Natural compounds enhancing growth and survival of rhizobial inoculants in vermicompost-based formulations

The present study demonstrates the usefulness of natural microbial growth-promoting compounds for improving the stability and life of vermicompost-based (both granular and its aqueous extract) bioformulations. Granular vermicompost maintained the number of cells of Rhizobium meliloti Rmd 201 up to 5.9 × 10⁸ after 180 days at 28°C compared with 2.1 × 10⁸ in charcoal (powdered), while aqueous extract of the vermicompost supported the 5.6 × 10⁷ rhizobia numbers even after 270 days. The addition of 25 μL/mL cow urine and 0.01 mM calliterpinone, a natural plant growth promoter, increased the rhizobia number significantly in granular vermicompost and its aqueous extract, respectively.     

Genetic divergence in parental genotypes and its relation with heterosis, F1 performance and general combining ability (GCA) in opium poppy (Papaver somniferum L.)

Summary Genetic divergence in 110 population (20 parents and 90 F₁ hybrids) of opium poppy was studied by multivariate analysis. All the entries were grouped in 14 clusters. Out of 20 parents, ten were accumulated in one cluster and rest 10 distributed over seven clusters. Estimates of cluster distance showed that maximum intra-cluster distance was in -cluster IX (25.62) followed by cluster I (22.41), V (22.23) and IV (21.06). The inter cluster distances varied from 16.62 (between cluster XII and XIV) to 195.10 (between cluster IV and IX). The cluster analysis indicated substantial diversity among the parental genotypes, which had the potential to release considerable variation in their crosses. The first four principal components (PCs) with eigen values >1 accounted for 68% of variation among the population. The first and second components could account for 29 and 20% of the total morphological and alkaloidal variations, respectively. The PC1 was closely related to yield and yield related traits. The characters contributing greatest positive weight on PC1 were opium yield, plant height, stem diameter, capsule weight/plant and seed yield/plant. The possibilities of relationship between genetic divergence, F₁ performance, heterosis and GCA of parents have been explored.     

Inhibition of Iron Induced Lipid Peroxidation and Antioxidant Activity of Indian Spices and Acacia In Vitro

The spices used in the Indian foods such as Star anise (Illicium verum), Bay leaves (Cinnamomum zeylanicum) and Cobra’s saffron (Mesua ferrea), and Acacia (Acacia catechu), which have medicinal value, were used as test samples, to find their effect on in vitro lipid peroxidation (LPO). Rat liver post mitochondrial supernatant (PMS) in Tris HCl buffer, pH 7.4 was incubated for 0 and 1 h, with various test extracts in three different oxidant systems. The results show that addition of test samples to FeCl₃ medium at 0 h significantly stop the initiation of the LPO. However, the propagation phase of LPO was inhibited by Cobra’s saffron and Acacia and not by Star anise and Bay leaves. The test samples also showed strong reducing power and superoxide radical scavenging activity. Cobra’s saffron and Acacia showed the highest antioxidant activity, probably due to the higher polyphenol content as compared to other test samples.     

Crop performance in permanent raised bed rice–wheat cropping system in Punjab,India

Raised beds are widely used in agriculture in developed countries and have proven to be an excellent option for wheat. Permanent raised beds may also offer benefits for rice–wheat (RW) systems in South Asia, in terms of both production and the possibility that furrow-irrigation may be more efficient than flood irrigation. The performance of a RW system on permanent raised beds (37 cm wide, 15 cm high, furrow width 30 cm) was compared with conventional cultivation on the flat on sandy loam and loam soils in replicated experiments in central Punjab, India. The experiments commenced with wheat sown in November 2002, and were continued for 8 crops.     

