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71.
F. G. Gmitter Jr. X. B. Ling X. X. Deng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(6):785-790
Summary Triploid hybrid Citrus plants were regenerated by somatic embryogenesis in vitro from endosperm derived calli. A sequence of media formulations was used to induce and support proliferation of primary callus from endosperm, to induce embryogenesis from primary callus, and to allow embryo development leading to viable plantlets. Calli were induced from cellular endosperm of Citrus sinensis (sweet orange), C. Xparadisi (grapefruit), and C. grandis (pummelo) excised 12–14 weeks post-anthesis. Induction of embryogenesis from sweet orange and pummelo primary calli required gibberellic acid and double mineral nutrient concentrations. Embryogenesis was not induced from grapefruit calli in these experiments. Only sweet orange embryos developed sufficiently to allow plant regeneration. Triploid axillary buds were minigrafted onto etiolated diploid rootstock seedlings in vitro in order to transfer triploid regenerants to soil and the external environment. Triploidy (2n = 3x = 27) was observed consistently in all phases of regeneration and in recovered plants. These results demonstrate that triploid hybrid plant recovery from Citrus endosperm can overcome barriers to sexual hybridization resulting from apomixis.Florida Agricultural Experiment Station Journal Series No. R-00627 相似文献
72.
二倍体型与三倍体型卫氏并殖吸虫同工酶谱的发育变异及其分类学意义 总被引:3,自引:1,他引:2
采用生趣板状聚丙烯酰胺胶是民泳法分析比较了二倍体型与三倍体型卫氏并殖吸虫童虫、成虫的醛缩酶、已糖激酶和葡萄糖-6-磷酸脱氢酶的同工酶谱,结果显示2n型与3n型卫氏并殖吸虫在不同发育期之间及两型吸虫相应各发育期之间ALD、HK及G6PD同工酶谱均显著变异,变异表现为两种方式,一种是在同一个基因座位区的同工酶的酶带数目 相似文献
73.
对卫氏并殖吸虫卵,从形态上通过微机图象识别,计算出虫卵的数字特征:面积和周长。利用Fuzzy数学方法,建立对虫卵的隶属函数,由此鉴别虫卵的类型。 相似文献
74.
Shaoyun Lu Chuanhao Chen Zhongcheng Wang Zhenfei Guo Haihang Li 《Plant cell reports》2009,28(3):517-526
Eight somaclonal variants with enhanced drought tolerance were isolated from regenerated plants of triploid bermudagrass (Cynodon dactylon × Cynodon transvaalensis cv., TifEagle). Three of them (10-17, 89-02, 117-08) with strong drought tolerance were selected for investigations of physiological
responses to drought stress. Compared to the parent control, TifEagle, the somaclonal variants had higher relative water contents
and relative growth, and lower ion leakages in the greenhouse tests, while no difference in evapotranspirational water losses
and soil water contents was observed between the variants and TifEagle. The variants also had less leaf firing in the field
tests under drought stress. Superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activities decreased
gradually in responses to drought stress in all plants and exhibited negative correlations with ion leakage, indicating that
the declined activities of these antioxidant enzymes were associated with drought injury in the triploid bermudagrass. However,
CAT activities were significantly higher in all three variants than in TifEagle during drought stress. Two variants, 10-17
and 89-02, also had significantly higher APX activities than TifEagle before and during the first 4 days of drought treatments.
These two lines also showed higher SOD activities after prolonged drought stress. Proline, total soluble sugars and sucrose
were accumulated under drought stress in all plants and exhibited positive correlations with ion leakage. More proline and
sugars were accumulated in TifEagle than in the variants. The results indicated that higher activities of the antioxidant
enzymes in the variants during drought stress are associated with their increased drought tolerance. 相似文献
75.
杨树三倍体选育研究进展 总被引:26,自引:0,他引:26
杨树三倍体具有速生,纤维长等特点,是速生短周期纸浆材的首选树种,本文从发现树天然三倍体,人工培养杨树三倍体,特别是采用杂交,筛选天然2n花粉,人工诱导2n配子方法培育三倍体等方面,对杨树三倍体的育种研究现状进行了综述,指出了杨树三倍体育种的发育方向及意义。 相似文献
76.
Lycoris sprengeri Comes ex Baker is endemic to China. Reported in the present
paper are the chromosomes number and karyotypes for two wild populations of the species
from Anhui. ( 1 )Caishi population has a karyotype 2n=33=9st+21t+3T. The length of
chromosomes ranges from 5.58~9.15μm. The karyotype belongs to Stebbin’s (1971)
“4A”. (2)Longyashan populations have two karyotypes. The karyotype formula of the type
I is 2n=22=8st+14t, with chromosomes ranging from 6.88~9.15μm. The karyotype
belongs to “4A”. The karyotype formula of the type Ⅱ is 2n=22=1m+1sm+14st+6t,
with chromosomes ranging from 7.20~15.80μm. The karyotype belongs to “3B”. The
triploid type of L. sprengeri was discovered in Anhui for the first time. The karyotype 2n=22 =1m+1sm+14st+6t in diploid type of this species is here reported for the first time.The Robertsonian change plays a key role in karyotype evolution of Lycoris. 相似文献
77.
The young-ears of “Yugu No. 1”, a millet (Setaria italica (L.) Beauv. ) variety of good quality, high yielding and stress-resistance, were chosen to induce callus on N6 medium. After 3—5 times of subcultures, the callus was treated with colchicine (0.02%) for 48 hours and then transferred hack to subculture medium to restore growth, after which the callus was transferred to differentiation medium and subsequently, tetraploid plants were obtained. Through crossing, using tetraploid plants as female parent and diploid plant as male parent, 5 triploid plants were found among 2100 offspring plants. The triploid plants were fertilized with pollens from diploid plants. Among the plants developed from the seeds harvested on triploid plants, 9 kinds of trisomics (totally 283 plants) were identified according to chromosomal number and morphologic feature. Each kind of the trisomics has specific marker feature: (Figures in parentheses represent the number of plants obtained) Triplo-1 (52) has rolling leaves, Triplo-2 (18) is dark green, Triplo-3 (43) is bushy and has degenerated spikelets at the tip of panicles: Triplo-4 (58) has long bristle: Triplo-5 (16) has slender stalks: Triplo-6 (36) has twisted panicle neck; Triplo-7 (44) is semi-erect; Triplo-8 (8) has thick panicles; Triplo-9 (8) is pseudonormal (Similar with diploid of “Yugu No. 1”). 相似文献
78.
M. Lapidot D. Bar-Zvi V. Kagan-Zur Y. Mizrahi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(8):914-916
Independent spontaneous triploid tomato plants (Lycopersicon esculentum Mill.) were collected among diploid hybrids growing in commercial greenhouses. Ploidy levels were verified by counting chromosomes, and the donor of the double genome dose was determined by restriction fragment length polymorphism (RFLP) analysis. The TG101 probe, which is tightly linked to the Tm-2
a locus, revealed different restriction patterns between TMV-resistant and TMV-susceptible parent lines. The parent donor which provided two genomes to the triploid was identified by comparing the relative intensity of alleles in the triploid with that in the diploid. The results indicate that both parents can serve as a double genome donor. 相似文献