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81.
82.
生物有机液体混合肥对甜高粱根系形态特征的影响 总被引:1,自引:1,他引:0
为揭示生物液体有机混合肥对陕北农牧交错区青贮饲草作物根系形态特征的影响,通过盆栽控制试验,以甜高粱(Sorghum bicolor L.)为材料,设置不同浓度的生物活性水(BMW)(B1、B2、B3和B4)和Aidoora溶液(A1、A2和A3)处理,并测定甜高粱幼苗期的根系形态特征。结果表明:在大多数单一液体肥和混合液体肥下,甜高粱的根系生物量(RB)、根冠比(RSR)、根系体积(RV)、总根长(TRL)、根系表面积(RSA)、平均根直径(RAD)、比根长(SRL)和比根面积(SRA)均显著高于CK,表明BMW和Aidoora溶液有利于促进甜高粱苗期根系生物量积累和根系吸收能力;甜高粱的RB、TRL和RSA两两间均呈明显的正相关关系,表明根系表面积和总根长均随着根系生物量的升高而增加。综上分析表明,B3A2和B3A3相对于其他BMW和Aidoora混合液体肥,有利于促进甜高粱幼苗根系生物量积累和根系形态建成。 相似文献
83.
Investigation into the paternity of four abaca (Musa textilis L, Nee) hybrids was done to ascertain the mode of transmission of selected morpho-agronomic traits and to detect possible heterosis. In situ morphological characterization was undertaken using twenty five qualitative and six quantitative characters. Results revealed that a great majority of the qualitative traits were shared by both parents and their hybrids. For the rest, the qualitative traits were inherited from one or the other parent though some variant phenotypes (i.e. chimerism) were also noted in the hybrids. Cases ofheterosis were also observed and this could be exploited to increase fiber yield in the hybrids. Though inconclusive due to factors such as the heterogenous nature of abaca plants in the field and the susceptibility of morphological traits to environmental fluctuations, this study has provided baseline information on abaca hybridity that can be verified using more robust technologies as molecular markers. 相似文献
84.
英国爱丁堡皇家植物园的地被植物 总被引:2,自引:0,他引:2
介绍了主要生长于英国受丁堡皇家植物园内分属于Xun子属Cotoneaster、萎陵菜属Potentilla、悬钩子属Rubus、野珠兰属Stephanandra、虎儿草属Saxifraga、刺柏属Juniperus、廖属Polygonum、Microbiota、水杨梅属Geum、富贵草属Pachysandra、玉簪属Hosta等11个属中的30种地被植物。除较详细地描述了30种地被植物的形态特征外,还介绍了各属植物的生长习性和每种植物的耐低温能力。 相似文献
85.
This study was aimed at the induction of morphological mutations for increasing genetic variability and making available additional genetic markers for linkage studies in chickpea (Cicer arietinum L.). A wilt‐resistant, well‐adapted chickpea cultivar of central India,‘JG 315’(Jawahar gram 315), was used for the induction of mutations. Seeds presoaked in distilled water for 2 h were treated with ethyl methane sulphonate (EMS) using six different concentrations (0.1, 0.2, 0.3, 0.4, 0.5 and 0.6%) and two different durations (6 and 8 h). Several morphological mutants were identified in M2. One of the mutants, isolated from a treatment of 0.3% EMS for 8 h, had five to nine large leaflets per leaf in comparison with 11‐17 normal‐sized leaflets per leaf observed in the parental cultivar ‘JG 315′. The mutant was designated broad‐few‐leaflets. Many leaves of this mutant showed a cluster of three to five overlapping leaflets at the terminal end. The other mutant, designated outwardly curved wings, was isolated from the 0.5% EMS treatment for 6 h. In this mutant, the wings were curved outwards, exposing the keel petal, while the wings in typical chickpea flowers are incurved and enclose the keel. The lines developed from the broad‐few‐leaflets and outwardly curved wings mutants were named JGM 4 (Jawahar gram mutant 4) and JGM 5, respectively. Inheritance studies indicated that each of these mutant traits is governed by a single recessive gene. The gene for broad‐few‐leaflets was designated bfl and the gene for outwardly curved wings was designated ocw. The locus bfl was found to be linked with the locus lg (light green foliage) with a map distance of 18.7 ± 6.3 cM. 相似文献
86.
Breeding of Raphanus sativus‐Brassica rapa monosomic chromosome addition lines (MALs, 2n = 19) was carried out by backcrossing the synthesized amphidiploid line, Raphanobrassica (R. sativus×B. rapa, 2n = 38, RRAA, line RA89) with R. sativus cv. ‘Shogoin’ (2n = 18, RR). In the first cross of Raphanobrassica× radish, four sesquidiploidal BC1 plants (2n = 28, RRA, RA89‐36‐1, RA89‐31‐1, RA89‐31‐2, RA89‐31‐3) were successfully developed. In these plants, the chromosome configurations of 9II + 10I and 10II + 8I were observed frequently at first metaphase (MI) of meiosis in pollen mother cells (PMCs). The RA 89‐36‐1 plant produced many seeds in the reciprocal backcrosses with radish. About 50% of the BC2 plants obtained from the cross of RA89‐36‐1 plant × radish were 2n = 19 plants, followed by 2n = 18 plants (24%) and 2n = 20 plants (19%). In the reciprocal cross, 2n = 19 plants were also developed at the rate of 40%. From analysis of specific morphological traits, 2n = 19 plants were classified into eight types (a‐h). When 25 selected primers were used in polyacrylamide gel electrophoresis, random amplified polymorphic DNA (RAPD) markers derived from B. rapa for each type of MAL were detected in numbers between three for e‐type and 16 for b‐type. RAPD markers specific for each type alone were from one (OPE 05‐344) for h‐type to nine for b‐type. In the g‐type, no marker specific to this type alone was observed. However, 19 bands were common between at least two types. These MAL plants exhibited predominantly the chromosome configuration of 9II + 1I at MI of PMCs, pollen and seed fertility being the same level as the radish cv. ‘Shogoin’. From the morphological traits and DNA markers, eight different MAL types among 10 expected were identified. 相似文献
87.
