Assessment of morphological attributes of Guava tree for design of a novel tunnel spraying system

The morphological attributes play a significant role in determining the level of applied insecticide by the existing spraying system. Therefore, this attempt was made to assess the various morphological attributes of guava tree such as leaf size, leaf area, leaf area index (LAI) and leaf area density (LAD). In this study, two leaf area estimation techniques (grid count method and Image processing technique based on ImageJ software) were compared and also estimate LAI and LAD for ten trees. An average leaf area was registered 29.56 cm2 and R2 value (0.98) for predicting leaf area by image processing technique. The LAI and LAD varied from 0.69 to 2.17 m2/m2 and 0.53 to 1.89 m2/m3, respectively. In addition, minimum and maximum LAD (mean ± SD) for zone wise ranged from 0.07 ± 0.06 m2/m3 to 2.73 ± 1.43 m2/m3, respectively. The study findings provide an opportunity to deal with large volume of leafs for leaf area estimation and would also help in design of various sprayers like determining the dimensions of tunnel sprayer and allow them to test in laboratory conditions with simulated artificial tree.