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981.
华西箭竹(Fargesia nitida)种子特征及其萌发特性   总被引:1,自引:1,他引:1  
赵春章  刘庆 《种子》2007,26(10):36-39
华西箭竹(Fargesia nitida)是大熊猫天然采食的主要竹种之一,由于开花习性独特,对其种子的研究报道还很少见。对华西箭竹种子的基本特征及不同温度下的萌发特性进行了研究。结果表明:华西箭竹种子长为(5.01±0.43)mm、宽(1.99±0.18)mm、厚(1.72±0.13)mm、千粒重(11.51±0.07)g;风干种子的化学组成:水分含量为(10.22±0.36)%、淀粉(74.52±0.57)%、粗蛋白(7.54±0.32)%、粗脂肪(3.71±0.17)%、可溶性糖(2.94±0.21)%、其他成分仅占(1.04±0.01)%。其种子萌发的适宜温度为20~25℃;低于20℃或高于25℃,种子的萌发率都会下降。  相似文献   
982.
G. Q. Zhang  Y. He  L. Xu  G. X. Tang  W. J. Zhou 《Euphytica》2006,149(1-2):169-177
Summary The results showed that the F1 genotype from the cross (Brassica napus cv. Zheshuang 758 × cv. Z-4115) had good response to embryogenesis, and their embryo yield and rate of plant regeneration reached 69.8 embryo/bud and 46.9%, respectively. Characters from the doubled haploid (DH) populations in B. napus were analyzed and it was showed that the means of each agronomic trait were between their parents, but they were nearer to the paternal in 6 agronomic traits (plant height, branch position, number of pods in the main raceme, length of pod, number of pods/plant and number of seeds/pod). The number of genes controlling each agronomic trait was analyzed based on the DH populations. The results showed that the number of genes controlling number of pods in the main raceme was the highest (15.6), and the least number of genes was involved for stem width (only 7.9). According to estimated coefficients of skewness and kurtosis of the traits tested, gene interaction was found to be absent for stem width, plant height, length of main raceme, number of primary and secondary branches, pod density in the main raceme and seed weight/plant. Complementary interaction was also observed in five agronomic traits (number of pods in the main raceme, length of pod, number of pods/plant, number of seeds/pod and 1000-seed weight). A significantly positive correlation was observed between seed yield/plant and four agronomic traits (length of main raceme, length of pod, number of pods/plant and 1000-seed weight). The experiment also showed that the erucic acid, glucosinolate, oil and protein contents of DH populations were 34.23%, 87.09 μmol/g, 44.09% and 42.67%, respectively. The numbers of genes controlling each quality trait were 7.8, 9.7, 9.4 and 8.7, respectively. Partial correlations between the seed quality traits and the agronomic characters of DH populations were analyzed. In this experiment, the partial correlations among seed quality traits were also analyzed and it was found that the oil content had a negative correlation with the other three seed quality traits.  相似文献   
983.
M. Mera    L. Beltran    H. Miranda    J. L. Rouanet 《Plant Breeding》2006,125(2):161-166
Thinner pod walls might contribute to increased yield potential and adaptation of lupins. Fourteen autumn‐sown genotypes of Lupinus albus L. were evaluated over 2 years at four sites in southern Chile. Pod wall proportion (PWP), pod wall specific weight (WSW) and five other pod‐related characters were measured to estimate their genetic variation, heritability across years and sites, and genotypic and phenotypic correlations among the characters. Ranges for PWP and pod WSW were 22.9−43.1% and 16.4−37.4 mg/cm2, respectively. PWP in cultivated L. albus was similar to that reported in L. angustifolius; however, specific weight was substantially lower. Highly significant genotypic effects were found for both characters. Broad sense heritabilities were high for PWP (0.63) and moderate for pod WSW (0.46). These characters were significantly correlated, more so genotypically (rg = 0.67) than phenotypically (rph = 0.36). Selection for low PWP should lead to lower pod wall thickness or density, both of which contribute to pod WSW. Nevertheless, selection for pod WSW could achieve further reductions, particularly if practised among low PWP materials.  相似文献   
984.
杂交水稻种子活力的渗透调节   总被引:1,自引:0,他引:1  
杂交水稻种子V优6号和汕优桂33经渗调剂在28℃预处理两天后,其发芽率、发芽势、活力指数和简化活力指数均比对照处理显著提高,尤其对低活力的汕优桂33更为明显,同时渗调剂处理的种子,α—淀粉酶、酸性磷酸酶和过氧化物酶的活性增强,其种子浸泡液的电导率,紫外吸收值比对照明显下降。  相似文献   
985.
