Determination of irrigation time of zucchini using leaf color in LAB color system and evaluation by C5 tree model

Considering Iran's climate condition, which is one of the arid and semi-arid countries of the world, irrigation planning is a type of management operation to properly determine irrigation time. One of the fastest and most accurate methods to determine the irrigation time is to use plant index.This study aimed to investigate the relationship between leaf color and soil moisture deficiency by LAB color system to determine irrigation time and modeling of water stresses by C5 tree model in zucchini plants with20 irrigation treatments f 100% to 15% with 5% spacing and two non-irrigated treatments ( Control) and over-irrigation (120%).Weight and moisture content of leaves were measured daily for 20 consecutive days and finally results showed that with decreasing moisture, L(Lightness) and B(Blue- yellow) parameters decreased and A(Green-red) increased.Irrigation time was also determined for pumpkin plant, fifth day at L = 68, A = -19 and B = 37.3. On the other hand, using the C5 tree model to predict soil moisture stresses under two scenarios (taking into account the day and not taking into account the day) showed that this model was more accurate with respect to the days of stress application with a value of 95/85. Percentage. Therefore, leaf surface color in LAB color system can be used to determine irrigation time and to determine the amount of stress.