Overexpression of phytochrome A and its hyperactive mutant improves shade tolerance and turf quality in creeping bentgrass and zoysiagrass

Ganesan, Markkandan,Han, Yun-Jeong,Bae, Tae-Woong,Hwang, Ok-Jin,Chandrasekkhar, Thummala,Shin, Ah-Young,Goh, Chang-Hyo,Nishiguchi, Satoshi,Song, In-Ja,Lee, Hyo-Yeon,Kim, Jeong-Il,Song, Pill-Soon Springer-Verlag 2012 Planta Vol.236 No.4

<P>Phytochrome A (phyA) in higher plants is known to function as a far-red/shade light-sensing photoreceptor in suppressing shade avoidance responses (SARs) to shade stress. In this paper, the Avena PHYA gene was introduced into creeping bentgrass (Agrostis stolonifera L.) and zoysiagrass (Zoysia japonica Steud.) to improve turf quality by suppressing the SARs. In addition to wild-type PHYA, a hyperactive mutant gene (S599A-PHYA), in which a phosphorylation site involved in light-signal attenuation was removed, was also transformed into the turfgrasses. Phenotypic traits of the transgenic plants were compared to assess the suppression of SARs under a simulated shade condition and outdoor field conditions after three growth seasons. Under the shade condition, the S599A-PhyA transgenic creeping bentgrass plants showed shade avoidance-suppressing phenotypes with a 45?% shorter leaf lengths, 24?% shorter internode lengths, and twofold increases in chlorophyll concentrations when compared with control plants. Transgenic zoysiagrass plants overexpressing S599A-PHYA also showed shade-tolerant phenotypes under the shade condition with reductions in leaf length (15?%), internode length (30?%), leaf length/width ratio (19?%) and leaf area (22?%), as well as increases in chlorophyll contents (19?%) and runner lengths (30?%) compared to control plants. The phenotypes of transgenic zoysiagrass were also investigated in dense field habitats, and the transgenic turfgrass exhibited shade-tolerant phenotypes similar to those observed under laboratory shade conditions. Therefore, the present study suggests that the hyperactive phyA is effective for the development of shade-tolerant plants, and that the shade tolerance nature is sustained under field conditions.</P>

A Simple and Reproducible Regeneration Protocol for Zoysia japonica Based on Callus Cultures

In-Ja Song,Markkandan Ganesan,Eun Jeong Kang,Hyeon-Jin Sun,Tae-Woong Bae,Pyung-Ok Lim,Pill-Soon Song,Hyo-Yeon Lee 한국원예학회 2010 Horticulture, Environment, and Biotechnology Vol.51 No.3

In vitro zoysia grass regeneration has several difficulties. We report here a simple and reproducible protocol by using seed explants. We selected the yellow colored calli for plant regeneration, as other types of calli were found to be poor in their capacity for callus multiplication and/or shoot induction. However, both previous reports and the present study encountered difficulties in plant regeneration with the yellow type calli during their growth and shoot multiplication. Some of the major difficulties included the formation of different types of calli from a single explant that appeared to be of a regenerable type of calli (yellow compact, yellowish white compact and white friable), abnormal growth induction from the callus (hairy root formation, browning, and formation white compact structures resembling somatic embryos), greening of callus without further shoot formation, micro-shoot formation without further growth and conversion of micro-shoots into callus. To circumvent these difficulties, we established an improved protocol for zoysia regeneration. Results showed that 2iP (1.0 ㎎ · ℓ?¹) and GA3 (1.0 ㎎ · ℓ?¹) not only enhanced shoot induction percentage, but also increased the number of shoots from the callus cultures when compared with BAP treatments. During shoot initiation, the difficulties mentioned above were substantially alleviated. Both shoot induction and simultaneous shoot elongation were satisfactorily achieved on the same medium. The elongated shoots were rooted on half MS media. The simple but reproducible regeneration protocol established in this study may facilitate the work on transformation and genetic improvements for Zoysia japonica Steud. and other closely related grass species.

