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691.
R. A. Bustomi Rosadi Afandi Masateru Senge Kengo Ito John T. Adomako 《Paddy and Water Environment》2005,3(4):219-223
The objective of this research was to investigate the critical water content (θ
c) and water stress coefficient (K
s) of soybean plant under deficit irrigation. This research was conducted in a plastic house at the University of Lampung,
Sumatra in Indonesia from June to September 2000. The water deficit levels were 0–20%, 20–40%, 40–60%, 60–80%, and 80–100%
of available water (AW) deficit, arranged in Randomized Completely Block (RCB) design with four replications. The results
showed that the soybean plant started to experience stress from week IV within 40–60% of AW deficit. The fraction of total
available water (TAW) that the crop can extract from the root zone without suffering water stress (p) was 0.5 and θc was 0.305 m3 m−3. The values of K
s at p=0.5 were 0.78, 0.86, 0.78, and 0.71 from week IV to week VII, respectively. The optimum yield of soybean plant with the highest
yield efficiency was reached at 40–60% of AW deficit with an average K
s value of 0.78; this level of deficit irrigation could conserve about 10% of the irrigation. The optimum yield of soybean
plant was 7.9 g/pot and crop water requirement was 372 mm. 相似文献
692.
N. Hirota H. Kuroda K. Takoi T. Kaneko H. Kaneda I. Yoshida M. Takashio K. Ito K. Takeda 《Cereal Chemistry》2006,83(3):250-254
We examined the malting and brewing performances of a lipoxygenase‐1 (LOX‐1) null line of barley (Hordeum vulgare L.). The LOX‐normal malt and the LOX‐null malt were prepared from F4 populations derived from a single cross. We could not observe any major differences in the general malt characteristics between the two malts. A brewing trial was performed using these malts. The analysis of the wort and beer revealed that the absence of LOX‐1 had little effect on the general characteristics of the wort and beer. In contrast, beer made from the LOX‐null malt showed reduced levels of beer‐deteriorating substances, trans‐2‐nonenal (T2N), and trihydroxyoctadecenoic acid (THOD). In the sensory evaluation, well‐trained panel members recognized the significant superiority of the aged LOX‐null beer in terms of staleness. These results show that the LOX‐1 null barley line can be effectively used to improve the flavor stability of beer without changing the other important beer qualities. 相似文献
693.
Magnesium oxide nanoparticles induce systemic resistance in tomato against bacterial wilt disease 下载免费PDF全文
Bacterial wilt is a serious problem affecting many important food crops. Recent studies have indicated that treatment with biotic or abiotic stress factors may increase the resistance of plants to bacterial infection. This study investigated the effects of magnesium oxide nanoparticles (MgO NP) on disease resistance in tomato plants against Ralstonia solanacearum, as well as its antibacterial activity. The roots of tomato seedlings were inoculated with R. solanacearum and then immediately treated with MgO NP; the treated plants showed very little inhibition of bacterial wilt. In contrast, when roots were drenched with a MgO NP suspension prior to inoculation with the pathogen, the incidence of disease was significantly reduced. Rapid generation of reactive oxygen species such as O2?˙ radicals was observed in tomato roots treated with MgO NP. Further O2?˙ was rapidly generated when tomato plant extracts or polyphenols were added to the MgO NP suspension, suggesting that the generation of O2?˙ in tomato roots might be due to a reaction between MgO NP and polyphenols present in the roots. Salicylic acid‐inducible PR1, jasmonic acid‐inducible LoxA, ethylene‐inducible Osm, and systemic resistance‐related GluA were up‐regulated in both the roots and hypocotyls of tomato plants after treatment of the plant roots with MgO NP. Histochemical analyses showed that β‐1,3‐glucanase and tyloses accumulated in the xylem and apoplast of pith tissues of the hypocotyls after MgO NP treatment. These results indicate that MgO NP induces systemic resistance in tomato plants against R. solanacearum. 相似文献
694.
