Serological studies on leptospirosis in cattle in east central Alabama.

Serological surveys of leptospiral antibodies in cattle were carried out in Macon and the surrounding counties of East Central Alabama. A total of 286 bovine serum samples were screened for the presence of antibodies against live antigens from twelve pathogenic leptospiral serotypes using a microscopic agglutination test. The most frequently encountered serotypes were Leptospira hardjo (47%), Leptospira wolffi (34%), Leptospira canicola (12%), Leptospira pomona (10%) and Leptospira ballum (10%). Leptospira autumnalis, Leptospira grippotyphosa, Leptospira icterohemorrhagiae, Leptospira pyrogenes and Leptospira tarassovi were observed in less than 5% of the samples.     

Bovine Normal and Abnormal Reproductive and Endocrine Functions during the Postpartum Period: A Review

The results of numerous studies on postpartum uterine involution, ovarian activity and endocrinological changes before, during and after normal and abnormal parturitions, have been reviewed in this article. Most studies have shown that abnormal parturition is the main factor which delays completion of uterine involution and occurrence of the first estrous cycle post partum. The reviewed reports also indicated that any interference (corticosteroid injection, overiectomy, etc.) with normal synchronized hormonal changes of parturition can increase the incidence of retained fetal membrane. Reports on the use of hormonal treatments and their effects on the elimination of bacterial infection, rate of uterine involution and the resumption of ovulation activity are conflicting. It is suggested that the use of natural substances such as lipopolysaccharide of E. coli, serum or hyperimmune serum, extracts of poly morphonuclear leucocytes and/or macrophage-granulocyte Colony Stimulating Factor as treatments of postpartum uterine infection may play an important role in the completion of uterine involution and the commencement of estrous cycle .     

Assessing impacts of climatic variations on foodgrain prpduction in Bangladesh

A simulation study was conducted to assess the vulnerability of foodgrain production in Bangladesh to potential climate change. Simulation runs were made for high yield varieties office for Aus (March-August), Aman (July-November), and Boro (February-July), the traditional growing seasons, using the CERES-Rice model. Simulation runs were made for wheat, which is grown from November through March, using the CERES-Wheat model. Three scenarios (baseline, Canadian Climate Centre Model, and Geophysical Fluid Dynamics Laboratory) and sensitivity analyses for temperature increases of 2 and 4°C at three levels of CO₂ (330, 580, and 660 ppm) were used. In the simulation, increased CO₂ levels increased rice yields over baseline, and considerable spatial and temporal variations were noted. Higher temperatures reduced the yields in almost all study locations and in all seasons, and it was particularly pronounced with a 4°C increase. The detrimental effect of temperature rise was observed even with increased CO₂ levels. Wheat yields increased with increased CO₂ level in all three locations. The adverse effects of increased temperature were more pronounced for wheat than for rice at all levels of increased CO₂. In the scenarios of the Canadian Climate Centre Model and Geophysical Fluid Dynamics Laboratory, both rice and wheat yields were decreased (35% and 31 %, respectively) over baseline in all seasons, especially in the Aus season, and in all locations. The adverse effects of the climate under the Geophysical Fluid Dynamics Laboratory scenario were more pronounced for wheat that for rice. The greatest reductions in aggregated production for both crops were noted at 330 PPM CO₂ with a 4°C temperature rise. The greatest increases in aggregated production for rice and wheat were observed at a 660 ppm CO₂ with no temperature increase.     

Trypsin-sensitive plasmodia in the liver of post-infection rats and rhesus monkeys

Kupffer cells from the liver and erythrocytes from peripheral blood were collected at the post-patent period from albino rats infected earlier with Plasmodium berghei and rhesus monkeys infected earlier with P. cynomolgi var. bastianelli or P. knowlesi. The cells were subinoculated into individual normal recipients. These recipients subsequently showed parasitaemia in their circulation. The parasites present in Kupffer cell preparations were found to be sensitive to trypsin treatment, while those in erythrocytes were found to be resistant to trypsin treatment. This differential sensitivity of parasites to trypsin was observed in all the three species of plasmodia studied so far.     

