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1.
咖啡黑小蠹的发生规律及药剂防治研究   总被引:1,自引:0,他引:1  
咖啡黑小蠢是近年在兴隆华侨农场严重危害中粒种咖啡的重要害虫。据1989年对4—5年生咖啡树调查,植株受害率100%,枝条受害率29.7—82.5%,虫害枯枝率7.65—17.8%。该虫以雌成虫钻蛀咖啡枝条为害,幼虫和成虫取食蛀道壁上的真菌菌丝。田间种群数量通常在3月上旬开始剧增,3月中下旬为高峰期,7月至10月田间虫口极少,11月以后逐渐有虫口及虫枯枝出现。温度是影响虫口波动的主要因素。2.5%溴氰菊酶、25%杀虫双、40%乐菊酯各兑水1000倍对成虫直接触杀效果显著,死亡率均为100%。48%乐斯本、40%氧化乐果400—800倍液等12种杀虫剂田间喷雾对咖啡枝条蛀洞内的成虫、蛹、幼虫防效均不明显。  相似文献   
2.
Among the most damaging root-knot nematode species, Meloidogyne exigua is especially common in Latin America and constitutes a major agronomic constraint in all major coffee-growing ( Coffea arabica ) areas. Growing nematode-resistant coffee represents the most promising option for control of the pest. The present study aimed to determine the mode of inheritance of the M. exigua resistance transferred into C. arabica from a related species, Coffea canephora , and to identify associated molecular markers. Segregation data analysis of F 2 progeny derived from a cross between the resistant introgression line T5296 and the susceptible accession Et6 showed that the resistance to M. exigua is controlled by a simply inherited major gene (designated the Mex -1 locus). The gall index distribution exhibited by the F 2 individuals suggested incomplete dominant expression. Fourteen AFLP markers were found associated with the resistance to M. exigua and a localized genetic map of the chromosome segment carrying Mex -1 was constructed. Furthermore, the association of the identified AFLP markers with Mex -1 was confirmed by analysis of a set of genotypes involving 28 introgression Arabica lines either resistant or susceptible to M. exigua in field conditions. These results represent an important starting point to enhance backcross breeding programmes and to perform an early selection of resistant seedlings.  相似文献   
3.
总结2010年以来云南河口民族地区小粒种咖啡技术创新亮点,分析认为:近年研究制定的《河口小粒咖啡综合技术规范》(DG5325/T 5.1-5.6—2013)标准,规范了本地区小粒种咖啡栽培技术;试验筛选出的高抗锈良种CIF7963(6),加快了本地区良种化进程;“水压自动补偿”灌溉系统,解决了本地区传统灌溉问题;对传统湿法加工实施背压式热风穿透风干燥技术(设备)改造,改变了传统上利用水泥晒场自然晾晒咖啡豆。这些创新亮点促进了本地区小粒种咖啡产业的可持性发展。  相似文献   
4.
The distribution of the plant-parasitic nematodes Pratylenchus coffeae sensu lato and Meloidogyne spp. were studied in two plots, one in Guatemala ( P. coffeae and M. paranaensis ) and the other in Costa Rica ( P. coffeae and M. exigua ). The quantity of nematodes per g fresh weight root were counted for each coffee tree sampled. The distributions were aggregated, and generally fitted well to negative binomial distributions. Population aggregation was greater when a smaller number of nematodes were involved, suggesting that initial colonization develops in foci. Analyses of the relationships between population levels of the species suggested that there was competition between Pratylenchus coffeae and Meloidogyne spp. This competition was expressed differently depending on the relative population density of the different species.  相似文献   
5.
The export of nitrogen (N) from senescent plant parts is important for the efficient use of this macronutrient. The objective of this study was to establish correlations among the photosynthetic pigment content, total N, and the photosynthetic variables with the SPAD‐502 readings in Coffea arabica leaves. Correlations were established among the chlorophyll content, N content, and chlorophyll a and b with SPAD‐502 readings taken on coffee leaves at different months. The results show that all variables decreased with time. However, correlation increased linearly with N doses. Total chlorophyll presented a direct linear correlation with readings of the portable chlorophyll meter. The SPAD readings have shown to be a good tool to diagnose the integrity of the photosynthetic system in coffee leaves. Thus, the portable chlorophyll SPAD‐502 instrument can be used to evaluate the N status and can also help to evaluate the photosynthetic process in coffee plants.  相似文献   
6.
