Agro-biodiversity and ethnobotany of Lakshadweep Islands of India

The Lakshadweep is a tiny landmass of 32 km² area (8^o–12^oN, 71^o–74^oE) constituted by a group of 27 small atolls located in the Indian territory of Arabian Sea of Indian Ocean. Studies on crop genetic diversity including wild relatives of crop plants of the region are little known except for coconut palm. This report deals with 106 collections assembled in two exploration and collection missions comprising 46 plant species under 35 genera belonging to 24 families. The plant germplasm collected during the trips are mostly useful as vegetable, fibre, medicinal plant, dye, edible tuber, timber and ecosystem service provider. The crop wild relatives collected during the study include that of sunnhemp, melon, yam, jute, pigeon pea, sugarcane, etc. A set of germplasm accessions was sent to national research institutes for regeneration. Out of the total collection, 64 accessions were assigned with national identity (Indigenous Collection or IC numbers: IC 0572014 to IC 0572077), and conserved in long term storage at National Gene Bank or in the field gene bank of ICAR-NBPGR, New Delhi. The important germplasm assembled from the islands include highly pungent betel leaf and a large fruited noni. Plants of Cajanus scarabaeoides (L.) Thouars, bitter less Cucumis melo L. var. agrestis Naudin saline tolerant Canavalia cathartica Thouars, Vigna marina (Burm.) Merr. and Corchorus trilocularis L. were the unique wild relatives collected. The current report is the first of its kind on the exploration and collection of plant genetic resources (other than coconut) from Lakshadweep Islands. Wild melon accessions collected are currently employed in distant hybridization programs. During the survey, ethnobotanic information of 23 plants for medicinal and other uses was also documented. Novel uses of the native plant species in the islands indicate their potential for exploitation in other coastal ecosystems. This report aims to highlight the potential plant resources of the region for direct human use and in future breeding programs.     

Preclinical evaluation of anticancer efficacy and pharmacological properties of FBA-TPQ, a novel synthetic makaluvamine analog

We have recently designed and synthesized a novel iminoquinone anticancer agent, 7-(4-fluorobenzylamino)-1,3,4,8-tetrahydropyrrolo[4,3,2-de]quinolin-8(1H)-one (FBA-TPQ) and initiated its preclinical development. Herein we investigated its efficacy, safety, and pharmacokinetics in in vitro and in vivo models of human pancreatic cancer. Our results demonstrated that FBA-TPQ inhibited pancreatic cancer cell growth, induced apoptosis, and caused cell cycle arrest in vitro. It inhibited the growth of xenograft tumors with minimal host toxicity. To facilitate future preclinical and clinical development of the agent, we also developed and validated a Rapid Resolution Liquid Chromatography (RRLC) method for quantitative analysis of FBA-TPQ in plasma and tissue samples. The method was found to be precise, accurate, and specific. Using this method, we carried out in vitro and in vivo evaluations of the pharmacological properties of FBA-TPQ, including stability in plasma, plasma protein binding, metabolism by S9 enzymes, plasma pharmacokinetics, and tissue distribution. Our results indicate that FBA-TPQ is a potential therapeutic agent for pancreatic cancer, providing a basis for future preclinical and clinical development.     

Induction of polyploids in acid lime (Citrus aurantifolia) through colchicine treatment of in vitro derived shoot tip explants

Polyploid breeding is an effective tool to induce variability in the existing population, specifically in the crops having very narrow genetic base such as acid lime. Hence, an experiment was conducted to induce polyploidy in acid lime through colchicine treatment. Higher frequency of triploids were obtained in 250 μM colchicine treatment (27.27%), whereas combination of 3× (21.42%), 4× (13.33%) and aneuploid (6.67%) were induced at 500 μM colchicine treatment. Measurement of stomatal density and guard cell size of colchiploids revealed that the former one has negative relation with ploidy level and a positive relation was observed between guard cell size and ploidy level. Further, area and size of nuclei also had a positive relation with ploidy level. Hence, stomatal density, guard cell and nuclei size can be used effectively as morphological marker for preliminary polyploid screening. From the experiment, it can be concluded that 500 μM colchicine treatment of in vitro derived shoot tip explants of acid lime is optimum for creating maximum possible variability through polyploidization in the existing acid lime population.     

