Physical and hydraulic properties of baked ceramic aggregates used for plant growth medium.

Baked ceramic aggregates (fritted clay, arcillite) have been used for plant research both on the ground and in microgravity. Optimal control of water and air within the root zone in any gravity environment depends on physical and hydraulic properties of the aggregate, which were evaluated for 0.25-1-mm and 1-2-mm particle size distributions. The maximum bulk densities obtained by any packing technique were 0.68 and 0.64 g cm-3 for 0.25-1-mm and 1-2-mm particles, respectively. Wettable porosity obtained by infiltration with water was approximately 65%, substantially lower than total porosity of approximately 74%. Aggregate of both particle sizes exhibited a bimodal pore size distribution consisting of inter-aggregate macropores and intra-aggregate micropores, with the transition from macro- to microporosity beginning at volumetric water content of approximately 36% to 39%. For inter-aggregate water contents that support optimal plant growth there is 45% change in water content that occurs over a relatively small matric suction range of 0-20 cm H2O for 0.25-1-mm and 0 to -10 cm H2O for 1-2-mm aggregate. Hysteresis is substantial between draining and wetting aggregate, which results in as much as a approximately 10% to 20% difference in volumetric water content for a given matric potential. Hydraulic conductivity was approximately an order of magnitude higher for 1-2-mm than for 0.25-1-mm aggregate until significant drainage of the inter-aggregate pore space occurred. The large change in water content for a relatively small change in matric potential suggests that significant differences in water retention may be observed in microgravity as compared to earth.     

Inhibitory activity of homoisoflavonoids from Caesalpinia sappan against Beauveria bassiana

Four homoisoflavonoids, 4-O-methylsappanol (1), protosappanin A (2), brazilin (3) and caeasalpin J (4), isolated from Caesalpinia sappan, were tested for inhibitory activity against Beauveria bassiana. Compound 1 showed activity against this fungus.     

Detection of OvHV-2 from an outbreak of sheep associated malignant catarrhal fever from crossbred cattle of Southern India

An outbreak of sheep associated malignant catarrhal fever in crossbred cattle in a village of Andhra Pradesh, southern India, affected thirteen adult cows and two calves from a population of forty animals. All the affected animals were died between December and January 2013–14. The clinical and gross postmortem findings were typical of MCF in Indian crossbred cattle. Migrating sheep flocks were suspected source of infection for the cattle. The diagnosis was confirmed by heminested PCR in all the affected cattle and the suspected sheep flock. The PCR provided evidence of ovine herpes virus type 2.     

A short review on sugarcane: its domestication,molecular manipulations and future perspectives

Sugarcane (Saccharum spp.) is a special crop plant that underwent anthropogenic evolution from a wild grass species to an important food, fodder, and energy crop. Unlike any other grass species which were selected for their kernels, sugarcane was selected for its high stem sucrose accumulation. Flowering in sugarcane is not favored since flowering diverts the stored sugar resources for the reproductive and developmental energy needs. Cultivars are vegetatively propagated and sugarcane breeding is still essentially focused on conventional methods, since the knowledge of sugarcane genetics has lagged that of other major crops. Cultivar improvement has been extremely challenging due to its polyploidy and aneuploidy nature derived from a few interspecific hybridizations between Saccharum officinarum and Saccharum spontaneum, revealing the coexistence of two distinct genome organization modes in the modern variety. Alongside implementation of modern agricultural techniques, generation of hybrid clones, transgenics and genome edited events will help to meet the ever-growing bioenergy needs. Additionally, there are two common biotechnological approaches to improve plant stress tolerance, which includes marker-assisted selection (MAS) and genetic transformation. During the past two decades, the use of molecular approaches has contributed greatly to a better understanding of the genetic and biochemical basis of plant stress-tolerance and in some cases, it led to the development of plants with enhanced tolerance to abiotic stress. Hence, this review mainly intends on the events that shaped the sugarcane as what it is now and what challenges ahead and measures taken to further improve its yield, production and maximize utilization to beat the growing demands.

     

Lhx2 selector activity specifies cortical identity and suppresses hippocampal organizer fate

The earliest step in creating the cerebral cortex is the specification of neuroepithelium to a cortical fate. Using mouse genetic mosaics and timed inactivations, we demonstrated that Lhx2 acts as a classic selector gene and essential intrinsic determinant of cortical identity. Lhx2 selector activity is restricted to an early critical period when stem cells comprise the cortical neuroepithelium, where it acts cell-autonomously to specify cortical identity and suppress alternative fates in a spatially dependent manner. Laterally, Lhx2 null cells adopt antihem identity, whereas medially they become cortical hem cells, which can induce and organize ectopic hippocampal fields. In addition to providing functional evidence for Lhx2 selector activity, these findings show that the cortical hem is a hippocampal organizer.     

