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In order to create accurate control techniques against insect pests, correct taxonomic identification is critical. This paper describes the molecular phylogeny of Grey weevil, Myllocerus viridanus (Fabricius) by the sequencing of their mitochondrial cytochrome B gene. The development of a simple and most elegant tools of DNA barcoding has made taxonomy and phylogeny studies a much facile process. M. viridanus is among the important polyphagous pests of plants of agricultural and horticultural importance. The sequencing of Cyt B gene yielded a 273 bp nucleotide product. Phylogentic analysis was carried out in Mega 11 software. Gen Bank deposition indicated the novel and first time records of cytochromeb gene barcode of M. viridanus and first time deposit of a species from the genus Myllocerus. The deposit was provided with an accession number OM223090. Further analysis showed that the partial sequence of mitochondrial cytochrome B of M.viridanus has 88.89% similarity with that of Romualdius bifoveolatus (KX087356) .The identity of M.viridanus(OM223090)ranged from 88.17 to 83.68% when nucleotide BLAST was carried out with nearest 21 species of curculionids (NCBI). The result indicated that cytochrome b gene barcoding can be successfully used to resolve species level identification of the members of the family Curculionidae and the genus Myllocerus of the order Coleoptera. Thus mitochondrial Cytochrome b gene like mitochondrial COX 1 gene, can be used as an efficient tool for the species level identification of the members of Coleopterans. Further interpretation on phylogeny was done by constructing neighbor joining tree using Kimura -2 Parameter. This approach was very informative and it helped in the better understanding of genetic variation among closely related species of Curculionids.

Background Cocoa, being a shade loving crop cannot withstand long periods of water stress. Breeding for drought tolerance is the need of the hour due to change in climatic condition and extension of crop to non-traditional areas. Hybrids were produced by crossing four tolerant genotypes in all possible combination. The cross GV1 55 x M 13.12 didn’t yield any fruit due to cross incompatibility between these genotypes. Various biochemical parameters act as the true indicators to select tolerant and susceptible types. The major biochemical parameters considered after imposing stress included proline, nitrate reductase activity, superoxide dismutase content and glycine betaine. Results The drought tolerant hybrids were having high amount of proline, superoxide dismutase enzyme and glycine betaine content. Normally, plants having drought stress show low amount of nitrate reductase activity. However, in case of hybrids, the drought tolerant hybrids were having higher NR activity than the susceptible hybrids. The highest amount of NR was found in the control plants kept at fully irrigated conditions. Conclusions This experiment showed the role of different biochemical enzymes and osmolytes in giving tolerance to plants during drought stress. Logistic regression analysis selected proline and nitrate reductase as the two biochemical markers for identifying efficient drought tolerant genotypes in the future breeding programmes.

Background: Cowpea is a major pulse crop in India. Developing cowpea cultivars with high yield and sustainable protein content contributes to food and nutritional security. Hybridization followed by careful selection of genotypes from the early segregating populations may produce a final cultivar with high yield coupled with high protein content. Methods: The genetic material used in the present investigation were derived from crosses of three cultivars i.e., H10 (Anaswara x PKB 3) and H11 (Anaswara x PKB 4). The crosses were evaluated in the Department of Plant Breeding and Genetics, Kerala Agricultural University, Thrissur during cowpea season 2015-2017. Trait association based on correlation and path analysis was carried out with phenotypic data from F2 and F3 generations of the crosses. Result: In F2 generation of cross H10, number of pods per plant and number of seeds per pod displayed significant positive correlation with seed yield per plant. In F3 generation of cross H10, number of pods per plant and 100-seed weight per plant exhibited significant positive correlation with seed yield per plant. In cross H11, number of pods, pod length, single pod weight, number of seeds per pod and 100-seed weight revealed significant1 positive correlation with yield in segregating generations. On path analysis, various quantitative characters showed positive direct effects on seed yield. Selection of segregants based on the yield contributing characters is likely to be desirable for yield improvement in cowpea.

The paper describes the evolutionary lineage of the grey weevil Myllocerus undatus Marshall and Myllocerus viridanus (Fabricius)(Coleoptera:Curculionidae) using their partial mitochondrial cytochrome oxidase I gene sequencing. The study revealed that the species discrimination becomes much easier by the process of DNA barcoding.The partial sequencing of cytochrome oxidase I gene of M.undatus revealed 657–658 bp sequences The GenBank deposition indicated the novel and first-time records of M.undatus and was provided with accession numbers KU871374, MG021104, MG021105 and MG407181. The nucleotide sequences with each accession number showed 99% identity with each other whereas the protein product showed 100% identity. The protein product of M.undatus (MG021104) shows 100%identity to Myllocerus undecimpustulatus (KP851146) reported from Ludhiana, Punjab. Partial sequencing of mitochondrial COI gene of M.viridanus yielded a 630 bp product by PCR amplification. Protein blast of mitochondrial partial CO1 sequence of M.undatus and M.viridanus showed 98.57% identity with 3 amino acid substitutions. N-J tree of both the species was constructed and evolutionary analyses were done in MEGA7.

