Domates genotiplerinin kuraklık stresine toleransını artırmada kök bakterilerinin etkisi
Küçük Resim Yok
Tarih
2021
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Ege Üniversitesi, Fen Bilimleri Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışma TÜBİTAK (117O126) projesi kapsamında, Türkiye'nin farklı illerinde yetiştirilen domates bitkilerinden izole edilen yerel kök bakterilerinin (KB) domates bitkilerinin kuraklığa toleransı üzerine etkilerini belirlemek; etki mekanizmalarını morfolojik, fizyolojik ve biyokimyasal testler ile ortaya koymak amacıyla yürütülmüştür. Denemeler tohum çimlenme ve genç bitki aşamasında PEG 6000 kaynaklı kuraklık stresi altında gerçekleştirilmiştir. In vitro tohum çimlendirme ve in vivo su kültürü yetiştiricilik testleri içeren çalışma tam kontrollü bitki yetiştirme odasında üç aşamalı olarak gerçekleştirilmiştir: (1) Test edilecek domates genotiplerinin seçimi, (2) Test edilecek kök bakterilerinin seçimi, (3) Kök bakterilerinin domateste kuraklık stresine etkilerinin belirlenmesi. Çalışmada test edilen domatesler Ege Tarımsal Araştırma Enstitüsü Ulusal Gen Bankası'ndan temin edilen "yerel domates genotipleri" ve "ticari oturak domates çeşitleri" ve "ticari sırık domates çeşitleri" olmak üzere 3 grupta toplanmıştır. Test edilecek domates genotiplerinin ve KB'lerinin seçiminde ön tarama tohum çimlendirme testi ile yapılmış ve ardından seçilen genotipler veya KB'leri su kültürü ile genç bitki aşamasında değerlendirilmiştir. Tohum çimlendirme denemelerinde kuraklık stresi %4'lük PEG 6000 çözeltisi ile yaratılmış ve 14.günde kök ve sürgün uzunluğu, yaş ağırlık, çimlenme yüzdesi belirlenmiş ve vigor indeksi hesaplanmıştır. Su kültürü denemelerinde kuraklık dozu olarak Ψs= -1.0 MPa kullanılmış, su kültürüne alınan 2-3 gerçek yapraklı fideler 7 gün kontrol uygulamasında tutulduktan sonra kuraklık dozuna kademeli olarak (¼,½, ¾ ve tam doz) her 48 saatte bir artırılarak ulaşılmıştır. Tam doz (-1.0 MPa) uygulamasından 48 saat sonra alınan örneklerde morfolojik ve fizyolojik özellikler belirlenmiştir. Kuraklık stresi altında kontrole kıyasla incelenen özelliklerde meydana gelen değişim oranları dikkate alınarak "Tartılı derecelendirme" yapılmıştır. Tohum çimlendirme testinde genotiplerin seçiminde kullanılan vigor indeksinde % değişim değerleri ile su kültürüne ait Tartılı Derecelendirme toplam puanları arasındaki korelasyonun yerel genotiplerde (r:0.825) ve oturak çeşitlerde (r: 0.709) yüksek düzeyde, sırık çeşitlerde (r: 0.564) orta düzeyde olduğu tespit edilmiştir. TÜBİTAK projesi (117O126) kapsamında izole edilen 49 yerel KB izolatı arasından tohum çimlendirme testi sonrasında seçilen 12 KB izolatı kurağa hassas olarak belirlenen MSC-50 ve Panzer çeşitlerinin genç bitki aşamasında kurağa toleransı üzerine etkileri bakımından değerlendirilmiş ve test edilen çeşitlerin kurağa toleransını artıran 3 KB izolatı (113: Bacillus megaterium isolate NUC-, 204: Bacillus aryabhattai strain NIHHS133, 337: Bacillus cereus strain BBS7) belirlenmiştir. Çalışmanın son aşamasında, belirlenen KB izolatlarının seçilen yerel (kurağa tolerant: TR70707, kurağa hassas: TR40430), ticari oturak (kurağa tolerant:Vitamin, kurağa hassas: MSC-50) ve ticari sırık (kurağa tolerant:Nazar, kurağa hassas:Panzer) domates genotiplerinin kurağa tolaransı üzerine etkileri genç bitki aşamasında değerlendirilmiştir. KB inokulasyonun morfolojik özellikler üzerine etkisi önemli bulunmamakla birlikte fizyolojik ve biyokimyasal özellikler KB uygulamasından etkilenmiştir. KB inokulasyonu kuraklık stresine maruz kalan genç domates bitkilerinin yapraklarında prolin konsantrasyonu ile süperoksit dismutaz, katalaz, askorbatperoksidaz enzim aktiviteleri ve askorbik asit miktarını artırmış, malondialdehit seviyesini ise azaltmıştır. Ayrıca test edilen tüm genotiplerde olmamakla birlikte, kurak koşullar altında KB inokulasyonu membran geçirgenliğinde azalışa, klorofil ve karatenoid içeriğinde artışa yol açmıştır. KB inokulasyonunun domates bitkilerinin kuraklık stresine toleransını artırmada etkili olduğu sonucuna varılmıştır.
