Community water management to intensify agricultural productivity in the polders of the coastal zone of Bangladesh

Paddy and Water Environment - Most of the lands of the southern coastal zone of Bangladesh are protected from tidal flooding and storm surges by embankments constructed during the 1960s and 1970s,...     

A comprehensive study on occurrence records of African neglected and underutilized weed species,Cleome gynandra L. (cat's whiskers) validating the ecogeographical range expansion in West Bengal,India

Cleome gynandra L., commonly known as cat's whiskers, is an erect, branched, annual herb, belonging to the family Cleomaceae. The species is thought to have originated in tropical Africa and Southeast Asia, and thereafter have spread to other tropical and subtropical countries in the Northern and Southern hemispheres. Cat's whiskers is a highly nutritious vegetable and also possesses numerous medicinal values, yet it is considered as a neglected and underutilized weed species (NUS) in most of the world. In India, C. gynandra is recorded in Assam, Gujarat, Kerala, Maharashtra, Rajasthan, Tamil Nadu, and Uttar Pradesh. There is no earlier report of this species in West Bengal, India. This report is the first record of natural occurrence of C. gynandra in West Bengal, India. The main objective of this report is to provide valid information about the invasion and naturalization of this species in a new geographical area supported with suitable data. Global distribution data of cat's whiskers was retrieved from available web resources and mapped using Quantum GIS software in order to validate the de novo nature of occurrence of this species in this region.     

Antibacterial activity of Terminalia pallida

The methanol extract of the dried fruit powder of Terminalia pallida was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.     

Breeding systems and seed production for six weedy taxa of Bidens

Successful reproduction is considered to be the major determining factor for a weedy population to establish, colonize and infest. The breeding systems and seed production of six weedy taxa of Bidens were studied at an experimental garden in Jiangsu province in China. The results from four treatments (open pollination, bagged capitulum, decapitated capitulum, and pollen supplement) indicated that, with the exception of Bidens pilosa var. radiata, all the other five Bidens taxa; namely, B. pilosa var. pilosa, B. pilosa var. minor, B. frondosa, B.bipinnata, and B. biternata, were self‐fertile with a high seed‐set in bagged capitula, and a high autofertility index. Including the trait of vegetative propagation in self‐incompatible B. pilosa var. radiata, all the six weedy taxa of Bidens had the capacity of uniparental reproduction. The pollen limitation values for all six Bidens taxa were low in the present study. However, the seed production of B. pilosa var. radiata is likely to decrease in the absence of sufficient pollinators, related to its high pollen contribution and potential pollen limitation indices. The seed production per plant and per capitulum of the three varieties of B. pilosa was the highest among the six taxa and might contribute to their serious weediness. The breeding system type and seed number per capitulum could be used as a classification reference for Bidens taxa.     

Greenhouse evaluation and inheritance analysis of transgenic cotton expressing <Emphasis Type="Italic">PTM3</Emphasis>, a MADS-box gene of Aspen

The PTM3 (MADS-box) gene characterized from flower of Aspen was ectopically expressed in cotton and was found to result in desirable agronomic traits. Among several transgenic lines, the PTM3 cotton event-10 was found to flower significantly earlier than the control and yield better [Ramachandran et al. (2011)]. We report our findings on performance based on greenhouse evaluation and inheritance of PTM3 cotton event-10. The T₁ progeny of event-10 were grown in pots under RBD design. The progeny were confirmed by kanamycin imbibition test, PCR, and GUS assay which showed the segregation of transgene at about 3:1 ratio. GUS assay was performed with pollen from all transgenic plants; plants that expressed gus in all pollen versus those that showed segregation for expression were found to be at a ratio of 1:2. Similar to observations made in the T₀ generation of event-10, the agronomic evaluation of T₁ progeny exhibited, on an average, earliness of 13 days in flowering, 13.5 days in crop maturity, and 22% of yield enhancement. The T₂ progeny of homozygous lines were grown on field soil in the greenhouse under strip trial design to see the effect as observed from potted plants of T₁ progeny. Inheritance of transgene cassette to T₂ progeny was confirmed by the same tests used to analyze T₁ progeny. As exhibited by T₀ and T₁ progenies, the T₂ progeny also showed earliness of 8 days in flowering, 12 days in crop maturity, and 17% of yield enhancement. The data generated from the progeny over two generations confirms that the PTM3 cotton event-10 is superior in agronomic characters as compared to non-transgenic cotton and is of interest for breeding shorter duration varieties with improved yield.     

Role of exogenous phytohormones on growth and plumbagin accumulation in Plumbago indica hairy roots and conservation of elite root clones via synthetic seeds

The present study describes the role of different exogenous hormones on morphology and plumbagin production in Plumbago indica hairy roots. It was also aimed to conserve elite root clones via synthetic seed technology. Insertion of rolB gene in transformed roots was confirmed by polymerase chain reaction followed by southern blot analysis. Hairy roots were treated with single or in combination of different phytohormones viz. IAA, IBA, 2, 4-D, NAA, BAP, GA₃ and ABA. Cultures incubated with GA₃ (0.5 mg l⁻¹) yielded highest root growth due to formation of profuse lateral branching while NAA (0.5 mg l⁻¹) treatment caused highest plumbagin accumulation. Cultures incubated with 2, 4-D exhibited highest inhibitory effect in terms of both root growth and plumbagin production. All phytohormones were found to be effective at lower concentration. In combinatorial study, GA₃ + NAA (0.5 mg l⁻¹, each) was found optimum for root biomass and plumbagin production at earlier stage of culture. Different combinations of auxins and BAP induced different morphologies ranging from reduction of lateral branching to rapid disorganization of root matrix. The combinations of ABA and selected auxins were not found promising at any of selected concentration. Based on the effect of exogenous hormones on hairy root culture, elite root clones were selected and encapsulated with sodium alginate matrix. Uniform shaped alginate coated synthetic seeds were conserved up to 6 months exhibited high regeneration potential without disturbing plumbagin content.     

