Effects of dietary inclusion of the beta-adrenergic agonist, salbutamol, on growth performance and whole-body composition of rohu Labeo rohita (Hamilton) fingerlings fed diets containing two protein levels

A 60-day feeding experiment was conducted in the laboratory to evaluate the effect of oral administration of the beta-adrenergic agonist (BAA), salbutamol, on growth, nutrient utilization and whole-body composition of rohu Labeo rohita (Hamilton) fingerlings (average weight 5.51 ± 0.07 g) acting as a repartitioning agent in intermediary metabolism and redistributing nutrients for muscle synthesis. Two diets (diets 30/0 and 40/0) were formulated containing 30% and 40% crude protein to serve as basal diets containing the same ingredient composition. Another four diets (diets 30/3, 30/6, 40/3 and 40/6) were prepared in the same way to contain either 3 or 6 mg kg⁻¹ BAA salbutamol at each protein level making the total of six experimental diets. Rohu fingerlings were fed with the experimental diets in three replicate treatments at a restricted feeding regime equivalent to 2% of body weight (BW) day⁻¹. A significant (P < 0.05) interaction effect was found between dietary protein level and BAA treatment. Dietary incorporation of BAA at both protein levels significantly (P < 0.05) increased growth and nutrient utilization in terms of weight gain (%), specific growth rate (SGR), feed:gain ratio (FGR) and protein efficiency ratio (PER). BAA treatment at the 6 mg kg⁻¹ concentration led to a 12% rise in growth with the 30% protein diet and a 6% rise with the 40% protein diet, above their respective controls (without BAA treatment). However, no significant differences were found by raising the BAA concentration from 3 to 6 mg kg⁻¹. The apparent digestibility values for protein, lipid and energy were only higher with the 30% protein diets containing BAA. At both protein levels tested, BAA exerted a significant (P < 0.05) positive influence on protein retention and a negative influence on lipid retention efficiency, although the differences between the 3 and 6 mg kg⁻¹ BAA diets were not significant. This indicated that BAA acted as a repartitioning agent in suppressing lipid deposition in favour of protein accretion. BAA induced significantly (P < 0.05) higher whole-body protein and lipid relative to the untreated groups. The condition factor improved significantly (P < 0.05) in the BAA-treated dietary groups. The fillet percentage displayed a direct correlation and the frame percentage a negative correlation with BAA concentration in the diets. The results indicate that the BAA, salbutamol, was effective in producing growth enhancement, improved body composition (higher protein and lower lipid accretion) and efficient nutrient utilization at the 3 mg kg⁻¹ dietary incorporation level and thus has a potential for application in formulated diets for the Indian major carp, rohu, under culture conditions.     

Molecular characterization of Citrus yellow mosaic badnavirus (CMBV) isolates revealed the presence of two distinct strains infecting citrus in India

Citrus yellow mosaic badnavirus (CMBV) is a non-enveloped, bacilliform DNA virus and the etiologic agent of yellow mosaic disease of citrus in India. The disease was initially reported from the southern parts of India and has now spread to other parts of the country. It is a serious disease of sweet orange (Citrus sinensis) in southern India, where it causes significant yield losses. During a recent survey of citrus groves in the Nagpur region, central India, characteristic mosaic symptoms were observed in mandarin orange (Citrus reticulata) and sweet orange. Virus transmission studies, electron microscopy, PCR amplification and sequencing of cloned PCR products from samples showing mosaic symptoms confirmed the presence of a badnavirus. The CMBV–Nagpur isolate could be transmitted to the Rangpur lime (C. limonia) and acid lime (Citrus aurantifolia) by graft inoculation. Sequence analysis of a segment of ORF-III region and intergenic region (IR) of the viral genome revealed that CMBV–Nagpur isolate formed a distinct clade along with some previously reported isolates that are known to infect acid lime and Rangpur lime. CMBV isolates that infect citrus species other than the acid lime and Rangpur lime formed a second clade. Based on the transmission studies and phylogenetic analyses, it was concluded that at least two strains of CMBV exist in India currently.     

Application of Statistical Tools for Data Analysis and Interpretation in Rice Plant Pathology

There has been a significant advancement in the application of statistical tools in plant pathology during the past four decades. These tools include multivariate analysis of disease dynamics involving principal component analysis, cluster analysis, factor analysis, pattern analysis, discriminant analysis, multivariate analysis of variance, correspondence analysis, canonical correlation analysis, redundancy analysis, genetic diversity analysis, and stability analysis, which involve in joint regression, additive main effects and multiplicative interactions, and genotype-by-environment interaction biplot analysis. The advanced statistical tools, such as non-parametric analysis of disease association, meta-analysis, Bayesian analysis, and decision theory, take an important place in analysis of disease dynamics. Disease forecasting methods by simulation models for plant diseases have a great potentiality in practical disease control strategies. Common mathematical tools such as monomolecular, exponential, logistic, Gompertz and linked differential equations take an important place in growth curve analysis of disease epidemics. The highly informative means of displaying a range of numerical data through construction of box and whisker plots has been suggested. The probable applications of recent advanced tools of linear and non-linear mixed models like the linear mixed model, generalized linear model, and generalized linear mixed models have been presented. The most recent technologies such as micro-array analysis, though cost effective, provide estimates of gene expressions for thousands of genes simultaneously and need attention by the molecular biologists. Some of these advanced tools can be well applied in different branches of rice research, including crop improvement, crop production, crop protection, social sciences as well as agricultural engineering. The rice research scientists should take advantage of these new opportunities adequately in adoption of the new highly potential advanced technologies while planning experimental designs, data collection, analysis and interpretation of their research data sets.     