This study was conducted to determine the effects of native rhizobacteria (RB) against drought stress in tomato plants and to reveal the mechanisms of action through morphological, physiological and biochemical tests. The tested RB were isolated from tomato plants grown in different regions in Turkey within the scope of TUBITAK Project (contract no: 117O126). The experiments were carried out under drought stress created by PEG 6000 at seed germination and young plant stages in growth chamber. The study included 3 main steps: (1) Selection of tomato genotypes to be tested, (2) Selection of RB to be tested, (3) Determination of the effects of RB against drought stress in tomato genotypes. The tomato genotypes tested in the study were categorized in 3 groups as "local tomato genotypes"provided from the National Gene Bankin Izmir and "commercial determinate tomato varieties" and "commercial indeterminate tomato varieties". In theselection of tomato genotypes and RB to be tested, pre-screening was performed by in vitroseed germination test and then the selected genotypes or RB were evaluated at the young plant stage in water culture. In in vitro tests, drought stress was induced by 4% PEG 6000 solution, and after 14 days data regarding to germination percentage, lengths of root and shoot, fresh weight of seedlings were determined and vigor index was calculated. In in vivo experiments by using water culture, drought dose was used as Ψs= -1.0 MPa (full dose) and gradually increased (¼, ½, ¾ and full dose) every 48 hours from 7 days after planting. Forty-eight hours after the full dose application, morphological and physiological properties of the plants were determined. The genotypes tested were classified by weighted ranking method, based on the changes in the PEG treatment compared to the control. The correlations for the relationships between the variations (%) of in vitrovigour index used in the selection of genotypes in the seed germination test and the total scores of weighted ranking in water culture were high for local genotypes (r: 0.825) and determinate varieties (r: 0.709), and moderate for indeterminate varieties (r: 0.564).12 RB isolates were selected according to the results of seed germination test among 49 native RB isolates. These RB were tested on drought sensitive tomato varieties (MSC-50 and Panzer) at the young plant stage, and 3 RB isolates (113: Bacillus megaterium isolate NUC-, 204: Bacillus aryabhattaistrain NIHHS133, 337: Bacillus cereus strain BBS7) were determined to increase drought tolerance of the tested varieties. At the last stage of the study, influence of these RB were evaluated to alleviate drought tolerance of selected tomato genotypes TR70707, Vitamin and Nazar as drought tolerant and TR40430, MSC-50 and Panzer as drought sensitive among local genotypes, and commercial determinate and indeterminate varieties, respectively. Although RB inoculation had no significant effect on morphological properties, physiological and biochemical properties have been affected by the application of RB. RB inoculation increased proline concentration and enzyme activities of superoxide dismutase, catalase, ascorbate peroxidase and amount of ascorbic acid and decreased the level of malondialdehyde in leaves of young tomato plants exposed to drought stress. In addition, although not in all tested genotypes, RB inoculation led to a decrease in membrane permeability and an increase in chlorophyll and carotenoid content under drought stress conditions. It was concluded that RB inoculation is effective in increasing the tolerance of tomato plants against drought stress.
This study was conducted to determine the effects of native rhizobacteria (RB) against drought stress in tomato plants and to reveal the mechanisms of action through morphological, physiological and biochemical tests. The tested RB were isolated from tomato plants grown in different regions in Turkey within the scope of TUBITAK Project (contract no: 117O126). The experiments were carried out under drought stress created by PEG 6000 at seed germination and young plant stages in growth chamber. The study included 3 main steps: (1) Selection of tomato genotypes to be tested, (2) Selection of RB to be tested, (3) Determination of the effects of RB against drought stress in tomato genotypes. The tomato genotypes tested in the study were categorized in 3 groups as "local tomato genotypes"provided from the National Gene Bankin Izmir and "commercial determinate tomato varieties" and "commercial indeterminate tomato varieties". In theselection of tomato genotypes and RB to be tested, pre-screening was performed by in vitroseed germination test and then the selected genotypes or RB were evaluated at the young plant stage in water culture. In in vitro tests, drought stress was induced by 4% PEG 6000 solution, and after 14 days data regarding to germination percentage, lengths of root and shoot, fresh weight of seedlings were determined and vigor index was calculated. In in vivo experiments by using water culture, drought dose was used as Ψs= -1.0 MPa (full dose) and gradually increased (¼, ½, ¾ and full dose) every 48 hours from 7 days after planting. Forty-eight hours after the full dose application, morphological and physiological properties of the plants were determined. The genotypes tested were classified by weighted ranking method, based on the changes in the PEG treatment compared to the control. The correlations for the relationships between the variations (%) of in vitrovigour index used in the selection of genotypes in the seed germination test and the total scores of weighted ranking in water culture were high for local genotypes (r: 0.825) and determinate varieties (r: 0.709), and moderate for indeterminate varieties (r: 0.564).12 RB isolates were selected according to the results of seed germination test among 49 native RB isolates. These RB were tested on drought sensitive tomato varieties (MSC-50 and Panzer) at the young plant stage, and 3 RB isolates (113: Bacillus megaterium isolate NUC-, 204: Bacillus aryabhattaistrain NIHHS133, 337: Bacillus cereus strain BBS7) were determined to increase drought tolerance of the tested varieties. At the last stage of the study, influence of these RB were evaluated to alleviate drought tolerance of selected tomato genotypes TR70707, Vitamin and Nazar as drought tolerant and TR40430, MSC-50 and Panzer as drought sensitive among local genotypes, and commercial determinate and indeterminate varieties, respectively. Although RB inoculation had no significant effect on morphological properties, physiological and biochemical properties have been affected by the application of RB. RB inoculation increased proline concentration and enzyme activities of superoxide dismutase, catalase, ascorbate peroxidase and amount of ascorbic acid and decreased the level of malondialdehyde in leaves of young tomato plants exposed to drought stress. In addition, although not in all tested genotypes, RB inoculation led to a decrease in membrane permeability and an increase in chlorophyll and carotenoid content under drought stress conditions. It was concluded that RB inoculation is effective in increasing the tolerance of tomato plants against drought stress.
Açıklama
Anahtar Kelimeler
Kök Bakterisi, PEG 6000, Su Stresi, Domates, Prolin, Antioksidan Enzim Aktivitesi, Rhizobacteria, PEG 6000, Water Stress, Tomato, Proline, Antioxidant Enzyme Activity