In areas where traditional multistrata coffee systems have been transformed to systems with patchy or no shade at all, often dependent on high chemical inputs, ecological and socioeconomic degradation has become an increasing issue. During the 1990s, rising environmental and health concerns have promoted the interest in organic production systems and their environmental services for natural resource conservation. This study compared productivity, profitability, producer-defined constraints, and goals and research priorities between ten individually paired organic and conventional coffee farms in Costa Rica. Although five of the organic farms matched or exceeded the production of their conventional counterparts, the three-year mean yield of the organic farms as a group was 22% lower than that of the conventional farms. However, excluding organic certification costs, mean variable costs and net income (NI) were similar for both groups, mainly because organic price premiums received by the farmers compensated for lower yields. If current organic certification costs are included, the price premiums paid to organic producers would have to increase to 38% in order to equal the NI from conventional coffee. Conventional farmers indentified low and unstable prices as the main constraints to sustained production and stated further intensification of production as their main goal. In contrast, the key issues for future development of the organic group centered on farm diversification, agroecological self-sufficiency, and agronomic practices that permit organic farm management. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
7.
During most of its cultivation in Central America, coffee (Coffea arabica L.) suffered few serious pest problems. However, over the past three decades, three factors contributed to significantly increase pest levels and losses: the recent introduction of new pests; more favorable conditions for existing pests, diseases, and weeds due to lower shade levels; and secondary pest problems caused by pesticide use. The strategy of maximizing coffee production with pest control dominated by synthetic pesticides has not only increased yields substantially, but also production costs, pesticide resistance, and both human health and environmental risks. An analysis of the response of the food web in coffee plantations to varying levels of light and humidity associated with different shade levels provides the basis for identifying the optimum shade conditions which minimize the entire pest complex and maximize the effects of beneficial microflora and fauna acting against it. These optimum shade conditions for pest suppression differ with climate, altitude, and soils. The selection of tree species and associations, density and spatial arrangement, as well as shade management regimes are critical decisions for shade strata design. Site-specific knowledge of the seasonal food web dynamics permits growers to determine the appropriate seasonal shade management in order to further suppress pest levels. For example in a low-elevation dry coffee zone, 35 to 65% shade promotes leaf retention in the dry season and reduces Cercospora coffeicola, weeds, and Planococcus citri; at the same time, it increases the effectiveness of microbial and parasitic organisms without contributing to increased Hemileia vastatrix levels or reducing yields. In these conditions, shade should be at a maximum early in the dry season and at a minimum by the middle of the rainy season. Further research is needed on: the effects of individual tree species on the food web; the role of canopy architecture for coffee vigor, photosynthesis, leaf drying, pest susceptibility, and pruning regimes; and on simple observation methods and decision criteria for farmer management of tree-coffee-food web interactions. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
8.
对引进保存的个咖啡种质进行种质特性和适应性研究及评价;对用部分种质的基因型作有性杂交,164获得份不同杂交组合种子实生苗材料进行筛选;推广小粒咖啡卡蒂莫(15CIFC7963F6)生产种植6 984hm2,取得显著经济效益。  相似文献   
9.
云南小粒咖啡优良品种比较试验及丰产栽培示范   总被引:2,自引:0,他引:2  
以德宏热带农业科学研究所咖啡种质库选出的13个小粒咖啡品种为材料,在云南省4个不同的生态类型区建立咖啡优良品种比较试验区和丰产栽培试验区,以验证各品种的生长、产量和品质等优良特性,和在不同生态类型区的稳定性,试验结果筛选出CIFC7963、28号可在云南适宜植区大规模种植;T8667、T5175、CatimorP88、CatimorP128等4个品种可以扩大种植。景洪试验点年均气温高(22.4℃),超过小粒种咖啡对最适年均温(19~21℃)的要求,不适宜种植小粒种咖啡。  相似文献   
10.
针对云南丘陵山区小粒咖啡人工采收成本高、大型机械采收困难等问题,设计了手持振动梳刷式小粒咖啡采摘装置。通过建立果树-机械收获动力学模型和多体动力学仿真,得到振幅的稳态响应表达式,并确定了振动部件和梳刷部件的结构参数。利用ADAMS建立了果树-机械刚柔耦合模型,采用广义力与传感器函数控制的方法进行单因素仿真试验,分析了频率、梳齿间距和偏心块夹角对小粒咖啡收获效果的影响规律。以频率、梳齿间距和偏心块夹角为试验因素,采净率、采青率和损伤率为试验指标,进行二次回归正交旋转组合试验,结果表明:对采净率和采青率的影响因素重要性依次为频率、梳齿间距、偏心块夹角;对损伤率影响因素重要性依次为梳齿间距、频率和偏心块夹角。当频率为26Hz、梳齿间距为32mm、偏心块夹角为22.5°时,采摘机工作性能最佳,经试验验证,此时采净率为91.35%,采青率为8.46%,损伤率为4.15%,满足小粒咖啡收获技术要求。  相似文献   
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