Ece Turhan, Ş.Şebnem Ellialtıoğlu, Sevinç Kıran, Volkan Alveroğlu, Şebnem Kuşvuran, Çağla Ateş Turkey

Transkript

1 Ece Turhan, Ş.Şebnem Ellialtıoğlu, Sevinç Kıran, Volkan Alveroğlu, Şebnem Kuşvuran, Çağla Ateş Turkey

2 Over 20% of irrigated land is affected by salinity (Rozema and Flowers, 2008) In arid and semiarid regions of the world, Also less extreme environments

3 Osmotic effects Nutritional effects Toxic effects Secondary stress Primary stress

4 Salt stress is complex and imposes a water deficit because of osmotic effects on a wide variety of metabolic activities the formation of reactive oxygen species (ROS) in plants

5 ROS accumulate during stress and may lead to cell injury and death. However, ROS are also used by cells as secondary messengers involved in the stress-response signal transduction pathway.

6 Plants use two major strategies to control the level of ROS and prevent cellular damage: Scavenge of ROS by anti-oxidants and anti-oxidative enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and glutathione reductase (GR) (Mittler et al 2004). Lower the rate of ROS production in cells by supressing ROS-producing reactions and by different stress avoidance strategies.

7 Under salinity stress the amount of 1- aminocyclopropane-1-carboxylate (ACC), a precursor for ethylene production in plants, increases. seed germination and root growth may decrease (Belimov et al., 2001; Saravanakumar and Samiyappan, 2007).

8 Traditional breeding programmes Genetic transformation Use of saline water in irrigated agriculture Tolerant cultivars, Several cultural practices, Some of the proposed practices, The application of chemical amendments or leaching salts to deeper soil layers One environment-friendly technique is grafting The use of plant growth promoting bacteria (PGPRs)

9 better growth and yield, higher photosynthesis and leaf water content, greater root-to-shoot ratio, higher accumulation of compatible osmolytes, abscisic acid and polyamines in leaves, greater antioxidant capacity in leaves, lower accumulation of Na + and/or Cl - in shoots than ungrafted or self-grafted plants (Colla et al. 2010).

10 Many researchers have noted the positive effects of the ACC deaminaseproducing bacteria in the rhizosphere in alleviating different stresses including salinity on plant growth (Cheng et al., 2007; Saravanakumar and Samiyappan, 2007). PGPR includes bacteria belonging to the genera Azotobacter, Azospirillum, Arthrobacter, Bacillus, Burkholderia, Klebsiella, Pseudomonas and Serratia (Vessey 2003). Plant Growth-Promoting Rhizobacteria (PGPR) (Maheshvari, 2012)

11 Rhizobacteria mediated metabolic responses in plants (Maheshvari, 2012)

12 The objective of this work was to evaluate the effect of grafting on a salt-tolerant rootstock and inoculation with the 1- aminocyclopropane-1-carboxylate (ACC)- deaminase (EC ) containing bacteria on eggplant growth, mineral uptake and activities of the antioxidant enzymes including SOD, CAT, APX and GR of plant leaves under salinity stress. 12

13 A salt-tolerant eggplant rootstock: cv.vista- 306 As scions: Two salt-tolerant eggplant genotypes; Mardin Kızıltepe, Burdur Merkez and two salt-sensitive eggplant genotypes; Artvin Hopa, Kemer. ACC Deaminase containing bacteria: Serratia marcescens 13

14 The bacteria were isolated from the rhizosphere soil samples from graminae plants growing in Eskisehir, Turkey according to Dworkin and Foster (1958). The selected strains of the bacteria were stored at 20 C with 20% glycerol. ACC-deaminase activity was determined as described by Honma and Shimomura (1978). PGPR were identified by using the Vitek 2 microbial identification system in Nevşehir Public Health Laboratory. 14

15 Grafted and non-grafted seedlings with 4-5 true leaves were transferred to pots filled with a mixture of peat and perlite (2:1) in a controlled greenhouse (23-25 C, approximately 50-55% relative humidity).