Purpose. Staphylococcus aureus causes a wide range of infections, such as endocarditis, pneumonia, osteomyelitis, skin and soft tissue infections, and implant/in-dwelling device-related infections. S. aureus poses a significant challenge to clinicians because of its ability to rapidly acquire multi-drug resistance and quickly progress into a recurrent, chronic infection by biofilm formation. Levonadifloxacin (WCK 771) is a novel broad-spectrum antibacterial agent (it recently completed a phase 3 trial in India) with a differentiated mechanism of action involving high affinity to staphylococcal DNA gyrase, and is active against multi-drug-resistant (MDR) S. aureus , including those that are resistant to quinolones. The present study investigated the bactericidal activity of levonadifloxacin against biofilm-embedded S. aureus clinical isolates in comparison with other anti- S. aureus drugs. Methodology. The bactericidal activity of levonadifloxacin and comparator drugs such as vancomycin, linezolid and daptomycin was evaluated against planktonic and biofilm-encapsulated recent methicillin- and quinolone-resistant S. aureus clinical isolates using time–kill, biofilm eradication and scanning electron microscopy analysis. Results. Levonadifloxacin displayed a consistent ≥90 % bacterial kill rate against biofilm-embedded organisms, while vancomycin and linezolid displayed variable activity and daptomycin did not show any activity. Scanning electron microscopy images further confirmed the efficacy of levonadifloxacin against biofilm, showing the disruption of biofilm structure and a corresponding reduction in the viable bacterial count. Conclusion. These results show that levonadifloxacin has an improved bactericidal effect on biofilm-embedded quinolone-resistant S. aureus and meticillin-resistant S. aureus , and that it can be a promising treatment option for such infections.

Pyrenacantha volubilis Wight. is a dioecious liana occurring in small, clustered populations. The species had no documented use until the recent past, when it was identified to be a source of a highly traded anti-cancer drug – camptothecin. In the present study, we examine the genetic diversity of 12 fragmented natural populations of P. volubilis using morphological and molecular traits. Twelve polymorphic Inter Simple Sequence Repeat (ISSR) primers and 29 agromorphological traits were used to discriminate the populations using UPGMA and NJ tree algorithms respectively. The ISSR amplicon profile had 133 distinct bands. The maximum number of amplicons were produced by UBC 844 (20 bands) and the average polymorphism was 80.07 per cent. The dendrograms obtained based on molecular and agro-morphological data are in close congruence. The Thiruvananthapuram population stood apart in both the analyses as a discrete outgroup: perhaps a consequence of local adaptation. Substantial genetic diversity exists among populations. This could be tapped in domestication, which is the only way forward for the long-term survival of this species. We also report for the first time a standardized method for extraction of genomic DNA from the leaves of P. volubilis.

The aromatic rice cultivars possess excellent aroma generally when grown in their favourable and specific environments. An early maturing selection from a Kerala aromatic local landrace with short grains, named ‘Biriyanicheera’, when grown in normal tropical conditions was sufficiently fragrant. The present study focused on the analysis of aroma in ‘Biriyanicheera’ rice genotype through molecular methods. The seeds of two aromatic rice varieties viz., Biriyanicheera and Gandhakasala (from Palakkad, Thrissur and Ernakulam districts) along with one non-aromatic rice variety Triveni (control) were used for the study. The BADH2 gene was amplified in all the three rice varieties. Upon sequencing the amplified PCR products of genomic DNA, the mutation in BADH2 gene was detected. The sequencing results of aromatic varieties revealed the presence of 8 base pair mutation in exon 7 in Biriyanicheera and Gandhakasala, whereas this mutation was absent in the non-aromatic variety Triveni. This indicated that aroma production in Biriyanicheera variety is due to similar mutation in BADH2 gene as that of the popular scented rice Basmati.

The aromatic rice cultivars sometimes show variation in aroma when they are grown in regions other than their normal traditional growing regions. An early maturing selection from a Kerala aromatic local landrace with short grains, named 'Biriyanicheera', when grown in normal tropical conditions was sufficiently fragrant. The present study focused on the analysis of aroma in 'Biriyanicheera' rice genotype through molecular methods.The seeds of two aromatic rice varieties viz., Biriyanicheera and Gandhakasala (aromatic check) along with one non-aromatic rice variety Triveni (control) were used for the study. The BADH2 gene was amplified in all the three rice varieties. Upon sequencing the amplified PCR products of genomic DNA, the mutation in BADH2 gene was detected. The sequencing results of aromatic rice varieties revealed the presence of 8 base pair mutation in exon 7 in Biriyanicheera and Gandhakasaala, whereas this mutation was absent in the non-aromatic variety Triveni.Aroma production in Biriyanicheera variety is observed to be due to the similar mutation in BADH2 gene as that of the popular scented rice Basmati.

