The response of chilli (Capsicum annuum L.) plants to early inoculation with mycorrhizal fungi at different levels of phosphorus

Summary

Chilli plants cv. Pusa Jwala were inoculated in the nursery beds with three mycorrhizal fungi, Gigaspora calospora, G. margarita and Glomus fasciculatum and transplanted to plots supplied with 0, 25 and 50% of a recommended P level (65 kg ha^?1). Uninoculated plants were also transplanted at 0 (Control) and 100% of.the recommended P level. Plant growth, height, shoot dry weight, uptake of P, root colonization and yield of green chillies were measured. Chilli responded well to inoculation and P. G. margarita best improved growth and yield. Inoculation plus 25 and 50% P were equally better than the control and equal to uninoculated plants at 100% P. As much as 50–75% P can be dispensed with by inoculation with mycorrhizal fungi and this represents a considerable economic saving in cost.     

Interspecific hybridization in Gossypium L.: characterization of progenies with different ploidy‐confirmed multigenomic backgrounds

Cytological and molecular investigations were undertaken for parent and progeny derived from a trispecific line [2(Gossypium arboreum × G. anomalum) × G. hirsutum var. BWR], which was crossed with G. hirsutum var. JLH168. Cytomorphological analysis of the F₁ (G. arboreum × G. anomalum), its amphidiploid and progeny from trispecies hybrid showed distorted ploidy segregation with monovalents to hexavalents and high intergenomic (small A₂ and large B₁) allosynthetic chromosome pairing. Microsatellite analysis identified three fragments associated with G. arboreum and G. anomalum and six fragments associated with G. hirsutum in derivates of the trispecies line × G. hirsutum var. JLH168. Inter‐Retrotransposon Amplified Polymorphism (IRAP) analysis revealed fragments of G. arboreum and G. anomalum, only in F₁ and amphidiploid. Chromosomal association and microsatellite analysis of three progeny genotypes (i.e. haploid, hexaploid and tetraploid no. 1) confirmed that they share multigenomic background from the three cotton species (A₂, A_hD_h and B₁ genome). The interspecific hybrid cotton genotypes studied are likely to be useful for the introgression of genes from diploid species to commercial upland cultivars.     

Simulation of rice planthopper damage for developing pest management decision support tools

Rice planthoppers' damage on Pusa Basmati 1 cultivar was simulated with InfoCrop, a generic crop growth simulation model. The model was calibrated and validated with two experimental data sets on planthopper population and rice yield that were generated through differential insecticide application during the rainy season 2006 and 2007. Simulated yield and total dry matter (TDM) in various treatments over the two experiments were found to be proximal to the observed yields (R² = 0.972, RMSE = 4.61%) and TDM (R² = 0.949, RMSE = 3.25%), respectively. Likewise, the simulated yield and TDM losses were also respectively close to observed yield losses (R² = 0.938, RMSE = 13.53%) and TDM losses (R² = 0.835, RMSE = 19.12%), suggesting appropriate validation of planthopper damage mechanism on Pusa Basmati 1 rice. Economic injury levels (EILs) of planthoppers were simulated with two control expenditures involving two applications with each of monocrotophos and imidacloprid, and three market prices of Pusa Basamti 1 rice. The EIL exhibited a negative relationship with market value of produce but a positive one with expenditure on control measures. Simulated EILs were comparable to earlier established empirical EILs, indicating utility of simulation models for developing location specific EILs that may help in doing away with the use of blanket EILs. Iso-loss curves, devised through validated model, depicted combinations of crop age and planthopper population that resulted in similar yield losses. Both the EILs and iso-loss curves can be useful in monitoring planthopper populations and promoting judicious pesticide applications that would avoid unwarranted control expenditure and environmental contamination. The simulation models being based on detailed crop ecological and physiological processes and pest damage mechanism can thus aid in development of location-specific decision support tools and ensure precision in pest management decisions.     