Seed Number and 100‐Seed Weight of Pearl Millet (Pennisetum glaucum L.) Respond Differently to Low Soil Moisture in Genotypes Contrasting for Drought Tolerance

Water stress after flowering, one of the major factors limiting yields of pearl millet, affects both seed setting and grain filling and is a consequence of more/less water used prior to anthesis. However, whether genotypes have different sensitivities for seed setting and filling under drought, if exposed to similar stress intensity, is unclear. Experiments were conducted in two pairs of pearl millet genotypes, that is, PRLT2/89‐33 and H77/833‐2, 863B and 841B, contrasting for terminal drought tolerance, and two genotypes, ICMR 01046 and ICMR 01029 (IL‐QTLs), introgressed with a terminal drought tolerance QTL from PRLT2/89‐33 into H77/833‐2. Total seed weight, panicle number, 100‐seed weight, seed number and stover biomass were measured at different soil moistures and throughout grain filling. Sensitive H77/833‐2 had higher seed number and yield under well‐watered (WW) conditions than in PRLT2/89‐33 and IL‐QTLs. Upon increases in water stress intensity, H77/833‐2 suffered losses mostly in stover biomass (45 %) and seed number (60 %) at 0.3 FTSW whereas the biomass and seed number of PRLT2/89‐33 decreased little (20 % and 25 %). The 100‐seed weight of H77/833‐2 decreased only 20 % under stress. Tolerant 863B also maintained a higher seed number and biomass under water stress than 841B. Grain filling duration in PRLT2/89‐33 and IL‐QTLs was similar to that of H77/833‐2 under WW conditions but lasted longer than in H77833‐2 under water stress (WS). Similarly, seed growth of 863B was longer than 841B under WS. It is concluded that the higher seed yield of tolerant parents PRLT2/89‐33 and 863B, and of IL‐QTLs under WS was explained by the retention of a higher number of seeds than in sensitive lines, while the decrease in the 100‐seed weight was proportionally less than the decrease in seed number. Phenotype with lesser number and larger size of panicles and larger grain size, like genotypes PRLT2/89‐33 and 863B, withstood post‐anthesis water stress better. IL‐QTL inherited part of these characteristics, indicating a role for the terminal drought QTL in maintaining larger seed number and higher 100‐seed weight. The continuous stover biomass increase under WW in H77/833‐2, due to tillering, might indicate that tiller growth and grains are in competition for resources after anthesis, and this may relate to the relatively shorter grain‐filling period.     

Physiological and biochemical effects of salicylic acid on Pisum sativum exposed to isoproturon

In the present study, attenuation of isoproturon (IPU) toxicity by salicylic acid (SA) was observed. Seven-day-old seedlings of pea (Pisum sativum L. cv. Azad P-1) were treated with 10 mM IPU. IPU influenced physiological and biochemical parameters. IPU significantly inhibited growth variables like shoot and root height, fresh and dry biomass of the pea. The contents of carotenoids, chlorophylls, protein and activity of nitrate reductase were inhibited significantly. IPU enhanced the accumulation of H₂O₂, ion leakage and lipid peroxidation due to induction of oxidative stress in pea. The activities of antioxidant enzymes, namely superoxide dismutase, catalase and ascorbate peroxidase increased while the activities of guaiacol peroxidase decreased. However, exogenous SA regulated the toxic effects of IPU. The indices of oxidative stress appeared to be alleviated by SA. Pigment content and activities of enzymes increased approximately up to the level of control. IPU caused non-target phytotoxicity to P. sativum. The natural growth regulator/allelochemical has potential to overcome the adverse effects caused by IPU.

Abbreviations: CAT: catalase; EL: electrolyte leakage; IPU: isoproturon; LP: lipid peroxidation; MDA: malondialdehyde; NR: nitrate reductase; POD: guaiacol peroxidase; SOD: superoxide dismutase; TCA: trichloroacetic acid     

Structural characterization of corn fiber gums from coarse and fine fiber and a study of their emulsifying properties

