Modulation of GmFAD3 expression alters abiotic stress responses in soybean

KEY MESSAGE

This study focused on enhancing resilience of soybean crops to drought and salinity stresses by overexpression of GmFAD3A gene, which plays an important role in modulating membrane fluidity and ultimately influence plants response to various abiotic stresses. Fatty acid desaturases (FADs) are a class of enzymes that mediate desaturation of fatty acids by introducing double bonds. They play an important role in modulating membrane fluidity in response to various abiotic stresses. However, a comprehensive analysis of GmFAD3 in drought and salinity stress tolerance in soybean is lacking. We used bean pod mottle virus (BPMV)-based vector for achieving rapid and efficient overexpression as well as silencing of Omega-3 Fatty Acid Desaturase gene from Glycine max (GmFAD3) to assess the functional role of GmFAD3 in abiotic stress responses in soybean. Higher levels of recombinant BPMV-GmFAD3A transcripts were detected in overexpressing soybean plants. Overexpression of GmFAD3A in soybean resulted in increased levels of jasmonic acid and higher expression of GmWRKY54 as compared to mock-inoculated, vector-infected and FAD3-silenced soybean plants under drought and salinity stress conditions. The GmFAD3A-overexpressing plants showed higher levels of chlorophyll content, efficient photosystem-II, relative water content, transpiration rate, stomatal conductance, proline content and also cooler canopy under drought and salinity stress conditions as compared to mock-inoculated, vector-infected and FAD3-silenced soybean plants. Results from the current study revealed that GmFAD3A-overexpressing soybean plants exhibited tolerance to drought and salinity stresses. However, soybean plants silenced for GmFAD3 were vulnerable to drought and salinity stresses.

Use of Phenomics for Differentiation of Mungbean (Vigna radiata L. Wilczek) Genotypes Varying in Growth Rates Per Unit of Water

In the human diet, particularly for most of the vegetarian population, mungbean (Vigna radiata L. Wilczek) is an inexpensive and environmentally friendly source of protein. Being a short-duration crop, mungbean fits well into different cropping systems dominated by staple food crops such as rice and wheat. Hence, knowing the growth and production pattern of this important legume under various soil moisture conditions gains paramount significance. Toward that end, 24 elite mungbean genotypes were grown with and without water stress for 25 days in a controlled environment. Top view and side view (two) images of all genotypes captured by a high-resolution camera installed in the high-throughput phenomics were analyzed to extract the pertinent parameters associated with plant features. We tested eight different multivariate models employing machine learning algorithms to predict fresh biomass from different features extracted from the images of diverse genotypes in the presence and absence of soil moisture stress. Based on the mean absolute error (MAE), root mean square error (RMSE), and R squared (R ²) values, which are used to assess the precision of a model, the partial least square (PLS) method among the eight models was selected for the prediction of biomass. The predicted biomass was used to compute the plant growth rates and water-use indices, which were found to be highly promising surrogate traits as they could differentiate the response of genotypes to soil moisture stress more effectively. To the best of our knowledge, this is perhaps the first report stating the use of a phenomics method as a promising tool for assessing growth rates and also the productive use of water in mungbean crop.

Telemedicine: Embracing virtual care during COVID-19 pandemic

Telemedicine and related e-health facilities facilitate care from a distance through electronic information systems. COVID-19 pandemic is establishing telemedicine in the health care delivery system of countries. Telehealth is contributing significantly in health care delivery during the COVID-19 crisis. For mild-to-moderate symptoms of COVID-19 or any illness, telehealth services might represent a better, efficient way to receive initial care and perform triaging. Telemedicine also has a significant role in screening for COVID-19 symptoms and delivering routine needs and follow-up care. The large-scale adoption of telemedicine in public health care delivery is still not visible in low- and middle-income countries like India. Adoption by patients and healthcare professionals is limited and their concerns need to be addressed to ensure its utilization in future of the care continuum. In the current paper, we aim to review recent measures of Telemedicine adopted during the course of pandemic and its impact on public health in lower-middle income countries like India.

