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61.
Ten ‘Russet Burbank’ potato clones collected from various geographical regions of the United States and Canada were evaluated for plant and agronomic characteristics for two years at Aberdeen, Idaho. Clonal differences were detected for emergence time, stem number per hill, expression of Verticillium symptoms, some measures of yield, and percentage of tubers with hollow heart. Eight of the ten clones were quite similar. Differences were slight or found only in a few characteristics. One clone, collected from northern Idaho, was similar to the homogenous eight clones in all respects except yield, which was probably due to chronic PVX infection throughout the trial period. Another clone, collected from New Brunswick, was distinct from all other clones and was markedly inferior with respect to many of the characteristics measured when grown in Idaho.  相似文献   
62.
Genetic improvement has been the principle contributor to productivity growth in almost all field crops. The Pacific Northwest (PNW) had the highest rate of potato yield growth combined with the least amount of varietal change in any specialized major field crop-producing region in North America. A coordinated potato variety development program, jointly funded by the USDA, the three land grant universities, and the potato industry in the PNW, was established in 1984. The program developed 17 new potato varieties during the 1989–2001 period, two of them are emerging as successful processing varieties. Ranger Russet, released in 1991, and Umatilla Russet, released in 1998, possess several desired quality and production traits. The most important of these traits is 20% higher processing yield than present varieties. Since their release, there has been significant increase in the percentage of potato area planted with these new varieties. The weighted average adoption rate of these new varieties in the PNW in 2000 was about 16% of the area planted with potato. This represents 32.5% of Washington’s potato acreage, 14.3% of Oregon’s potato acreage, and 9.0% of Idaho’s potato acreage. The benefit to investments in the PNW Potato Variety Development Program attributed only to the flow of benefits from the adoption of Ranger Russet and Umatilla Russet is estimated at over $104.3 million in year 2000 and projected to increase to $213.595 million in year 2014 and thereafter. Rate of return to investment is estimated at 35%.  相似文献   
63.
Previous research suggests that field greening of potato tubers can be minimized by planting seedpieces at an appropriate depth along with sufficient hilling to minimize exposure to sunlight. The appropriate planting depth and hilling practices to minimize field tuber greening have not been determined for newer cultivars. Two separate studies, each conducted for three years, are reported here. The first measured the effect of seedpiece planting depth on the yield, quality, and field greening tuber yield of ‘Russet Burbank’, ‘Frontier Russet’, and ‘Shepody’ potatoes. Seedpieces were handplanted in pre-formed hills at 8, 15, or 23 cm measured from the top of the seedpiece to the top of the hill. Planting at 23 cm resulted in significantly lower total yield compared with the 8- and 15-cm depths for Russet Burbank and Frontier Russet, but planting depth did not affect total yield of Shepody. U.S. No. 1 yield of Russet Burbank was not affected by planting depth, but U.S. No. 1 yield of Frontier Russet was significantly less at the 23-cm depth. For Shepody, the 8-cm depth caused a significant reduction in U.S. No. 1 yield compared with the 15-cm depth. Field greening tuber yield of Russet Burbank was significantly less at the 23-cm planting depth compared to 8 cm. For Frontier Russet and Shepody, planting at 15 or 23 cm resulted in significantly less field tuber greening compared to the 8-cm depth. The second experiment examined the effects of planting depth and hilling practices on yield, quality, and field tuber greening of Russet Burbank and Gem Russet potatoes. Six planting depth and hilling treatment combinations were used. Seedpieces were planted at a depth of either 8 or 15 cm, then hilled to either 15 or 23 cm at emergence or after plants had formed a rosette of leaves approximately 10 cm in diameter (post-emergence hilling). At-emergence hilling treatments had no effect on total or U.S. No. 1 yields of Russet Burbank compared with the 15-cm planting depth, non-hilled control. However, all post-emergence hilling treatments significantly reduced Russet Burbank total and U.S. No. 1 yields. Planting Russet Burbank at 8 cm and hilling to 23 cm at emergence, or planting at 8 or 15 cm and hilling to 23 cm post-emergence reduced field tuber greening of Russet Burbank. The effects of planting depth and hilling on Gem Russet total and U.S. No. 1 yields were less definitive than for Russet Burbank, and no treatments significantly reduced field tuber greening yield compared with the control.  相似文献   
64.
