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41.
试验通过比较17个不同荔枝品种接穗高接在双肩玉荷包树体后,嫁接口的愈合状况,愈伤、表皮生长情况,嫁接成活率,叶片矿质元素含量、枝梢生长量以及各品种高接后果实产量与品质的差异,综合分析各品种与双肩玉荷包之间亲和性与高接后产量与品质指标,以期筛选优良的砧穗组合。结果表明:双肩玉荷包高接妃子笑、蜜荔、马贵荔的嫁接口完整愈合、愈伤和表皮生长状况良好、叶片矿质营养元素水平较高,亲和性较好;高接马贵荔、蜜荔的产量较高,高接无核荔、妃子笑、鸡嘴荔、岭丰糯的品质较好。综合考虑各高接组合亲和性与品质、产量表现,初步认为妃子笑、蜜荔、马贵荔适合双肩玉荷包高接换种,鸡嘴荔、庙种糯、井岗红糯、无核荔、灵山香荔、英山红、桂糯、大丁香还需要进一步观察研究。  相似文献   
42.
基于大兴安岭北部林区19块样地内104株天然兴安落叶松实测生物量数据,建立兴安落叶松天然林地上总量和分量相容性生物量模型,分别采用权函数和联立线性方程组消除方程的异方差和度量误差。结果表明:1)含度量误差的单木生物量相容性模型能解决总量生物量模型和分量生物量模型不兼容的问题,而且模型的预估精度高于经验模型;2)所建模型参数的决定系数 R2和模型偏差统计量,估计值的标准差 SEE、平均估计误差MPE、平均相对偏差 ME、平均相对偏差绝对值 MAE 分别为0.907~0.947,1.887~17.368,1.011%~2.703%,-4.937%~6.998%,5.408%~10.886%;3)对大兴安岭北部兴安落叶松天然林样木实测值进行统计分析,得到兴安落叶松天然林单木干材生物量占地上生物量的60.37%~76.80%,所占比例随年龄增加先增加再减小。树皮生物量占地上生物量的7.15%~20.11%,所占比例随年龄增加而减小;树枝生物量占地上生物量的8.51%~14.29%,所占比例随年龄增加基本呈现增加趋势;树叶生物量占地上生物量的5.12%~7.09%,在低林龄期时所占比例最大。  相似文献   
43.
内蒙古柠条生物量建模   总被引:1,自引:0,他引:1  
以内蒙古自治区的常见灌木种柠条(Caragana microphylla)为研究对象,基于大样本的生物量实测数据,利用非线性误差变量联立方程组方法,建立了单株水平的地上生物量模型及其相容的地下生物量模型和根茎比模型,并建立了基于平均植冠面积和密度或覆盖度的群落水平的总生物量模型。结果表明:植冠面积是影响单株生物量的首要因子,其次才是丛生枝个数;基于植冠面积和丛生枝个数的单株地上生物量模型,其确定系数能接近0.7,但地下生物量模型的确定系数要低些,还不到0.5;单株地上生物量和地下生物量模型的平均预估精度均能达到90%左右,总生物量的平均预估精度能达到92%以上,完全可用于内蒙古自治区范围内柠条灌木林的生物量估计。以单株总生物量模型为基础,直接推导出不同密度或覆盖度的群落总生物量模型,可为建立群落水平的灌木生物量模型提供借鉴。  相似文献   
44.
某轮式拖拉机在按欧盟法规ECE R10进行出口认证的电磁兼容性检测时,其窄带电磁辐射不合格。针对该问题,通过试验研究,频谱分析,找出了骚扰源,并对其重新进行了改进。经过试验验证,整改后的拖拉机窄带辐射完全符合标准要求,顺利通过了出口认证测试。  相似文献   
45.
