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61.
Mohamad Ali Fulazzaky Teng Wee Seong Mohd Idrus Mohd Masirin 《Water, air, and soil pollution》2010,205(1-4):63-77
Water quality degradation in the Selangor River will still be present in the years to come since pollutant loads from poultry farms, municipal wastewaters, and industrial wastewaters are not envisaged to be handled effectively. This will be facing the problems of water quality status to use for multiple purposes and to provide its aquatic environment continuously. The water quality evaluation system is used to assess the water quality condition in the river. This system distinguishes two categories of water condition i.e., the water quality index and water quality aptitude. The assessment of water quality for the Selangor River from nine stations along the main stream, which concludes that water has been highly polluted (index 5) immediately downstream of station 02 Selangor River before confluence with Kubu River due to high concentration of microorganisms and immediately downstream of station 06 Selangor River before confluence with Batang Kali River due to high concentrations of microorganisms and suspended particles, was verified. Mineral micropollutants were found to gradually pollute the stream water, ranging from the unpolluted water (index 1) in the upstream to the bad quality (index 4) in the downstream area. 相似文献
62.
In long-term field experiments on loamy sand and sandy loam, legumes (pea and lupine) stimulated microbial activity in the rhizosphere more than cereals (winter rye, winter wheat and spring barley), maize and oil flax. In the rhizosphere of winter wheat and maize, microbial activity and the bacteria species Pseudomonas , Agrobacterium and Xanthomonas were more stimulated by organic manuring than by mineral fertilization. A positive correlation between the stimulated bacteria species and the growth of young plants was found. Various mineral nitrogen applications had no influence on the rhizosphere microflora. The leghemoglobin content of pea nodules – an indicator of nitrogen fixation activity – was reduced by high nitrogen application in crop rotation. 相似文献
63.
Twenty-two buffalo bulls suffering from three different types of infertility were slaughtered and used for this study. Except for the reproductive system, no signs of localised or generalised disease were observed. Microbiological investigations were negative for brucellosis, vibriosis, mycoplasma and other non-specific microorganisms. Nine bulls with type 1 infertility had low bodyweights and underdevelopment of testes, accessory sex glands and endocrine glands. This picture suggests a total dysfunction of the pituitary-growth-gonadal axis. One bull of this type also showed bilateral epididymitis. Four out of 11 bulls with type 2 infertility had low bodyweights and most suffered from underdevelopment of testes, accessory sex glands and endocrine glands. Six bulls of this type had lesions of either epididymitis or orchitis or both. Two of these animals showed adhesions of periorchitis. One also showed seminal vesiculitis. In two bulls with type 3 infertility, bodyweights, reproductive organs and endocrine glands were normal. In later life, they yielded poor quality semen. Semen samples collected a few months before slaughter from nine bulls with type 2 and type 3 infertility were of poor quality and had higher percentages of abnormal spermatozoa in most cases. 相似文献
64.
Production of haploids, followed by chromosome doubling to produce doubled haploids (DH) represents the most rapid means of
achieving complete inbreeding. In order to improve the androgenetic responses and maximize the production of green regenerants
from selected plants of twenty-five triticale (× Triticosecale, Wittmack) populations (BC1F1, TC1F1, and F2) we used a uniform and optimal growth environment for anther donor plants within a greenhouse hydroponic system. Non-orthogonal
analysis of deviance showed highly significant differences (p < 0.001) among populations for both induction and regeneration. The overall induction response of the populations was very
high with a mean of 50.4 embryoids per 100 anthers plated. Among all tested-populations, M86-6068/TW179//EP80 (TC1F1) was the most responsive for both induction and regeneration which could be associated to its Triticum timopheevii cytoplasm. On the other hand, although populations 80465/II83-194 both as BC1F1 and F2 had a high level of induction response, only a few green plants were regenerated. These populations probably possess a partial
Secale montanum genome, which could be contributing to the low regeneration ability. In conclusion, the need for optimization of donor plant
growth conditions to effectively assess the androgenetic ability of individual populations/lines would be emphasized.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
65.