Background: Blackgram is generally considered as a shade sensitive crop. Nevertheless, it fits well in intercropping, crop rotation and crop mixture in coconut gardens thus forming an integral part of cropping systems of the tropics. To encourage and extend blackgram cultivation in coconut gardens, suitable varieties tolerant to shade, need to be identified. The current study aims to screen shade tolerant blackgram varieties with respect to morpho-physiological characters and yield. Methods: Field experiment was conducted during Rabi 2019 at College of Agriculture, Vellayani, Kerala, India. Uniformly spaced coconut palms of age above 40 years were selected having a light intensity of 40-46.5 Klux. Twelve promising blackgram varieties along with three cultures were evaluated under low light intensity in coconut garden. Morpho-physiological attributes and yields were recorded and analysed statistically. Result: Superior growth attributes and physiological parameters like stomatal frequency, chlorophyll content, photosynthetic rate and transpiration rate were recorded in varieties namely, DBGV 5, Sumanjana and VBN 5. These varieties were found tolerant to low light intensity with DBGV 5 recording significantly higher yield (1183.33 kg ha-1) followed by VBN 5 (916.67 kg ha-1) and Sumanjana (906.67 kg ha-1) and could be recommended as suitable for intercropping in coconut garden.

Moisture stress is one of the major impediments in establishment of plantations since the seedlings are susceptible to moisture stress. Rapid recovery from the drought stress is as important as stress tolerance of tree seedlings. Present study evaluated the physiological and biochemical responses related with stress tolerance and recovery in plus trees of teak from different provenances. One-and-a-half-year-old ramets of eleven plus trees of teak from different provenance of Kerala were exposed to two consecutive drought treatments, till most of leaves exhibited symptoms of wilting with an intervening period of stress relief through rehydration for six days in green house nursery. During the second cycle of drought stress and recovery, physiological parameters like relative water content, canopy air temperature, photosynthesis, stomatal conductance, transpiration, chlorophyll content, chlorophyll stability index and cell membrane stability index were determined. The biochemical constituents like total soluble protein, nitrate reductase, free amino acid, proline, glycine betaine, soluble sugar, super oxide dismutase, peroxidase and malondialdehyde were also recorded in addition to leaf numbers before and after stress. The results showed that physiological and biochemical parameters are crucial to maintain seedling functions during drought and to rapidly recover after re-watering during early vegetative stage. During stress and after rehydration, accessions exhibited variation between full and partial recovery in which both genetic and epigenetic factors may play crucial role. Combinations of photo-protection, osmoregulants and antioxidants measures are employed by teak to combat drought stress. Our results also suggest considerable variation that both drought stress and recovery among the plus trees that were originally selected for growth and wood quality and the potential to use them for further breeding.

The present investigation was conducted to evaluate the variability created due to induction of in vitro mutagenesis in cassava. The calli and somatic embryos from the leaf explants of superior cassava genotypes Sree Jaya and CC1 established in Murashigue and Schoog (MS) media supplemented with 8 mg L -1 picloram were subjected to treatment with Ethyl Methyl Sulphonate (EMS), 0.6-1.2 per cent at 0.1 per cent interval. Forty-four plants survived out of sixty-eight regenerated plants kept for hardening under pad and fan greenhouse followed by rain shelter. Irrespective of the dosage field evaluation of these plants showed variations in morphological traits with respect to their respective controls at 3, 6 and 9 months after planting (MAP). These plants can be clonally propagated and the genetics of the observed variations in quantitative traits of these plants can be validated under different conditions.

Fourteen blackgram genotypes (comprising 10 advanced generations and four parents) were evaluated for three different season viz., Kharif, Rabi and summer both in open conditions as well as inter crop in coconut garden under six environments. Analysis of variance on the data pooled over seasons showed significant difference between genotypes for days to flowering, number of pod bearing branches, number of pods, length of pods, 100-seed weight and yield per plant. Environmental effect was significant for all the traits except plant height whereas genotype x environmental interaction were significant for all the traits. Analysis of genotype x environment interaction by AMMI model showed blackgram culture T6 (4.5.9; T9 x Rusami) as the best with respect to days to flowering, number of branches per plant, pod bearing branches per plant and number of pods per plant for all environments. The genotype T5 (4.5.8; T9 x Rusami) with high mean yield and stability can be selected for cultivation under all environments.