self-(in)compatibility almond genotypes: A review   总被引:1,自引:0,他引:1  
To compile self-(in)compatibility almond genotypes, a review of 133 commercial cultivars of wide geographical origin was made. The information gathered from own and mainly published work will be useful for both grower's cultivar choice when planting and for breeder's cross design when planning. The almond S genotypes compiled were identified using five different methods: biological (pollination tests in the field and in the laboratory) and molecular (RNases, PCR and sequencing). In most cases, genotypes were assigned after combining more than one technique. Cultivars were classified into three categories: self-incompatible (99), self-compatible (16) and doubtful self-incompatible (18). The database is divided in 9 fields (name, origin, parentage, obtention year (crossing, selection or release), S genotype, technique used, reference, consensus genotype, and cross incompatibility group). A study of the 27 S alleles already identified and their geographical distribution within the cultivated almond is also presented. The study was divided into cultivars of known and unknown parentage and the distribution of S alleles frequencies was uneven among the 133 cultivars. S allele frequencies are related to geographical origin. Some alleles (S 1, S 5, S 7 and S 8) are more frequently observed than the others among cultivars of both known and unknown parentage. In the cultivated almond, the S f allele is only found in the Puglia region, Italy. The S f frequency is three times higher in cultivars released from breeding programmes than in cultivars selected by growers. From the 351 resulting possible genotypes by combination of the 27 S alleles identified only 20 CIG (0-XIX) have been established, which represents a small fraction of the whole genetic diversity of this polymorphic gene in almond.  相似文献   
46.
Dana  Michael N.  Ascher  Peter D. 《Euphytica》1985,34(2):237-244
Summary Discriminating styles (DS) in Petunia hybrida discriminate among incompatible pollen sources with pollen-mediated pseudo-self compatibility (PMPSC) similarly to those in Nemesia strumosa. Both species exhibit a single-locus gametophytic self-incompatibility system. Correlation of PMPSC to PSC level of the male was not universal and DS/PMPSC operated in heterozygous S genotypes. PSC levels of progenies generated from compatible or incompatible bud pollination were not significantly different from those of open-flower pollination of a DS plant with a given male, suggesting that DS did not select among male gametophytes for increased PSC.Scientific Journal Series Paper Number 13,077 of the Minnesota Agricultural Experiment Station.  相似文献   
47.
美国稻在水稻杂种优势利用中的地位   总被引:5,自引:0,他引:5  
对13个美国稻(A)与籼稻(H)、粳稻(K)的F1杂种优势的研究结果表明,A×H的各性状的杂种优势与K×H(亚种间)比较一致,但一般稍低于K×H,单株产量、单株穗数和主穗颖花数优势较强,且是可利用的杂种优势,株高也有较强的优势,但是非利用的杂种优势,单株产量的优势大小与美国稻的亲和性有密切关系;在A×K中,单株产量和单株穗数有较强的杂种优势,表现了与K×K较一致的趋势。千粒重无论在A×H或A×K中都表现了较低的正向优势。另外,根据试验结果提出了美国稻中的广亲和品种(WCVS)与籼稻杂交或美国稻与粳稻杂交均为水稻杂优利用中较好的高产组合模式,其中A×K更为切实可行。  相似文献   
48.
Summary Highly pseudo-self compatible (PSC) Nemesia strumosa plants were selfed and intercrossed to produce progenies of the F5 through F7 generations. Though high PSC progenies were obtained, none were truebreeding. Progenies from crossing inbred high PSC plants to low PSC plants consisted of either mostly low PSC plants or both low and intermediate plants. A backcross to the high PSC parent of a progeny from a low times high cross produced a family with a PSC frequency distribution skewed toward low PSC but with a few high PSC plants. These data may be explained if PSC genes at some or most loci are incompletely dominant to non-PSC genes and threshold numbers of PSC genes are required for PSC expression and for 100% PSC plants. Dominance may also occur at some loci. Although only a small number of genes may be required to produce a high PSC plant, the total number of PSC genes may be large.Scientific Journal Series Paper No. 11,676 of the Minnesota Agricultural Experiment Station.  相似文献   
49.
Intersubgeneric Crossability in the Genus Glycine Willd.   总被引:1,自引:0,他引:1  
In intersubgeneric crosses between wild perennial Glycine species of submenus Glycine and soybeans, Glycine max (L.) Merr., of subgenus Soja, all the putative hybrid pods aborted from 9 to 30 days after pollination (DAP). Spraying of 70 ppm gibberellic acid on hybridized gynoecia facilitated pod retention. Fluorescence microscopy revealed normal pollen germination and pollen tube growth in all the intersubgeneric crosses except in the G. cyrtoloba × G. max cross.  相似文献   
50.
J. D. Agnew 《Plant Breeding》1986,97(2):183-186
Self-pollination of 2f species of vandaceous orchids was followed by later embryo culture carried out to determine which species are self-compatible (SC) or incompatible (SI): 10 are SC, 1 are SI and the remaining:8 require further study. In the SI species, a few progeny could usually be recovered and these are interpreted as arising from mutation at the incompatibility locus (loci). The implications of the findings for current models of incompatibility are discussed.  相似文献   
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