Multi-trait PGP rhizobacterial endophytes alleviate drought stress in a senescent genotype of sorghum [Sorghum bicolor (L.) Moench]

Root-tissue colonizing bacteria demonstrated with multiple PGP traits from sorghum plants were identified as Ochrobactrum sp. EB-165, Microbacterium sp. EB-65, Enterobacter sp. EB-14 and Enterobacter cloacae strain EB-48 on the basis of 16S rRNA gene sequencing. Here, the in vivo experiments using ½-MS media and ½-MS media + 15% PEG 8000 (for inducing drought stress) indicated stress tolerance imparting ability of these rhizobacterial endophytes in a non-stay green and senescent genotype (R-16) of sorghum. In the experiment with sterile soilrite mix base, seed bacterization with these isolates showed improved plant growth specifically the roots, in terms of root length (~ 44.2 to 50.8% over controls), root dry weight (~ 91.3 to 99.8% over controls) and root surface area (~ 1 to 1.5 fold over controls) under drought stress. Rhizobacterial endophytes were successful, not only in providing better cellular osmotic adjustment in leaves (≥ 1-fold increase in proline accumulation over controls), but favorable physiological responses like Relative Water Content (RWC) and cell Membrane Stability Index (MSI) in the inoculated plants during the drought stress induction. Up-regulation of drought responsive genes like sbP5CS2 and sbP5CS1 was observed in these endophytes-treated plants as compared to untreated control and Escherichia coli DH5α (negative control)-treated plants. Interestingly, the stress imparting traits of rhizobacterial endophytes, including up-regulation of specific genes, were observed during sorghum seedling growth only under drought stresses. The results of this study lead to the conclusion that the potential endophytic rhizobacterial interactions can contribute to plant growth promotion as well as induced stress tolerance in sorghum.

Assimilates mobilization, stable canopy temperature and expression of expansin stabilizes grain weight in wheat cultivar LOK-1 under different soil moisture conditions

BACKGROUND

Grain yield of wheat is primarily determined by both grain number and grain weight, which often influence each other in response to environmental stimuli. Some of the genotypes are capable of maintaining high single grain weight (SGW) across the environments. Understanding mechanisms and factors associated with the superiority of such genotypes over others is necessary to enhance productivity of wheat.

RESULTS

Experiments were conducted to elucidate the physiological basis of high SGW of LOK-1, a wheat cultivar grown in dry and hot environments in the central and peninsular zones of India. SGW of LOK-1 was least affected by removal of spikelets indicating little competition between the grains within the spike for assimilates. Reduction in SGW due to defoliation was less and the contribution of stem reserves to the grain development was high in LOK-1 relative to other cultivars. It seems that high level of expression of genes such as expansin (TaExpA6) contributes to the high SGW of LOK-1.

CONCLUSIONS

Source was not a limiting factor for grain growth of LOK-1 in contrast to other cultivars, whereas sink appeared to be a limiting factor in recently released/identified cultivars. Differences in the amounts of water soluble stem carbohydrate reserves translocated to grain could be one of the factors contributing to higher grain weight in LOK-1. High level expression of TaExpA6, one of the genes contributing to the elongation of endosperm, seems to be crucial for grain growth in wheat.

Comparative conventional and phenomics approaches to assess symbiotic effectiveness of Bradyrhizobia strains in soybean (Glycine max L. Merrill) to drought

