Antibiotic residues in goats milk following intramammary treatment

Two lactational intramammary antibiotic preparations (cloxacillin and oxytetracycline) were each used to treat eight goats by intramammary infusion in one half. The rate of release of the antibiotics was monitored by a diffusion assay based on the sensitive organism Bacillus stearothermophilus var. calidolactis. Cloxacillin was still detectable 156 hours after the final treatment while oxytetracycline was undetectable 108 hours following treatment. A small but significant amount of antibiotic was translocated between treated and untreated halves of the udder in both cases.     

Phytosanitary importance of Heterodera glycines for South-east Asian countries

Heterodera glycines is not known to occur in South-east Asian countries except in Indonesia. Specific surveys carried out recently in central India indicate absence of the nematode. The region has a large area under cultivation of soybean, and also other crop and wild hosts. H. glycines causes annual yield losses of about half a million metric tons in 10 major soybean-growing countries. Asia has to import half its demand of soybeans, mainly from North America and Brazil, where H. glycines occurs. Spread is mainly through soil mixed with seeds, or by spillage of grain. A preliminary pest risk analysis suggests that the South-east Asian region is suitable for the introduction and spread of H. glycines . Management practices are suggested to delay its introduction.     

Surveillance and monitoring for plant parasitic nematodes – a challenge

Surveillance of pests is an important activity for (a) early detection and prevention of spread of indigenous and exotic pests, (b) delimiting pest distribution, (c) searching for pest free areas for meeting the requirements of national and international trade and (d) to achieve effective management of pests that affect crop production. Recent developments on these topics are reviewed with special reference to plant parasitic nematodes in India.     

Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants

Background

Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed.

Results

Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO₃ (1.0), and MgSO₄ (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained.

Conclusions

The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.     

Lagenidium callinectes (Couch, 1942) infection and its control in cultured larval Indian tiger prawn, Penaeus monodon Fabricius

A mycosis in larval tiger prawn, Penaeus monodon Fabricius, is described for the first time from India. The hyphae of Lagenidium callinectes are contorted, irregularly branched, sparingly septate, and contain a cell wall and membrane, vacuoles, mito chondria, ribosomes, small and large vesicles, and Woronin bodies. The spores occur singly or in pairs. The fungal mycelium may either invade and embed itself in the tissues, or alternatively, replace all the muscle tissues of the infected larval P. monodon. Fungus infected, untreated populations of nauplii, zoea and myksis exhibited mortalities of 5.33 ± 0.55%, 24.68 ± 4.58% and 47.89 ± 0.27%, respectively. A 0.5 ppm treatment with trifluralin significantly reduced the mortality of infected larval populations (i.e. 1.1% nauplii, 3.28% zoea and 5.21% myksis mortality). Lagenidium sp. exhibited growth in potato dextrose agar medium and in Sabouraud's agar at 28 °C.     

Effect of tillage and mode of straw mulch application on soil erosion in the submontaneous tract of Punjab, India

The submontaneous tract of Punjab comprising 10% of the state, is prone to soil erosion by water. Soils of the area are coarse in texture, low in organic matter and poor in fertility. High intensity rains during the monsoon season result in fertile topsoil removal. There is an urgent need to control soil erosion in this region so as to improve soil productivity. A field study was conducted to estimate the effect of tillage and different modes of mulch application on soil erosion losses. Treatments comprised two levels of tillage, viz. minimum (T_m) and conventional (T_c) in the main plots and five modes of straw mulch application, viz. mulch spread over whole plot (M_w), mulch spread on lower one-third of plot (M_1/3), mulch applied in strips (M_s), vertical mulching (M_v) and unmulched control (M_o), in subplots in a replicated split plot design. Rate of mulch application was 6 t ha⁻¹ in all modes. Compared with M_o, M_w reduced runoff by 33%. Runoff and soil loss were 5 and 40% higher under T_c than under T_m. Though other modes of straw mulch application (M_1/3, M_s and M_v) controlled soil loss better than M_o, their effectiveness was less than M_w. T_m was more effective in conserving soil moisture than T_c. Compared with M_o, M_w had 3–7% higher soil moisture content in the 0–30 cm soil depth under T_m. Minimum soil temperature of the surface layer was 1.4–2.4 °C lower under M_w than under M_o. Straw mulching reduced maximum soil temperature and helped in conserving soil moisture. Minimum tillage coupled with M_w was highly effective in reducing soil erosion losses, decreasing soil temperature and increasing moisture content by providing maximum surface cover.     

