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81.
The homoeologous groups of chromosomes carrying the genes for some morphological traits in wild wheat Triticum turgidum L. ssp. dicoccoides (T. dicoccoides) were determined, but not the actual chromosomes carrying them. The objectives of this study were to investigate the modes
of inheritance, and determine the chromosomes carrying some morphological traits in wild emmer (2n = 28; AABB), the progenitor of most cultivated wheats. To investigate the inheritance of morphological traits, crosses were
made between T. turgidum L. ssp. durum (T. durum cultivar Chartokhmi (IR10) and T. dicoccoides accessions TA1150 and TA1131. F2 seeds from each cross were grown in the field and six qualitative characters were investigated. Purple coleoptile, purple
auricle, purple culm, hairy auricle, hairy rachilla, and fragility of spike were controlled by single dominant genes. To determine
the chromosomal locations, accession TA1131 was crossed with the complete set of LDN D-genome disomic substitution lines.
Assessments of F2 populations showed that chromosomes 7A, 6A, 7B, 5B, 5A and 3B carried genes for purple coleoptile, purple auricle, purple
culm, hairy auricle, hairy rachilla and brittle rachis, respectively. 相似文献
82.
An original automatic method useful for solving different problems of soil ecology was developed. A special program of image processing was used for assessing the toxicity of objects (infusoria, plant seeds and roots, etc.). 相似文献
83.
Hitherto, an extensive series of analyses is needed to characterize soil samples. According to the data described in the literature, as well as data obtained from our own experiments, the use of maximum hygroscopicity or “Hy” is finally evaluated. By means of statistical analysis, the correlation between pairs of properties was studied for different Ap-horizons from Quaternary deposits at various locations representing the main soil types of Belgium. 相似文献
84.
Hafiz Mohkum Hammad Abdul Khaliq Farhat Abbas Wajid Farhad Shah Fahad Muhammad Aslam 《Communications in Soil Science and Plant Analysis》2020,51(10):1406-1422
ABSTRACT Organic amendments in the soil perform better than synthetic fertilizers in regards to soil fertility and sustainable crop productivity. Experiments were conducted to compare the effects of organic and synthetic fertilizers on soil fertility and wheat (Triticum aestivum L.) productivity. Soil fertility and protein contents of wheat grains (13.2% and 13.3% during 2005–06 and 2006–07, respectively) were improved by organic amendments. However, synthetic fertilizer (at the rate of 150, 100, and 60 kg ha?1 N, P2O5, and K2O, respectively) applications resulted in the maximum grain yield (4.05 and 4.46 t ha?1 during 2005–06 and 2006–07, respectively). The observed and simulated soil organic carbon (SOC) reasonably agreed during RothC model validation (R 2 = 0.99). Economic analysis showed the maximum net profit and relative increase in income ($729 US ha?1 and 309%, respectively) from inorganic treatment. Application of synthetic fertilizers increased grain yield and farm profit while organic manure enhanced grain quality. The RothC model had potential for determining the SOC in organic farming under arid environment. 相似文献
85.
An investigation was conducted near the industrial areas of West Bengal, Indian subtropics to study the effect of emissions through various factories and thermal power plants on the quality of water in lakes, tanks, ponds, even well waters in relation to its use in the welfare of the society (agricultural use, psciculture and other domestic uses). The results showed that intensity of acidity (water pH) as well as concentration of various soluble salts and BOD and COD in the vicinity of an industrial area (i.e. within 100 metres) were very low. A substantially higher acidity and ion concentration were recorded up to 1 km away from industry, where the growth of aquatic plants, organisms and the production of fish (in lakes and tanks) were severely affected. The results further indicated that the acidity of water gradually increases up to pH 5.4 and concentration of sulphates and chlorides (880 and 570 mg 1?1 respectively) between 1–2 km from the industriy, suggesting that aquatic ecosystems and domestic, agricultural and fish production are less affected with increasing distance from industry. 相似文献
86.
氮肥对大白菜硝酸盐累积的影响及合理施用量研究 总被引:18,自引:2,他引:18
对宁夏灌淤旱耕人为土氮(N)肥与大白菜产量及菜体和土体中硝酸盐累积的关系进行了田间试验研究。结果表明,在设计范围内,银川平原复种大白菜的产量及净菜率与施N量成正比;施N肥增加大白菜硝酸盐含量;复种大白菜的最高产量施N量为448.5㎏/hm2,最佳产量施N量为427.5㎏/hm2;大白菜外叶硝酸盐含量高于内叶,内叶硝酸盐含量随施N肥量的增加而增加,外叶硝酸盐含量在高施N时,随生育期延长而增加;施用N肥明显增加土体各土层中的硝态N含量。 相似文献
87.
