Glutamate wastewater as a culture medium for <Emphasis Type="Italic">Azospirillum rugosum</Emphasis> production and its impact on plant growth

Monosodium glutamate wastewater (MSGW) was used as a culture medium for Azospirillum rugosum strain IMMIB AFH-6 inoculant (In) by optimizing the dilution at 2.5% and pH 7.0 ± 0.1. A. rugosum growth studies were carried out in shake flasks and subsequently tested for plant growth promotion by seed germination bioassay and greenhouse pot experiments. The highest colony-forming units (cfu) 8.58 and 8.87 log cfu mL⁻¹, respectively, at 48 h of growth were recorded in MSGW and MSGW with yeast extract 0.04%. Seed bioassay results revealed that A. rugosum grown on MSGW stimulated the root and shoot elongation of maize (Zea mays L.) and pai tsai (Brassica chinensis L.). Pai tsai recorded significantly higher dry matter production when treated with A. rugosum and chemical fertilizers than control. The MSGW is a suitable culture medium for A. rugosum growth, and it is comparable to commercial media when tested for agricultural production.     

Heavy metals and arbuscular mycorrhizal (AM) fungi can alter the yield and chemical composition of volatile oil of sweet basil (<Emphasis Type="Italic">Ocimum basilicum</Emphasis> L.)

The effects of increasing levels of metals (10 and 20 mg of Cr kg^-1 and 25 and 50 mg of Cd, Pb, and Ni kg^-1 soil) and arbuscular mycorrhizal (AM) fungi Glomus intraradices on the yield, chemical composition of volatile oil, and metal accumulation in sweet basil (Ocimum basilicum L.) were investigated in a pot experiment. The shoot yield, content of essential oil, and root yield of sweet basil were increased by the application of low dose of Cd, Pb, and Ni as compared to control. The application of high level of metals had deleterious effect on the yield. In soil with low dose of metal applied, AM fungi inoculation significantly enhanced the metal concentration in shoots and had adverse effect on the yield, whereas in soil with high dose of metal applied, AM fungal inoculation reduced the metal concentration in shoot and had beneficial effect on the yield. The content of linalool in basil oil was decreased and that of methyl chavicol was increased by the application of Cr, Cd, and Pb in soil as compared to control. Similarly, the level of linalool and methyl chavicol was decreased and that of methyl eugenol was increased by the application of Ni as compared to control. However, AM fungal inoculation led to maintain the content of linalool, methyl chavicol, and methyl eugenol in volatile oil, which were either increased or decreased by the application of metals. We conclude that the AM–sweet basil symbiosis could be used as a novel approach to enhance the yield and maintain the quality of volatile oil of sweet basil under metal-contaminated soils.     

Cellulase activity in rohu fingerlings

The activity of cellulase was determined in the intestine of rohu, Labeo rohita, fingerlings fed on separate dietary formulations incorporating Leucaena leaf meal and synthetic cellulose at 20% level in proportional replacement of the ingredients from the fish-meal-based reference diet. Three more replicate experimental diets were prepared by incorporating 1% tetra-cycline, a broad-spectrum antibiotic, into the former three dietary formulations so as to circumvent the action of microflora in digestive function. Cellulase activity was found to be highest in fish fed on the cellulose incorporated diet, followed by those maintained on the plant-protein-based and reference diets, respectively. A diet-dependent variation in cellulase activity was apparent. However, a sharp decline in the level of cellulase activity was observed in the fish fed diets containing tetracycline, which is supposed to have destroyed all the gut microflora. The microbial culture of intestinal and hepatopancreatic extracts also confirmed the absence of microflora in the fish fed tetracycline-compounded diets. The study indicates that cellulase activity in rohu is largely contributed by the intestinal microflora, while the reduced activity recorded in the fish reared on antibiotic-compounded diets may be due to the presence of some other source of cellulase secretion apart from cellulolytic microbial action. The information generated from the present investigation might contribute towards better feed formulation for carp at low cost, incorporating plant-based feed ingredients. © Rapid Science Ltd. 1998     

