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141.
An attempt was made to transfer male-sterility, mslc, from the Cornerstone mutant of tetraploid wheat to diploid wheat. The N-banding technique revealed that chromosome 4 A of tetraploid wheat does not pair with chromosome 4 of diploid wheat in triploid F1 hybrids: consequtntly the transfer of male-sterility gene(s) from tetraploid wheat to diploid was not successful. The culchiane induced ampliploids possessing AAAABB in mslc background were fully fertile indicating the complete compensation of mslc by the newly introduced A genome of T. monocaccum. The fertility compensating gene(S) presumably located on chromosome 4 of diploid wheat may be used to produce hybrid wheat by the XYZ system. 相似文献
142.
The development of genotypes, which can be adapted to a wide range of diversified environment, is the ultimate goal of plant breeders in a crop improvement program. In this study, several stability methods were used to evaluate the genotype by environment interaction (GE) in 11 lentil (Lens culinaris Medik) genotypes. The genotypes were evaluated for grain yield at 4 different locations for 3 years in semi arid areas of Iran. The testing locations have different climatic and edaphic conditions providing the conditions necessary for the assessment of stability. A combined analysis of variance, stability statistics, rank correlations among stability statistics and yield stability statistic were determined. Significant differences were detected between genotypes and their GE interactions. Different univariate stability parameters were used to determine stability of the studied genotypes. The level of association among the parameters was assessed using Spearman's rank correlation. The different stability statistics which measured the different aspects of stability was substantiated by rank correlation coefficient. Rank-correlation coefficients between yield and some stability parameters were highly significant. Genotypes mean yield (Mean) was significantly correlated to the Lin and Binns stability parameter PI (r = 0.93*
*í) and desirability index Di (r = 0.89*
*í). A principal component analysis based on rank correlation matrix was performed for grouping the different stability parameters studied. In conclusion, based on most stability parameters, the genotypes G2, G5 and G9 were found to be the most stable. Results from rank correlation and principal component analysis showed that the stability variance (σi
2) was strongly correlated with Wricke's ecovalance, stability parameters of Plaisted and Peterson, and Plaisted. 相似文献
143.
144.
145.
The morphological and genetic variations in somaclones of chili pepper (Capsicumannuum L.) derived from tissue culture were evaluated. Cotyledonary node explants of cultivars, Shishitou and Takanotsume, were
cultured on Murashige and Skoog (MS) medium supplemented with benzyladenine (BA)5 mg/l for shoots regeneration and regenerated
shoots were rooted on MS medium supplemented with naphthalene acetic acid(NAA) 0.1 mg/l and indol-3-butyric acid(IBA) 0.05
mg/l. The regenerated plants(R0) were selfed to obtain seeds for next generation (R1 lines). Qualitative characters were studied in R0generation and both qualitative and quantitative characters were studied in R1 generation. In R0 generation, variations were noticed in plant growth habit, stem color, flower color and color of unripe fruits, and expression
of anthocyanin in unripe fruits. Comparison among the R1 lines and their parents were made for morphological and agronomic characters. Significant variation among R1 lines and differences between R1 lines and their parents were observed. Genetic variations among three somaclones were revealed by random amplified polymorphic
DNA (RAPD) analysis. Variation, such as early flowering and increase of yield components, is an indication of the response
to selection for any specific character. Occurrence of productive variants among somaclones of established cultivars, like
Shishitou and Takanotsume, indicates the possibility of their improvement through somaclonal variation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
146.
Md Firoz Mortuza Norihiko Tomooka Safiullah Habibi Tetsuya Akatsu Salem Djedidi Ken Naito 《Soil Science and Plant Nutrition》2020,66(2):285-298
ABSTRACT
Vigna riukiuensis plant – a rare type of vigna, found only in Taiwan and the islands of Okinawa prefecture, Japan – possesses intrinsic property of high level of salt and heat tolerance. To understand the diversity and identify suitable rhizobia, multiphase characterization of root nodule bacteria associated with V. riukiuensis grown in Ishigaki and Iriomote Islands of Okinawa prefecture was performed. Multigene phylogenetic analysis of housekeeping genes based on 16S rRNA gene sequences, 16S-23S rRNA gene internal transcribed spacer (ITS) and 23S rRNA gene sequences identified three main groups closely similar to Bradyrhizobium japonicum, B. elkanii and B. jicamae family. However, analysis of symbiotic nifH and nodD1 genes and their phylogenetic trees showed similar topology, having only few discrepancies in comparison to the housekeeping gene phylogeny. Interestingly, for some of the isolates having similarity with B. elkanii, growth was observed at 40°C, which exceed the highest record for B. elkanii to the best of our knowledge. All the isolates were observed to have the capability of forming root nodules and fix nitrogen in their original host plant V. riukiuensis and two other crops: soybean and mungbean. Most of the isolates showed similar or higher nitrogen-fixing capability in comparison with B. diazoefficiens USDA110 in V. riukiuensis and V. radiata (mungbean), and Iri 5/6 in V. riukiuensis, Iri 5/12 in soybean and Ishi 7/2 in mungbean showed highest acetylene reduction assay (in µmol/h/gm nodule dry weight) activity, which was significantly higher than B. diazoefficiens USDA110. In addition, six isolates attained higher soybean biomass production compared with B. diazoefficiens USDA110, suggesting high symbiotic compatibility with soybean. Among them, Iri 5/7 of B. elkanii group contributed 29% higher soybean biomass production than B. diazoefficiens USDA110 and could grow at 40°C, hence it could be a promising soybean inoculant in the tropics. 相似文献
147.