W.J. Grüneberg P. Freynhagen-Leopold O. Delgado-Váquez 《Genetic Resources and Crop Evolution》2003,50(7):757-766
The yam bean (Pachyrhizus spp.) is a legume tuber / root crop locally grown in Central America, South America and Asia. The tuber is usually consumed raw for its refreshing taste and high moisture content. A recently found P. tuberosus type from a small ecogeographic region in the tropical lowlands of Peru has a high tuber dry matter content and this so-called Chuin-Type is consumed like manioc. This study was conducted to determine the possibility to use the Chuin-Type as a source to incorporate high dry matter into the remaining yam bean gene pool. Three P. tuberosus (Chuin) accessions were crossed with 15 P. ahipa accessions from the Andean highlands resulting in six successful interspecific hybridisations. Successful crosses were confirmed by morphological and agronomical traits as well as multivariate statistics. All hybrid plants were fertile and vigorous. Owing to the fertility and vigour of interspecific hybrids it is assumed that a hybrid between P. tuberosus and P. ahipa might already evolved in the area of origin and that interspecific hybridisation is appropriate to improve the tuber dry matter content in the yam bean which might give the crop new forms of food and processing use. 相似文献
88.
The genetics of the powdery mildew resistance of 15 Hordeum spontaneum-derived winter barley lines were studied in testcrosses with selected cultivars carrying the MIa12 and MIa13 resistance alleles, in order to identify the inheritance of the resistance and to test for linkage with the MIa locus on chromosome 1H (5). A total of 27 genes were identified. Only one of these genes (in line 1–12 x Dura) could eventually be allelic to a gene previously identified in H. spontaneum Koch. A monofactorial dominant inheritance was identified in the majority of the lines. Three of the tested lines possessed recessively inherited genes and in one line a dominant and a recessive gene were identified. In respect to the reaction of the lines against European mildew cultures, lines with a bifactorially inherited resistance had a broader resistance spectrum than those with a monofactorial inheritance, while lines carrying recessive factors showed a moderately expressed resistance. In three cases a linkage with the MIa locus was found, while in two further lines a possible allelism to this locus was indicated by the absence of recombinant progeny plants. By using more than two isolates for linkage analysis, it was possible to identify additional genes for mildew resistance, reaching a maximum number of four genes in the same line. In some cases, a different inheritance was observed for the resistance of the same line against different isolates. It was assumed that different genes exist, each being effective against a different isolate. 相似文献
89.
《Geoderma》2005,124(1-2):193-202
In semiarid climate soils, the establishment of a plant cover is fundamental to avoid degradation and desertification processes. A better understanding of the ability of plants to promote soil microbial processes in these conditions is necessary for successful soil reclamation. Six different plant species were planted in a semiarid soil, in order to know which species are the most effective for the reclamation of semiarid areas. Six years after planting, the rhizosphere soils were studied by measuring chemical (pH, electrical conductivity, total organic carbon and other carbon fractions), physical (% of saggregates), microbiological (microbial biomass carbon and soil respiration), and biochemical (dehydrogenase, phosphatase, β-glucosidase and urease activities) parameters. In general, in all the soil–plant systems plant nutrients, organic matter and microbial activity increased compared to the control soil. For some species, such as Rhamnus lycioides, the increase in the total organic carbon content (TOC) in the rhizosphere zone was almost 200%. A positive correlation was found between TOC and water-soluble carbon (p<0.001); both parameters were negatively correlated with electrical conductivity. Microbial biomass carbon and soil respiration were highest in the rhizosphere of Stipa tenacissima (98% and 60%, respectively, of increase on soil control values) and Rosmarinus officinalis (94% and 51%, respectively, of increase on soil control values). These microbiological parameters were correlated with the percentage of stable aggregates (p<0.01). Enzyme activities were affected by the rhizosphere, their values depending on the shrub species. 相似文献
90.
F.P. Vaccari S. Baronti E. Lugato L. Genesio S. Castaldi F. Fornasier F. Miglietta 《European Journal of Agronomy》2011,34(4):231-238
Carbon sequestration in agricultural soils is a climate change mitigation option since most of cultivated soils are depleted of soil organic carbon and far from saturation. The management practices, most frequently suggested to increase soil organic carbon content have variable effects depending on pedo-climatic conditions and have to be applied for a long time periods to maintain their sink capacity. Biochar (BC), a carbon rich product obtained through carbonization of biomass, can be used for carbon sequestration by applying large amounts of carbon very resistant to decomposition. The BC remains into soil for a long time and there is evidence that the BC stores atmospheric carbon from centennial, to millennial timescales. However most of the agronomic studies on BC application have been made in tropical and sub-tropical climates, while there is a substantial lack of studies at mid-latitudes and in temperate climates. This paper presents the results on an investigation of large volume application of BC (30 and 60 t ha?1) on durum wheat in the Mediterranean climate condition, showing the viability of BC application for carbon sequestration on this crop. BC application also has positive effects up to 30% on biomass production and yield, with no differences in grain nitrogen content. Moreover no significant differences between the two BC treatments were detected, suggesting that even very high BC application rates promote plant growth and are, certainly, not detrimental. The effect of the biochar on durum wheat was sustained for two consecutive seasons when BC application was not repeated in the second year. 相似文献