Influence of synthetic plant growth substances on the survivorship and developmental parameters of <Emphasis Type="Italic">Spilarctia obliqua</Emphasis> Walker (Lepidoptera: Arctiidae)

The nontarget effects of three plant growth stimulants (gibberellic acid, Siapton and triacontanol) and two plant growth retardants (chlormequat chloride and mepiquat chloride) on the survivorship and developmental parameters of Spilarctia obliqua Walker (Lepidoptera: Arctiidae) were studied. For each compound, various concentrations (0.125×, 0.25×, 0.5×, × , 2× and 4×; × = labeled dose) bracketing the labeled dose were prepared by serial dilution and mixed with an artificial diet for the insect. Gibberellic acid caused an increase in the larval period at × − 4×, but no marked difference was observed in the pupal period or in larval survival at any concentration. Siapton induced a significant increase in larval period at the two highest doses but caused significant reduction in pest survival at × − 4×. Interestingly, triacontanol induced a significant reduction in pest survivorship at almost all doses. The LC₅₀ for triacontanol was 0.206% and LT₅₀ was 266.5 hours at the labeled dose. However, triacontanol did not cause any significant difference in larval or pupal periods at any dose tested. Chlormequat chloride and mepiquat chloride caused significant reduction of larval survivorship at concentrations higher than the labeled doses, and no effect on the larval period. Intriguingly, a significant reduction in pupal period was observed with chlormequat chloride at × and 0.25×. Based on the marked effect of triacontanol on pest survivorship, this study suggests incorporating triacontanol in integrated pest management modules for S. obliqua. Caution in the use of gibberellic acid and Siapton for pest infestations is also indicated.     

Economic analysis of risk of gastrointestinal parasitic infection in cattle in North Eastern States of India

Gastrointestinal parasitic infection is highly prevalent in the North Eastern States (NEH) of India and accounted for significant economic losses across various livestock species. Productivity of cattle in terms of milk yield was estimated to be considerably higher (3,715, 3,590, and 3,154 L) due to strategic anthelmintic treatment as compare to control group (2,928 L). Based on the probability of occurrence of parasitic infection as well as increase in value of milk production, the possible economic gain at state level has been estimated to be Rs. 46 million, Rs. 35 million, and Rs. 14 million, depending upon the different strategic treatment. The government may take up the program to educate the cattle farmers on strategic management against parasitic infecion and simultaneously making available various anthelmintic medicines. This public responsibility of the government to minimize the risk and economic loss due to gastrointestinal parasite infection may reduce the private cost and thereby would increase the social benefits in North Eastern states of India.     

Somatic embryogenesis in Cymbopogon pendulus and evaluation of clonal fidelity of regenerants using ISSR marker

An efficient plant propagation system through somatic embryogenesis was established in Cymbopogon pendulus, an aromatic grass followed by analysis of genetic status of regenerants using ISSR markers. Optimum embryogenic callus induction was observed on MS basal medium supplemented with 13.57 μM 2,4-dicholorophenoxyacetic acid (2,4-D) with 8.88 μM N⁶-benzyladenine (BA). Subsequent culturing of embryogenic calli on MS medium containing 4.52 μM 2,4-D and 8.88–13.32 μM BA gave maximum number of somatic embryos. Addition of coconut water (CW) promoted induction, growth and differentiation of callus and somatic embryogenesis. Further development of embryos into plantlets was achieved on MS medium supplemented with lower concentration of biotin and calcium pantothenate (CaP) along with BA (4.44–13.32 μM) and kinetin (2.32–4.65 μM). The root meristems were established on half strength MS medium containing 2% sucrose and 2.46–9.84 μM Indole3-butyric acid (IBA) and successfully established in soil with 77.8% survival rate in field condition. Thirteen randomly selected regenerated clones were screened using six ISSR primers. Nine clones produced similar monomorphic amplification profiles while remaining clones showed minor variation with absence of certain parental bands and appearance of unique band. Majority of the regenerants maintained genetic fidelity with the generation of few variants as evidenced from similarity matrix estimates using Nei Li's coefficient of similarity data.     

Theaflavins depolymerize microtubule network through tubulin binding and cause apoptosis of cervical carcinoma HeLa cells

Here we studied the antiproliferative activity of theaflavins in cervical carcinoma HeLa cells by investigating their effects on cellular microtubules and purified goat brain tubulin. Theaflavins inhibited proliferation of HeLa cells with IC(50) value of 110 ± 2.1 μg/mL (p = < 0.01), caused cell cycle arrest at G(2)/M phase and induced apoptosis with alteration of expression of pro- and antiapoptotic proteins. Along with these antiproliferative activities, theaflavins act as microtubule depolymerizers. Theaflavins disrupted the microtubule network accompanied by alteration of cellular morphology and also decreased the polymeric tubulin mass of the cells. The polymerization of cold treated depolymerized microtubules in HeLa cells was prevented in the presence of theaflavins. In vitro polymerization of purified tubulin into microtubules was also inhibited by theaflavins with an IC(50) value of 78 ± 2.43 μg/mL (P < 0.01). Thus, disruption of cellular microtubule network of HeLa cells through microtubule depolymerization may be one of the possible mechanisms of antiproliferative activity of theaflavins.