Land degradation mapping by remote sensing in the arid region of India

Abstract. In arid regions of India, cultivation of marginal areas and overgrazing of pastures have resulted in degradation of land. Accelerated wind erosion on sandy surfaces and water erosion on the shallow soils of piedmont areas are both common. Landsat Thematic Mapper sub-scenes have been used to map the type, extent and degree of degradation. In an area of over 5000 km², 42% was affected by wind erosion and 50% by accelerated water erosion. A quarter of the whole area needs urgent attention for soil conservation.     

Genetic variability and diversity for protein and calcium contents in finger millet (Eleusine coracana (L.) Gaertn) in relation to grain color

Analysis of 36 genotypes of finger millet ( Eleusine coracana (L.) Gaertn) with varying seed colors revealed a wide range of protein and calcium contents. White seeded genotypes had higher protein contents, while brown seeded types had a wide range of values. The brown seeded genotype GE 2500 had the highest protein content. Although protein content had significant negative association with calcium content, white seeded types had moderate levels of calcium. The genotypic coefficients of variability were moderate and high for protein and calcium, respectively. High heritability coupled with high genetic advance indicated their governance by additive gene action. A negative significant correlation was observed between protein content and grain yield. Mahalanobis D 2 analysis grouped the 36 genotypes into eight clusters. Clustering pattern failed to indicate any relationship between genetic diversity and geographic diversity. Based on genetic diversity and performance, the genotypes MS 1168, MS 174 and CO 13 were found to be suitable for use as parents in a hybridization program for improving yield; the genotypes MS 1168, MS 174 and MS 2869 for protein and Malawi 1915 and CO 11 for calcium. Protein and calcium contents contributed less to genetic divergence.     

Antimicrobial activity of some Indian mosses

The present study was designed to evaluate the antimicrobial activity of ethanolic extracts of 15 Indian mosses. The antibacterial activity of ethanolic extracts was investigated against five G(+) and six G(-) bacterial strains. Antimycotic activity was assayed against 8 fungi. Sphagnum junghuhnianum, Barbula javanica, Barbula arcuata, Brachythecium populeum, Brachythecium rutabulum, Mnium marginatum and Entodon cf rubicundus were found to be most active against all the organisms.     

Oral transmission of Trypanosoma evansi infection in dogs and mice

A successful attempt has been made to transmit T. evansi orally in dogs and mice by allowing them to feed on infected meat and blood. The infection status was determined by daily examination of blood smears and clinical manifestations of trypanosomiasis.     

Interleukin-2 and interleukin-10 gene expression in calves experimentally infected with Fasciola gigantica

The gene expression of interleukin-2 and interleukin-10 in calves with a primary infection of Fasciola gigantica was studied. Five calves were infected orally with a dose of 1000 viable metacercariae of F. gigantica and five calves served as uninfected control animals. Expression of two cytokine genes i.e. IL-2 and IL-10 (Th1 and Th2) was measured at 10, 30 and 75 days post-infection (PI) by real-time polymerase chain reaction with the double stranded DNA-binding dye SYBR Green. Interleukin-2 was not detected in the peripheral blood mononuclear cells (PBMCs) of infected or control animals at 10, 30 and 75 days PI, however, IL-10 was present in detectable levels in PBMCs of infected animals at 10, 30 and 75 days PI, with no expression of this cytokine in the control animals. With an increased expression of IL-10 and no expression of IL-2 cytokine gene, the present study suggests that F. gigantica infection in calves evoked Th2 immune response.     

Cytogenetics of tropical bulbous ornamentals. IX. Breeding systems in Zephyranthes

Summary Zephyranthes is a rather versatile genus and contains self-incompatible and self-compatible taxa coupled with positional barrier between stigma and anthers. The two may augment or run counter to each other. Furthermore, the genus also contains sexual and agamospermous species. The latter are often self-pollinated and pseudogamous. Z. sulphurea (2n=48) when pollinated with Z. candida (2n=40 and 41) has consistently given rise to seedlings with maternal chromosome number and morphology. Z. lancasteri and cv. 20 also behave similarly. This is a strong pointer for their being agamospermous, although a final proof will come from an embryological study. The intraspecific polymorphism within agamospermous taxa in the genus may be the result of autosegregation. On the other hand, the crosses involving sexual species like Z. candida (2n=41) as the female parent have generated a large heterogeneous progeny ranging in chromosome number from 2n=33 to 48 depending upon the number in the male parent. Such versatility of the breeding system together with chromosomal repatterning, hybridization, polyploidy and vegetative multiplication/apomixis explains the origin and preservation of an astonishing range in chromosome numbers from 2n=18 to 96.     

Mentoring within the veterinary medical profession: veterinarians' experiences as proteges in mentoring relationships

Veterinary medicine professionals have recognized the importance of enhancing mentoring of students, as recruitment and retention of students have become prominent concerns. The purpose of the present study was to examine the form and degree of mentoring experienced by practicing veterinarians, as well as to seek to understand the factors that influence effective mentoring relationships. Data concerning their own experiences with mentoring relationships were gathered from practicing veterinarians. Results suggest that most practicing veterinarians had mentors and that the most frequent and effective mentors were initial employers, followed by teachers and advisors. Behaviors aimed at career development and socio-emotional support correlated highly with the perceived effectiveness of the relationship. Perceived similarity between the protege and the mentor also predicted effectiveness. These results are discussed as they relate to veterinary education.     