SUMMARY: Growth and reproduction of hatchery-reared Chinese white prawn Penaeus chinensis released in the Ariake Sea, Japan, were examined. Chinese white prawn grew rapidly, reaching a body length of 154 mm in males and 198 mm in females by November (219–229 days after hatching). Maximum body length of sampled individuals was 164 mm in males and 223 mm in females. Growth curve of the Chinese white prawn was fitted to the Pitcher and MacDonald's formula, Lt = 155.0{1 − e 2.925sin[2π(t − 16.151)/365] − 0.0623( t − 10.712) } for males and the logistic curve, Lt = 200.3/[1 + e (1.985–0.034 t ) ] for females (where Lt is the body length t days after release and t is the number of days after release). Females reached sexual maturity in late February and spawning occurred until April. Minimum size at ripe and spawned stages was 189 mm and 193 mm body length, respectively. 相似文献
695.
Zenta Nishio Hanaki Oikawa Takanobu Haneda Masako Seki Miwako Ito Tadashi Tabiki Hiroaki Yamauchi Hideho Miura 《Cereal Chemistry》2009,86(3):313-318
Reduced amylose wheat (Triticum æstivum L.) produces better quality noodles and bread less prone to going stale, while little is known about the relationships between amylose content and the quality of soft wheat baking products such as sugar snap cookies (SSC) and Japanese sponge cakes (JSC). Near‐isogenic lines developed from wheat cultivar Norin 61, differing in their level of granule‐bound starch synthase (Wx protein) activity, were used to produce wheat grains and ultimately flours of different amylose contents. These were tested with regard to their effect on soft wheat baking quality and solvent retention capacities (SRC). Amylose content was strongly correlated to cookie diameter (r = 0.969, P < 0.001) and cake volume (r = 0.976, P < 0.001), indicating that the soft wheat baking quality associated with SSC diameter and JSC volume were improved by an incremental increases in amylose content. Among the four kinds of SRC tests (water, sodium carbonate, sucrose and lactic acid), the water SRC test showed the highest correlation with amylose content, SSC diameter, and JSC volume. When the regression analysis was conducted between the nonwaxy and partial waxy isogenic lines that are available in commercial markets, only water SRC was significantly correlated to amylose content (r = –0.982, P < 0.001) among of four SRC tests. This suggests that, unlike udon noodle quality, high‐amylose content is indispensable in improving soft wheat baking quality, a process requiring less water retention capacity. 相似文献
696.
Zenta Nishio Yuri Miyazaki Masako Seki Miwako Ito Tadashi Tabiki Koichi Nagasawa Hiroaki Yamauchi Hideho Miura 《Cereal Chemistry》2011,88(2):189-194
The effect of growing environments of soft wheat on amylose content and its relationship with baking quality and solvent retention capacities (SRC) was investigated. Near‐isogenic soft wheat lines of Norin 61 differing in granule‐bound starch synthase (Wx protein) activity and grown in three different regions of Japan: Hokkaido (spring‐sown) for 2006 and 2007, Kanto (autumn‐sown), and Kyushu (autumn‐sown) for 2007 were evaluated. Spring‐sown samples produced grains of greater protein content (10.9–12.4%) than autumn‐sown samples (7.3–9.1%). In contrast, spring‐sown samples of 2007 with higher maturing temperature had lower amylose content (25.5% for Norin 61) compare to the autumn‐sown and spring‐sown samples of 2006 (27.6–28.4% for Norin 61). Amylose content was strongly correlated to sugar snap cookie (SSCD) diameter (r = 0.957–0.961; n = 10, all samples; P ≤ 0.001, r = 0.701–0.976; n = 7 partial waxy and nonwaxy samples; and Japanese sponge cake (JSCV) volume r = 0.971–0.993; n = 10; P≤ 0.001, r = 0.764–0.922; n = 7 partial waxy and nonwaxy samples), regardless of seeding season and growing conditions. The strength of the JSVC‐amylose relationship (slope) was similar among the three regions, whereas the strength of the SSCD‐amylose relationship was slightly weaker for spring‐sown samples and slightly stronger for partial waxy and nonwaxy autumn‐sown samples. Among of the four solvents (water, solutions of sodium carbonate, sucrose, or lactic acid), water‐SRC showed the greatest correlation to amylose content (r = –0.969 to –0.996; n = 10; P ≤ 0.001, r = –0.629 to –0.983; n = 7 partial waxy and nonwaxy samples), indicated that amylose content can be accurately estimated from the water‐SRC within the samples from the same grown environment. 相似文献