Jai Gopal 《Euphytica》1993,72(1-2):133-142
Summary Six hundred and seventy six accessions of cultivated potato (Solanum tuberosum ssp. tuberosum) from 25 countries, were studied for flowering and fruiting behaviour under long days (12–14 h). Flowering intensity ranged from dropping of floral buds just after initiation to profuse blooming. The majority (58.3%) of the accessions bloomed profusely, though 20.4% of the accessions did not bloom at all. Weeks to flowering ranged from 6 to 15 and the majority (66.5%) of the flowering accessions bloomed within 8 to 9 weeks after planting. Duration of flowering ranged from 1 to 10 weeks and the majority (68.1%) of the flowering accessions bloomed for 1 to 4 weeks only. Twentythree per cent of the flowering accessions were completely male sterile. Maximum male fertility was 90% only. No berry setting was observed in 31.8% of the flowering accessions. Only 54.3 per cent of the accessions were found to be fertile in all respects and could be used both as male and female parents. Premature bud abscission was the major cause of sterility. Peru was the best source of profuse-flowering genotypes, Poland was the best source of early flowering genotypes and Mexico was the best source of long duration flowering and good berry setting genotypes. The results suggested that flower bud formation; the growth and development of mature flowers; weeks to flowering and duration of flowering are independent characters controlled by different genes of quantitative nature. Berry setting and duration of flowering were closely associated (r=0.95). Genetic as well as environmental factors interfered with the developmental process leading to flower production and berry setting at different times in different genotypes. The practical implications of these results for true potato seed production are discussed.Publication No. 1298, CPRI, Shimla.  相似文献   
986.
通过对“Ch型”谷子显性核不育的遗传研究,证实“Ch型”的不育性与“澳大利亚谷”的细胞质无关,其育性是受两对显性连锁基因Ms-和Rf-上位互作控制的。其中Ms是显性不育基因,Rf是显性上位基因,当二者共同存在时,显性上位基因能抑制显性不育基因的表达,从而使不育表现可育。这种由杂交而来,并能找到“恢复系”的显性核不  相似文献   
987.
渗透调节及其条件对番茄种子萌发的影响   总被引:4,自引:1,他引:4  
以-5.8~-15.6Mpa PEG—6000溶液处理番茄种子后,显著缩短了种子萌发所需天数。适合番茄种子的渗透调节处理浓度为250g/L左右;最少处理时间约需7天。同时,渗透处理的效果随温度而变化,处理温度以26℃左右为好。在18℃左右的较低温度条件下,利用渗透调节处理可以获得较大的促进萌发效果。  相似文献   
988.
研究了不同贮藏条件下半红赞皇大枣的采后生理变化和贮藏效果。结果表明,赞皇大枣属于非呼吸跃变型果实;在贮藏过程中Vc含量逐渐降低,乙醇和MDA含量前期缓慢上升、后期上升加快,PG酶和淀粉酶活性逐渐降低。与冷藏相比,气调贮藏对保持枣果品质效果更好。  相似文献   
989.
A. Elgersma 《Plant Breeding》1990,105(2):117-125
In perennial ryegrass seed yield is low and unreliable and little is known about the seed-yielding capacity of different cultivars. Therefore, genetic variation for seed yield was studied for therefore, genetic variation for seed yield was studied for three years at two locations. Twelve trials consisting of drilled plots of nine diploid, late-flowering cultivars in four replications were harvested for seed. Significant gentic differences for seed yield and seed weight weight were detected. The ranking of the cultivars for seed yield differed from that for seed weight. The levels of seed yield and seed weight were affected by such environmental factors as year, soil type and crop production year, but interactions of these factors with cultivars were generally not significant. Variation in seed yield was more related to variation in seed number than to variation in seed weight. There were no significant cultivar differences for yield stability. The highest yielding cultivar was superior over a wide range of environments and the seed yield of the poorest cultivar was on average only 64% of that of the best cultivar.  相似文献   
990.
G. Ladizinsky 《Euphytica》1985,34(2):539-543
Summary Seeds of the cultivated lentil are capable of germinating shortly after maturation. The seed dormancy of wild lentil species is due to a hard seed coat. In crosses between the cultivated species L. culinaris and its wild progenitor L. orientalis the hard seed coat of the wild species was controlled by a single recessive gene in homozygous condition. In a cross between the wild species L. ervoides and L. culinaris the hard seed coat of L. ervoides was controlled by a single dominant gene. The significance of the genetics of seed coat hardness in the domestication of lentil is briefly discussed.  相似文献   
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