Tracks of cosmic rays in plastics

Cosmic ray nuclei have been observed with the use of plastic trackdetecting solids in satellites and high-altitude balloon flights. Nuclear emulsions in the stacks of plastic sheets allowed the positive identification of cosmic raynuclei as light as nitrogen. The most striking new information was the failure to observe relativistic iron nuclei, a result which has led to an advance in the understanding of track registration criteria.     

Micrometeorite craters discovered on chondrule-like objects from kapoeta meteorite

Craters attributable to hypervelocity impacts of micrometeorites have been discovered on rare chondrule-like objects from the gas-rich meteorite Kapoeta. These chondrule-like objects, probably generated by impacts themselves, provide further evidence for the regolith origin of Kapoeta. The micrometeorite flux at the time of formation of the meteorites was probably an order of magnitude higher than the present flux, but the solar luminosity could not have been higher than 1.7 times its present value.     

Screening and selecting novel AM fungi and Azotobacter strain for inoculating apple under soil solarization and chemical disinfestation with mulch practices for sustainable nursery management

The objective of this study is to investigate the response of screening, and selection of novel indigenous AM fungal species and Azotobacter chroococcum strains for inoculating apple under different soil disinfestations and moisture conservation mulch practices for sustainable nursery management. Two local AM fungal species namely, Glomus fasciculatum (Thaxter sensu Gerdemann) and Glomus mosseae (Nicol. & Gerd.), and two strains of A. chroococcum viz., A. chroococcum strain-I (AZ₁) and A. chroococcum strain-II (AZ₂) were inoculated at nursery stage under soil solarization, chemical disinfestation and natural soil conditions at four different mulch materials namely, black plastic mulch (BPM), and organic mulches, i.e. grass mulch (GM); cover crops (CC); green manuring + clean cultivation (Gm + Cc). The comparative performance of the seedlings on the impact of local AM species and A. chroococcum strains on growth characteristics, microbial population, root colonization and leaf nutrient status was evaluated. The inoculation of seedlings to G. fasciculatum and AZ₁ increased all growth characteristics (plant height, stem diameter, leaf area and total root length), microbial consortium of the rhizosphere soil and leaf N, P, K and Zn content in all those plots where soil solarization and black plastic mulching was used followed by chemical disinfestations and natural soil conditions at all other mulch types used. These findings suggested that the soil inoculation of G. fasciculatum and AZ₁ strain to seeds and/or the saplings under soil solarization with black plastic mulch attained a desirable plant height and become ready for grafting which however saved a period of 1 year for nursery management compared to traditional nursery raising practice, and thus, it may be a viable and feasible approach to maintain soil productivity under nutrient limited soils for sustainable apple nursery production under temperate rain-fed conditions.     

Genetic Diversity for Morphological and Quality Traits in Quinoa(<Emphasis Type="Italic">Chenopodium quinoa</Emphasis> Willd.) Germplasm

Twenty nine germplasm lines of Chenopodium quinoa and two of Chenopodium berlandieri subsp. nuttalliae were evaluated for 12 morphological and 7 quality traits for two test seasons. The 19 traits were analyzed for cluster and principal component analysis. The first four PCs contributed 78.70 % of the variability among the germplasm lines. The first PC accounted for 39.5% of the variation and had inflorescence/plant, plant height and stem diameter as the traits with largest coefficients, all with positive sign. The characters with greatest positive weight on PC₂ were days to maturity (0.309), inflorescence length (0.260) and branches/plant. All the germplasm lines were grouped into six clusters based on average linkage method. Cluster III had high values for seed yield and most of the quality traits but showed a small seed size. The dendrogram separated the two lines of C. berlandieri subsp. nuttalliae from the quinoa lines.