Bitter gourd (Momordica charantia) is one of the world’s major vegetable crops, which belongs to the family Cucurbitaceae. The genus Momordica is a native of the Paleotropics and comprises about 60 species. Bitter gourd grows in tropical and subtropical areas, including parts of East Africa, Asia, the Caribbean, and South America, where it is used not only as a food but also as a medicine. Two botanical varieties viz., var. charantia synonymous with large-fruited cultivated Chinese bitter melon and var. muricata representing small-fruited, predominantly wild forms were recognized. Wide variability was noticed especially among cultivated types for fruit and seed morphology. The plant is monoecious, annual climber with long-stalked leaves and yellow, solitary male and female flowers borne on the leaf axils. The warty and oblong or elliptical-shaped fruit is botanically a ‘pepo.’ The plant grows well in a variety of soils and begins flowering about one month after planting. It is used as a food, bitter flavoring, and medicine. Bitter gourd has a relatively high nutritional value due to high iron and ascorbic acid content. Indians have traditionally used the leaves and fruits as a medicine to treat diabetes, colic, and to heal skin sores and wounds. Bitter gourd is reported to possess antioxidant, antimicrobial, antiviral, and antidiabetic properties.

Sepsis is a life-threatening systemic inflammatory condition triggered as a result of an excessive host immune response to infection. In the past, immunomodulators have demonstrated a protective effect in sepsis. Azithromycin (a macrolide antibiotic) has immunomodulatory activity and was therefore evaluated in combination with ceftriaxone in a clinically relevant murine model of sepsis induced by cecal ligation and puncture (CLP). First, mice underwent CLP and 3 h later were administered the vehicle or a subprotective dose of ceftriaxone (100 mg/kg of body weight subcutaneously) alone or in combination with an immunomodulatory dose of azithromycin (100 mg/kg intraperitoneally). Survival was monitored for 5 days. In order to assess the immunomodulatory activity, parameters such as plasma and lung cytokine (interleukin-6 [IL-6], IL-1β, tumor necrosis factor alpha) concentrations, the plasma glutathione (GSH) concentration, plasma and lung myeloperoxidase (MPO) concentrations, body temperature, blood glucose concentration, and total white blood cell count, along with the bacterial load in blood, peritoneal lavage fluid, and lung homogenate, were measured 18 h after CLP challenge. Azithromycin in the presence of ceftriaxone significantly improved the survival of CLP-challenged mice. Further, the combination attenuated the elevated levels of inflammatory cytokines and MPO in plasma and lung tissue and increased the body temperature and blood glucose and GSH concentrations, which were otherwise markedly decreased in CLP-challenged mice. Ceftriaxone produced a significant reduction in the bacterial load, while coadministration of azithromycin did not produce a further reduction. Therefore, the survival benefit offered by azithromycin was due to immunomodulation and not its antibacterial action. The findings of this study indicate that azithromycin, in conjunction with appropriate antibacterial agents, could provide clinical benefits in sepsis.

Thirteen early maturing cassava genotypes were evaluated along with M4, a high yielding variety at College of Horticulture, Kerala Agricultural University, Thrissur, India. All the fourteen genotypes differed with respect to quantitative and qualitative trait. Variability was more for aerial parts. Genotypes showed variable response to cassava mosaic disease (CMD) and cassava leaf spot. Three genotypes were resistant to CMD. Tuber yield had strong correlation with stem girth, tuber length, biomass and dry matter. Plant height, branch height and stem girth exhibited high heritability. Based on the biometric traits, genotypes could be grouped in to five clusters. High yielding varieties and local accessions fall in to the same cluster indicating the superiority of local accessions. Ranking of the accessions was done by construction of selection index indicated that CSV COH 1 a local accession collected from Malappuram district was the best followed by Sree Jaya a high yielding variety.

Surveys were conducted twice in the major rice tracts of Palakkad, once during January-February, and the other during August-September in 2016. Three major Echinochloa types were identified infesting rice fields, causing severe crop competition. The three types were E. colona, with awnless spikelets and two types of E. crus-galli, viz.E. crus-galli (type A) having short awns and E. crusgalli (type B) having long awns. Other than the length and arrangement of awns, there were no significant differences in the morphological characters of the latter two types. Frequency and relative frequency was the highest for E. crus-galli (type B). There was no specific association between the Echinochloa types and soil nutrient parameters, probably as there were no drastic differences in the chemical properties among the different locations. Cluster analysis classified Echinochloa types in to 5 groups at 66.67% similarity level. The study concludes that in a less productive environment, the awned types of Echinochloa could have a better chance of survival.