Mahmoud Solhi Hossain Shareatmadari Mohammad A. Hajabbasi 《Water, air, and soil pollution》2005,167(1-4):59-71
Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. The success of a phytoextraction process depends on adequate plant yield (aerial parts) and high metal concentrations in plant shoots. A pot experiment was conducted to investigate the combination effects of plants [sunflower (Helianthus annuus) and canola (Brassica napus)] with soil treatments (manure, sulfuric acid and DTPA). Treatments, including two plants and seven soil treatments, which applied according to completely randomized factorial design with three replications. The largest shoot dry weight biomass production occurred in manure treatments for both plants. The maximum shoot concentrations of Pb and Zn were 234.6 and 1364.4 mg kg?1 respectively in three mmoles DTPA kg?1 treatment of sunflower. Furthermore the results showed that sunflower had a higher extracting potential for removal of Pb and Zn from polluted soil. 相似文献
148.
Md. Motaher Hossain Laboni Yasmin Md. Tanbir Rubayet Hajime Akamatsu Naoki Yamanaka 《Plant pathology》2022,71(6):1355-1368
Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is a major threat to soybean production in Bangladesh. Understanding the yearly changes and the current status of pathogenic structures is essential for developing appropriate breeding strategies for obtaining ASR-resistant soybean lines. Thirty-four P. pachyrhizi samples were collected from ASR hotspot areas (Chandpur, Lakshmipur, Noakhali, Barisal and Bhola districts) of Bangladesh in 2018 and 2019 and evaluated for pathogenicity on 12 soybean differential lines. The tested samples showed similar and dissimilar pathogenicity patterns on the differentials, yielding 21 distinct pathotypes. The cluster analysis, principal coordinate analysis and principal component analysis of the disease phenotypes of 47 samples collected in 2016, 2018 and 2019 indicated a higher pathogenic diversity and virulence variation in the P. pachyrhizi samples of 2018 and 2019 compared to that of 2016. The pathogenicity profiles of the Bangladeshi P. pachyrhizi samples appeared distinct from those of Argentinian and Brazilian samples, but showed slight similarities with Japanese, Mexican and Paraguayan samples. Furthermore, none of the resistance genes for P. pachyrhizi (Rpp genes) was solely effective against all the tested samples from 2018 and 2019, while samples (BdRP-48, BdRP-56 and BdRP-58) virulent to all Rpp1–Rpp6 genes were detected. The Rpp-pyramided line No6–12–1, carrying Rpp2, Rpp4 and Rpp5, was capable of conferring robust resistance to these virulent samples. Altogether, these results indicate an increase in the virulence of the current ASR pathogen in Bangladesh, which can be resolved by pyramiding different resistance genes in soybean cultivars. 相似文献
149.
Golbar HM Izawa T Kuwamura M Okamura K Fujita D Tagami Y Sasai H Yamate J 《Journal of toxicologic pathology》2011,24(4):233-237
A neoplastic nodular lesion consisting of an admixture of granular cell tumor and adenocarcinoma was found in the uterus of a 26-month-old Djungarian hamster. Neoplastic cells of the uterine adenocarcinoma showed an epithelial nature in their growth patterns and by cytokeratin-immunopositive reaction, exhibiting nuclear pleomorphism. The granular cells had an abundant amount of fine granular eosinophilic cytoplasm and eccentric or central nuclei with no nuclear atypia; the granular structures were positive for periodic acid-Schiff with diastase resistance and were confirmed as lysosomes/autophagosomes by electron microscopy; immunohistochemically, the cells reacted to desmin, vimentin and α-smooth muscle actin and negatively for neurogenic, histiocyte/macrophage or epithelial markers, indicating smooth muscle origin. Because these tumors were generated from different cell origins, a diagnosis of collision tumor was made. 相似文献
150.
Nursery practice using microbial inoculants was performed to find out the efficacy of the inoculants on seed germination and
seedling growth of sissoo (Dalbergia sissoo Roxb.). Microbial inoculants or effective microorganisms (EM) are a mixture of many different beneficial microorganisms in
a solution. The seedlings were grown in a mixture of sandy soil and cowdung (3:1) kept in polybags with pouring EM solution
at different concentrations (0.1%, 0.5%, 1%, 2%, 5% and 10%) before and after a week of sowing the seeds. Seed germination
rate and growth parameters of seedlings were measured, such as, shoot and root length, vigor index, fresh and dry weight of
shoot and root and total biomass increment. The nodulation status influenced by EM was also observed along with the measurement
of pigment contents in leaves. The highest germination rate (69%) was observed in 2% EM treatment, followed by 67% and 65%
in 1% and 5% EM. The highest shoot length (33.2 cm) was in 2% EM, whereas highest root length (26.3 cm) was in 1% EM. Both
fresh and dry weights from shoot and root, were maximum (4.16 g and 1.57 g; 2.12 g and 0.83 g respectively) in 2% EM and were
significantly (p ≤ 0.05) different from control. Vigor index was highest (4071) in 2% EM, which was significantly (p ≤ 0.05) different from control. Total dry weight increment was highest in 2% EM treatment, followed by 1% and 5% concentrations
of EM. Nodulation number was higher at very low (0.1%) concentration of EM solution but it normally decreased with the increase
of EM concentrations. The contents of chlorophyll a, chlorophyll b and carotenoid were highest (60.11, 17.05 and 42.48 mg·L−1 respectively) in 2% EM treatment and lowest (39.35, 13.55 and 27.29 mg·L−1 respectively) in control treatment. Therefore, low concentration of EM (up to 2%) can be used for getting maximum seed germination
rate and seedling development of Dalbergia sissoo Roxb. 相似文献