The Effects of Arbuscular Mycorrhizal Fungi and Lead (Pb)Applications on Eggplant Seedling Growth and Nutrient Uptake

Bitkilerin gelisimini olumsuz etkileyen bircok faktor vardir. Bu faktorlerden biri de fide doneminde bitkiye toksik etkiye sebep olan kursun (Pb)’dur. Mikorizalar ise bitki gelisimine olumlu yonde katki saglamaktadir. Patlican fidesinde, mikorizanin kursunun olumsuz etkisinin tolere edip etmeyecegi arastirilmistir. Bu calismada, Gigaspora margarita ve Glomus intraradices mikoriza irklari tohum ekiminden once uygulanmistir. Ilk gercek yaprak gorundukten sonra kursunun 5 farkli dozu (0, 100, 200, 400 ve 800 ppm) verilmistir. Sonuc olarak gercek yaprak gorunme suresi, en genis kotiledon ve en uzun kotiledon Gigaspora margarita uygulamasindan alinmistir. Diger fide gelisim parametreleri bakimindan, en yuksek degerler Gigaspora margarita-0 ppm Pb uygulamasindan elde edilmistir. Ayrica kontrolde 0 ve 100 ppm Pb uygulamalarinda yuksek deger aldiklari gorulmustur. Beklenildigi gibi kursunun toksik etkisi sebebiyle Kontrol-800 ppm Pb uygulamasindan bitki elde edilememistir. Fakat her iki mikoriza turunun 800 ppm’lik uygulamalarinda kursunun toksik etkisini tolere ederek gelisimine devam ettikleri gorulmustur. Inceledigimiz diger kriterler, N, P, K ve Ca gibi onemli besin elementlerin yuksek dozda kursun sartlarinda bile mikorizalar araciligiyla bitkiye alinmasidir. Kursununda, mikorizalar tarafindan bitkiye alindigi gorulmustur. Kokteki Pb icerigi, surgundeki Pb iceriginden daha fazladir. Genel olarak fide gelisimi ve besin elementleri icerikleri olumlu etki Gi uygulamasinda elde edildigi gorulmustur.


Introduction
Factors such as a rapidly growth in the population, nutritional deficiencies, irregular urbanization, people's desire for excessive consumption, and developing technology cause the environmental pollution problem (Sağlam and Cihangir, 1995). As in many areas, heavy metal pollution is observed in agricultural areas for various reasons. The most important industrial activities that cause the release of heavy metals to the environment are cement production, iron and steel industry, thermal power plants, glass production, garbage and sludge incineration plants. Considering the natural dispersion of heavy metals, it is reported that heavy metal excretion to the biosphere occurs at different process levels of different sectors (Kahvecioğlu et al., 2002). One of the most remarkable elements, especially among heavy metals, is lead (Pb) . According to Aydın (2002), heavy metals have become an environmental problem in terms of human and community health. Lead that enters the plant through plant roots and stomata accumulates in different parts of the plant. In this way, by entering the food chain, it can affect human health indirectly or through respiration (Çavuşoğlu et al., 2009). Lead contamination rates in nature; it is listed as 10% water, 15% air, 20% food and 55% soil (Anonymous, 2010a). Plant species have different capacities in accumulating and transporting heavy metals. There are studies related to subject. It has been reported that, if plants take these heavy metals as essential nutrients, they pose a serious risk to human health. It is not deemed appropriate for the species in the Solanaceae family to be cultivated near industrial areas. The products in the Solanaceae family can take considerable amounts of heavy metals from the soil with their roots, leaves and fruits (Farooq et al., 2008). In a study conducted on plants belonging to the same family, it was reported that the highest Ni and Cu were in tomato, Co and Cd in potato, and Pb, Zn and Mn in eggplant (Shilev and Babrikov, 2005). Plants grown in soils with high lead content become pale and small-leaved (Sesli, 2003). It causes a reduction in the intake of essential nutrients in the roots and immobilization in the roots. Therefore, significant nutrient deficiency appears on the stem. According to Uysal and Taner (2007), heavy metals negatively affect plants during their growth and development periods. In addition, its effects are more important in germination and seedling stages. Because at this stage, the reactions of plants to stress or toxic factors may be more pronounced (Akıncı and Çalışkan, 2010). In the researches, it was determined that the amount of lead in the root is more than the amount of lead in the leaf. It was reported that this difference between them showed a significant restriction in the transportation of metals from roots to shoots and green leaves (Dahmani et al., 2000). The annual eggplant has an important share among the vegetables produced. Studies on lead toxicity are limited. Plants are fertilized from soil with macro and micronutrients. Using the elements found in the soil is a more realistic approach in terms of both environmental health and natural resources. Mycorrhizal fungi contribute significantly to plant development by supplying water (George et al., 1992). Arbuscular mycorrhizal fungus (AMF) contributes to plants' slow uptake of nutrients from the soil, especially phosphorus. It has been found that mycorrhizal intake nutrients such as phosphorus, zinc and copper when they interact effectively with the plant (Ortaş, 1998). Besides, arbuscular mycorrhizal fungus improves uptake of immobilized plant nutrition, especially phosphorus (Goltapeh et al., 2008;Sawers et al., 2008;Eke et al., 2016;Erdinç et al., 2017). In addition, mycorrhizal has undertaken a protective function against the stress factors and pathogens of the plant with the changes in plant physiology. AMF hyphae contribute to soil conservation by entering the areas that the roots cannot penetrate and improving the soil structure in this way (Dodd and Haas, 1983;Ortaş et al., 2000). There are some studies on this subject. In a study where 0, 75, 150 and 300 mg / l lead doses were applied to tomato seedlings, it caused an increase in lead concentration in leaves, shoots and roots. The content of lead in the tissues of seedlings in low-dose lead application has increased. These values were 312 mg/kg at the roots, 130 mg/kg at the shoot and 510 mg/kg at the roots. In addition, they obtained 917-1750 mg/kg in leaves, 750-1022 mg/kg in exile and 1438-2520 mg/kg in root in high and medium dose lead applications. With the increase of lead, nutrient deficiency has emerged by causing a decrease in the presence of elements such as Ca, Mg, K, P, Na, Fe, Zn, Cu and Mn . In another study conducted in Faisalabad of Pakistan, the concentration of lead in the leaves of spinach, lettuce, cauliflower, radish, coriander and cabbage grown around industrial areas is 2.251 mg / kg, 2.411 mg / kg, 1.331 mg / kg, 2.035 mg / kg, 2.652 mg/kg and 1.921 mg/kg respectively (Farooq et al., 2008). Demir (1998), on the other hand, revealed that the compatibility and development parameters of mycorrhizal in tomato, pepper and eggplant plants grown under greenhouse conditions are higher than those without mycorrhizal.
The negative effects of heavy metals that are more effective during germination and seedling period on plants have been seen in researches. For this reason, the research was carried out during the seedling period. In this study, Gigaspora margarita and Glomus intraradices AMF inocula, which are known to have good interaction with eggplant, were studied. The effects of these mycorrhizas on eggplant seedling growth and plant nutrient content in high doses of lead applications were investigated.