16 Treatment Rootstock Genotype Control Non-grafted Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer Vista-306 Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer NaCl Non-grafted Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer Vista-306 Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer NaCl+S Non-grafted Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer Vista-306 Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer

17 After 10 days from planting, 20 ml bacteria solution (cell density of 3x10 8 cells/ml) per plant was applied to root region of the seedlings as inoculum (Alveroğlu, 2014). Salt solution; 200 mm NaCl was applied, after 5 days from inoculation of the bacteria. 17

18 Shoot fresh weight, shoot dry weight (Dasgan and Koç, 2009; Kuşvuran, 2010) Stem length, leaf area and SPAD values Lipid peroxidation was estimated by determining the malondialdehyde (MDA) content in the leaves according to the method of Lutts et al. (1996). The MDA concentration was determined using an extinction coefficient of 155 mm. 18

19 Na + K +, Ca ++ and Cl contents of the dried samples digested in concentrated 0.1 N nitric acid (HNO 3 ) and perchloric acid (HClO) (4:1) were determined by flame photometry (Kusvuran 2004). Chloride (Cl) was determined by titration method with 0.1 N AgNO 3 (Kacar ve İnal, 2008). 19

20 SOD activity was assayed using NBT method (measured at 560 nm) (Giannapolitis and Ries, 1977). CAT was assayed from the crude extract by monitoring the consumption of H 2 O 2 at 240 nm (Rao et.al. 1996). APX activity was determined by measuring decrease in absorbance of the oxidised ascorbate at 290 nm, according to Nakano and Asada (1980). GR activity was determined by following the oxidation of β-nicotinamide adenine dinucleotide phosphate (NADPH) at 340 nm (extinction coefficient 6.2 mm/cm) (Cakmak and Marschener, 1992). 20

21 The data were subjected to an analysis of variance using the MSTAT-C package program (Freed et al.,1989) and mean separation was accomplished using the LSD test at p 0.05.

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23 Non-grafted Vista-306 Non-grafted Vista-306 Non-grafted Vista-306 Non-grafted Vista-306 Shoot Dry Weight (mg plant -1 ) Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer Control NaCl NaCl+S

24 Treatment Rootstock Genotype Shoot Fresh Weight (g plant -1 ) Control Non-grafted Mardin Kızıltepe de de Burdur Merkez gh j Artvin Hopa fg gh Kemer d de Vista-306 Mardin Kızıltepe fg j Burdur Merkez ef g-ı Artvin Hopa fg d Kemer ı h-j NaCl Non-grafted Mardin Kızıltepe hı ef Burdur Merkez fg d Artvin Hopa ı h-j Kemer hı fg Vista-306 Mardin Kızıltepe c a Burdur Merkez hı n Artvin Hopa fg m Kemer bc ab NaCl+S Non-grafted Mardin Kızıltepe gh n Burdur Merkez de lm Artvin Hopa a bc Kemer hı m Vista-306 Mardin Kızıltepe ef kl Burdur Merkez ab c Artvin Hopa gh k Kemer ef ıj LSD (%5) Shoot Dry Weight (mg plant -1 )

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26 Treatment Rootstock Genotype Stem length (cm) Leaf area (cm 2 ) Control Non-grafted Mardin Kızıltepe a-e a Burdur Merkez g-ı fg Artvin Hopa b-f d-f Kemer a a Vista-306 Mardin Kızıltepe c-h c-f Burdur Merkez a-c bc Artvin Hopa a-e a Kemer e-ı fg NaCl Non-grafted Mardin Kızıltepe c-h d-f Burdur Merkez a-e ab Artvin Hopa e-ı e-g Kemer c-g cd Vista-306 Mardin Kızıltepe a a Burdur Merkez hı hı Artvin Hopa d-h gh Kemer ab ab NaCl+S Non-grafted Mardin Kızıltepe g-ı e-g Burdur Merkez b-f c-e Artvin Hopa a a Kemer f-ı k Vista-306 Mardin Kızıltepe c-h ı-k Burdur Merkez a-d ab Artvin Hopa ı jk Kemer c-h h-j LSD (%5)

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28 Treatment Rootstock Genotype Chlorophyll (SPAD value) MDA (µ mol/g FW) Control Non-grafted Mardin Kızıltepe a 1.84 mn Burdur Merkez cd 2.39 l Artvin Hopa b-d 2.26 lm Kemer a 1.71 n Vista-306 Mardin Kızıltepe b-d 1.71 n Burdur Merkez bc 1.58 n Artvin Hopa a 1.94 mn Kemer d 1.84 mn NaCl Non-grafted Mardin Kızıltepe b-d 5.23 ıj Burdur Merkez a 5.90 g Artvin Hopa cd 8.61 c Kemer b 9.68 a Vista-306 Mardin Kızıltepe a 4.84 jk Burdur Merkez e 5.13 ıj Artvin Hopa e 7.74 de Kemer a 7.26 f NaCl+S Non-grafted Mardin Kızıltepe cd 5.42 hı Burdur Merkez b 5.81 gh Artvin Hopa a 8.03 d Kemer g 9.06 b Vista-306 Mardin Kızıltepe fg 4.65 k Burdur Merkez a 5.29 l Artvin Hopa f 7.29 f Kemer e 7.48 ef LSD(%5)