Symbiotic effectiveness of rhizobitoxine (Rtx)-producing strains of Bradyrhizobium spp. in soybean (cultivar NRC-37/Ahilya-4) under limited soil moisture conditions was evaluated using phenomics tools such as infrared(IR) thermal and visible imaging. Red, green and blue (RGB) colour pixels were standardized to analyse a total of 1017 IR thermal and 692 visible images. Plants inoculated with the Rtx-producing strains B. elkanii USDA-61 and USDA-94 and successive inoculation by B. diazoefficiens USDA-110 resulted in cooler canopy temperatures and increased canopy greenness. The results of the image analysis of plants inoculated with Rtx-producing strains were correlated with effective nodulation, improved photosynthesis, plant nitrogen status and yield parameters. Principal component analysis (PCA) revealed the reliability of the phenomics approach over conventional destructive approaches in assessing the symbiotic effectiveness of Bradyrhizobium strains in soybean plants under watered (87.41-89.96%) and water-stressed (90.54-94.21%) conditions. Multivariate cluster analysis (MCA) revealed two distinct clusters denoting effective (Rtx) and ineffective (non-Rtx) Bradyrhizobium inoculation treatments in soybean. Furthermore, correlation analysis showed that this phenotyping approach is a dependable alternative for screening drought tolerant genotypes or drought resilience symbiosis. This is the first report on the application of non-invasive phenomics techniques, particularly RGB-based image analysis, in assessing plant-microbe symbiotic interactions to impart abiotic stress tolerance.

Wounding activates a 47 kDa MAP kinase in Catharanthus roseus (L.) G. Don

Catharanthus roseus (L.) G. Don. is an important medicinal plant (Fam. Apocynaceae) known for its alkaloids that are accumulated in response to various biotic and abiotic stresses including wounding. Mitogen activated protein (MAP) kinases are important components of cellular signaling system transducing these stress stimuli into intracellular responses by phosphorylation of downstream transcription factors, regulators or inhibitors leading to expression of stress responsive genes. Here, we report the activation of a 47 kDa MAP Kinase in C. roseus in response to wounding. The immunoprecipitation coupled with in-gel kinase assay revealed tyrosine phosphorylation of the protein. Partial purification of the MAP kinase was also attempted. We observed a size variation for the kinase when purified using different schemes.

Prevalence of autism spectrum disorders among children (1-10 years of age) - findings of a mid-term report from Northwest India

Background:

India is the second most populous country of the world. A large portion of the population of this country is below 20 years of age but still there is a paucity of information about the prevalence and incidence of many developmental disorders. This study was planned to estimate the prevalence of autism spectrum disorders (ASDs) in the selected areas (tribal, rural, and urban) of a northern state of India, Himachal Pradesh.

Methods:

A cross-sectional two-phase study was conducted covering all the children in the range of 1-10 years of age. Phase one included screening of all the children in the age group of 1-10 years, with the help of an indigenous assessment tool for autism. The sociodemographic profile of the participants was also recorded during phase one. Phase two involved the clinical evaluation of individuals who were suspected of autism on screening.

Results:

The results show a prevalence rate of 0.9/1000. The highest prevalence rate was observed in the rural area.

Conclusions:

Socioeconomic status (SES) may be one of the fundamental indicators for ASDs in India.

Intersecting pentagons as surrogate for identifying the use of mini mental state examination in assessment of dementia in a largely illiterate population

Background and Rationale:

The mini-mental state evaluation (MMSE) is often used to identify patients with dementia. One component of the MMSE is the intersecting pentagon copying (IPC) test, which may be difficult to be used in an illiterate population.

Materials and Methods:

A post hoc analysis on an elderly population (60 years and above) from Himachal Pradesh was carried out. The data of only 1,513 elderly individuals out of a total of 2,000 participants with a score of more than 26 (nondemented) out of a possible score of 30 on cognitive battery available were used. The scores on the IPC were evaluated and their association with some demographic variables was also assessed.

Results:

Illiterate participants, female participants, those with greater age, and the rural/tribal population groups faced the most difficulty in drawing the intersecting pentagons and even greater difficulty in drawing them correctly.

Discussion:

The IPC presents challenges for people who are illiterate and the scoring method needs to be addressed and changed particularly when the test is used in largely illiterate populations.

