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The ex vitro acclimatization process plays an important role in plant micropropagation. In vitro plantlets have to rapidly adapt to environmental changes. The current work aimed at assessing some physiological and biochemical changes of micropropagated Dendrobium anosmum Lindl. Plantlets during ex vitro acclimatization process, eg. contents of water (leaf relative water content), dry matter, proline and photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoid), chlorophyll fluorescence and antioxidant enzymes (peroxidase và catalase) activities. The analyzed results showed that water content decreased in acclimatized plantlets compared to in vitro ones. The chlorophylls and carotenoids contents of what were significantly higher in ex vitro plantlet leaves compared to the day 0 plantlets. The pigment contents were observed to increase during the ex vitro acclimatation process. When the plantlets were moved out of the in vitro medium, the maximum photochemical efficiency of photosystem II (Fv/Fm) significantly decreased at the early acclimatation points then restored at the end of acclimatation process. The content of proline and activities of antoxidant enzymes significantly increased with different periods of acclimatation process. The proline content and enzyme activities were recorded at the first ex vitro period when most water loss occurred in plantlets. These results suggest that Dendrobium anosmum Lindl in vitro plantlets have adapted to the transplantation by possesing some physiological responses of its photosynthetic system as well as its antioxidant machinery.

The NIN-like proteins (NLP) belong to RWP-RK transcription factor family and possess the similarity characteristics of NIN (Nodules INception). The NLPs regulate the expression of genes which are involved in nitrate signaling in plants. In this work, we have performed a genome-wide analysis of the NLP gene family in maize (Zea mays L.) through the bioinformatic methods. We identified a total of nine NLP encoding genes in whole genome of maize. The genomic sequences of these genes were from 2855 to 8092 nucleotides in length and contained three or four introns. Their predicted protein sizes ranged in size from 786 to 945 amino acids. The theoretical isoelectric point values of most deduced protein were less than 7. The maize NLP proteins possessed conserved regions of plant NLP at N-terminal as well as at C-terminal including the RWP-RK and PB1 domains. Based on the phylogenic analysis, we detected three current whole-genome gene duplication events which occurred in maize genome apter speciation point. All of NLP genes expressed in tissues at different development stages, from germinating seed to maturation seed were examined. The ZmNLP5, ZmNLP6 and ZmNLP7 were weakly expressed in comparison to others genes in most examined tissues.

Galactinol synthases (GolS, EC 2.4.1.123) belong to the glycosyltransferase 8 family. These enzymes catalyzes galactosylation of myo-inositol to form galactinol, precursor of raffinose which is solube sucrose playing an important role in stress tolerance in plants. We identified and analyzed a total of three GolS encoded genes in the whole genome of common bean. These genes possessed two or three introns. The predicted proteins contained from 322 to 340 amino acids. The common bean GolS proteins contained all conseved motifs that were characterized for other previously known GolSs. These proteins were acidic and weakly hydrophilic. The phylogenic tree constructed from GolS proteins of Arabidopsis, poplar and common bean showed that only one gene duplication event was detected in the commone bean genome. Common bean GolS genes expressed in all vegetative and reproductive tissues. However, the transcript abundances of each gene varied in different tissues. When comparing the expression levels of these three genes as defined RNAseq, we found that the expression level of PvGolS2 was the lowest, PvGolS1 expressed the strogest leaves and stem, while PvGolS3 expressed in roots and nodules. We discovered that Rhizobium incubation affected on the expression of GolS genes for the first time. In the reproductive tissues, PvGolS1 expressed in most studied tissues. Its expression level correlatively increased with the tissue development.

In this work, some physiological parameters of micropropagated Bac Kan local alpinia (Alpinia coriandriodora D. Fang) affected by drought and salicylic acid treatments under drought condition were analyzed. In comparison to well watered plants, the droughted plants have lower contents of relative water, photosynthetic pigments, anthocyanins in leaves and Fv/Fm ratio. In constrat, proline content and activity of both catalase and peroxidase are higher in droughted plants. SA treatments, 10 M in particular, attenuate damages in droughted alpinia plants by affecting on some physiological parameters. An increase in content of relative water, photosynthetic pigments (chlorophylls and carotenoids), and anthocyanins were observed in leaves of treated plants in comparison to non-treated plants under drought condition. Fv/Fm ratio and peroxidase activity are higher in 10 M SA-treated plants than non-treated ones. Both 10 M and 100 M SA treatments lead to a decrease in proline accumulation and catalase activity in leaves of droughted plants.