نوع مقاله : علمی پژوهشی-فارسی
نویسندگان
1 گروه گیاهپزشکی، دانشکده کشاورزی، دانشگاه ولی عصرعج رفسنجان، رفسنجان، ایران
2 گروه ژنتیک و تولیدات گیاهی، دانشکده کشاورزی، دانشگاه ولی عصرعج رفسنجان، رفسنجان، ایران
3 گروه علوم باغبانی، دانشکده کشاورزی، دانشگاه ولی عصرعج رفسنجان، رفسنجان، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objective
Root-knot nematodes (Meloidogyne spp.) are serious pathogens in pistachio orchards and nurseries. Unfortunately, in most orchards, regular monitoring and correct use of integrated nematode management methods are not done. Nematode damage, along with the salinity and alkalinity of the soil in most pistachio orchards and unprincipled fertilization, has caused a significant decrease in pistachio production per hectare. Chemical nematicides for control lead to environmental pollution and seriously threaten human health. Therefore, finding low-risk methods to manage root-knot nematodes is a priority. Soil and bio solarization, soil amendments using organic fertilizers such as cow, poultry manure, and agricultural fermentation waste have shown convincing results. Following the observation of different levels of nematode control using mineral and chemical fertilizers, the present study was designed. So, the effect of different sulfur concentrations and application time on the control of root-knot nematode, Meloidogyne javanica, and its effect on growth factors of pistachio plants was surveyed.
Materials and Methods
The experimental treatments were different sulfur concentrations (zero, 50, 100, and 150 mg/kg of soil) and two application methods of sulfur (first time, simultaneous planting of pistachio seedlings with sulfur and nematode treatments and second time, planting of pistachio seedlings after 45 days of sulfur application and nematode inoculation) in four pistachio cultivars (Akbari, Qazvini, Badami Reez Zarand and Sefid Pistachio Nogh). The pure population of root-knot nematode was propagated on Solanum lycopersicum L. cv. Standard. The number of two second-stage juveniles was considered for inoculating each gram of soil. The pathogenicity indexes of nematode, including the number of second-stage juveniles per 300 grams of soil, the number of galls, and egg masses per gram of root, were calculated after two months of planting. Growth factors, including green leaf weight, fresh and dry weight of root and stem, root volume, stem and root length, stem diameter, and SPAD index, were also measured in all experimental treatments. The experiment was carried out in a factorial, completely randomized design with 12 replicates. SAS software version 9 was used for data analysis. Means were compared using Duncan's test.
Results
A low population of second-stage juveniles was observed in all cultivars at 50 mg/kg sulfur concentration. A significant decrease in gall and egg mass indexes were observed at the second time compared to the first sulfur application. Except for the Akbari cultivar, the nematode reproduction factor showed a significant reduction at 50 mg/kg. In the absence of nematodes in the Akbari cultivar, the concentration of 150 mg/kg of sulfur increased the stem fresh weight by 40% compared to the control. Regardless of the concentration, the first time showed better results on the SPAD in three Akbari, Qazvini, and Badami cultivars. In the presence of nematode and the second time, the concentration of 50 mg/kg of sulfur for the Qazvini cultivar caused a 68% increase in the stem fresh weight, 32% in the stem length, and 22% in the stem diameter and the same conditions, for Qazvini and Sefid Pistachio Nogh, had the greatest effect on the leaf weight. The concentration of 50 mg/kg of sulfur and the second time for Qazvini and Sefid pistachio Nogh cultivars had the highest effect on the green leaf weight compared to the control in the presence of nematodes.
Discussion
In this research, apart from the Akbari cultivar, the largest decrease was observed in the soil covered with plastic in three other cultivars. According to the results of this research, using a concentration of 50 mg/kg of sulfur, covering the soil surface, and planting pistachio seeds after 45 days can significantly reduce the root-knot nematode population. This finding can be used in pistachio nurseries. For further studies, it is suggested to use sulfur fertilizers and their mixture with biological agents compatible with salty and alkaline soils of pistachio planting areas to reduce the population of root-knot nematodes.
کلیدواژه‌ها [English]
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