Materials and Methods
This study was carried out in the greenhouses of Selcuk University, Faculty of Agriculture, Department of Horticulture. Plant nutrient analysis was done in the Soil Science and Plant Nutrition Department laboratories. Kemer eggplant variety was used as plant material. Glomus intraradices race were observed 165 spores in 10 g soil. Gigaspora margarita race were determined 100 spores in 10 g of soil. The growth medium was used for germinating seeds and growing seedlings consists of 1: 1 peat and perlite. This growth medium was filled into 250 ml pet cups. The Gi and Gm types were applied in the specified amounts. At this stage, real leaf appearing time, hypocotyl length, cotyledon length and cotyledon widths were measured. Then, when the seedlings started to see the first true leaves, lead (Pb) doses were determined and applied (0, 100, 200, 400 and 800 ppm). Lead acetate ((CH 3COO) 2Pb.3H2O) (Pb = 207.34 g) was used as the lead source. 50 ml of lead acetate was given to plants with injector. Applications were given by irrigation times in three stages, 20 to 26 days after sowing. In this process, cultural procedures were carried out to continue the development of seedlings (Vural et al., 2000). Plants fertilized twice with a Hoagland nutrient solution (about 200-250 cc plant -). Study was set up with 3 repetitions according to the random parcels trial pattern. Twenty pots (20 plants) were kept in each repeat. Seedling transplanting stage, shoot diameter, shoot fresh weight, shoot dry weight, leaf number, root fresh weight, root dry weight, contents of N, P, K, Ca, and Pb elements in shoot and root were examined. At this stage after the plant samples were dried in the oven at 65 °C for 48 hours, was ground with a robot. Grinded shoots and roots are weighed in sensitive scales, weighed 0.2 g, and placed in linear tubes. 5 ml nitric acid and 2 ml hydrogen peroxide were added to them and the tubes were tightly closed. The tubes were then left in the microwave (MARSXpress device) for 15 minutes. The tubes coming out of the microwave oven were opened under the fume hood and placed in falcon tubes. Then 20 ml of distilled water was added. The samples were poured on filter papers and filtered. The filtered samples were read N, P, K, Ca and Pb on the ICP-AES device (Lindsay and Norwell, 1978). Determination of nitrogen was determined by Kjeldahl (6.25 x N) method (Bayraklı, 1987).
In order to determine the effect of the values obtained because of the study according to the application topics, the JMP statistical analysis package program was subjected to variance analysis (Howell, 1987). Trial subjects that were statistically significant in F control were grouped with 5% LSD test.