Impact of method of application and concentration of potassium on yield of wheat

A field experiment was conducted to study the effect of different levels and methods of potassium application on yield, K uptake and forms of potassium in wheat crop at experimental field of Division of Soil Science, Sher-e-Kashmir University of Agricultural Sciences and Technology, Kashmir. The treatment consisted of 5 levels of potassium (0, 20, 40, 60 and 80 kg K2O ha(-1)) and two methods of application viz Single basal and split (1/2 basal+1/2 at tiller initiation stage). Out of various treatments, split application of potassium @ 80 kg K2O ha(-1) was found superior to single basal application in terms of grain yield (43.20 q ha(-1)) and K uptake (22.89 kg ha(-1)) by grains at harvest. However, it was at par with split application of 60 kg K2O ha(-1). All forms of potassium viz water-soluble, exchangeable, available, boiling HNO3 extractable and lattice increased with increasing levels of potassium and were found maximum (3.20, 62.80, 66.00 ppm 0.723 and 1.440% respectively) when potassium was applied @ 80 kg K2O ha(-1) in two equal splits except for lattice K which was maximum (1.440%) when potassium was applied @ 60 kg K2O ha(-1).

Structure and properties of silk from the African wild silkmoth Gonometa postica reared indoors

African wild silkmoth, Gonometa postica Walker (Lepidoptera: Lasiocampidae), were reared indoors in order to examine the influence of rearing conditions on the structure and properties of silk cocoon shells and degummed fibers by using a scanning electron microscope, an Instron tensile tester, and a thermogravimetric analyzer. The cocoons reared indoors showed inferior quality in weight, length, width, and cocoon shell ratio compared to cocoons reared outdoors. There were no differences in cocoon shell and fiber surfaces and cross sectional structures. Cocoon shells were covered with calcium oxalate crystals with few visible fibers on their surface. Degummed fibers were smooth with minimum unfractured surfaces and globular to triangular cross sections. Indoor-reared cocoon shells had a significantly higher breaking strain, while the breaking stress was higher for cocoons reared outdoors. Fibers from indoor cocoons had a significantly higher breaking stress while outdoor fibers had higher breaking strain. Thermogravimetric analysis curves showed two main thermal reactions revealing the dehydration of water molecules and ir-reversible decomposition of the crystallites in both cocoons and fibers reared indoors and outdoors. Cocoon shells underwent additional peaks of decomposition with increased temperature. The total weight loss was higher for cocoon shells and degummed fibers from indoors. Rearing conditions (temperature and relative humidity), feeding method used, changes in total life span, days to molting, and spinning might have influenced the variation in the properties observed.The ecological and commercial significances of indoor rearing of G. posticaare discussed.

Dissolution properties of silk cocoon shells and degummed fibers from African wild silkmoths

Silk cocoon shells and degummed fibers from four African wild silkmoth species were studied and compared with the industrial standard, Bombyx mori, for their dissolution properties. Nine M aqueous Lithium bromide, Calcium chloride and Sodium thiocyanate solution systems were used. Efficiency of the solvent systems was determined by the percentage of dissolved silk cocoon shells and degummed fibers after three hours of treatment. Degummed fibers were more readily soluble than the cocoon shells. B. mori cocoon shells (51.5%) and fibers (59.3%) had higher solubility than their wild counterparts. Among the wild species, Gonometa postica cocoon shells and degummed fibers had the highest solubility (37.3 and 51.7%, respectively). Lithium bromide was the most effective dissolving agent for both the cocoon shells and fibers (41.2 and 84.5%, respectively). Argema mimosae, Anaphe panda and Epiphora bauhiniae showed lower solubility across the solution systems used. The Scanning Electron micrographs showed A. panda fibers exhibited gelling property after dissolution while E. bauhiniae and A. mimosae had cracked and broken fibers exposing the fibriliar structures. The difference in the chemical orientation and composition of the fibers might have contributed to the variability in the dissolution behaviour.