Influence of strain, dose of virus, and age at inoculation on subgroup J avian leukosis virus persistence, antibody response, and oncogenicity in commercial meat-type chickens

The effects of viral strain, viral dose, and age of bird at inoculation on subgroup J avian leukosis virus (ALV J) persistence, neutralizing antibody (VNAb) response, and tumors were studied in commercial meat-type chickens. Chickens were inoculated on the fifth day of embryonation (5 ED) or on day of hatch (DOH) with either 100 or 10,000 50% tissue-culture infective dose (TCID50) of one of three ALV J strains, namely ADOL Hcl, ADOL 6803, or ADOL 4817. At 1, 3, 7, 11, 15, 19, 23, 27, and 32 wk posthatch, chickens were examined for ALV J viremia and VNAb against the inoculated strain of ALV J. A high incidence (83%-100%) of ALV J persistence was observed in all treatment groups. Development of VNAb did not always lead to viremia-free status; even though 18% of the chickens developed VNAb, only 4% were able to clear viremia. The viral strain, dose, and age of bird at inoculation seemed to have an effect on the incidence of VNAb; however, the differences were statistically significant in only some treatment groups. Chickens infected with ADOL 6803 had higher incidence of VNAb than chickens infected with ADOL Hc1 and ADOL 4817 (P < 0.05 in groups 5 ED at 100 TCID50 and DOH at 10,000 TCID50). There was a trend in all groups inoculated with 100 TCID50 to have higher incidence of VNAb than that of groups inoculated with 10,000 TCID50 (ADOL 6803 at 5 ED and ADOL 4817 at DOH [P < 0.05]; ADOL Hc1 at DOH [P < 0.08]). In most treatment groups (ADOL Hc1 at 100 and 10,000 TCID50, ADOL 6803 at 10,000 TCID50, and ADOL 4817 at 100 TCID50), chickens inoculated at DOH had higher incidence of VNAb than that of chickens inoculated at 5 ED (ADOL 6803 at 10,000 TCID50 [P < 0.05], ADOL Hc1 at 100 TCID50 [P < 0.08]). Incidence of ALV J-induced tumors and tumor spectrum were influenced by viral strain, age at inoculation, and VNAb response.     

The perfect ocean for drought

The 1998-2002 droughts spanning the United States, southern Europe, and Southwest Asia were linked through a common oceanic influence. Cold sea surface temperatures (SSTs) in the eastern tropical Pacific and warm SSTs in the western tropical Pacific and Indian oceans were remarkably persistent during this period. Climate models show that the climate signals forced separately by these regions acted synergistically, each contributing to widespread mid-latitude drying: an ideal scenario for spatially expansive, synchronized drought. The warmth of the Indian and west Pacific oceans was unprecedented and consistent with greenhouse gas forcing. Some implications are drawn for future drought.     

The role of phenols in potato tuber resistance against soft rot byErwinia carotovora ssp.carotovora

Summary Increasing doses of nitrogenous fertilizer increased storage rots in six potato cultivars of which cvs Kufri Sindhuri and Kufri Lalima rotted less and were found to contain high amounts of total phenols compared to the more susceptible cultivars Kufri Jyoti and Kufri Badshah. Nine phenolic acids were identified in the peel and the pulp of tubers and four of these and of other phenolic extracts from tubers suppressed the growth ofErwinia carotovora ssp.carotovora. Research Publication No. 5811, Experiment Station, G.B.P.U.A. & T., Pantnagar 263 145, India.     