Results and Discussion
The data that we obtained from all parameters were subjected to variance analysis. The results, which were found significant, were compared with the literature below. Before lead application, the tree leaf appearance time was obtained from Gm application with the earliest 16.73 days. Also at this stage, the longest hypocotyls were taken from Gm and control applications with 20.27 mm and 19.29 mm. The maximum cotyledon width (11.03 mm) and cotyledon length (30.50 mm) were measured from Gm applications (Table 1). Fytianos et al. (2001) reported that high heavy metal concentrations in the soil can disrupt important physiological functions in plants and may cause food imbalance.
In our study, as the heavy metal density increases, the development of plants and the distribution of the amount of elements changed negatively (Tables 1, 2 Table 2, the highest values were obtained from Gm-0 ppm application. Shoot length, shoot diameter, number of leaves, shoot and root fresh weight, shoot and root dry weight, were measured as 14.27 mm, 2.80 mm, 5.32 pcs / plant, 76.10 g, 13.29 g, 7.64 g, and 1.10 g, respectively in Gm-0 ppm application. Control-0 and control-100 ppm applications follow these values. Şen (2008) observed that Gi applications have positive effects on seedling shoot length, shoot diameter, number of leaves, shoot age weight, shoot dry weight, root fresh weight and root dry weight. In another study conducted by Keskin (2009), it was stated for some of the criteria examined higher values were obtained from Gm application, while for some other criteria Gi application was better. It is similar in our study. The positive interactions of mycorrhizal with those in the Solanaceae family are mentioned in Demir (1998). In our study, it was seen that there was coherence between AMF and eggplant. If we examine Table 3, the application of Gi was better than Gm application for K element uptake. Similarly, the increase in shoot P content (3322.4 ppm) is the highest in Gi-0 ppm application. The root phosphorus content (3682.9 ppm) and nitrogen content (6.69%) has reached the highest values in Gm -800 ppm application. However, in general, when the parameters were examined, it was seen that the data obtained with increasing lead doses in Gi application had higher values than Gm and control. According to these results, the data we obtained shows the efficacy of mycorrhizal in different lead doses. Mycorrhizal symbiosis plays an effective role in the uptake of nitrogen (N), phosphorus (P) and potassium (K), which are essential elements in plant nutrition (Ames et al., 1983;Ortaş, 1998). In the study conducted by Şen (2008), it is reported that the possible negative effects of NaCl on eggplant seedling development and seedling nutrient content can be significantly reduced by Gi applications in salty soil conditions. Similarly, in our study, Glomus intrarasices (Gi) and Gigaspora margarita (Gm) applications significantly reduced the negative effects of Pb. In another study conducted by Dahmani et al., (2000) the major differences in leaf and root concentrations of lead showed a significant restriction in transporting metals from roots to shoots and green leaves. , the intake of elements by roots and leaves of tomato seedlings, was negatively affected by the increase of lead concentration, especially in 300 mg / l Pb. Low lead levels in the plant were found to be 510 mg/kg in the roots, 130 mg/kg in the shoots and 312 mg/kg in the leaves. In addition, medium and high lead application of the plant was found to be 917-1750 mg/kg in leaves, 750-222 mg/kg in shoots and 1438-2520 mg/kg Pb in shoots. Shilev and Babrikov (2005) reported that Solanaceae family plants can take considerable amounts of heavy metals from soil by their roots, leaves and fruits, and the amounts of Pb, Zn and Mn were found to be the highest. Our study shows parallel results with this study. The highest values of Ca (33538.8 ppm in shoot and 24165.6 ppm in root) and Pb (1692.14 ppm in shoot and 29601.6 ppm in root) were obtained from Gm application. As shown in Table 3, Pb content has reached high values in eggplant, and AMF have been found to increase the value of Pb content in shoots and root.

and 3). If we examine the interactions of lead doses and mycorrhizal applications in
The results of Al-Chaarini et al., (2009) showed that the rate of unwashed samples of heavy metal changed from high to undetectable to 3.0904 mg / g. Moreover, in this study leafy vegetables, subsoil vegetables or aboveground vegetables were compared, and it was seen that all heavy metals polluted the leafy vegetables at significantly higher levels. In Ergün and Öncel (2009), it was determined that in bread wheat the inhibition of root and seedling growth was in parallel with the increase of heavy metal concentration and application time. Zengin and Munzuroğlu (2004) reported that copper and lead applied in the form of chlorine salt has a significantly negative effect on the growth of root, stem and leaf of bean seedlings. Dodd and Haas (1983) mentioned indirect effects of mycorrhizal resistance for heavy metal toxicity. Our findings have been parallel to this study.

Conclusion
In our study, the negative effects of lead, which is one of the important heavy metals, on seedling growth and seedling parameters in eggplant were determined. In addition, until control-400 ppm the intake of lead was observed in the eggplant seedling period in both shoot and root. In the control-800 ppm application, the plants did not develop and dried due to the high toxicity of lead. According to the data obtained in our study, AMF was found to be effective in soils containing lead. Glomus intraradices were found to be more effective among mycorrhizal species especially in eggplant