Rates of decomposition and nutrient mineralization of leaf litter from different orchards under hot and dry sub-humid climate

Leaf litter decomposition is a critical step in nutrient cycling and providing nutrients to plants. Decomposition of dry matter, lignin, ligno-cellulose, cellulose and polyphenols was investigated in relation to nitrogen (N), phosphorus (P) and potassium (K) dynamics in leaf litter of mango, guava and litchi orchards under hot and dry sub-humid climate. Leaf litter of mango and guava decomposed more rapidly than that of litchi with decay constants of 3.22, 1.33 and 0.62 yr^-1, respectively. The leaf litter organic substances like polyphenol lost more rapidly followed by cellulose, lignin and ligno-cellulose throughout the period of decomposition. The N was released faster both in mango and guava with decay constant of 4.06 and 2.11 yr^-1, respectively. The release of K was faster in mango followed by guava and litchi with decay constant of 4.66, 3.18 and 1.63 yr^-1, respectively. The leaf litter decomposition was significantly positively correlated with soil fungal and bacterial biomass, rainfall and air temperature, while the leaf chemistry showed significant negative correlations in all the orchards. The results demonstrated that mango leaf litter was found to be the best followed by guava, and litchi in terms of N, P, and K return in less period of time.     

Coenzyme Q9 provides cardioprotection after converting into coenzyme Q10

Coenzyme Q10 (CoQ10) has been extensively studied as adjunctive therapy for ischemic heart disease, and its cardioprotective ability is well-established. The mitochondrial respiratory chain contains several coenzymes, including CoQ1, CoQ2, CoQ4, CoQ6, CoQ7, CoQ8, CoQ9, and CoQ10. It is not known whether other CoQs, especially CoQ9, is equally cardioprotective as CoQ10. The present study was designed to determine if CoQ 9 could protect guinea pig hearts from ischemia reperfusion injury. Guinea pigs were randomly divided into three groups: groups I and II were fed CoQ 9 and CoQ10, respectively, for 30 days while group III served as control. After 30 days, the guinea pigs were sacrificed and isolated hearts were perfused via working mode were subjected to 30 min ischemia followed by 2 h of reperfusion. Cardioprotection was assessed by evaluating left ventricular function, ventricular arrhythmias, myocardial infarct size, and cardiomyocyte apoptosis. Samples of hearts were examined for the presence of CoQ9 and CoQ10. The results demonstrated that both CoQ9 and CoQ10 were equally cardioprotective, as evidenced by their abilities to improve left ventricular performance and to reduce myocardial infarct size and cardiomyocyte apoptosis. High performance liquid chromatographic (HPLC) analysis revealed that a substantial portion of CoQ9 had been converted into CoQ10. The results indicate that CoQ9 by itself, or after being converted into CoQ10, reduced myocardial ischemia/reperfusion-induced injury.     

Effects of forcing,etiolation and indole butyric acid on rooting of cuttings of Artocarpus heterophyllus Lam.

Rooting of cuttings of jackfruit (Artocarpus heterophyllus Lam.) has been successfully induced through forcing of shoots, etiolation and application of indole butyric acid (IBA) under mist spray. Maximum rooting (84%) and maximum survival (50–75%) were obtained with the forced and etiolated shoots treated with 5000 mg/l IBA. The next best treatment was the forced and etiolated shoots treated with 10 000 mg/l IBA, which was somewhat similar to forced, non-etiolated shoots treated with 5000 mg/l IBA. In the control without IBA no success was obtained even under forcing and etiolation.     

Role of irrigation and mulch on yield, evapotranspiration rate and water use pattern of tomato (Lycopersicon esculentum L.)

Irrigation management strategy invites the quantification of crop response to irrigation frequencies. Conventionally, mulches increase the yield and water use efficiency (WUE) to a great extent by augmenting the water status in the root zone profile. A field study was carried out during the winter season (November-March) of 2003-2004 and 2004-2005 at the Central Research Farm of Bidhan Chandra Krishi Viswavidyalaya (Latitude 22°58′N, Longitude 88°31′E and altitude 9.75 m amsl), Gayeshpur, India, to evaluate the effect of irrigation frequencies and mulches on evapotranspiration rate from tomato crop field as well as leaf area index (LAI), fruit yield and WUE of the crop. The experiment was laid out in a split-plot design where three irrigation treatments {rainfed (RF); CPE₅₀ and CPE₂₅ where irrigation was given at 50 and 25 mm of cumulative pan evaporation (CPE)} were kept in the main plots and the subplots contained four mulch managements {no mulch (NM), rice straw mulch (RSM), white polyethylene mulch (WPM) and black polyethylene mulch (BPM)}. Under CPE₂₅, tomato crop recorded significantly higher leaf area index (LAI) over CPE₅₀ and rainfed condition. LAI value under BPM was 9-30% more over other mulches. Maximum variation of LAI among different treatments was recorded at 60 days after transplanting (DAT). Fruit yield under CPE₂₅ was 39.4 Mg ha⁻¹; a reduction of 7 and 30% has been obtained under CPE₅₀ and RF condition. The use of mulch increased 23-57% yield in comparison to NM condition. Actual evapotranspiration rate (ET_R) was 1.82 mm day⁻¹ under CPE₂₅ and declined by 15 and 31% under CPE₅₀ and RF condition, respectively. The variation of ET_R among different mulches became more prominent under maximum water stressed (RF) condition, whereas the variation was negligible under CPE₂₅ frequency. Irrespective of mulching WUE was highest under moderately wet (CPE₅₀) soil environment. Among different mulches, BPM was responsible for attaining the highest WUE value (25.1 kg m⁻³), which declined by 22, 21 and 39% under WPM, RSM and NM, respectively.