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71.
72.
通过繁殖实践和组织学切片,研究了一龄金鱼的性成熟及生殖力情况。结果表明,繁殖季节的一龄金鱼性腺已发育成熟,雌性个体中卵巢已发育到了第Ⅳ期,主要由Ⅳ时相卵母细胞组成,雄性个体精巢已发育到第Ⅴ期,精细小管中已布满成熟的精子;在自然和人工环境下,一龄金鱼能自行产卵受精并产生存活后代,证明一龄金鱼能够达到性成熟,在此2种条件下并都能够自行繁殖后代。另外,对金鱼产生的单倍体卵子的质量和直径分别与红鲫产生的单倍体卵子及四倍体鲫鲤产生的二倍体卵子的质量和直径进行比较,结果表明,卵子的质量及直径与卵子的倍性存在正向相关关系。 相似文献
73.
The present study evaluated the individual plants reaction of F2 hybrid generation of C. annuum: ATZ1 × PO and ATZ1 × CDT as well as two interspecific hybrids: C. frutescens × C. annuum ATM1 and C. frutescens × C. chinense on androgenesis conditions in in vitro anther cultures. The experiment was carried out following a modified method of Dumas
de Vaulx et al. (Agronomie 1:859–864, 1981). There were demonstrated clear differences in the effectiveness of androgenesis
both between the pepper hybrid forms as well as among individual plants of all the genotypes tested. The highest effectiveness
of androgenic embryos development was observed for the cultivated form of C. annuum: (ATZ1 × PO)F2. Anthers of most of the plants of this hybrid produced embryos at the level higher than 5%, while in anther cultures of the
second C. annuum hybrid (ATZ1 × CDT)F2 almost 3-fold fewer embryos and plants were produced. Anthers isolated from flower buds of interspecific hybrids formed much
lower number of embryos. A positive reaction was recorded for five hybrid plants of (C. frutescens × C. annuum ATM1)F2, while in case of (C. frutescens × C. chinense)F2 androgenic embryos were obtained from anthers of two plants. Only in the case of a one of these plants did the effectiveness
of androgenesis exceed 5%. The ploidy level of the regenerants was determined by flow cytometry. Among the regenerants there
were observed both haploid forms and the plants with the diploid number of chromosomes. 相似文献
74.
Nadeem Khan Shujun Zhou M. S. Ramanna Paul Arens Jeronimo Herrera Richard G. F. Visser Jaap M. Van Tuyl 《Euphytica》2009,166(3):399-409
Ploidy level and intergenomic recombination was studied in interspecific hybrids between Longiflorum × Asiatic lilies (LA
hybrid) backcross to Asiatic parents in order to assess the possibility for analytic breeding in lily. By backcrossing the
diploid (2n = 2x = 24) F1 interspecific hybrid between Longiflorum × Asiatic lilies to Asiatic parents, 104 BC1 progeny plants were produced.
Among these, there were 27 diploids, 73 triploids (2n = 2x = 36) and 4 aneuploids (2x − 1, 2x + 2 or 2x + 3). In addition, by backcrossing triploid BC1 (LAA) plants to diploid Asiatic parents in 2x − 3x and reciprocal combinations, 14 diploid BC2 progenies were produced. Genomic in situ hybridization (GISH) was performed to
study the intergenomic recombination and karyotype composition. GISH indicated extensive intergenomic recombination among
the chromosomes in LA hybrids. A large number of Longiflorum chromosomes were transmitted to the BC1 progenies from LA hybrids.
However, very few Longiflorum chromosomes were transmitted from the BC1 triploid (LAA) plants to the BC2 progenies. The occurrence
of diploid plants in the BC progenies of LA hybrids has opened the prospects of analytic breeding in lilies. In this approach,
the selection of superior genotypes can be carried out at the diploid level and polyploid forms are synthesized from superior
diploid parents. The advantages of analytic breeding are evident: (a) a maximum level of heterozygosity can be attained in
the synthetic polyploids and (b) introgression can be achieved with a minimum of linkage drag. Based on GISH results the potential
application of analytic breeding in lily allopolyploids has been discussed. 相似文献
75.
为利用分子标记辅助选择技术选育抗旱高产小麦品种提供基础,以小麦旱选10号/鲁麦14 DH群体为材料,在干旱胁迫及正常灌溉两种水分条件下于2010年和2011年考察小麦主茎结实小穗数,通过采用基于混合线性模型的复合区间作图法分析其QTL,研究控制小麦结实小穗数的数量性状基因。共检测到7个加性QTLs和2对上位性QTLs。加性QTL的LOD值介于2.56~5.08之间,分别位于2D、4A、6A和6B染色体上,对表型变异的贡献率为7.19%~13.65%;上位性QTL的LOD值分别为5.24和5.47,分别位于3A和6B与4B和5B染色体上,对表型贡献率分别为13.71%和17.93%。其中QFns-6A-2于2010年正常灌溉和2011年两种水分条件下均被检测到,可用于分子标记辅助育种。 相似文献
76.
77.
玉米杂交诱导单倍生殖(单倍体)选育自交系技术规范(暂行版) 总被引:8,自引:4,他引:4
汇总国内外单倍体育种研究理论与经验,经美国著名单倍体育种家张铭堂指导,组装集成出本规范,供试用参考。本规范制定了杂交诱导单倍生殖方法选育自交系的基本操作程序,将单倍体杂交诱导、子粒鉴选、植株确认、自然与人工加倍及双单倍体获得5个环节作出技术规定。在每个环节都还有技术关键(特别是人工加倍等多属商业机密范畴)在试用与待熟化。经多年实践验证,按此规范程序,只需2~3个生育世代即可批量选育出遗传高度纯合自交系。 相似文献
78.
植物游离小孢子培养技术研究进展 总被引:1,自引:0,他引:1
利用植物游离小孢子培养获得单倍体植株,进而自然或人工加倍获得纯系已成为现代育种技术中的一个重要手段.它可以缩短育种年限,加速育种进程,降低误选,是近年来育种方面的研究热点.在查阅已建立起游离小孢子培养系统的植物种类的基础上,综述了影响植物游离小孢子胚胎发生的因素方面的研究进展,包括材料的基因型、材料的生长环境、小孢子的发育阶段、材料的前处理、小孢子的培养密度、培养基类型及组成成分和培养条件,与在游离小孢子培养中存在的问题等,以期为花卉游离小孢子的培养提供借鉴. 相似文献
79.
提高小麦×鸭茅状摩擦禾杂交组合的小麦单倍体植株成苗率的探索 总被引:1,自引:1,他引:0
法国小麦和中国小麦杂交的后代和鸭茅状摩擦禾(父本)杂交,授粉1 d后用100 mg/L 2,4-D蘸穗处理,12~14 d取单倍体幼胚培养。结果表明,仅培养于1/2 MS培养基上,成苗率为78.01%;而根据幼胚的发育状态,先将发育较完善的幼胚直接接种在1/2 MS培养基上,将发育不良的幼胚先接种于1/2 MS+2 mg/L 2,4-D的培养基上进一步养育幼胚,3~4 d后再将其转入1/2 MS培养基中,此法的成苗率为93.22%,较前者的成苗率提高了15.21个百分点。 相似文献
80.