Agrobacterium-Mediated Transformation of Fusarium oxysporum: An Efficient Tool for Insertional Mutagenesis and Gene Transfer

ABSTRACT Agrobacterium tumefaciens-mediated transformation (ATMT) has long been used to transfer genes to a wide variety of plants and has also served as an efficient tool for insertional mutagenesis. In this paper, we report the construction of four novel binary vectors for fungal transformation and the optimization of an ATMT protocol for insertional mutagenesis, which permits an efficient genetic manipulation of Fusarium oxysporum and other phytopathogenic fungi to be achieved. Employing the binary vectors, carrying the bacterial hygromycin B phosphotrans-ferase gene (hph) under the control of the Aspergillus nidulans trpC promoter as a selectable marker, led to the production of 300 to 500 hygromycin B resistant transformants per 1 x 10(6) conidia of F. oxysporum, which is at least an order of magnitude higher than that previously accomplished. Transformation efficiency correlated strongly with the duration of cocultivation of fungal spores with Agrobacterium tumefaciens cells and significantly with the number of Agrobacteruium tumefaciens cells present during the cocultivation period (r = 0.996; n = 3; P < 0.01). All transformants tested remained mitotically stable, maintaining their hygromycin B resistance. Growing Agrobacterium tumefaciens cells in the presence of acetosyringone (AS) prior to cocultivation shortened the time required for the formation of transformants but decreased to 53% the percentage of transformants containing a single T-DNA insert per genome. This increased to over 80% when Agrobacterium tumefaciens cells grown in the absence of AS were used. There was no correlation between the average copy number of T-DNA per genome and the colony diameter of the transformants, the period of cocultivation or the quantity of Agrobacterium tumefaciens cells present during cocultivation. To isolate the host sequences flanking the inserted T-DNA, we employed a modified thermal asymmetric interlaced PCR (TAIL-PCR) technique. Utilizing just one arbitrary primer resulted in the successful amplification of desired products in 90% of those transformants analyzed. The insertion event appeared to be a random process with truncation of the inserted T-DNA, ranging from 1 to 14 bp in size, occurring on both the right and left border sequences. Considering the size and design of the vectors described here, coupled with the efficiency and flexibility of this ATMT protocol, it is suggested that ATMT should be regarded as a highly efficient alternative to other DNA transfer procedures in characterizing those genes important for the pathogenicity of F. oxysporum and potentially those of other fungal pathogens.     

Inheritance of β-carotene concentration in durum wheat (Triticum turgidum L. ssp. durum)

Despite being one of the important characteristics in determining pasta quality in durum wheat (Triticum turgidum ssp. durum), there is no direct report on inheritance of β-carotene concentration. The objectives of this study were to determine the inheritance of β-carotene concentration and the number of genes involved in six crosses of durum. For the cross PDW-233 (P₁) × Bhalegaon-4 (P₂), F₁, F₂, BCP₁ and BCP₂ populations were developed. For all other crosses, only the F₁ and F₂ populations were developed. β-carotene concentration was determined for all populations and parents of each cross grown at Hol, Maharastra, India. The cross PDW-233 × Bhalegaon-4 was also evaluated at Dharwad, Karnataka, India. Low β-carotene concentration was partially dominant in most of the crosses. Broad sense heritability was 67 and 91% at Dharwad and Hol, respectively, for the cross PDW-233 × Bhalegaon-4 and varied from 74 to 93% for the other five crosses indicating the presence of additive gene effects. The frequency distributions of the trait in the F₂ populations were not normal and were skewed towards the lower parent. Segregation of β-carotene concentration in the six F₂ populations indicated that at least two major genes and two or three minor genes with modifying effects govern the trait. Analysis of variance indicated that environment had comparatively little influence on the trait and this should allow for easy selection. The joint scaling test revealed additive × additive, additive × dominance and dominance × dominance epistatic interactions in the cross PDW-233 × Bhalegaon-4. These authors contributed equally.     

Genotyping safflower (Carthamus tinctorius) cultivars by DNA fingerprints

Summary Carthamus tinctorius (2n = 2x = 24) (family Asteraceae), commonly known as safflower, is widely cultivated in agricultural production systems of Asia, Europe, Australia and the Americas as a source of high-quality vegetable and industrial oil. India ranks first in the production of safflower oil. Fourteen cultivars, widely cultivated in various agro-climatic regions of India, have been fingerprinted by RAPD, ISSR, and AFLP markers utilizing 36, 21 primers, and 4 primer combinations, respectively. On an individual assay basis, AFLP has proven to be the best marker system as compared with the other two markers applied as assessed by high discriminating power (0.98), assay efficiency index (33.2), marker index (18.2), resolving power (40.62), and genotype index (0.856). Thirty-six RAPD and 21 SSR primers could differentiate a maximum of eight and four cultivars, respectively, whereas, two AFLP primer combinations could fingerprint all the 14 cultivars. To understand genetic relationships among these cultivars, Jaccard's similarity coefficient and UPGMA clustering algorithm were applied to the three marker data sets. Mean genetic similarities ranged from 0.689 (AFLP) to 0.952 (ISSR). Correlation coefficient comparisons between similarity matrices and co-phenetic matrices obtained with the three markers revealed that AFLP displayed no congruence vis-a-vis RAPD and ISSR data. However, strong correlation was observed between RAPD and ISSR marker systems. This paper reports the start of molecular biology programme targeting nuclear genome of safflower, a major world oilseed crop about whose genetics very little is known.