Indian Herbal Medications to Replace Antibiotics for Shrimp Penaeus monodon Post Larvae

Herbs with known antibacterial characteristics were chosen and extracted with different polar and non-polar solvents and screened against five different shrimp pathogens: Pseudomonas aeruginosa, Staphylococcus aureus, Aeromonas hydrophila, Vibrio harveyi, and V. parahaemolyticus. Five different diets were prepared by incorporating equal proportions of these five herbal extracts at increasing concentrations: Control (0), HD1 (200), HD2 (400), HD3 (600), and HD4 (800 mg/kg of diet). Diets were individually fed to the Penaeus monodon post larvae (PL 25) for 30 days. At 10-day intervals, post larvae were bath challenged with V. harveyi and observed for pathological signs. Post larvae fed the HD 4 diet enjoyed a 75% improvement in survival over the control group and significantly improved final weights and SGR (P < 0.05). The herbal diets HD1 to HD4 helped to decrease the Vibrio load in P. monodon post-larvae after challenging.     

Nano-sized albumin-copolymer micelles for efficient doxorubicin delivery

We present the discovery of a nano-sized protein-derived micellar drug delivery system based on the polycationic albumin precursor protein cBSA-147. The anticancer drug doxorubicin (DOX) was efficiently encapsulated into nanosized micelles based on hydrophobic interactions with the polypeptide scaffold. These micelles revealed attractive stabilities in various physiological buffers and a wide pH range as well as very efficient uptake into A549 cells after 1 h incubation time only. In vitro cytotoxicity was five-times increased compared to free DOX also indicating efficient intracellular drug release. In addition, multiple functional groups are available for further chemical modifications. Based on the hydrophobic loading mechanism, various classical anti-cancer drugs, in principle, could be delivered even synergistically in a single micelle. Considering these aspects, this denatured albumin-based drug delivery system represents a highly attractive platform for nanomedicine approaches towards cancer therapy.     

Simulation of leaf folder,Cnaphalocrocis medinalis (Guenee), damage on rice for developing decision support tools

Simulation models are synonymous with the application of the systems approach in pest management and help to formulate decision support tools for an effective decision-making. A study was undertaken to improve our earlier work on simulation of rice leaf folder (Cnaphalocrocis medinalis) damage and to develop decision support tools for its management. Currently, the leaf folder damage on Pusa Basmati1 rice was simulated with data sets generated in two field experiments during the rainy season 2008 and 2009. Simulated yields and total dry matter in different treatments over the experiments were close to their observed counterparts, indicating an appropriate validation of the leaf folder damage mechanisms on Pusa Basmati1 rice. The leaf folder economic injury levels were simulated based on control expenditure on application of cartap hydrochloride 50SP and quinalphos 25SC, and market price of Pusa Basamti1. The simulated economic injury levels of the leaf folder were more precise than that simulated in our previous study. Likewise, iso-loss curves represented combinations of crop age and the leaf folder damage that resulted in a similar yield loss. These decision support tools would facilitate accurate monitoring of the leaf folder damage to ensure judicious pesticide application.     

Development and Identification of Novel Rice Blast Resistant Sources and Their Characterization Using Molecular Markers

To develop and characterize introgression lines for leaf and neck blast resistance, 326 introgression lines were developed using various accessions of six different AA genome wild species in the genetic background of elite Indian varieties like PR114 and Pusa 44 and were screened for blast resistance. Stringent phenotyping coupled with genotyping using gene based markers led to the identification of four resistant introgression lines, which showed promising resistance and do not possess any of the tested genes. Furthermore, multi-location screening confirmed the field resistance of the four introgression lines to both leaf and neck blast. Molecular characterization of these introgression lines using genome-wide simple sequence repeat markers revealed the presence of small percentage of wild Oryza genome introgrssion. So these lines can be used for mapping and identification of novel leaf and neck blast resistance genes. Thus, these four introgression lines can be considered as new genetic resources for blast resistance.