Weed growth,herbicide efficacy,and rice productivity in dry seeded paddy field under different wheat stubble management methods

To ascertain the influence of wheat stubble management options and chemical weed control methods on weed growth and productivity of dry direct-seeded fine rice, a two years' field study was undertaken at the Agronomic Research Farm, University of Agriculture, Faisalabad, Pakistan in 2013 and 2014. Different wheat stubble management methods, viz., incorporation, burning and retention were executed during seed-bed preparation. While, herbicide treatments comprised of a weed check, weed free, pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl, and bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl. Results revealed that weed control efficacy of both herbicide treatments ranged from 84 to 94%. Herbicide treatments significantly reduced weed density(88–90%) and dry weight(86–88%), while improved the rice growth attributes compared with weed check. Application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention recorded 226 and 273% increase in kernel yield over weedy check in 2013 and 2014, respectively. In stubble incorporation, pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl was more effective in increasing(256–293%) rice yields over weedy check. Among different treatment combinations, the maximum net benefits(1 397.49~(–1) 472.22 USD ha~(–1)), net returns(636–700 USD ha~(–1)), benefit cost ratio(1.77~(–1).83) and marginal rate of return(2 187–2 330%) were recorded with the application of bispyribac sodium followed by fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention. In crux, application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention is efficient approach to control weeds, and get maximum rice productivity and net economic returns under dry seeded system.     

Response of cotton genotypes to planting date and plant spacing

Cotton growers face a problem of low cotton yield in late planting (after sunflower and maize). The objective of our study was to determine the effects of planting date, plant spacing (plant density), and genotypes on seed cotton yield and its components, ginning outturn (GOT%), and fiber quality traits (fiber length and fiber fineness). Five planting dates (May 1, May 15, May 30, June 15, and June 30), three plant spacings (15, 30, and 45 cm), and three cotton genotypes (CRS-6070, CRS-738, and CIM-496) were evaluated for seed cotton yield with its components and fiber quality traits. The results showed that monopodial branches/plant, sympodial branches/plant, number of bolls/plant, and seed cotton yield differed significantly among different planting dates, plant spacing, and genotypes. While the boll weight was significantly different among genotypes only. GOT%, fiber length, and fiber fineness were different significantly among planting time and cotton genotypes, which were not significantly affected by plant spacing. Cotton grown in early planting dates had higher seed cotton yield (4874 and 4653 kg/hm²) at the highest plant spacing (45 cm). While late sown cotton (June 15 onward) gave higher seed cotton yields (2068 and 1889 kg/hm²) at the lowest plant spacing (15 cm). GOT%, fiber length, and fiber fineness improved significantly in late planting and not affected from plant spacing. From our present study, it is concluded that high seed cotton yield can be achieved at high plant spacing in early planting while at low plant spacing in late planting.     

Characterization of mutants of the chestnut blight fungus (<Emphasis Type="Italic">Cryphonectria parasitica</Emphasis>) with unusual hypovirus symptoms

The type virus of the family Hypoviridae, Cryphonectria hypovirus 1 strain EP713 (CHV1-EP713), infects Cryphonectria parasitica, the filamentous causal fungus of chestnut blight, and reduces its virulence. This pathosystem serves as a model to study fungus-mycovirus interactions. We previously developed a genetic screening protocol for host factors associated with symptom induction by CHV1-EP713 and its mutants. In the procedure the standard field fungal isolate EP155 was transformed by cDNA from a mild hypovirus mutant Cys(72), launching virus infection, and mutagenized by random plasmid insertion with pHygR conferring hygromycin resistance. We now report an extension of the study to characterize different mutant strains, with different phenotypes than their parental strain TCys(72)-1. TCys(72)-1 is moderately reduced in pigmentation and sporulation compared to the uninfected wild-type strain EP155. Mutants sfb1, sfb2 and k202 were characterized biologically and molecularly in comparison to the previously isolated mutant (namA) and the parental strain. These mutants harbored one (sfb1) or more copies (sfb2 and k202) of the mutagenic plasmid, pHygR. The three mutants had similar biological attributes; that is, vegetative growth rate, conidiation and virulence (assay on apples) was reduced on potato dextrose agar media, relative to the parental strain and pigmentation was the same or slightly increased. Interestingly, viral dsRNA accumulation levels were apparently unaltered in these mutants. The screening method was efficient for mining fungal mutants with unusual hypovirus symptoms. Further, characterization of the mutants provides interesting insights into symptom induction by the hypovirus.