A plant with drastically reduced vigour was observed in a population of diploid barley (Hordeum vulgare) raised from seeds exposed to gamma radiation. Cytological studies revealed that the plant was nullisomic with 2n = 12. At meiosis, regular formation of 6 bivalents was observed. The plant was totally sterile and produced neither stainable pollen nor seed. 相似文献
66.
Haitham Sayed Gunter Backes Hamed Kayyal Amor Yahyaoui Salvatore Ceccarelli Stefania Grando Ahmad Jahoor Michael Baum 《Euphytica》2004,135(2):225-228
A partial genetic linkage map was constructed on 71 doubled-haploid lines derived from a cross between the barley lines Tadmor
and WI2291 with 181 molecular markers. The segregating population was used to detect markers linked to the gene Mlg conferring resistance to powdery mildew (Erysiphe graminis f. sp. hordei) and to genes for quantitative resistance to scald (Rhynchosporium secalis). The gene Mlg on chromosome 4H was flanked by two AFLP markers at a distance of 2.0 and 2.4 cM, respectively. QTLs for resistance to scald
were detected on chromosomes 2H and 3H. This association of molecular markers with qualitative and quantitative disease resistance
loci represents a valuable starting-point for marker-assisted selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
67.
68.
Sajad Majeed Zargar Bodo Raatz Humira Sonah MuslimaNazir Javid A. Bhat Zahoor Ahmad Dar Ganesh Kumar Agrawal Randeep Rakwal 《Journal of Crop Science and Biotechnology》2015,18(5):293-308
Recent advances in sequencing technology have brought several novel platforms for marker development and subsequent genotyping. The high-throughput and cost effective marker techniques have changed the entire scenario of marker applications. The huge genotypic data obtained with next generation sequencing (NGS) also demands analytical tools, statistical advances, and comprehensive understanding to cope with breeding applications. In the present review, we discussed different available marker techniques, their strengths, and limitations. Emphasis was given on software tools, analytical pipelines, workbenches, and online resources available for marker development. Comparison of SNP genotyping involving complexity reduction techniques like GBS, RRL, RAD, and array-based platforms were presented in a view to describe suitability for specific purposes. We found that genotyping by whole genome re-sequencing has great potential, and could be a routine application in the near future with continuously decreasing cost of sequencing. Microsatellites, still a valuable option for breeders, have also advanced with NGS. Here a catalogue of tools for microsatellite evaluation in short sequence reads was provided. The most common applications of molecular marker like QTL mapping, genome-wide association mapping (GWAS), and genomic selection were highlighted. The present review will be helpful for the effective utilization of available resources and for the planning of crop improvement programs employing molecular marker techniques. 相似文献
69.
Summary Eight grain pearl millet (2n=14) accessions were crossed as male to hexaploid spring wheat cv. Fukuho (2n=6x=42). An average of 80% wheat pistils showed pearl millet pollen tube entry in the ovules, compared to 56% in wheat x maize cv. Seneca 60 cross. Of the 15 embryos, obtained through in vitro immature seed culture from wheat x pearl millet crosses, 3 plantlets were produced and grown to maturity. These three were of the somatic chromosome constitution 2n=42, 21 and 22, respectively. Haploid wheat plant (2n=21) apparently originated from pearl millet chromosome elimination during embryogenesis. The 22 chromosome plant had retained a single pearl millet chromosome at tillering stage, but this chromosome was eliminated from pollen mother cells prior to and also during gamete formation. The significance and potential uses of this wide cross is discussed. 相似文献
70.
A wheat microsatellite locus, Xgwm 261, whose 192-bp allele closelylinked to the dwarfing gene Rht8, on chromosome 2D, was used toscreen 71 wheat cultivars from 13 countries to assess the variation at thislocus. Screening of this wheat collection showed that a 165-bp allele anda 174-bp allele were the most frequent. None of the New Zealand cultivarspossessed a 192-bp allele specific to Rht8, while only one cultivarfrom the US produced this important allele. The frequency of a 192-bpallele among these wheat cultivars was 5.63%. The highest allelefrequency was observed for a 174-bp fragment (52.11%) followed by a165-bp fragment (26.76%). The only durum wheat `Cham 1', did notshow any amplification due to the absence of D genome. Four new novelalleles, 180-bp, 198-bp, 200-bp and 204-bp present in the US and NewZealand wheat cultivars are reported. 相似文献