Summary Cultivated almonds (Prunus dulcis (Miller) D.A. Webb) in Morocco are still propagated from seeds by farmers to overcome transplant failure of grafted trees. Almond collections in southern Morocco conducted since 1975 have resulted in the selection of clones planted at 3 experimental stations. Principal component analysis (PCA) was used to compare kernel, nut, leaf, and growth habit characteristics among 67 selected Moroccan clones and 14 introduced cultivars. Clustering of clones from similar countries and collection areas would suggest the existence of different almond populations. The Moroccan clones did not cluster separately from the foreign cultivars. Three Moroccan clones had exceptionally large nuts and kernels while 7 selections had high yield potential due to high spur density. Moroccan selections tended to be characterized by small leaves in comparison to foreign cultivars. No evidence was found to suggest the existence of separate populations within the Moroccan almond germplasm. 相似文献
88.
Morphological variation in Astragalus hamosus L. and Coronilla scorpioides L. populations of Tunisia
Morphological variation between Astragalus hamosus and Coronillascorpioides populations was studied using local germoplasm collected in northern and central Tunisia. Twenty-one morphological traits
were recorded and data were analysed using complementary statistical analysis. Considerable variation based on morphological
and agronomical traits was found between populations and for both species. Pod and peduncle lengths as well as flowers number
were the most discriminant variables between populations. Differences were also found for variables like seed number per pod,
seed yield and dry matter production. Significant correlations were found between plant traits and the environmental parameters
of the origin sites. This study revealed enough variation among populations to initiate a selection programme for pasture
improvement in arid and semi-arid areas of Tunisia, where the two species are well adapted.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
Types and components of resistance to Fusarium head blight of wheat 总被引:18,自引:2,他引:18
A. Mesterházy 《Plant Breeding》1995,114(5):377-386
Resistance of wheat to Fusarium head blight caused by Fusarium graminearum and F. culmorum was identified in natural epidemics in 1985 and 1987 as well after artificial inoculations (1983–1988 and 1984–1987). Out of 25 genotypes tested, five were identified with no significant difference in head blight scores, but differing significantly in yield after artificial inoculation, i.e. tolerance differences were detected at different resistance levels. Some genotypes that were similar in yield or head blight scores differed in seed infection severity. Genotypes with awns were more susceptible to head blight when tested under natural epidemic condition in the field; but this trait did not influence head blight severity in artificial inoculations. Dwarf genotypes were more severely infected by head blight than tall genotypes under natural conditions, but genotypes of different plant height classes were similarly susceptible after artificial inoculations. In the early generations of a breeding programme resistance measured by visual evaluation of artificial inoculation is the most important way to screen. If selection of dwarf and awned genotypes cannot be avoided, the higher susceptibility caused by awns and dwarfness under natural epidemic conditions can be decreased by a higher level of physiological resistance, as variability in physiological resistance is available. In later generations, traits like percentage of seed infection or tolerance can be identified by additionally measuring yield reduction. Stability of disease reaction appears to be connected with resistance level, the most resistant genotypes are the most stable, and the most susceptible ones tend to have more unstable reactions in different epidemic conditions. 相似文献
90.
Orientation and integration of the classical and molecular genetic maps of chromosome 11 in rice 总被引:8,自引:0,他引:8
M. L. P. Abenes R. E. Tabien S. R. McCouch R. Ikeda P. Ronald G. S. Khush N. Huang 《Euphytica》1994,76(1-2):81-87
Summary The classical genetic map and molecular map of rice chromosome 11 were oriented to facilitate the use of these maps for genetic studies and rice improvement. Three morphological markers (d-27, z-2, and la) were crossed to a rice breeding line, IRBB21, which has the Xa-21 gene for bacterial blight resistance. Three F2 populations were analyzed with RFLP markers known to be located on chromosome 11. Segregation analysis of molecular markers and morphological markers was used to construct an RFLP map for each population. The recombination frequency between markers varied from population to population although the marker order on the maps was the same for all three populations. Based on a common set of markers mapped in the three populations, an integrated map was generated consisting of both RFLP and morphological markers. The genetic distance between markers on this map was determined by taking a weighted average of the data from the three populations. The oriented map serves as a bridge to understand the relationship between the classical and molecular linkage maps. Based on this information, the location of several genes on the classical map can be approximated with respect to RFLP markers without having to map them directly. 相似文献