‘Alturas’, a late-maturing, high-yielding, russet potato cultivar with high tuber specific gravity, was released in 2002 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington. Originally selected for dehydration processing, its cold-sweetening resistance also makes it suitable for processing out of storage into french fries and other frozen potato products. Culinary quality is high, with larger tubers suitable for fresh market if heavily russeted skin is not essential. Alturas consistently produced greater total and U.S. No. 1 yields than ‘Russet Burbank’ and ‘Ranger Russet’ in southern Idaho trials. Across other western trial sites, total yields of Alturas have on average been 29% and 14% greater than Russet Burbank and Ranger Russet, respectively. Alturas is resistant to Verticillium wilt (Verticillium dahliae) and early blight (Alternaria solani). Compared with Russet Burbank and Ranger Russet, Alturas is less susceptible to corky ringspot and foliar and tuber infection by late blight (Phytophthora infestans). It also is less susceptible to tuber net necrosis and Fusarium dry rot than Russet Burbank, and is more resistant to common scab (Streptomyces scabies) than Ranger Russet. However, Alturas is more susceptible to infection by PVY and PVX than Ranger Russet. Total nitrogen application recommendations for Alturas are approximately 40% less than those for Russet Burbank. Alturas requires 15% to 20% more water during the growing season than does Russet Bur-bank.  相似文献   
65.
Bannock Russet, a late-maturing, long russet potato cultivar, was released in 1999 by the USDA-ARS and the experiment stations of Idaho, Oregon, and Washington. It is suitable for processing into french fries and other frozen products. Its attractive russeted skin and excellent culinary qualities also make it suitable for fresh market. Bannock Russet, in comparisons with Russet Burbank, has consistently produced greater U.S. No. 1 yields in trials conducted throughout southern Idaho. In other western trial sites, total yields of Bannock Russet have been comparable to or smaller than that of Russet Burbank, but its percentage of undersize and cull potatoes is consistently less. Bannock Russet is resistant to potato virus Y (PVY), Verticillium wilt, common scab, and leafroll net necrosis. It also has moderate resistance to early blight (foliar and tuber) andErwinia soft rot. With respect to other potato diseases/disorders, Bannock Russet’s level of susceptibility is similar to that of Russet Burbank; the exception being shatter bruise, with Bannock Russet displaying a greater susceptibility. Cultural management guidelines have been developed to minimize shatter bruise in Bannock Russet. Bannock Russet’s multiple disease resistances coupled with its low nitrogen requirement, make it a low-input cultivar that could significantly reduce growers’ production costs.  相似文献   
66.
Taylorella equigenitalis is a gram-negative coccobacillus and the causative agent of a transmissible venereal disease in horses known as contagious equine metritis. Outbreaks of contagious equine metritis have been documented in various countries since 1977, with the most recent discovery in the United States in December 2008. During disease occurrences, culturing semen samples for T equigenitalis before breeding may help to prevent transmission of this disease; however, little is known about the antimicrobial activity of equine semen extenders against the organism. The purpose of this study was to investigate the infectivity levels of T equigenitalis in three equine semen extenders inoculated with known concentrations of the organism. The semen extenders used for this study included INRA 96, E-Z Mixin BF, and VMDZ. In addition, Timentin was added to INRA 96 at three different concentrations (0.5, 1.0, and 1.5 mg/mL) to investigate possible synergistic effects of antibiotic supplementation of extenders. Results were based on the visual counting of the colonies on chocolate Eugon agar plates. Both INRA 96 (with added Timentin) and VMDZ (as supplied by the manufacturer) significantly reduced the numbers of T equigenitalis isolated from semen extenders as compared with INRA 96 (as supplied by the manufacturer) or the antibiotic free E-Z Mixin BF. Our findings indicate that INRA 96 (with added Timentin) or VMDZ may significantly decrease the growth of T equigenitalis in extended semen; however, it is also important to consider the possible effects of antibiotic supplemented extenders on sperm longevity and fertility in addition to eliminating specific pathogens in semen.  相似文献   
67.