Catharanthus roseus mitogen-activated protein kinase 3 confers UV and heat tolerance to Saccharomyces cerevisiae

Catharanthus roseus is an important source of pharmaceutically important Monoterpenoid Indole Alkaloids (MIAs). Accumulation of many of the MIAs is induced in response to abiotic stresses such as wound, ultra violet (UV) irradiations, etc. Recently, we have demonstrated a possible role of CrMPK3, a C. roseus mitogen-activated protein kinase in stress-induced accumulation of a few MIAs. Here, we extend our findings using Saccharomyces cerevisiae to investigate the role of CrMPK3 in giving tolerance to abiotic stresses. Yeast cells transformed with CrMPK3 was found to show enhanced tolerance to UV and heat stress. Comparison of CrMPK3 and SLT2, a MAPK from yeast shows high-sequence identity particularly at conserved domains. Additionally, heat stress is also shown to activate a 43 kDa MAP kinase, possibly CrMPK3 in C. roseus leaves. These findings indicate the role of CrMPK3 in stress-induced MIA accumulation as well as in stress tolerance.

Effect of available nutrients on yield and quality of pear fruit Bartlett in Kashmir Valley India

Pear is one of the most important commercial crops grown in the Kashmir valley of India. A study was conducted during 2008 to find out the effect of available nutrients on yield and quality parameters of pear cultivar "Bartlett" which revealed that nitrogen, phosphorus and potassium exhibited significant and positive relationship with fruit length (0.882, 0.856, and 0.482 mm, respectively), diameter (0.869, 0.794 and 0.458 mm, respectively), weight (0.876, 0.825 and 0.439 g, respectively), volume (0.908, 0.806 and 0.404, Cm3 respectively) and yield (0.908, 0.764 and 0.702 kg tree(-1), respectively) however, only nitrogen and phosphorus showed similar relationship with total sugars (0.833 and 0.838% respectively). The calcium indicated significant and negative relationship with fruit diameter (-0.433) and yield (-0.589), while as it showed significant and positive correlation with fruit firmness (0.442) only. The sulphur revealed significant and positive relationship with fruit length (0.440), diameter (0.434), TSS (0.482) and yield (0.729) whereas zinc, copper, iron and manganese exhibited significant and positive relationship with fruit length (0.889, 793, 0.671 and 0.619, respectively), diameter (0.875, 0.807, 0.653 and 0.576, respectively) weight (0.881, 0.784, 0.669 and 0.615, respectively), volume (0.885, 0.832, 0.692 and 0.572, respectively) TSS (0.858, 0.761, 0.735 and 0.609, respectively), total sugars (0.853, 0.890, 0.705 and 0.517, respectively) and yield (0.777, 0.618, 0.789 and 0.701, respectively). It is therefore suggested that nutrients have effect on quality and yield of pear fruits.

CrMPK3, a mitogen activated protein kinase from Catharanthus roseus and its possible role in stress induced biosynthesis of monoterpenoid indole alkaloids

BACKGROUND

Mitogen activated protein kinase (MAPK) cascade is an important signaling cascade that operates in stress signal transduction in plants. The biologically active monoterpenoid indole alkaloids (MIA) produced in Catharanthus roseus are known to be induced under several abiotic stress conditions such as wounding, UV-B etc. However involvement of any signaling component in the accumulation of MIAs remains poorly investigated so far. Here we report isolation of a novel abiotic stress inducible Catharanthus roseus MAPK, CrMPK3 that may have role in accumulation of MIAs in response to abiotic stress.

RESULTS

CrMPK3 expressed in bacterial system is an active kinase as it showed auto-phosphorylation and phosphorylation of Myelin Basic Protein. CrMPK3 though localized in cytoplasm, moves to nucleus upon wounding. Wounding, UV treatment and MeJA application on C. roseus leaves resulted in the transcript accumulation of CrMPK3 as well as activation of MAPK in C. roseus leaves. Immuno-precipitation followed by immunoblot analysis revealed that wounding, UV treatment and methyl jasmonate (MeJA) activate CrMPK3. Transient over-expression of CrMPK3 in C. roseus leaf tissue showed enhanced expression of key MIA biosynthesis pathway genes and also accumulation of specific MIAs.

CONCLUSION

Results from our study suggest a possible involvement of CrMPK3 in abiotic stress signal transduction towards regulation of transcripts of key MIA biosynthetic pathway genes, regulators and accumulation of major MIAs.

Effect of sodium nitroprusside on morphological characters under chilling stress in chickpea (Cicer arietinum L.)

