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101.
William J. Aspden Alexandra Rao Katherine Rose Paul T. Scott Iain J. Clarke Timothy E. Trigg John Walsh Michael J. D'Occhio 《Domestic animal endocrinology》1997,14(6)
Anterior pituitary gland contents of LH and LHß- and α-subunit mRNAs, and circulating concentrations of LH and testosterone, were determined in bulls treated with the LH-releasing hormone (LHRH) agonist deslorelin. Brahman (Bos indicus) bulls (14-month-old) were allocated to two groups and received the following: Control (n = 5), no treatment; Deslorelin (n = 4), four deslorelin implants (approximately 200 μg total deslorelin/day) for 36 d. Plasma concentrations of LH were higher in bulls treated with deslorelin on Day 1, had returned to typical levels by Day 8, and did not differ for control bulls and bulls treated with deslorelin from Day 8 to Day 29. Pituitary content of LH on Day 36 was reduced (P < 0.001) in bulls treated with deslorelin (33 ± 4 ng/mg) compared with control bulls (553 ± 142 ng/mg). Relative pituitary content of LHß-subunit mRNA was also reduced on Day 36 in bulls treated with deslorelin (Control, 0.65 ± 0.10; Deslorelin, 0.22 ± 0.04; P = 0.003). However, α-subunit mRNA relative content did not differ (Control, 0.73 ± 0.15; Deslorelin, 1.06 ± 0.12; P > 0.05). Plasma concentrations of testosterone were increased over the period of the experiment in the bulls treated with deslorelin compared with control bulls. This is the first demonstration of reduced pituitary content of LHß-subunit mRNA and LH, and unaltered content of α-subunit mRNA, in bulls treated with LHRH agonist. This was associated with apparently typical plasma concentrations of LH and elevated plasma testosterone. The anterior pituitary in bulls treated with LHRH agonist, therefore, undergoes classical desensitization and downregulation, but plasma LH and testosterone are not suppressed. 相似文献
102.
Inheritance and linkage relationships of pearl millet seed esterase isozymes were studied using; polyacrylamide dise: gel electrophoresis and α-naphthyl acetate as substrate. The Zone of enzyme activity was resolved into five bands. The presence of a band showed complete dominance over its absence. Each one of the bands (1 to 4) was under the control of a single gene. Band five was found to be controlled by three independent loci with duplicate gent action Loci for Est1, Est3 and Est4 Were found to be linked. Est2 Was independent of this linkage group. 相似文献
103.
Cajanus reticulatus var. grandifolius, endemic to Australia and a wild relative of the cultivated species, C. cajan, was successfully crossed with the latter as the female parent. The major wild species characters such as persistent stipules,
long pod hairs, pod shattering, brown seeds with grey speckles, and presence of seed strophiole were dominant in the hybrid.
For growth and branching habit, and leaflet, flower, pod, and seed size, the hybrid was intermediate between the parents.
The meiotic cells of the hybrid were found to have quadrivalents, trivalents, univalents,and showed reduced chromosome pairing
as revealed by the increased number of rod bivalents per cell at metaphase-I, and stickiness and precocious movement of chromosomes
to poles in the second division. In comparison to the parents, the hybrid had fewer pods and seeds. However,these anomalies
in the interspecific hybrid are not significant enough to preclude the gene transfer from C. reticulatus to the cultivated species through a sexual route.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
104.
Mitochondrial DNA from two pairs of cytoplasmic male-sterile (cms) and maintainer lines of pearl millet was investigated by restriction-enzyme analysis and Southern-blot hybridization using three mitochondrial gene probes. Each pair of male-sterile and maintainer lines was of a different nuclear origin. The objective was to distinguish differences in the DNA base-sequence organization of the mitochondrial genomes of cms and maintainer lines from the two sources. Restriction-enzyme analysis revealed differences between the different cms and maintainer lines. Southern-blot hybridization experiments using cloned mitochondrial gene probes further distinguished differences between different lines. It is expected that the restriction-fragment-length polymorphisms revealed in the Southern-blot-hybridization experiments will be useful in distinguishing and classifying cms and maintainer lines obtained from different nuclear backgrounds. 相似文献
105.
肥料用量及施用方法对烤烟漂浮育苗烟苗素质的影响 总被引:5,自引:0,他引:5
采用小拱棚vaulted shed进行烤烟virginal tobacco漂浮育苗试验,以烤烟育苗肥(N 14.76%P2O57.33%、K2O 18.66%)用量及施用方法为参试因子,从出苗率emergence rate和成活率,烟苗的主要农艺性状、干物质积累量accumulation、各部位营养元素含量等方面进行探讨研究,结果表明,烤烟漂浮育苗施肥量以0.9kg/池(以可放入34个长66cm、宽34cm、高5cm的育苗盘的育苗池计)、并采用出苗期施60%和大十字期施40%的两次施肥方法的处理,其烟苗N、P、K、Ca的吸收量absorption amount,根部最高,茎部较高,而叶部适中,相应培育出的烟苗,其茎高、茎直径、根部干重、茎部干重及根冠比最大,因此烟苗的综合素质最好。 相似文献
106.
Summary Deep water rice varieties in general have certain peculiar characters which are associated with floating habit. These characters are (i) early nodal differentiation, (ii) nodal rooting, (iii) spreading habit, (iv) awned grains, (v) brown hull colour, (vi) red pericarp (red rice), and (vii) seed dormancy. Inheritance of these characters and linkage relationship of genes governing these characters were studied in a cross between Pankaj (non floating) and Nageribao (floating) rice varieties. Nageribao, a cultivar from Assam possesses these characters.Early nodal differentiation was observed to be controlled by a single dominant gene, designated as Nd. Nodal rooting was controlled by two dominant complementary genes, designated as Nr
1 and Nr
2. We found an inhibitory factor for spreading habit and one for brown hull colour in Pankaj; the operation of two dominant duplicate genes An
1 and An
2 for controlling awning characters, a single dominant gene Rd for red pericarp colour and a single dominant gene Gd for grain dormancy. Joint segregations between these characters resulted in the assignment of genes in the X linkage group of indica rices with estimated map distances based on the cross-over values. The genes An (awning), Es (spreading habit), Nr (nodal rooting) and Nd (nodal differentiation) were observed to be associated with each other. The gene for red pericarp (Rd) was observed to be linked with the grain dormaney gene Gd. 相似文献
107.
108.
109.
Identification of a diverse mini‐core panel of Indian rice germplasm based on genotyping using microsatellite markers 下载免费PDF全文
Kapil K. Tiwari Anshuman Singh Sasmita Pattnaik Maninder Sandhu Sukhdeep Kaur Sourabh Jain Sushma Tiwari Shweta Mehrotra Mahender Anumalla Rashmita Samal Jyoti Bhardwaj Neha Dubey Vikrant Sahu Gayle A. Kharshing Patu K. Zeliang Kadiri Sreenivasan Pankaj Kumar Swarup K. Parida Sevanthi V. A. Mithra Vandana Rai Wricha Tyagi Pawan K. Agrawal Atmakuri R. Rao Arunava Pattanayak Girish Chandel Ashok K. Singh Ishwari S. Bisht Kangila V. Bhat Gundimeda J. N. Rao Jitendra P. Khurana Nagendra K. Singh Trilochan Mohapatra 《Plant Breeding》2015,134(2):164-171
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining. 相似文献
110.