Photo-biotechnology as a tool to improve agronomic traits in crops

Gururani, Mayank Anand,Ganesan, Markkandan,Song, Pill-Soon Elsevier 2015 Biotechnology advances Vol.33 No.1

<P><B>Abstract</B></P> <P>Phytochromes are photosensory phosphoproteins with crucial roles in plant developmental responses to light. Functional studies of individual phytochromes have revealed their distinct roles in the plant's life cycle. Given the importance of phytochromes in key plant developmental processes, genetically manipulating phytochrome expression offers a promising approach to crop improvement. Photo-biotechnology refers to the transgenic expression of phytochrome transgenes or variants of such transgenes. Several studies have indicated that crop cultivars can be improved by modulating the expression of phytochrome genes. The improved traits include enhanced yield, improved grass quality, shade-tolerance, and stress resistance. In this review, we discuss the transgenic expression of phytochrome A and its hyperactive mutant (Ser599Ala-PhyA) in selected crops, such as <I>Zoysia japonica</I> (Japanese lawn grass), <I>Agrostis stolonifera</I> (creeping bentgrass), <I>Oryza sativa</I> (rice), <I>Solanum tuberosum</I> (potato), and <I>Ipomea batatas</I> (sweet potato). The transgenic expression of PhyA and its mutant in various plant species imparts biotechnologically useful traits. Here, we highlight recent advances in the field of photo-biotechnology and review the results of studies in which phytochromes or variants of phytochromes were transgenically expressed in various plant species. We conclude that photo-biotechnology offers an excellent platform for developing crops with improved properties.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phytochromes are photoreceptors that are required for various developmental processes. </LI> <LI> Application of engineered phytochrome genes in various crops is discussed. </LI> <LI> Results with introduction of a mutant PHYA into turfgrasses and other crops are discussed. </LI> <LI> Potential areas for further improvement in photo-biotechnology are highlighted. </LI> </UL> </P>

Ginsenoside Production and Morphological Characterization of Wild Ginseng (Panax ginseng Meyer) Mutant Lines Induced by g-irradiation (^(60)Co) of Adventitious Roots

Jun-Ying Zhang,배태웅,Kyung-Hwan Boo,선현진,송인자,Chi-Hoa Pham,Markkandan Ganesan,양대화,강홍규,Suk-Min Ko,Key-Zung Riu,Pyung-Ok Lim,Hyo-Yeon Lee 고려인삼학회 2011 Journal of Ginseng Research Vol.35 No.3

With the purpose of improving ginsenoside content in adventitious root cultures of Korean wild ginseng (Panax ginseng Meyer),the roots were treated with different dosages of γ-ray (5, 10, 25, 50, 75, 100, and 200 Gy). The growth of adventitious roots was inhibited at over 100 Gy. The irradiated adventitious roots showed significant variation in the morphological parameters and crude saponin content at 50 to100 Gy. Therefore, four mutant cell lines out of the propagation of 35 cell lines treated with 50 Gy and 100Gy were selected on the basis of phenotypic morphology and crude saponin contents relative to the wild type control. The contents of 7 major ginsenosides (Rg_1, Re, Rb_1, Rb_2, Rc, Rf, and Rd) were determined for cell lines 1 and 3 from 100 Gy and lines 2 and 4from 50 Gy treatments. Cell line 2 showed more secondary roots, longer length and superior growth rate than the root controls in flasks and bioreactors. Cell line 1 showed larger average diameter and the growth rate in the bioreactor was comparable with that of the control but greater in the flask cultured roots. Cell lines 1 and 2, especially the former, showed much more ginsenoside contents than the control in flasks and bioreactors. Therefore, we chose cell line 1 for further study of ginsenoside contents. The crude saponin content of line 1 in flask and bioreactor cultures increased by 1.4 and 1.8-fold, respectively, compared to the control. Total contents of 7 ginsenoside types (Rg_1, Re, Rb_1, Rb_2, Rc, Rf, and Rd) increased by 1.8 and 2.3-fold, respectively compared to the control. Crude saponin and ginsenoside contents in the bioreactor culture increased by about 1.4-fold compared to that the flask culture.