Identification and characterization of EST-SSRs in finger millet (<Emphasis Type="Italic">Eleusine coracana</Emphasis> (L.) Gaertn.)

In recent years, microsatellites have become the most used markers for studying population genetic diversity. The increased availability of the DNA sequences has given the possibility to develop EST-derived SSR markers. A total of 1,927 ESTs of Eleusine coracana available in the NCBI database were mined for SSRs. Di-nucleotides are the most occurring motifs accounting for more than 50% of the repeats, of which GA was the most abundant motif and tetra-nucleotides are the least occurring motifs. Of the 132 markers identified, 30 primer pairs based were synthesized. SSR markers were used for variety discrimination and genetic assessment in 15 finger millet accessions; 20 primers showed polymorphism and 13 primers were identified as having a PIC value above 0.5. On the basis of the distribution of these polymorphic alleles, the 15 accessions were classified into two groups. This study has demonstrated the potential of EST-derived SSR primer pairs in finger millet. These primers will serve as valuable source for further breeding programs.     

A new gene <Emphasis Type="Italic">Bph33</Emphasis>(<Emphasis Type="Italic">t</Emphasis>) conferring resistance to brown planthopper (BPH), <Emphasis Type="Italic">Nilaparvata lugens</Emphasis> (Stål) in rice line RP2068-18-3-5

The rice brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the major pests of rice across Asia. Host-plant resistance is the most ecologically acceptable means to manage this pest. A rice breeding line RP2068-18-3-5 (RP2068) derived from the land race Velluthacheera is reported to be resistant to BPH populations across India. We identified a new R gene [Bph33(t)] in this line using advanced generation RILs derived from TN1 × RP2068 cross through phenotyping at two locations and linkage analysis with 99 polymorphic SSR markers. QTL analysis through IciMapping identified at least two major QTL on chromosome 1 influencing seedling damage score in seed box screening, honey dew excretion by adults and nymphal survival. Since no BPH R gene has been reported on chromosome 1, we designate this locus as a new gene Bph33(t) which accounted for over 20% of phenotypic variance. Scanning the region for candidate gene suggested two likely candidates a leucine rich repeat (LRR) gene and a heat shock protein (HSP) coding gene. Expression profiling of the two genes in the two contrasting parents and RILs showed induction of the HSP gene (LOC_Os01g42190.1) at 6 h after infestation while LRR gene did not show such induction. It is likely that the HSP represented Bph33(t).     

Shrimp lectin–conjugated copper sulfide nanoparticles enhance immune response and gene expression in Etroplus suratensis infected with Aeromonas hydrophila

Aquaculture International - Lectins are hemagglutinating glycoproteins which act as pathogen recognition receptors that can bind to the pathogen-associated molecular patterns. Shrimp lectin...     

Polyphenolics Profile, Antioxidant and Radical Scavenging Activity of Leaves and Stem of Raphanus sativus L.

Aerial parts (leaves and stem) of Raphanus sativus, which are usually discarded were found to possess potent antioxidant and radical scavenging activity, as measured by standard antioxidant assays. Methanolic and acetone extracts of R. sativus leaves had total polyphenolic content of 86.16 and 78.77 mg/g dry extract, which were comparable to the traditional rich sources such as green tea and black tea. HPLC identification of polyphenolics indicated the presence of catechin, protocatechuic acid, syringic acid, vanillic acid, ferulic acid, sinapic acid, o-coumaric acid, myricetin, and quercetin in leaves and stem. Among the different extraction solvents, methanolic extract of leaves and stem showed potent reductive capacity, significantly inhibited linoleic acid peroxidation and displayed metal chelating activity. Further, they scavenged free radicals effectively with IC₅₀ (half maximal inhibitory concentration) of 31 and 42 μg/ml for DPPH radical, 23 and 52 μg/ml for superoxide radical, 67 and 197 μg/ml for hydrogen peroxide, and 56 and 62 μg/ml for nitric oxide, respectively. Leaves showed most potent antioxidant and radical scavenging activity as compared to stem, which may be accounted for the high polyphenolic content. Leaves and stem of R. sativus, often under-utilized part of this vegetable, thus possessed considerable amount of polyphenolics. Hence, it should be regarded as a potential source of natural antioxidants and could be effectively employed as an ingredient in health or in functional food.