The aim of this randomised, observer-blinded, crossover study was to compare the effects of six treatments, administered intravenously to six horses: saline and saline (S/S); detomidine and saline (D/S); detomidine and 5 μg/kg buprenorphine (D/B5); detomidine and 7.5 μg/kg buprenorphine (D/B7.5); detomidine and 10 μg/kg buprenorphine (D/B10); and detomidine and 25 μg/kg butorphanol (D/BUT). The detomidine dose was 10 μg/kg for all treatments in which it was included. Sedation was subjectively assessed and recorded on a visual analogue scale. Peak sedation, duration of sedation and the area under the curve (AUC) for sedation scores were investigated using a univariate general linear model with post-hoc Tukey tests (P<0.05). Peak sedation and duration of sedation were statistically significantly different between treatments (P<0.001). No sedation was apparent after administration of S/S. The AUC was significantly different between treatments (P=0.010), with S/S being significantly different from D/S, D/BUT, D/B5 and D/B7.5, but not D/B10 (P=0.051).  相似文献   
68.
Bentazon [3-(l-methylethyl)-(1H)-2,l,3-benzothiadiazin-4(3H)-one 2,2-dioxide] was applied at two rates to nine potato cultivars in the field, with or without a crop oil, to plant foliage at two different heights. Seven days after application of bentazon, foliar injury ranged from 0 to 36 percent depending on rate, cultivar, and plant height at the time of application. Of nine cultivars tested, Russet Burbank was the most susceptible to injury and Red LaSoda the least susceptible. A bentazon application rate of 1.12 kg a.i./ha, compared to a rate of 0.84 Kg a.i./ha, resulted in a biologically insignificant increase in foliar injury of two to four percent and a significant increase in weed control. The addition of crop oil to bentazon did not result in an increase of foliar injury, but increased the percentage of weeds controlled approximately two-fold. With one exception, application of bentazon to plants 8–15 cm in height resulted in less foliar injury than application to plants 20–30 cm in height. Application of bentazon to larger plants resulted in lower yield and quality. For most cultivars, the application of bentazon (1.12 kg/ha a.i.) and crop oil (2.3 L/ha) to 8 to 15 cm-tall potato plants resulted in no appreciable loss in potato tuber yield, while controlling 74–85 percent of broadleaf weeds.  相似文献   
69.
70.
Three potato cultivars (Russet Burbank, Norchip, and Gemchip) grown with nitrogen applied at three rates were stored at two temperature regimes (Treatment 1: 13 months at 10 CTreatment 2: 1 month at 10 C; followed by a 1 C decrease per week until tubers were 4 C; followed by 6 months at 4 C; followed by a 1 C increase per week until tubers were 10 C; followed by 3 months at 10 C). Tuber chemical components and potato chip appearance were measured at harvest and after 3, 6, 9, 11, 12, and 13 months; these measurements were performed within 24 hours of the time potatoes were removed from storage. Sugar responses (tuber glucose, fructose, sucrose) and potato chip appearance were affected by cultivar over time in both years and storage temperatures. Russet Burbank tubers displayed a significantly higher glucose forming potential and produced darker appearing chips, regardless of storage temperature or time in storage, compared to Norchip and Gemchip. Potatoes receiving a cold-storage treatment contained less sugar and produced lighter appearing chips after 12 months storage compared to tubers stored at a constant 10 C for 12 months. The linear association between tuber chemical components and potato chip appearance varied with storage temperature.  相似文献   
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