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41.
Aurielle S. Medeiros Mércia V. F. dos Santos Márcio V. da Cunha Alexandre C. L. de Mello Djalma E. Simões Neto Osniel F. de Oliveira James P. Muir Jose C. B. Dubeux Jr André E. dos Santos 《Grass and Forage Science》2023,78(1):161-172
The use of legumes is an important strategy for animal feeding, especially during the dry season. The aim was to evaluate the effect of planting densities (40,000; 15,625 and 10,000 plants ha−1) and harvest heights (20 and 40 cm) on the morphology, accumulation and survival of Desmanthus (Desmanthus pernambucanus [L.] Thellung), cultivated in subhumid tropical region, as well as to estimate the repeatability of the evaluated characteristics and the optimal number of measurements. The treatments were randomized in blocks, with subdivided plots and four replicates. Planting densities were evaluated in the plots and the harvest heights in the subplots. Eight harvests were carried out with an interval of 84 days. Morphological and productive characteristics and survival were evaluated. Cultivation under density of 40,000 plants ha−1 produced taller plants, with higher leaf area index (LAI = 0.98), light interception (LI = 49%), individual accumulations (18.8 g DM plant−1) and by area (576.5 kg DM ha−1 harvest−1), although resulting in reduced plant stand (66%). Harvest heights do not affect accumulation and survival. It is possible to reduce the number of measurements for stem diameter, number of leaflets per leaf (R2 = 95%), plant height, canopy diameter, LAI, LI, leaf length and width, number of leaves per branch, branch diameter and LBR (R2 = 90%), optimizing resources for future research. Desmanthus has potential for use in protein banks, being harvested in the rainy season, conserved and supplied in addition to animals, but plant growth is minimal during the dry season under rainfed conditions. 相似文献
42.
我国木薯产业的发展趋势与市场分析 总被引：1，自引：0，他引：1
对我国的木薯种植,木薯淀粉(变性淀粉),木薯酒精行业的发展现状进行阐述,展望其发展趋势。 相似文献
43.
44.
苦瓜(Momordica charantia)具有丰富的营养价值和药用价值。由于耕地面积有限,苦瓜连作现象严重,根结线虫对苦瓜的为害逐年加重,严重影响苦瓜的产量和品质。针对海南省苦瓜根结线虫病的危害、传播途径、发生规律以及栽培特点,总结提出适合海南省苦瓜根结线虫病的防治对策,以期为海南苦瓜的安全生产提供技术支持。 相似文献
45.
通过采用测定200只壶天山羊的体尺体重,统计66胎产仔情况、屠宰6只成年羊,将8只成年杂交羊(壶天羊×马头羊)和50只成年壶天羊作对比等办法,从而真实系统地总结了该山羊的各项生产性能.对以"七化四结合"为主要内容的山羊生态养殖关键技术进行了研究,提出了"羊→沼→稻(菜或草)"生产模式和"企业 农户"的经营模式. 相似文献
46.
47.
A computer‐based water budget technique was developed considering the land gradient [{vertical interval between two adjacent field bunds (levees)=20 cm} ÷ the distance between the bunds] and paddy field bunds (viz. 16, 18, 20, 22, 24 cm) in its formulation for computing daily runoff from coastal paddy areas in India. The inputs used in the water budget technique consist of limited meteorological data that are easily available in India. The water budget technique was validated with the modified curve number method and the measured data collected during 2001 in a coastal paddy area of Orissa (east coast of India close to Bay of Bengal), India and its superiority was found. In most of the cases (barring a few events of 16 cm and 18 cm paddy field bunds for the water budget technique), statistically both methods differed significantly from each other while generating daily runoff. The estimate of the surface drainage coefficient (the amount of excess surface runoff water to be drained from the crop field during a 24‐hour period) for a 5‐year return period was computed as 100 mm day−1 (taking the 22 cm paddy field bund) and 109 mm day−1 in case of the water budget technique and modified curve number method, respectively. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
48.
《农业科学学报》2019,18(8):1726-1736
Mango is an important cash crop in the tropics and subtropics. Determining the yield gap of mango and production constraints can potentially promote the sustainable development of the mango industry. In this study, boundary line analysis based on survey data from 103 smallholder farmers and a yield gap model were used to determine the yield gap and production constraints in mango plantations in the northern mountain, central valley and southern mountains regions of Tianyang County, Guangxi, China. The results indicated that the yield of mango in three representing regions of Tianyang County,Northern Mountains, Central Valley and Southern Mountains, was 18.3, 17.0 and 15.4 t ha~(–1) yr~(–1), with an explainable yield gap of 10.9, 6.1 and 14.8 t ha~(–1) yr~(–1), respectively. Fertilization management, including fertilizer N, P_2O_5 and K_2O application rates, and planting density were the main limiting factors of mango yield in all three regions. In addition, tree age influenced mango yield in the Northern Mountains(11.1%) and Central Valley(11.7%) regions. Irrigation time influenced mango yield in the Northern Mountains(9.9%) and Southern Mountains(12.2%). Based on a scenario analysis, the predicted yield would increase by up to 50%, and fertilizer N use would be reduced by as much as approximately 20%. An improved understanding of production constraints will aid in the development of management strategy measures to increase mango yield. 相似文献
49.
以穴宽为优化目标的大蒜栽植机关键机构运动仿真及优化设计 总被引：1，自引：0，他引：1
为了优化适合大蒜栽植机关键机构的工作参数,研究了水稻插秧机分插机构的结构特点,以穴宽作为栽植质量的综合指标,建立了表征穴宽与大蒜栽植机的摇杆式分插机构各参数关系的数学模型。利用ADMAS软件的模型等效仿真功能分析了影响穴宽的因素,利用MATLAB软件对影响穴宽的因素进行了优化计算,优化结果显示理想穴宽与实际穴宽的误差为1.3×10~6mm,说明优化后的分插机构的工作参数符合大蒜栽植农艺需求,研究结果为自走式大蒜栽植机其他关键部件的设计提供了理论依据。 相似文献
50.
沿海沙质海岸木麻黄造林技术 总被引：1，自引：0，他引：1
阐述了木麻黄造林、更新以及低效林改造技术等方面内容,沿海防护林的营造需因地制宜,从树种选择、密度控制、结构调控、土壤管理等综合措施入手,才能提高林分的集约水平,形成良好的防护效果。 相似文献