An experiment was conducted with chilling tolerant (IC-424234) and sensitive (PBG-1) chickpea (Cicer arietinum L.) genotypes to study the effect of sodium nitroprusside (SNP)- nitric oxide donor applied as foliar spray of 150 and 300 microM concentrations at 45 DAS (vegetative stage), 85 DAS (flowering stage) and 125 DAS (post flowering stage). Both the concentrations of SNP (150 and 300 microM) resulted in significant increase in all the morphological characters viz. plant height, number of leaves plant1, leaf area plant(-1) and leaf area index (LAI) over the control at all the stages, though lower concentration (150 microM) was more effective. Chilling sensitive (CS) genotype PBG-1 responded more effectively to SNP treatment. Electrolyte leakage percentage was effectively reduced by SNP treatments in both the genotypes at low temperature (15 DAA). Chilling sensitive genotype PBG-1 treated with SNP (150 microM) recorded significantly higher yield contributing characters viz. number of pods plant1, number of seeds pod(-1), seed yield plant1(g), pod setting percentage (%), 100 seed weight (g) and yield (kg ha(-1)) over the chilling tolerant (IC-424234)

Scoring the medical outcomes among HIV / AIDS patients attending antiretroviral therapy center at Zonal Hospital, Hamirpur, using Patient Satisfaction Questionnaire (PSQ-18)

AIM

To study level of satisfaction among patients attending ART centre using Patient Satisfaction Questionnaire (PSQ - 18).

MATERIALS AND METHODS

A cross-sectional interview based technique was used to study the level of satisfaction.

RESULTS

A total of 59 patients attending ART centre were included in the study. The mean score for general satisfaction was 3.22 (SD 0.86), for technical quality 3.03 (SD 0.92), for the interpersonal manner 3.25 (SD 0.93), for communication (SD 0.90), for financial aspects was 2.38 (SD 1.00) and for time spent during the visit, the mean score was 2.97 (SD 0.98)

INTERPRETATION

Patient satisfaction is the key in planning and formulating guidelines for treatment and care.

Comparative studies on morphological and biochemical characters of chickpea genotypes under chilling stress

Comparison of chickpea (Cicer arietinum L.) genotypes for morphological and biochemical attributes was done. Morphological characters viz. Plant height, number of branches and number of leaves were recorded highest in chilling tolerant genotypes at early stages of development (30 and 60 DAS) whereas at later stages (90 and 120 DAS) these characters were recorded highest in chilling sensitive genotypes. Pollen viability percentage at 5 and 10 degrees C temperatures were recorded highest in chilling tolerant genotypes as compared to sensitive genotypes. Biochemical characters viz. electrolyte leakage (%), total soluble sugars and total free amino acids were recorded highest in chilling tolerant genotypes as compared to sensitive genotypes.

Direct, residual and direct + residual effects of sulphur in garlic (Allium sativum)-maize (Zea mays) cropping sequence

Significant positive effects of 30 kg/ha of sulphur as manifested on yield and yield parameters of garlic were further carried over to following maize crop. Garlic bulb and foliage yield (6.3 and 0.8 t/ha respectively) obtained at 30 kg/ha of sulphur dose was significantly higher over without sulphur (3.7 and 0.5 t/ha respectively) as revealed from two years' pooled data. Similarly number of leaves/plant, weight of cloves/5bulbs and weight/100 cloves at the said sulphur dose significantly increased over without sulphur from 10.5 to 11.9, 98.3 to 141.2 g and from 159 to 217 g in respective manner Increase in grain yield of maize (residual effect) and in the economic yield of the whole cropping sequence (Bulb yield of garlic and grain yield of maize) i.e. direct plus residual effect at 30 kg/ha of sulphur dose over without sulphur was from 28.3 to 47.2 and from 71 to 116 q/ha in respective manner i.e. with significant differences. Sulphur use efficiencies (kg yield/kg sulphur) of these crops at 15, 30 and 45 kg/ha over no sulphur were 57, 43 and 32; 53, 63 and 6 and 160, 150 and 67, all in respective order An optimum sulphur dose of 44.3 kg/ha produced increased bulb yield (over no S) worth Rs 34892 over fertilizer cost giving B:C ratio of 31.5:1. Utilization of sulphur added at 15, 30 and 45 kg/ha rates was 24.1, 19.3 and 15.7% by the garlic crop; and 29.6. 24.5 and 9.02% by the following maize crop, thus, adding up to 54.1, 43.8 and 24.9% by the cropping sequence, all in respective order.

