Evaluation of Relative Resistance of some Pistacia Rootstocks to Gummosis Disease

Document Type : Original Article

Authors

1 Department of plant genetics and production engineering, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.

2 Department of plant genetics and production engineering, Faculty of agriculture and natural resources, University of Mohaghegh Ardabili, Ardabil, Iran.

3 Department of Genetics and Plant Production, Faculty of Agriculture, Valiasr University, Rafsanjan, Rafsanjan, Iran.

4 Department of Plant Protection, Faculty of Agriculture, Valiasr University, Rafsanjan, Rafsanjan, Iran

5 Pistachio Research Center

Abstract

Abstract:
Gummosis (Phytophthora Crown and Root Rot) is one of the Most Important Diseases of Pistachio Trees. In Order to Evaluate the Relative Resistance of 29 Rootstocks of Pistacia to this Disease, a Factorial Experiment was Conducted with Two Factors Rootstocks Type and Disease Stress, Based on Completely Randomized Design with Three Replications. Two-Month-old Pistachio Seedlings were Artificially Inoculated with Phytophthora Drechsleri and After Six Months, Evaluation Was Done. The Resistance of Rootstocks was Evaluated by Determining the Percent of Crown Rot Girdling, Disease Severity and Mortality Indices and Measuring the Stem Length, Stem and Root Dry Weight Traits in Control and Stress levels. The Results Showed that There was a Significant Difference Between the Studied Rootstocks in Terms of Resistance to Disease. The Disease Stress Caused a Decrease in Stem Length, Stem and Root Dry Weight of Seedlings. The Atlantica Had the lowest Amount of Crown Girdling (20%) and Disease Severity (17%) and in Terms of Disease Severity, it Showed a Significant Difference with other Rootstocks. The Sarakhs Rootstock Had also the Highest Amount of Crown Girdling (95%), Disease Severity (90%) and Mortality (55.55%) and in Terms of These Indices, it was Significantly Different from other Rootstocks. Therefore, Atlantica was the most Resistant and Sarakhs the most Susceptible Pistacia Rootstocks Against Gummosis Disease. The Cluster Analysis Divided the Rootstocks into Four Groups: Resistant (Atlantica, Integerrima and UCB1), Moderately Resistant (Mutika, Benebaghi, Kalleghouchi, Ghazvini, Gholamrezaei, Italiaei, Ahmad Aghaei, M5 and BK1), and Moderately Susceptible and Susceptible .

Keywords

Main Subjects