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991.
农业科技示范园作为农业产业调整中重要的组成部分,在产业调整中发挥着越来越重要的作用,以山东泰山苗木花卉科技示范园为例,通过在示范园区的规划设计中多学科的交叉与融合,从多个角度分析、研究现代农业科技示范园区规划设计的理论与方法,与传统农业示范园规划设计相比较,使现代农业科技示范园的内涵更能适应现代化农业发展的需要,使其自身功能结构和空间布局更加完善,产生更大经济、生态、社会效益,最终实现园区的自我维持和可持续发展。 相似文献
992.
基因组原位杂交技术在植物研究中的应用 总被引:2,自引:0,他引:2
基因组原位杂交是以亲本之一的总基因组DNA做探针,另一亲本的基因组DNA做封阻,在荧光原位杂交技术的基础上发展起来的一种染色体/染色质检测技术。在其发展的十几年里,已在植物的基因组研究中发挥了重要的作用。应用这一技术可对多倍体中基因组之间的亲缘关系、基因组组成及起源进行研究;对杂交种中染色体组的组成进行分析;对代换系、附加系和易位系进行有效的鉴定,并对其中的外源染色体或染色体片段的来源、大小、数目及发生位点进行检测和定位。此外,利用基因组原位杂交技术还有助于确定物种间的同源性;研究杂交种中来源不同的染色质在核中的分布;探索B染色体的起源、染色体间的配对、重组、交换等现象。随着基因组荧光原位杂交技术体系的不断发展、完善和改进,其应用范围不断拓展,在植物基因组研究领域中发挥了越来越重要的作用。 相似文献
993.
994.
葡萄试管苗土支撑培养带坨移栽研究 总被引:10,自引:0,他引:10
以土作为培养基支撑物,离体培养葡萄试管苗双节茎段,40天后即达到适于炼苗标准,成苗率95.8%。带坨移入营养钵,在不喷雾,不覆膜,空气湿度低至45%条件下,成活率达96.7%。成活的试管苗炼苗54天后移入大田,移栽成活率为100%,其中特级苗占87.5%,一级苗占12.5%。试验证明,土支撑培养带坨移栽技术是简化试管苗移栽程序,降低成本的有效措施。 相似文献
995.
Summary Callus was obtained from immature excised embryos of triticale using MS medium supplemented with 3 mg/l 2,4-D and 1 mg/l kinetin. The presence of 2,4-D was essential for continued callus proliferation. Plantlets were induced from the calli by sub-culturing on medium either devoid of auxin or containing 0.1 mg/l 2,4-D. The capacity to produce callus and to form organs and plantlets differed markedly among the genotypes used. Lines also had distinct response to presence and absence of 2,4-D in the regeneration media. The callus of most triticale lines used differentiated into organs more readily on MS medium supplemented with 0.1 mg/l 2,4-D than on medium without growth regulators. Very high frequencies (up to 75%) of plantlet regeneration were observed in several of the triticale lines studied. 相似文献
996.
Continuous Plant Regeneration from Established Embryogenic Cell Suspension Cultures of Italian Ryegrass and Tall Fescue 总被引:8,自引:0,他引:8
The suitability of different protocols was compared for entire plant regeneration by somatic embryogenesis, of the forage plants Lolium multiflorum Lam. (Italian ryegrass) and Festuca arundinacea Schreb. (tall fescue). In the first protocol, miniature embryos were used as starting material, while mature seeds were retained in the other two. Whichever the considered protocol, undifferentiated calli were produced on Murashige and Skoog MS medium supplemented with 2,4-D. The calli were subcultured in the dark on solid MS agar medium, containing 5 mg/1 2,4-D (protocol 2) or on solid MS medium followed by transfer to a rotated liquid MS medium with 2 mg/1 2,4-D (protocol 1). In these conditions, induction of somatic embryogenesis occurred, and whole plants were regenerated during a limited lapse of time, upon transfer in the light, to MS medium supplemented with BAP but devoid of 2,4-D. The simultaneous elimination of 2,4-D and transfer to light appeared essential for full regeneration of the plants. Using this characteristic, an additional step was added to a new protocol (protocol 3) in which microcalli, cultured on liquid MS medium containing 5 mg/1 2,4-D, were transferred to the same medium with 2 mg/1 2,4-D, in the dark. In these conditions, the suspensions kept their embryogenic potential for months. In all cases, plantlets were successfully transferred into the soil. An evaluation of the somaclonal variation potential of the plants issued from each protocol is now underway. 相似文献
997.