Elite Indica transgenic rice plants expressing modified Cry1Ac endotoxin of Bacillus thuringiensis show enhanced resistance to yellow stem borer (Scirpophaga incertulas)

Bt-transgenics of elite indica rice breeding lines (IR-64, Pusa Basmati-1 and Karnal Local) were generated through biolistic or Agrobacterium-mediated approaches. A synthetic cry1Ac gene, codon optimised for rice and driven by the maize ubiquitin-1 promoter, was used. Over 200 putative transformants of IR-64 and Pusa Basmati-1 and 26 of the Karnal Local were regenerated following use of the hpt (hygromycin phosphotransferase) selection system. Initial transformation frequency was in the range of 1 to 2% for particle bombardment while it was comparatively higher (approximately 9%) for Agrobacterium. An improved selection procedure, involving longer selection on the antibiotic-supplemented medium, enhanced the frequency of Bt-transformants and reduced the number of escapes. Molecular evaluation revealed multiple transgene insertions in transformants, whether generated through biolistic or Agrobacterium. In the latter case, it was also observed that all genes on the T-DNA do not necessarily get transferred as an intact insert. Selected Bt-lines of IR-64 and Pusa Basmati-1, having Bt-titers of 0.1% (of total soluble protein) and above were evaluated for resistance against manual infestation of freshly hatched neonate larvae of yellow stem borers collected from a hot spot stem borer infested area in northern India. Several Bt-lines were identified showing 100% mortality of larvae, within 4-days of infestation, in cut-stem as well as vegetative stage whole plant assays. However, there was an occasional white head even among such plants when assayed at the reproductive stage. Results are discussed in the light of resistance management strategies for deployment of Bt-rice.

High-frequency embryogenesis and plantlet regeneration from isolated microspores of indica rice

We report high-frequency embryogenesis and plantlet development from microspores isolated from anthers of two indica (IR-43, IR-54) and a japonica (T-309) rice cultivars, without prior nutrient preculture of anthers. Pretreatment stress of anthers with mannitol or a sugar-starvation medium, and use of maltose as the carbohydrate source in the microspore culture medium were found to be critical. Co-culture of microspores with rice ovaries was found beneficial but not essential. More than 60% of the microspores of the japonica variety Taipai-309 and 25-45% of the indica cultivars IR-54 and IR-43 showed induction of non-gametophytic development. Consequently, in the best treatments for IR-43 and T-309, more than 500 microspore-derived embryos could be obtained from a single dish (35 mm) containing about 80,000 microspores. Among the indica cultivars, the maximum response was obtained in the basal medium M-019. Plantlet regeneration occurred in about 9% (T-309), 7% (IR-43) and 2% (IR-54) of the transferred embryo-like structures.

Transovarial transmission of Nosema locustae (Microsporida: Nosematidae) in the migratory locust Locusta migratoria migratorioides

Nosema locustae, a microsporidian parasite of locusts and grasshoppers, was transovarially transmitted to the progeny of infected Locusta migratoria reared for up to F14 generations. The mortality of infected progeny in each generation was higher than that of uninfected controls and ranged from 67.6% to 95.5%. Infected female survivors transmitted the microsporidium to the progeny via eggs. The developing eggs harboured vegetative stages of N. locustae, and development of the microsporidium occurred during embryonation. Spores accumulated in the yolk and, after blastokinesis, both the yolk and the spores were enclosed in the midgut of the embryo. Germinated spores infected the functional midgut epithelium and invaded internal tissues. The mortality of newly hatched instars was high when embryonic tissue had been infected during development.