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32 Treatment Rootstock Genotype Na(%) Cl(%) K(%) Ca(%) Control Non-grafted Mardin Kızıltepe 0.57 kl 0.11 j Burdur Merkez 0.57 kl 0.21 b Artvin Hopa 0.47 o 0.15 f Kemer 0.50 n 0.11 j Vista-306 Mardin Kızıltepe 0.53 m 0.15 f Burdur Merkez 0.48 o 0.13 h Artvin Hopa 0.50 n 0.11 j Kemer 0.68 ef 0.21 b NaCl Non-grafted Mardin Kızıltepe 0.69 f 0.16 e Burdur Merkez 0.72 d 0.06 l Artvin Hopa 0.66 gh 0.17 d Kemer 0.82 a 0.16 e Vista-306 Mardin Kızıltepe 0.67 fg 0.12 ı Burdur Merkez 0.56 l 0.21 b Artvin Hopa 0.78 c 0.16 e Kemer 0.80 b 0.12 ı NaCl+S Non-grafted Mardin Kızıltepe 0.64 ıj 0.20 c Burdur Merkez 0.65 hı 0.14 g Artvin Hopa 0.64 ıj 0.09 k Kemer 0.67 fg 0.16 e Vista-306 Mardin Kızıltepe 0.58 k 0.14 g Burdur Merkez 0.54 m 0.12 ı Artvin Hopa 0.65 hı 0.24 a Kemer 0.63 j 0.21 b LSD (%5)

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35 APX(µ mol/ min/mg FW) Non-grafted Vista-306 Non-grafted Vista-306 Non-grafted Vista-306 Non-grafted Vista Mardin Kızıltepe Burdur Merkez Artvin Hopa Kemer Control NaCl NaCl+S

36 Treatment Rootstock Genotype SOD (U/min/mg FW) CAT (µ mol/ min/mg FW) GR (µ mol/ min/mg FW) APX (µ mol/min/mg FW) Control Non-grafted Mardin Kızıltepe n-p m Burdur Merkez lm h-m Artvin Hopa pq j-m Kemer ı f-k Vista-306 Mardin Kızıltepe m-o c-e Burdur Merkez o-q lm Artvin Hopa q k-m Kemer l-n ı-m NaCl Non-grafted Mardin Kızıltepe d-f c-f Burdur Merkez ef d-ı Artvin Hopa k g-l Kemer jk e-j Vista-306 Mardin Kızıltepe c bc Burdur Merkez de ı-m Artvin Hopa ıj f-l Kemer gh f-l NaCl+S Non-grafted Mardin Kızıltepe c a Burdur Merkez d cd Artvin Hopa ı-k d-j Kemer jk d-j Vista-306 Mardin Kızıltepe a ab Burdur Merkez b c-g Artvin Hopa hı d-j Kemer fg c-h LSD(%5)

37 Shoot FW and DW, stem length, leaf area and SPAD values were adversely affected by salt stress, but generally salt-tolerant genotypes were comparatively less affected. Sodium (Na + ) and Cl contents in the leaves were significantly enhanced. Malondialdehyde (MDA) content, the activities of CAT, GR, APX and SOD in the leaf tissues increased in salt stress conditions. 37

38 Significant differences in cultivar level. The grafted seedlings induced salt tolerance Inoculation of the bacteria significantly counteracted the salt-induced adverse effects on growth characteristics, leaf K +, Ca ++, Cl, Na +, MDA content and antioxidative enzyme activities. 38

39 To conclude, grafted and Serratia marcescens-inoculated eggplants have a positive effect on growth of eggplant seedlings under salt stress. Based on these findings, beside grafting method, the biological treatments may help alleviate the negative effect of salinity on the growth of eggplant seedlings. 39

40 There are no results about yield and fruit quality. In addition, almost no molecular studies regarding the effects of salt on Serratiaeggplant interactions have been carried out so far. 40

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