‘BJ 104’ was the most widely grown pearl millet hybrid in India until it became susceptible to downy mildew (DM) in 1984—85. Residual variability for resistance was found in both parental lines, 5141 B (maintainer of 5141 A) and J 104, and through four generations of pedigree selection under intense disease pressure in the DM nursery, two lines, IC-MA841 (from 5141 B) and ICMP 84814 (from J 104), were selected resulting in a reconstituted DM resistant hybrid (‘ICMH 84814’) which was equal in yield to the original ‘BJ 104’. The reconstituted hybrid, though phenotypically similar, can be distinguished from “BJ 104” being slightly taller, flowers later, has heavier heads, and 1000-seed weight, but tillers less. A similar exercise was attempted on Tifton 23 B, the female parent of the first widely grown hybrid (‘HB 3’— the male parent was also J 104), but no variability for resistance to DM was found. 相似文献
998.
The prediction of grain and stover quality parameters in maize {Zea mays L.) by near infra-red reflectance spectroscopy (NIRS) was studied. A total of 110 grain and 135 stover samples originating from different genotypes and environments were assayed. Calibration equations for content of crude protein (CP), crude fat (CF), starch (ST), and water soluble carbohydrates (WSC) in grain were obtained by multiple linear regression of known manual values on NIRS data from the odd numbered samples. Calibrations for CP, acid detergent fibre (ADF), in vitro digestible organic matter according to the Tilley & Terry (IVDOM-T & T) and the gas production (IVDOM-Gp) method, respectively, and metabolizable energy (ME) in stover were developed analogously. Equations were validated with the evennumbered .samples and for ME additionally with the 1584 stover samples from an experiment with 66 F1 hybrids tested in six environments. The coefficients of multiple determination (R2) of the prediction equations ranged from 0.80 for IVDOM-Gp and ME in stover to 0.94 for CP in grain. Standard errors of calibration (SEC) and prediction (SEP) were in most cases not higher than commonly reported for conventional manual assays. With regard to the correct ranking of hybrids, prediction equations for ME applied well to stover samples from other environments with one exception. We concluded that NIRS can evaluate the quality traits investigated to a similar degree to that of conventional methods of analysis. Since NIRS is simple and safe to operate and allows rapid screening of several quality traits simultaneously, it should be particularly attractive for breeding purposes. 相似文献
999.
Summary In vitro pollen germination at 10°C, 14°C and 22°C of four groups of two pure line tomato varieties was compared with their plant growth at 19°C D/10°C N under controlled environmental conditions. Generally, pollen germination was slow at 10°C but after 6 h the percentage of germination was similar to that at 22°C. Maximum germination was obtained at 14°C already after 4 h. The longest pollen tubes occurred at 22°C. The two varieties within each group differed significantly from each other for percentage of pollen germination. For one group, this difference was greater at 10°C than at 22°C. The varieties in two groups also differed significantly for pollen tube growth. These differences in pollen tube growth rate were greater at 22°C than at 10°C. There was no clear relationship between pollen germination, pollen tube growth and plant growth in any of the four pairs of varieties. The results are discussed with regard to the possibility of pollen selection at low temperature in order to improve the efficiency of breeding for growth at low temperature. 相似文献
1000.
Eviatar Nevo Avigdor Beiles Yitzchak Gutterman Nurith Storch Diane Kaplan 《Euphytica》1984,33(3):717-735
Summary Populations of wild emmer wheat, Triticum dicoccoides, in Israel, originating from diverse habitats, and tested earlier for allozyme (Nevo et al., 1982) and disease resistance polymorphisms (Moseman et al., 1983a, 1983b; Nevo et al., 1984a, 1984b), were compared and contrasted for performance in agronomically important phenotypic traits. The traits compared involved 10 variables comparing germination, earliness, biomass and yield variables. The field experiments were conducted in 1980, 1981 and 1982 in two relatively standardized and contrasting environments: mesic (Mount Carmel, Haifa) and xeric (Acedat Farm, and Sede Boqer, in the northern Negev desert). The experimental design involved 12 population quadrangles at Avedat Farm in 1980, and rows of randomized genotypes of five populations in both Haifa and Sede Boqer in 1981 and 1982.The results indicate that the characters studied are partly genetically determined. Striking genetic variation was found between and, at least in some characters, also within populations in each site, whereas remarkable environmental variation including genetic-environmental interaction was found between the mesic and the xeric sites. We conclude that natural populations of wild emmer wheat in Israel vary not only in genetic polymorphisms of allozymes and disease resistance, but also in quantitative traits of agronomic importance. These traits are economically significant and should be conserved and utilized in wheat crop improvement. 相似文献