In vitro propagation of Nosema locustae using fat body cell line derived from Mythimna convecta (Lepidoptera: Noctuidae)

Nosema locustae, a microsporidian parasite of locusts and grasshoppers, was successfully propagated in a fat body cell line from Mythimna convecta (BPMNU-MyCo-1). The fat body cells were grown in MGM-448 medium supplemented with 5% fetal bovine serum and 3% Bombyx mori serum at 25 degrees C. Cultures were inoculated with Nosema spores and agitated for 2 min. Infection appeared 3 days post-inoculation and by 7th day, some cells were filled with spores. At the 15th day post-inoculation, 32% of the fat body cells were infected. After isolation, the spore yield ranged from 1.4 x 10(6) spores/ml. Infected cells were subcultured and by the 4th passage spore production decreased. Harvested spores were found infectious to Locusta migratoria.

A study of serum zinc, albumin, alpha-2-macroglobulin and transferrin levels in acute and long stay elderly hospital patients

Serum zinc levels measured by atomic absorption spectrophotometry were found to be low (less than 10.5 mumols/l) in 38% of acute geriatric admissions, 69% of long stay geriatric patients and 19% of a control group of elderly hospital patients with a normal serum albumin. There was a significant positive correlation between serum zinc and serum albumin in all groups. In acutely ill geriatric patients only, there was a weak but statistically significant positive correlation between serum zinc and alpha-2-macroglobulin (A2M) (r = 0.20), P less than 0.05). Serum transferrin was low in 46% of acute geriatric patients and 22% of long stay geriatric patients but there was no correlation between serum zinc and serum transferrin levels in any patient group. There were significant differences in serum zinc, A2M and transferrin levels between the acute and long stay geriatric patients. The differences in serum zinc levels between these patients groups could not be explained by changes in serum A2M, transferrin or albumin. Changes mediated by an acute phase response may have influenced results in the acute geriatric group of patients.

Plant regeneration from in vitro cultures of anthers and mature seeds of rice (Oryza sativa L.) cv. Basmati-370

Pollen plants were obtained from anther-derived calli of the indica rice variety Basmati-370. Anther-response (anthers producing pollen derived calli) and plant regeneration frequency from the pollen derived calli. was very low. Donor plants which flowered at the average max/min. temperature of 34.2°/23.3°C gave a significantly higher anther-response to in vitro techniques, than did those which flowered at 29.1°/16.4°C. Somatic callus induction and subsequent plant regeneration was readily obtained from mature seed embryos. While 2,4-D or 2,4,5-T (1 or 2 mg/l) proved highly efficient for callus induction, tryptophan (50 or 100 mg/l) induced a high frequency of green plants from the calli.

The early ontogeny of embryoids and callus from pollen and subsequent organogenesis in anther cultures of Datura metel and rice

Haploidy induction through anther culture has been examined in Datura metel and rice with a view to tracing the precise sequence of development of the pollen, either directly or through an intervening callus, into an embryo and seedling. In D. metel, the vegetative cell of the young pollen grain assumes the major role in formation of embryos whereas the generative cell and its few derivatives degenerate. Embryos and seedlings arising directly from pollen without an intervening callus phase always proved to be haploids, whereas those differentiating from pollen-derived callus gave haploid, diploid and even triploid plants. Cytological analysis of callus tissue showed cells of various ploidy levels ranging from haploid to triploid, and in rare instances even with higher chromosome numbers.In rice anther cultures the embryoids arose from an initial callus phase. Of 15 different rice cultivars tried, only four produced a callus, and in only one, was there differentiation of plants, both haploid and diploid ones. Among other species tried, egg plant has also yielded plantlets through a callus phase whereas only callus production has been achieved in jute, tea and petunia. No response has been obtained in wheat, maize, cotton and coconut.Coconut milk (CM) appears to be the most important component of the medium for the initial induction of embryoids and callus in anther cultures of most of the species tried. However, further growth and differentiation of plants may require a simpler medium; in D. metel, continued culture on CM led to dedifferntiation.