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21.
22.
S.?Vijayalakshmi Kusum?Yadav Chanda?Kushwaha S.?B.?Sarode C.?P.?Srivastava Ramesh?Chand B.?D.?SinghEmail author 《Euphytica》2005,144(3):265-274
Summary Two RAPD markers linked to gene for resistance (assayed as pustule number cm−2 leaf area) to rust [Uromyces fabae (Pers.) de Bary] in pea (Pisum sativum L.) were identified using a mapping population of 31 BC1F1 [HUVP 1 (HUVP 1 × FC 1] plants, FC 1 being the resistant parent. The analysis of genetics of rust resistance was based on
the parents, F1, F2, BC1F1 and BC1F2 generations. Rust resistance in pea is of non-hypersensitive type; it appeared to be governed by a single partially dominant
gene for which symbol Ruf is proposed. Further, this trait seems to be affected by some polygenes in addition to the proposed oligogene Ruf. A total of 614 decamer primers were used to survey the parental polymorphism with regard to DNA amplification by polymerase
chain reaction. The primers that amplified polymorphic bands present in the resistant parent (FC 1) were used for bulked segregant
analysis. Those markers that amplified consistently and differentially in the resistant and susceptible bulks were separately
tested with the 31 BC1F1 individuals. Two RAPD makers, viz., SC10-82360 (primer, GCCGTGAAGT), and SCRI-711000 (primer, GTGGCGTAGT), flanking the rust resistance gene (Ruf) with a distance of 10.8 cM (0.097 rF and LOD of 5.05) and 24.5 cM (0.194 rF and a LOD of 2.72), respectively, were identified.
These RAPD markers were not close enough to Ruf to allow a dependable maker-assisted selection for rust resistance. However, if the two makers flanking Ruf were used together, the effectiveness of MAS would be improved considerably. 相似文献
23.
Four seed-set groups of plants, viz. unselected ‘general’ and selected ‘high’, ‘medium’ and ‘low’ were constituted in C1 generation from randomly selected autotetraploids of two pea cultivars, T 163 and 5064-S. In C2 generation, ten plants were selected at random in each of the four groups. Two seeds each from selected autotetraploids were drawn and bulked to make 20 seeds in each of the four groups to raise C3 generation. Selection resulted in a gradual shift in seed-set, though the magnitude and nature varied with the group and generation. Improvement in the seed-set from C1 to C3 generation was associated with the increase in bivalents per cell, disjunction index and total chiasmata. Increase in total chiasmata was mostly due to an increase in proximal ones. Increase in seed-set was reflected in improvement of grain yield per plant. 相似文献
24.
Summary The polypeptide composition of Fraction-1-Protein (F1P) from rice × sorghum, rice × wheat hybrids and their respective parents have been analyzed by a microelectrofocusing method. The large sub-unit (LSU) is composed of three polypeptides and the small sub-unit (SSU) of two polypeptides in rice and sorghum parents and rice × sorghum hybrids. Similarly, LSU is composed of three polypeptides in the rice and wheat parents and rice × wheat hybrids. Two polypeptides occur in the SSU of rice parent and rice × wheat hybrids where as only one polypeptide in the wheat parent. These polypeptides also differ in their isoelectric points. Based on the previous reports of F1P inheritance in hybrids in other crops, F1P analysis of rice × sorghum and rice × wheat hybrids does not seem to be an important marker to identify such intergeneric hybrids. Since this is first such report of F1P inheritance in hybrids between distantly related plants, its implication in different modes of inheritance are discussed.Abbreviations F1P
Fraction-1-Protein
- IEF
Isoelectric focusing
- pI
Isoelectric points
- LSU
Large sub-unit
- RuBPCase
Ribulose 1,5-Bisphosphate Carboxylase-oxygenase
- SSU
Small sub-unit 相似文献
25.
