on Kinnow and 1.40 cm2 on Succari compared to other five cultivars. However, the percent leaf damage due to the feeding of CLM larvae was observed higher 44.2% on Fairchild, 36.5% on seedless Kinnow, 36.3% on Feutrell's early and 35.8% on Kinnow that showed great susceptibility to CLM. Smallest mines generated by CLM larvae were found on China Lemon and Succari showing the lowest damage percentage compared to other cultivars. Conclusively, the C. tangerines and C. mandarins were the most preferred cultivars by CLM larvae for feeding on the leaf surface. The image analysis method was accurate, relatively simple, easy and inexpensive to calculate the leaf area damage caused by CLM larvae. [ABSTRACT FROM AUTHOR]