RNAi as a management tool for the western corn rootworm,Diabrotica virgifera virgifera

The western corn rootworm (WCR), Diabrotica virgifera virgifera, is the most important pest of corn in the US Corn Belt. Economic estimates indicate that costs of control and yield loss associated with WCR damage exceed $US 1 billion annually. Historically, corn rootworm management has been extremely difficult because of its ability to evolve resistance to both chemical insecticides and cultural control practices. Since 2003, the only novel commercialized developments in rootworm management have been transgenic plants expressing Bt insecticidal proteins. Four transgenic insecticidal proteins are currently registered for rootworm management, and field resistance to proteins from the Cry3 family highlights the importance of developing traits with new modes of action. One of the newest approaches for controlling rootworm pests involves RNA interference (RNAi). This review describes the current understanding of the RNAi mechanisms in WCR and the use of this technology for WCR management. Further, the review addresses ecological risk assessment of RNAi and insect resistance management of RNAi for corn rootworm. © 2016 Society of Chemical Industry     

Effects of calorie restriction on the expression of manganese superoxide dismutase and catalase under oxidative stress conditions in the rotifer <Emphasis Type="Italic">Brachionus plicatilis</Emphasis>

Calorie restriction (CR) in the rotifer Brachionus plicatilis extends its lifespan, as it enhances the expression of antioxidant enzymes such as manganese superoxide dismutase (Mn SOD) and catalase. Here we show that CR also increased the mRNA levels of these antioxidant enzymes upon exposure to oxidative stress. Rotifers cultured under CR showed a higher survival rate than those fed ad libitum (AL) upon exposure to 0.05–0.2 μM juglone, an oxidative stress inducer. The relative mRNA levels of Mn SOD and catalase before exposure to juglone were slightly higher in the CR rotifers than in their AL counterparts, although these differences were not statistically significant. AL rotifers showed no apparent upregulation of the mRNA levels of these antioxidant enzymes upon exposure to 0.025 and 0.05 μM juglone. In contrast, the CR rotifers increased the mRNA levels of Mn SOD and catalase by up to 5.4-fold and 4.2-fold, respectively, resulting in significant differences between their levels in AL and CR rotifers under oxidative stress conditions. Furthermore, the protein level of catalase was clearly higher in CR than in AL rotifers 6 h after exposure to oxidative stress. These results suggest that the upregulation of Mn SOD and catalase genes is involved in CR-induced resistance to oxidative stress in the rotifer.     

Feasibility of cultivation of Kappaphycus alvarezii (Doty) Doty at different localities on the Northwest coast of India

Kappaphycus alvarezii was cultivated at three places, viz. Mithapur, Okha and Beyt Dwarka on the Northwest coast of India. The biomass and growth rates were measured at 15-day intervals up to 45 days and varied differently for different growth periods at these places. Thus, at 15, 30 and 45 days, the biomass (fresh wt) varied from 182.0±19.96 to 435.0±23.66 g, from 366.0±118.09 to 1096.0±61.43 g and from 530.5±50.95 to 1537.0±43.54 g, respectively, with respective daily growth rates (%) from 3.95±0.78 to 9.80±0.63, from 3.64±0.01 to 13.98±3.07 and from 3.69±0.23 to 6.07±0.06. The seawater temperature, salinity, nitrate and phosphate ranged from 19.3 to 26.9 °C, from 30.81 to 36.83‰, from 11.60 to 19.75 μmol L⁻¹ and from 2.37 to 5.0 μmol L⁻¹ respectively. The growth rate between the culture months was significantly different at Okha at P <0.01. Further, it was significantly correlated to salinity at Mithapur while at Okha and Beyt Dwarka, the same was significantly correlated to nitrate and seawater temperature. Based on this study, commercial cultivation at these localities is quite feasible.     

Current Status and Perspective on the Use of Viral-Based Vectors in Eukaryotic Microalgae

During the last two decades, microalgae have attracted increasing interest, both commercially and scientifically. Commercial potential involves utilizing valuable natural compounds, including carotenoids, polysaccharides, and polyunsaturated fatty acids, which are widely applicable in food, biofuel, and pharmaceutical industries. Conversely, scientific potential focuses on bioreactors for producing recombinant proteins and developing viable technologies to significantly increase the yield and harvest periods. Here, viral-based vectors and transient expression strategies have significantly contributed to improving plant biotechnology. We present an updated outlook covering microalgal biotechnology for pharmaceutical application, transformation techniques for generating recombinant proteins, and genetic engineering tactics for viral-based vector construction. Challenges in industrial application are also discussed.     

Dry matter accumulation and nutrient uptake patterns of onion seed crop

Abstract

Dry matter accumulation and nutrient uptake patterns of crops must be determined to optimize fertilizer scheduling. This study assesses the dry matter accumulation and nutrient uptake patterns of onion seed crop. Plant samples were collected between 0 and 120?days after planting, and their nutrient content was analyzed to determine the dry matter accumulation and nutrient uptake patterns. The quantity and period of nutrient uptake and the mobility of nutrients within the plant parts varied for different nutrients. The absorption of nitrogen (N) and potassium (K) was the highest during vegetative stage, whereas phosphorus (P) and sulfur (S) uptake was the highest during flower initiation stage. N, P, K, and S, which had accumulated in the vegetative parts, moved from the senesced vegetative parts to the inflorescence during the reproductive stages owing to their high mobility in the phloem. The onion plants continued to absorb zinc, copper, manganese, and iron throughout their growth owing to the immobility of these elements in plant system. The result of this study may facilitate efficient scheduling of fertilizer application to increase nutrient uptake and yield.