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181.
182.
Mark J. Bassett 《Euphytica》2005,141(1-2):139-145
The inheritance of the virgata pattern of partly colored seed coats found in common bean (Phaseolus vulgaris L.) Early Giant (EG) was studied by a series of test crosses with line 5-593 and genetic stocks developed by backcrossing selected genes into the recurrent parent 5-593, a Florida dry bean breeding line with a self-colored, black seed coat with genotype T Z Bip P [C r] J G B V Rk. Analysis of the F2 from the cross EG × 5-593 led to the hypothesis that the virgata pattern of EG has genotype t z bipvgt, where vgt stands for virgata. The test cross EG × t z virgarcus BC3 5-593 confirmed the hypothesis that EG carries t z from data recorded in F1, F2, and 27 F3 progenies from randomly selected F2 plants. The F3 segregation was also consistent with the hypothesis that a single recessive gene converts virgarcus into virgata. The test cross EG × t z bip bipunctata BC3 5-593 failed to show genetic complementation in F1 progeny, and the F2 segregated 3:1 for the parental phenotypes virgata and bipunctata, respectively. Including previously published data, all possible crosses were made among bipunctata, virgata, and virgarcus parents, supporting a multiple allelic series at Bip. We propose the gene symbol bipvgt for the new allele at Bip, where the allelic series has the order of gene dominance Bip > bipvgt > bip. Based on test crosses, the complete seed-coat color and pattern genotype of EG is tz bipvgt P [C r] J G B vlae rkd.  相似文献   
183.
Inter-provenance hybrids of Pinuscaribaea var. hondurensis wereprogeny tested in Queensland, Australia inorder to assess the feasibility ofincorporating some desirable traits intothe local breeding population, consistinglargely of a single upland provenanceMountain Pine Ridge (MPR). Data onphenotypic traits up to seven years fromplanting revealed that an inter-provenancehybrid, MPR × coastal had greater diameter,straightness and wind-firmness, and fewerramicorns than the MPR control provenance.The data were mostly consistent for twowidely separated sites, and also whenpooled across those sites (p <0.05). In addition, hybrid vigor for treevolume was apparent (p < 0.05).Trees of coastal × Guanaja Island, and purecoastal provenances were as large as thoseof the MPR provenance but had fewerramicorns. Even though the coastal ×Guanaja provenance seemed to produce treesthat were more crooked than the MPRprovenance, there was evidence at leastwithin one site to suggest that the hybridtrees were superior in terms ofwind-firmness (p < 0.01). Breedingfor hybrid vigor and pedigree selection ofthe priority hybrid, MPR × coastal aresuggested as future measures. Pureprovenance populations of coastal andGuanaja island are to be bred as sublinesto the MPR breeding population for futureuse in inter-provenance hybridization andfor gene conservation.  相似文献   
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Genetic evaluation aims to identify genotypes with high empirical breeding values (EBVs) for selection as parents. In this study, 2157 potato genotypes were evaluated for tuber yield using 8 years of early‐stage trial data collected from a potato breeding programme. Using linear mixed models, spatial parameters to target greater control of localised spatial heterogeneity within trials were estimated and variance models to account for across‐trial genetic heterogeneity were tested. When spatial components improved model fit, correlations of errors were mostly small and negative for marketable tuber yield (MTY) and total tuber yield (TTY), suggesting the presence of interplot competition in some years. For the analysis of multi‐environment trials, a variance model with a simple correlation structure (with heterogeneous variances) was the most favourable variance structure fitted for TTY and PTY (per cent marketable yield). There was very little difference in model fit when comparing a factor analytic structure of order 2 (FA2) with either FA1 or simple correlation structures for MTY, indicating that simple variance models may be preferable for early‐stage genetic evaluation of potato yield.  相似文献   
186.
M. Ahmad  Mark E. Sorrells 《Euphytica》2002,123(2):235-240
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   
187.
Reduction of ferric myoglobin (metmyoglobin, MetMb) to its ferrous form is important for maintaining fresh meat color because only reduced myoglobin can bind oxygen to form the consumer-preferred cherry red color in fresh meat. The objective of this study was to characterize an apparent mitochondria electron transport chain (ETC)-linked pathway for MetMb reduction in vitro. MetMb was reduced in the presence of mitochondria and succinate (p < 0.05); mitochondria or succinate alone did not facilitate MetMb reduction relative to controls (p > 0.05). Flushing samples with oxygen greatly decreased MetMb reduction, while flushing with argon increased MetMb reduction when compared with controls (p < 0.05). ETC inhibitors were used to localize the site where electrons became available for MetMb reduction. MetMb reduction was increased by rotenone addition and decreased by malonic acid (p < 0.05); the reduction was completely abolished by additions of antimycin A or myxothiazol when compared with controls (p < 0.05). These results suggest that electrons become available for MetMb reduction at a site(s) between complex III and IV. Mitochondrial ETC-linked MetMb reduction increased with increased mitochondrial density and succinate concentration (p < 0.05); the greatest MetMb reduction was observed at pH 7.2 and 37 degrees C, and ETC-linked MetMb reducing activity decreased with time postmortem (p < 0.05). These results indicate that ETC-linked MetMb reduction exists but would be minimally active in postmortem muscles.  相似文献   
188.
Biphenyl and several plant secondary metabolites (PSM) (carvone, isoprene, limonene, naringin, and coumarin) and surfactant (hydroxypropyl-β-cyclodextrin, (HP-β-CD)) have been shown to improve aerobic polychlorinated biphenyl (PCB) removal by several bacterial species. The objective of this study was to determine whether these treatments also affect PCB removal and microbial community structure in a high organic matter soil (Pahokee soil series with 67% organic matter) and low organic matter soil (Woolper soil series with 6% organic matter), as determined by monitoring changes in PCB levels and phospholipid fatty acids (PLFA) profiles in laboratory microcosms amended with these compounds. Biphenyl enhanced di-chlorinated and tri-chlorinated biphenyl removal in both soils, but PSM did not improve removal of these congeners. On the contrary, HP-β-CD decreased PCB removal when used in combination with biphenyl. Two-way analysis of variance indicated that HP-β-CD significantly increased tetra- and penta-chlorinated biphenyl removal from the high organic matter soil, but not from the low organic matter soil. Principal components analysis of PLFA data indicated that HP-β-CD increased proportions of 18:1ω7c associated with Gram-negative bacteria, but decreased 10me16 and 10me17 lipid associated with Gram-positive bacteria, while biphenyl and PSMs had no detectable effects on soil microbial communities. PCB removal was not correlated to any PLFA. In conclusion, PSM previously shown to enhance PCB removal in soil-free systems were not effective in two divergent soils evaluated in this study, and HP-β-CB had increase, decrease, or no effect on PCB removal depending on types of PCB congeners, soils, and co-amendments.  相似文献   
189.
190.
The effect of Pseudomonas putida (isolate M17) on Rhizobium phaseoli nodulation of the common bean, Phaseolus vulgaris, was investigated under field and greenhouse conditions. The results indicated that P. putida markedly increased nodulation compared to R. phaseoli controls. Furthermore, 2-ketogluconic acid, a phosphate-solubiliring compound, was detected in P. putida M17. This could imply an increased P supply to roots of P. vutgaris, which may function to increase nodules. Bean yields and shoot fresh weight were not significantly altered by the addition of P. putida M17.  相似文献   
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