The stabilities of orange oil emulsions stabilized with various concentrations of two different types of corn fiber gum (CFG-1 and 2) isolated from coarse (pericarp) and fine (endosperm) fiber from corn wet milling have been studied. The emulsion stabilities in all these studies increased with increasing gum concentration up to a gum-to-oil ratio of 0.05, and after that it either levels off or changes very slightly. These results indicate that only 0.25% of CFG is required to make stable emulsion containing 5% orange oil under the experimental conditions used in this study. At this CFG concentration, CFG-2 from each fiber source was found to be a superior emulsifier relative to the corresponding CFG-1 from each source in a 10-day emulsion stability study at room temperature. The emulsion stability was also investigated by confocal laser scanning microscopy measurement, and it was found that CFG-1 and 2 from both coarse and fine fiber made stable emulsions with an average particle size of less than 1 mum for 10 days at room temperature. Sugar composition analysis of CFGs from both sources indicated that they were typical galactoglucuronoarabinoxylans containing mainly 55-59% xylose, 29-36% arabinose, and 4-6% galactose as neutral sugars and 3-5% glucuronic acid. Methylation analysis revealed a highly branched structure of all CFGs, in which only 16-25% of the 1--> 4-linked xylose residues were not substituted at O-2 and/or O-3. Arabinose is present both as a terminal residue and at branch points.     

Target region amplification polymorphism (TRAP) for assessing genetic diversity and marker-trait associations in chickpea (Cicer arietinum L.) germplasm

The effective utilization of crop diversity held in genebanks depends on our knowledge of useful traits and available markers associated with the target traits. Target region amplification polymorphism (TRAP) was used to evaluate the genetic diversity and underlying relationships among 263 accessions of chickpea landraces maintained by the USDA-ARS Western Regional Plant Introduction Station in Pullman, WA, USA. Two-hundred sixty-two TRAP markers were amplified by eight primer combinations. Altogether, 110 (42 %) markers were polymorphic, the other 152 (58 %) displayed no variation. These polymorphic markers revealed important differences among the accessions, with an estimated, mean pair-wise genetic distance of 25.82 %, ranging from 2.8 to 50.0 %. Genetic distance analysis divided the accessions into two major groups, with 113 and 150 accessions each, and substantial association between molecular diversity and geographic origin was evident. Bayesian analysis of population structure revealed two groups (K = 2) with evidence for six sub-groups. Additionally, the population structure of a subset of 110 lines was determined (K = 3) for testing marker-trait associations (MTAs). Phenotypic traits included the concentrations of protein and nine mineral elements in the seeds. Two MTAs were significant (p < 0.01) for concentrations of Ca and K, and three MTAs were significant for Cu and Ni concentrations. The results indicate that this population is useful for genome-wide association studies on other economic traits given the level of genetic diversity uncovered and the marker-trait associations in seed minerals discovered.     

Decay of the GRB 990123 optical afterglow: implications for the fireball model

Broad-band (ultraviolet to near-infrared) observations of the intense gamma ray burst GRB 990123 started approximately 8.5 hours after the event and continued until 18 February 1999. When combined with other data, in particular from the Robotic Telescope and Transient Source Experiment (ROTSE) and the Hubble Space Telescope (HST), evidence emerges for a smoothly declining light curve, suggesting some color dependence that could be related to a cooling break passing the ultraviolet-optical band at about 1 day after the high-energy event. The steeper decline rate seen after 1.5 to 2 days may be evidence for a collimated jet pointing toward the observer.     

Strategies for maximizing utilization of de-oiled rice bran (DORB) in the fish feed

De-oiled rice bran (DORB) is obtained after oil is removed from the rice bran. This is the commonly used ingredient in the feeding of Indian major carps due to its cheaper cost. DORB is used as a feed ingredient in cattle, poultry, and fish diet. Along with this, they are also used in making fiber-rich biscuits and extraction of an antioxidant compound like oryzanol and other industrial uses. Due to the increased competition, there will be a huge imbalance in the demand and supply for this ingredient in the years to come. DORB is associated with high fiber content, anti-nutrients, and non-starch polysaccharides which lead to its poor utilization resulting in a higher feed conversion ratio (FCR) in fish. Hence, the strategic utilization of this ingredient by solid-state fermentation, exogenous enzyme supplementation, and supplementing it with deficient nutrients like amino acids and fatty acids will help in improving the utilization of this ingredient.