본 연구에서는 내건성 식물 선발을 위한 최적 인자를 구명하고, 이들 내건성 식물들의 생장특성을 조 사하였다. 건조저항인자에 대한 나머지 건조저항일(RD), 엽면적(LD), 단위증산량(UTR), 상대함수량 (RWC), 상대수분손실량(RWL), 엽면적(LA), 기공수(SN) 및 기공면적(SA) 등 6개 인자들을 비교한 결과 상대수분손실량과 단위증산량이 건조저항일에 많은 영향을 주는 것으로 나타났다. PCA분석 결과 SA, LA, RD는 한그룹으로 RWC와 SN은 다른 한 그룹으로 구분되었고, UTR은 SA, LA와, RWL은 RWC와 SN과 음의 상관을 보였다. 상기 결과를 종합하여 느릅나무, 도깨비바늘, 뚝갈, 매듭풀, 새, 더위지기, 맑은대쑥, 독말풀, 긴담배풀, 소리쟁이, 비수리, 장구채, 개기장, 도깨비가지를 내건성 식물 종으로 선 발하였고, 이들에 대한 생장시험을 수행하였다. 절토사면지에서 내건성 식물의 줄기생장은 식물 종간에 약간의 차이를 보였는데, 줄기생장과 잎의 수는 느릅나무를 제외하고 폿트에서는 차이를 보이지 않았 다. 그러나 절토사면지에서 내건성 식물 뿌리 생장과 T/R율은 폿트생장과 큰 차이를 보였고, 특히 T/R 율은 폿트묘보다 월등히 낮았다. 이 결과로 보아 선발된 내건성 식물은 절토사면지와 같이 척박한 토양 에서도 잘 적응할 것으로 나타나 내건성 식물의 육종 등에 이용될 수 있을 것으로 판단된다.

The MethioninesulfoxidereductaseB2(MsrB2) gene catalyzes the reduction of free and protein-bound methionine sulfoxide to methionine and is known to provide tolerance to biotic and abiotic environmental stresses. There have yet to be any reports that MsrB2 enhances drought tolerance. Two drought-tolerant transgenic rice lines, L-8 (single copy) and L-23 (two copy), expressing the Capsicum annuum MsrB2 (CaMsrB2) gene were selected for stress tolerance phenotyping under drought stress conditions. CaMsrB2 enhanced relative water content (RWC), maintained substantial quantum yield (Fv/Fm ratio), and subsequently improved photosynthetic pigments. Interestingly, L-23, carrying two-copy T-DNA insertion, showed greater drought tolerance through more effective stomatal regulation, carotenoid concentration, and osmotic potential than the wild type. High-tech infrared technology (FLIR SC620) was used for the selection of stress-tolerant physiotypes. Later, the IR results were correlated with other tested physiological parameters. The IR images, average plant temperature, and physiological parameters of the treated plants were discussed in detail.

The perturbation of the steady state of reactive oxygen species due to biotic and abiotic stresses in a plant could lead to protein denaturation through the modification of amino acid residues, including the oxidation of methionine residues. Methionine sulfoxide reductases (MSRs) catalyze the reduction of methionine sulfoxide back to the methionine residue. To assess the role of this enzyme, we generated transgenic rice using a pepper CaMSRB2 gene under the control of the rice Rab21 promoter with/without a selection marker, the bar gene. A drought resistance test on transgenic plants showed that CaMSRB2 confers drought tolerance to rice, as evidenced by less oxidative stress symptoms and a strengthened PSII quantum yield under stress conditions, and increased survival rate and chlorophyll index after the re-watering. The results from immunoblotting using a methionine sulfoxide antibody and nano-LC-MS/MS spectrometry suggest that porphobilinogen deaminase (PBGD), which is involved in chlorophyll synthesis, is a putative target of CaMSRB2. The oxidized methionine content of PBGD expressed in E. coli increased in the presence of H2O2, and the Met-95 and Met-227 residues of PBGD were reduced by CaMSRB2 in the presence of dithiothreitol. An expression profiling analysis of the overexpression lines also suggested that photosystems are less severely affected by drought stress. Our results indicate that CaMSRB2 might play an important functional role in chloroplasts for conferring drought stress tolerance in rice

Transgenic cymbidium plants containing drought and salt stresses tolerance genes were produced by using a highly efficient Agrobacterium-mediated transformation system. The gene (AtSZF2) is salt and drought stresses tolerant gene and transferred into cymbidium plants. These transgenic cymbidium plants are investigated for gene introduction by PCR and analyzed by salt and drought stresses to check its gene expression. To investigate the gene expression of AtSZF2, leaves of transgenic cymbidium plants were soaked in salt solution (200 mM NaCl). Also, transgenic cymbidium plants were kept under no watering for 6 weeks to check the expression of drought stress tolerance. As a result, wild type plants showed more damage than transgenic plants under salt treatment. Further, transgenic cymbidium plants retained green color and healthy status, while wild type plants showed no tolerance after 6 weeks of no-watering treatment.