Summary Twenty nine strains of vegetable amaranth (Amaranthus tricolor were grown for two successive seasons to study different selection parameters for foliage yield and its nine contributing morphological and quality traits. The strains AV-38 (5.06 kg/plot) and AV-31 (5.04 kg/plot) recorded highest foliage yield, followed by AV-30 (4.78 kg/plot) and AV-23 (4.70 kg/plot). The protein and carotenoid content averaged 1.24 ± 0.03 mg/100 mg and 0.83 ± 0.02 mg/g respectively. The leaves of A. tricolor also have considerable quantities of ascorbic acid (112.33 ± 5.00 mg/100 g) and fibre (8.39 ± 0.10%). The mean of individual cuttings for plant height, leaf size, stem diameter, foliage yield, protein, ascorbic acid and fibre content increased with successive cuttings till third cutting and thereafter showed a decline. Genotypic coefficient of variation (GCV) values ranged from 6.80 to 28.25%. However, the fibre content, branches/plant, leaves/plant, plant height and stem diameter showed lowest values of GCV. The values of heritability estimates were high for all the traits in all the cuttings as well as on pooled basis and ranged from 0.89 for branches/plant to 0.98 for foliage yield. Highest expected genetic advance was noticed for ascorbic acid (57.48%), followed by foliage yield (48.30%) and leaf size (29.51%). 相似文献
26.
Summary A 6×6 diallel was prepared to study the inheritance of leaf angle in T. aestivum L. Genetic analysis in terms of diallel cross parameters and graphic analysis indicated the control of additive gene effects in the expression of this character. The results of F1 analysis were supported by the analysis of F2 data. 相似文献
27.
28.
Shaili Srivastava 《Soil biology & biochemistry》2006,38(7):1904-1911
Aspergillus niger isolated from soil of leather tanning effluent had higher activity to remove chromium then the other fungal isolates. The potency of A. niger was evaluated in shake flask culture by absorption of chromium at pH 6, temperature 30 °C. The toxicity of chromium evaluated in petriplates and soil microcosm seed bioassay test had indicated increase in toxicity with the higher concentration of chromate. A. niger introduced in soil microcosm (40% moisture content) with different concentration of chromate (250, 500, 1000, 1500 and 2000 ppm) removed more than 70% chromium in soil contaminated by 250 and 500 ppm of chromate. However, chromium-contaminated soil (2000 ppm of potassium chromate) mixed with compost (5% and 10%) significantly removed chromium in presence of fungus, A. niger. The results of chromate toxicity in the wheat plants revealed that the peroxidases was induced due to increase of metal stress which was reversed in soil microcosm amended with compost. 相似文献
29.
Supply of 0.01 to 1.0 mM Cd acetates either to the intact seedlings or to the excised leaves of 15 dPisum sativum L. Cv. Bonvilla seedlings inhibitedin vivo nitrate reductase activity (NRA), total soluble protein, chlorophyll, and carotenoids. The inhibition was independent of metal concentrations. In excised leaf tissues, higher concentrations (0.5 to 1.0 mM) of Cd had no conspicuous effect on nitrate assimilation. When NRA was assayed byin vitro method, an increase of 12 to 45% was obtained with Cd in intact and excised leaves. It appears that NRA is more sensitive to Cd concentration than any other parameter examined. 相似文献
30.
The Influence of Glutathione on Physiological Effects of Lead and its Accumulation in Moss Sphagnum Squarrosum 总被引:1,自引:0,他引:1
An attempt has been made to study the physiological andbiochemical responses and to evaluate the bioaccumulationpotential of moss Sphagnum to environmental lead. Supply of0.1 to 100 mM lead acetate caused a loss in chlorophyll andnitrogen content of moss and in nitrate reductase activity in themoss, although the peroxidase activity was increased. Partialrecovery in the above parameters was recorded upon simultaneoustreatment with glutathione. Results also indicate that treatmentwith glutathione increased the bioaccumulation potential bylowering the lead toxicity, which could be the result of inductionof metal binding capabilities of cells as the heavy metal alsoinduced the synthesis of phytochelatins. The moss accumulated asignificant amounts of Pb under both experimental and fieldconditions. The heavy metal accumulated by moss was positivelycorrelated to the soil metal content. The experiments demonstratethat Sphagnum is able to accumulate and tolerate higheramounts of Pb and therefore, it can be used as a bioindicator andphytoremediator of lead contaminated environment. 相似文献