Pests and diseases monitoring in forests and rangelands of Turani, Iran zone in Kerman province

Failure to pay attention to the protection of water resources, soil and plant resources has caused the destruction of these resources. Among the effective factors in this destruction, we can point out land use conversion without a comprehensive approach, cutting down forests, destroying rangeland, drought, damage by pests and diseases. Pests and plant diseases in the forests and rangelands of the country are considered one of the most important factors of forest destruction. For the prevention and management of the outbreak of pests and plant diseases, there is a need for monitoring and a comprehensive management plan for pests and plant diseases. As the largest province in the country, Kerman province is part of the Turani, Iran zone, and out of the total area of 181737 square kilometers of this province, about 5% of agricultural land, 45% of rangeland, 13% of forest and 37% of desert.

To evaluate and monitor the status of the most important pests and pathogens of the main plants and considering the diversity of environmental conditions and the area of forests and natural rangeland in Kerman province, sampling was carried out during the years 2018 to 2020. The monitoring plan was implemented in Dehno, Babzangi, Kohpanj and Glochar stations as well as Yazdanabad and Raviz areas as two mountain almond tree habitats. The most important forest communities (trees-shrubs) and rangeland in the mentioned areas are Juniperus excelsa M.Bieb. , Amygdalus scoparia Spach. , Amygdalus elaeagnifolia Spach., Artemisia aucheri Boiss's, Artemisia siberi Besser, Stipa arabica Trin. & Rupr and Zygophyllum atriplicoides Fisch. & C. A. Mey. Periodic sampling of pests and pathogens was done in those plants in the desired parts. In sampling, the type and level of contamination with pests and pathogens were recorded. Due to the thinness of the almond forests in the investigated areas in Kerman province, the transect sampling method was used in the form of continuous lines. Data collection from rangeland areas was done during field visits of representative plant types. Sampling in this range was based on systematic random method.  

Based on the investigations carried out at the Dehno Bardsir station as the habitat of Z. atriplicoides, the seed-eating moth from the Lepidoptera order, at the Dehno Bardsir and kohpanj Bardsir stations as the habitat of S. arabica, the Tranzscheliella iranica S. and Dehno Bardsir and Kohpanj Bardsir stations as habitats of A. aucheri and A. siberi, Gallfly from the family of Cecidomyiidae was isolated and identified with about 4% contamination, also from Yazdanabad Zarand region as a habitat of A. scoparia, wood-borer beetle capnodis tenebrionis with about 30% contamination and from Raviz area of Rafsanjan as a habitat of A. elaeagnifolia, mistletoe Loranthus grewinkii Boiss. & Buhse was detected with about 60% contamination. The population fluctuations of the pests of seed-eating moth, gallfly and wood-borer beetle in mountain almonds and the the stipa smut pathogen in the years of monitoring of damaging agents in the studied areas was almost constant and no particular fluctuation was observed in these agents population. However, the population of mistletoe as a semi-parasitic plant based on A. elaeagnifolia decreased in the studied area in 2019 and again in 2020, it was returned to the level of the previous years. The reason for the decrease in the population of L. grewinkii in 2019 was the pruning of the infested tree branches to the mistletoe plant.

Due to the unprincipled pruning, this semi-parasitic plant grew again from the previous contaminated places and reached the previous population level in the following year, according to the results of the seed-eating moth pests. The dormant Gallfly, and the stipa smut have a low population, and based on their population fluctuations in the studied years, they were in equilibrium with the host plants in their natural environment and do not have an overflowing state. Based on the results, the populations of C. tenebrionis and L. grewinkii are high in the host plants, causing severe damage and reducing the growth and reproduction of the host. It is necessary to continue detection pests and diseases in different regions in order to monitor the existing factors and the newfound factors to prevent their entry and spread.