Development of somaclonal variants of wheat (Triticum aestivum L.) for yield traits and disease resistance suitable for heat stressed and zero-till conditions

In a substantial rice–wheat cropping system area of South Asia, wheat sowing often gets too delayed and exposed to terminal heat stress. Therefore, farmers prefer varieties that are able to perform well under a short growing period. Tissue culturally regenerated plants of wheat variety cv. HUW 234, the most widely cultivated variety of North Eastern Plain Zone (NEPZ) of India were screened using immature embryo as explant. Days to heading and maturity, yield and other yield components and resistance to leaf rust and spot blotch were evaluated. A few somaclones in R₃ and R₄ generations displayed significant earliness for days to heading and maturity, improved yield traits and resistance to leaf rust and spot blotch diseases. The superior performance of two of the variants was confirmed in the R₅ generation in 3 years of testing under two dates of conventional and zero-till sowing. Stability analysis also suggested superiority of the two somaclones across 12 environments. This appeared to confirm the possibility of obtaining useful somaclonal variants of wheat for very late sown as well as zero-till managed agriculture. The superior performing somaclones can be used as parents in the ongoing breeding programmes targeting late sown wheat in South Asia exposed to terminal heat stress.     

Assessment of genetic diversity,population structure and phytochemical variations in Polygonatum cirrhifolium (Wall.) Royle: an endangered medicinal herb

Genetic Resources and Crop Evolution - Polygonatum cirrhifolium (Wall.) Royle is an important medicinal herb of the family Asparagaceae used to cure several ailments. The rhizome of the species...     

Microclimate modifications,growth and yield of intercrops under Hardwickia binata Roxb. based agroforestry system

An experiment was conducted by planting Hardwickia binata Roxb. at 200, 400 and 800 trees ha^???1, intercrops viz., Brassica campestris (mustard) and Glycine max (soybean) were sown from the second year onwards in winter and summer respectively at the National Research Centre for Agroforestry, Jhansi, U.P., India with the objectives of evaluating agrosilvicultural potential of the system and to study the effect of tree densities on ecophysiology of understorey crops. Tree growth was affected by both density and intercrop in the initial years of growth. Photosynthetic photon flux density (PPFD) available to the intercrops reduced with increasing densities. Transpiration rate and stomatal conductance in intercrops decreased due to the presence of trees. No significant changes in leaf temperature were observed till the fifth year of the growing season. Yield was significantly higher in pure crop in comparison with all the densities in mustard. Soybean yield under 200 trees ha^???1 was comparable to that of the pure crop. Trees at the density of 200 trees ha^???1 provided a conducive microenvironment to the intercrops.     

HPTLC analysis of guggulsterone isomers in Commiphora wightii (Arn.) Bhandari: an endangered oleo-gum resin species heading towards extinction

The oleo-gum resin of Commiphora wightii (Arn.) Bhandari, a pharmacologically important balsamiferous woody shrub, has been used in treating various ailments and disorders since ancient times (2000 B.C.) due to the presence of steroidal compound guggulsterone. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering and anti-cancerous activities. Further, guggul has been approved as food supplement by US-FDA as well as Council of Europe. Indiscriminate harvest of C. wightii from wild with negligible conservation efforts has lead to its inclusion in IUCN assemblage of endangered plant species. For identification of high guggulsterone yielding ecotypes of C. wightii, using high-performance thin-layer chromatographic (HPTLC) analysis, stem samples were collected from 50 plants from eleven locations in arid tracts of Haryana, Gujarat and Rajasthan. Dried, powdered material was subjected to extraction with petroleum ether using soxhlet apparatus. Samples were spotted on precoated activated silica plates (60F-254) and were developed using toluene–acetone (9:1 v/v) as mobile phase. The analysis was carried out in the absorbance mode at 250 nm using HPTLC scanner. The regression analysis data for the calibration plots for E and Z guggulsterone showed good linear relationship with R² = 1 and 0.9897, respectively. Highest concentration of guggulsterone E (284 μg/g dry wt) was found in the accession collected from Palana, Bikaner whereas highest guggulsterone Z concentration (89.5 μg/g dry wt) was found in the accession collected from CAZRI, Jodhpur.