Ginsenoside Production and Morphological Characterization of Wild Ginseng (Panax ginseng Meyer) Mutant Lines Induced by γ-irradiation (⁶⁰Co) of Adventitious Roots

Jun-Ying Zhang,Tae-Woong Bae,Kyung-Hwan Boo,Hyeon-Jin Sun,In-Ja Song,Chi-Hoa Pham,Markkandan Ganesan,Dae-Hwa Yang,Hong-Gyu Kang,Suk-Min Ko,Key-Zung Riu,Pyung-Ok Lim,Hyo-Yeon Lee 고려인삼학회 2011 Journal of Ginseng Research Vol.35 No.3

With the purpose of improving ginsenoside content in adventitious root cultures of Korean wild ginseng (Panax ginseng Meyer), the roots were treated with different dosages of γ-ray (5, 10, 25, 50, 75, 100, and 200 Gy). The growth of adventitious roots was inhibited at over 100 Gy. The irradiated adventitious roots showed significant variation in the morphological parameters and crude saponin content at 50 to100 Gy. Therefore, four mutant cell lines out of the propagation of 35 cell lines treated with 50 Gy and 100 Gy were selected on the basis of phenotypic morphology and crude saponin contents relative to the wild type control. The contents of 7 major ginsenosides (Rg₁, Re, Rb₁, Rb₂, Rc, Rf, and Rd) were determined for cell lines 1 and 3 from 100 Gy and lines 2 and 4 from 50 Gy treatments. Cell line 2 showed more secondary roots, longer length and superior growth rate than the root controls in flasks and bioreactors. Cell line 1 showed larger average diameter and the growth rate in the bioreactor was comparable with that of the control but greater in the flask cultured roots. Cell lines 1 and 2, especially the former, showed much more ginsenoside contents than the control in flasks and bioreactors. Therefore, we chose cell line 1 for further study of ginsenoside contents. The crude saponin content of line 1 in flask and bioreactor cultures increased by 1.4 and 1.8-fold, respectively, compared to the control. Total contents of 7 ginsenoside types (Rg₁, Re, Rb₁, Rb₂, Rc, Rf, and Rd) increased by 1.8 and 2.3-fold, respectively compared to the control. Crude saponin and ginsenoside contents in the bioreactor culture increased by about 1.4-fold compared to that the flask culture.

Ginsenoside Production and Morphological Characterization of Wild Ginseng (Panax ginseng Meyer) Mutant Lines Induced by γ-irradiation (⁶⁰Co) of Adventitious Roots

Zhang, Jun-Ying,Bae, Tae-Woong,Boo, Kyung-Hwan,Sun, Hyeon-Jin,Song, In-Ja,Pham, Chi-Hoa,Ganesan, Markkandan,Yang, Dae-Hwa,Kang, Hong-Gyu,Ko, Suk-Min,Riu, Key-Zung,Lim, Pyung-Ok,Lee, Hyo-Yeon The Korean Society of Ginseng 2011 Journal of Ginseng Research Vol.35 No.3

With the purpose of improving ginsenoside content in adventitious root cultures of Korean wild ginseng (Panax ginseng Meyer), the roots were treated with different dosages of ${\gamma}$-ray (5, 10, 25, 50, 75, 100, and 200 Gy). The growth of adventitious roots was inhibited at over 100 Gy. The irradiated adventitious roots showed significant variation in the morphological parameters and crude saponin content at 50 to100 Gy. Therefore, four mutant cell lines out of the propagation of 35 cell lines treated with 50 Gy and 100 Gy were selected on the basis of phenotypic morphology and crude saponin contents relative to the wild type control. The contents of 7 major ginsenosides ($Rg_1$, Re, $Rb_1$, $Rb_2$, Rc, Rf, and Rd) were determined for cell lines 1 and 3 from 100 Gy and lines 2 and 4 from 50 Gy treatments. Cell line 2 showed more secondary roots, longer length and superior growth rate than the root controls in flasks and bioreactors. Cell line 1 showed larger average diameter and the growth rate in the bioreactor was comparable with that of the control but greater in the flask cultured roots. Cell lines 1 and 2, especially the former, showed much more ginsenoside contents than the control in flasks and bioreactors. Therefore, we chose cell line 1 for further study of ginsenoside contents. The crude saponin content of line 1 in flask and bioreactor cultures increased by 1.4 and 1.8-fold, respectively, compared to the control. Total contents of 7 ginsenoside types ($Rg_1$, Re, $Rb_1$, $Rb_2$, Rc, Rf, and Rd) increased by 1.8 and 2.3-fold, respectively compared to the control. Crude saponin and ginsenoside contents in the bioreactor culture increased by about 1.4-fold compared to that the flask culture.