施用产生ACC脱氨酶的植物促生根际细菌枯草芽孢杆菌Rhizo SF 48后番茄耐旱性的诱导

Induction of drought tolerance in tomato upon the application of ACC deaminase producing plant growth promoting rhizobacterium Bacillus subtilis Rhizo SF 48.

作者信息

H G Gowtham, S Brijesh Singh, M Murali, N Shilpa, Prasad Melvin, Aiyaz Mohammed, K N Amruthesh, S R Niranjana

机构信息

Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysuru, 570 006, Karnataka, India.

Applied Plant Pathology Laboratory, Department of Studies in Botany, University of Mysore, Manasagangotri, Mysuru, 570 006, Karnataka, India.

出版信息

Microbiol Res. 2020 Jan 25;234:126422. doi: 10.1016/j.micres.2020.126422.

DOI:10.1016/j.micres.2020.126422

PMID:32058314

Abstract

A total of ten 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing PGPR isolates were selected and evaluated for the induction of drought stress tolerance in tomato. Among the selected PGPR, maximum seed (laboratory) and plant growth promotion (greenhouse) was observed in tomato seeds bacterized with Bacillus subtilis Rhizo SF 48. The genomic study confirmed the presence of ACC deaminase gene in Rhizo SF 48 and the obtained sequence was deposited to the NCBI database with the Accession No. MK652706. The tomato plants grown upon treatment with Rhizo SF 48 significantly enhanced plant growth even after exposing to different levels of drought stress as compared to stress induced control plants. About 7.5% and 38% increase in RWC were observed in Rhizo SF 48 treated tomato plants grown under well-watered and stress conditions (S4) compared to their control plants, respectively. An increase of 0.76, 0.23 and 0.78 fold in proline, SOD and APX activity and a decrease of 0.3 fold in MDA and HO contents were observed in Rhizo SF 48 treated plants compared to control plants grown under S4 conditions. The histo-chemical studies showed lower accumulations of HO and superoxide anion in the leaves of Rhizo SF 48 treated plants under drought stress, which was in confirmation with the quantification results of HO and SOD. The qRT-PCR studies on drought (Le25) and ethylene responsive factor (SlERF84) marker genes showed that a significant decrease of 0.75 and 0.81 folds, respectively in Le25 and SlERF84 accumulation was observed in Rhizo SF 48 treated plants compared to untreated plants grown under S4 conditions. From the results, it can be attributed that ACC deaminase producing Rhizo SF 48 was able to protect tomato plants against oxidative damage caused due to drought stress and enhanced plant growth promotion. It can be concluded that ACC deaminase producing Rhizo SF 48 can serve as a useful bio-inoculant for sustainable tomato production in arid and semi-arid regions with water deficit.

摘要

总共挑选了10株产生1-氨基环丙烷-1-羧酸（ACC）脱氨酶的植物根际促生细菌（PGPR）分离株，并对其诱导番茄耐旱性的能力进行了评估。在所挑选的PGPR中，用枯草芽孢杆菌Rhizo SF 48处理的番茄种子表现出最大程度的种子（实验室条件下）和植株生长促进作用（温室条件下）。基因组研究证实Rhizo SF 48中存在ACC脱氨酶基因，所得序列已存入NCBI数据库，登录号为MK652706。与受胁迫诱导的对照植株相比，用Rhizo SF 48处理后的番茄植株即使在遭受不同程度的干旱胁迫后，其生长仍显著增强。与对照植株相比，在水分充足和胁迫条件（S4）下生长的经Rhizo SF 48处理的番茄植株，其相对含水量（RWC）分别增加了约7.5%和38%。与在S4条件下生长的对照植株相比，经Rhizo SF 48处理的植株中脯氨酸、超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）活性分别增加了0.76、0.23和0.78倍，丙二醛（MDA）和过氧化氢（HO）含量降低了0.3倍。组织化学研究表明，在干旱胁迫下，经Rhizo SF 48处理的植株叶片中HO和超氧阴离子的积累较少，这与HO和SOD的定量结果一致。对干旱（Le25）和乙烯响应因子（SlERF84）标记基因的qRT-PCR研究表明，与在S4条件下生长的未处理植株相比，经Rhizo SF 48处理的植株中Le25和SlERF84的积累分别显著降低了0.75倍和0.81倍。从结果可以推断，产生ACC脱氨酶的Rhizo SF 48能够保护番茄植株免受干旱胁迫引起的氧化损伤，并促进植株生长。可以得出结论，产生ACC脱氨酶的Rhizo SF 48可作为一种有用的生物接种剂，用于缺水的干旱和半干旱地区的番茄可持续生产。