An efficient callus induction and in vitro regeneration were developed using plant growth regulators, carbon sources, and basal media for three selected Malaysian wetland rice varieties (MR220, MR220-CL2, and MR232) and one upland variety (Bario). Effect of plant growth regulator (PGR) was carried out using four different concentrations (1-4 mg/L) of 2,4-D (2, 4-dichlorophenoxyacetic acid), and NAA (1-naphthalene acetic acid) (2.5, 5.0, 7.5, and 10 mg/L) with optimized 2,4-D. Effects of carbon sources (maltose and sorbitol), and basal media (MS, N6, and LS) were also studied with optimized PGR to maximize the induction of regenerable calli. This study found that all four varieties exhibited high frequency of callus induction on MS (Murashige and Skoog) medium that was supplemented with 3 mg/L 2,4-D and 30 g/L maltose. Callus induction frequencies in the cases of MR220, MR220-CL2, MR232, and Bario were found to be 76%, 94%, 85%, and 42% respectively. Morphological analysis through scanning electron microscopy (SEM) and histological analysis revealed the embryogenicity of the induced callus. In the regeneration study, it was observed that combination of 2 mg/L BAP (6-benzylaminopurine), 2 mg/L Kin (Kinetin) and 0.5 mg/L NAA supplemented MS medium has the potential to promote regeneration of selected indica rice varieties with higher regeneration percentage, i.e., 82% (MR220-CL2), 68% (both in MR220 and MR232), and 40% (Bario). The optimized conditions for callus formation and regeneration can be useful for biotechnological practices for the genetic improvement of Malaysian indica rice.

AbstractsThe rapid depletion of fossil fuel reserves and environmental concerns with their combustion necessitate to look for alternative sources for long term sustainability of the world. These concerns also appear serious in developing countries who are striving for rapid economic growth. The net biomass growing potential on the global land surface is 10 times more than the global food, feed, fiber, and energy demands. This study investigates whether the developing countries have sufficient land resource to meet projected energy demand towards 2035 by planting energy crops on surplus agricultural land after food and feed production. The annual yields of four commonly grown energy crops specifically jatropha, switchgrass, miscanthus, and willow have been used to make scenarios and estimate land requirements against each scenario. This paper first performs literature reviews on availability of land resource, past and future trends in land use changes, demand of lands for food production, and potential expansion of croplands. The energy demands towards 2035 are compiled from energy scenarios derived by International Energy Agency (IEA), and British Petroleum (BP). This paper also reviewed bio-physiological characteristics of these energy crops to determine whether they are cultivable under tropical climatic conditions in developing regions. This paper found that projected energy demand through 2035 in developing regions could be provided by energy crops grown on a portion of surplus croplands or upgraded grasslands (27% and 22% respectively for miscanthus scenario). Sustainable land management practices, improved agricultural productivity, and adopting suitable energy crops cultivation can potentially supply increasing energy demands.

The development of efficient tissue culture protocol for somatic embryo would facilitate the genetic modification breeding program. The callus induction and regeneration were studied by using different parameters i.e., auxins, cytokinins, and desiccation treatment. Scanning electron microscopy and histological analysis were performed to identify the embryogenic callus for regeneration. The callus percentage results showed that MS (Murashige and Skoog) basal medium supplemented with 3 mg/L 2, 4-D and 30g/L maltose were the optimal callus induction medium for MR220 (80%) and MR220-CL2 (95%). The morphology of the embryogenic callus was confirmed by the SEM (Scanning Electron Microscopy) (presence of extracellular matrix surface network) and later by histological analysis. Finally, MS media supplemented with 0.5 mg/L NAA (Naphthalene Acetic Acid), 2 mg/L kin, and 1 mg/L BAP were selected as the optimum regeneration media treatment while callus desiccated for 48 h was proved to produce more plantlets in MR220 (60%) and MR220-CL2 (73.33%) compared to control treatment (without desiccation). The protocol presented here showed the necessity for the inclusion of partial desiccation as an important step in the tissue culture protocol of Malaysian indica rice genotypes in order to enhance their regeneration potential.

The development of an efficient tissue culture protocol for somatic embryo would facilitate the genetic modification in breeding program. The present study describes the reproducible protocols for three wetland Malaysian rice cultivars (MR232, MR220 and MR220-CL2) and upland rice (Bario) via somatic embryogenesis. In the present study, four preheat treatments (35, 40, 45 and 50°C) were applied to mature seeds with different imbibition periods (3, 5 and 7 days) prior to culture on MS media with 3 mg/L 2,4-D. The results showed that the cultivars exhibited the highest callus induction percentage from 45°C pre-heated seeds and 3 days imbibition (100%, 96%, 100% and 95% for MR232, MR220, MR220-CL2 and Bario, respectively). Callus was induced early ranging from 3 to 12 days compared to without pre-heat treatment. The regeneration efficiency for MR220 and MR220-CL2 cultivars was significantly higher compared to the control treatment. However, both 45°C and 25°C (control) treatments produced higher plantlet regeneration for MR232 and Bario. This study observed that pre-heat treated seeds prior to callus induction did promote callusing and hence regeneration. These findings can be used to establish a suitable protocol for the in vitro regeneration system for several genetic improvements in the numerous stress tolerances of Malaysian rice.

Labisia pumila is a precious herb in Southeast Asia that is traditionally used as a health supplement and has been extensively commercialized due to its claimed therapeutic properties in boosting a healthy female reproductive system. Indigenous people used these plants by boiling the leaves; however, in recent years it has been marketed as powdered or capsuled products. Accordingly, accuracy in determination of the authenticity of these modern herbal products has faced great challenges. Lack of authenticity is a public health risk because incorrectly used herbal species can cause adverse effects. Hence, any measures that may aid product authentication would be beneficial. Given the widespread use of Labisia herbal products, the current study focuses on authenticity testing via an integral approach of DNA barcoding and qualitative analysis using HPLC. This study successfully generated DNA reference barcodes (ITS2 and rbcL) for L.pumila var. alata and pumila. The DNA barcode that was generated was then used to identify species of Labisia pumila in herbal medicinal products, while HPLC was utilized to determine their quality. The findings through the synergistic approach (DNA barcode and HPLC) implemented in this study indicate the importance of both methods in providing the strong evidence required for the identification of true species and to examine the authenticity of such herbal medicinal products.