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51.
不同灌水量对饲料玉米耗水特性和生物量的影响   总被引:1,自引:0,他引:1  
为了研究不同灌水量对饲料玉米耗水特性和生物量的影响,采用卷盘式喷灌的灌水方式,在内蒙古鄂尔多斯市鄂托克前旗进行田间试验。结果表明:总体来说随着灌水量的增加,饲料玉米的耗水量、耗水强度、株高、产量和水分生产率都有不同程度的增加;其中灌水定额为60mm的处理分枝期的耗水强度最大为4.31mm/d;在灌水量低于45mm时,增加灌水量对于产量和水分生产率的影响十分明显;而灌水量为60mm处理,相对于45mm处理来说产量和水分生产率增加甚微。从经济、节水、增产考虑,建议饲料玉米苗期可适当增加灌水量,其他生育期可取45mm的灌溉制度。  相似文献   
52.
本文从COD,NH3-N,TN,TP四个方面分析了空心菜、水稻、水葫芦三种饲料植物水生环境处理猪场厌氧废液的水质变化规律.结果表明,三种饲料植物水生环境对猪场厌氧废液的COD去除率:空心菜>水稻>水葫芦;对NH3-N的去除率:水葫芦>水稻>空心菜;对TN的去除率:空心菜>水稻>水葫芦;对TP的去除率:水葫芦>空心菜>水稻.饲料植物对藻有抑制作用,藻对NH3-N和TN有去除作用,对照系统中由于藻的出现,增强了系统对NH3-N和TN的去除效果,因此在NH3-N和TN两指标上出现对照系统好于饲料植物处理系统.  相似文献   
53.
Copper (Cu) mine tailings, because of their high content of heavy metals, are usually hostile to plant colonization. A pot experiment was conducted to determine the tolerance of four forage grasses to heavy metals in Cu mine tailings and to examine the variation in the microbial functional diversity of soils from the tailing sites in southern China. All the four grass species survived on Cu mine tailings and Cu mine tailing-soil mixture. However, on pure mine tailings, the growth was minimal, whereas the growth was maximum for the control without mine tailings. The tolerance of grasses to heavy metals followed the sequence: Paspalum notatum 〉 Festuea arundinaeea 〉 Lolium perenne 〉 Cynodon daetylon. The planting of forage grasses enhanced the soil microbial biomass. The Biolog data indicated that the soil microbial metabolic profile values (average well color development, community richness, and Shannon index) of the four forage grasses also followed the sequence: P. notatum 〉 F. arundinaeea 〉 L. perenne 〉 C. daetylon. Thus, P. notatum, under the experimental conditions of this study, may be considered as the preferred plant species for revegetation of Cu mine tailing areas.  相似文献   
54.
三峡库区沿江退耕还林地种草效果初探   总被引:1,自引:0,他引:1  
在农区退耕早熟梨地种植豆科、禾本科牧草,通过测定它们的盖度变化、产草量和越夏率,比较分析了果园适宜种植牧草品种及应注意的问题,并讨论了重庆低海拔沿江农区发展草业生产的前景。  相似文献   
55.
生物技术在牧草育种中的应用   总被引:2,自引:0,他引:2  
综述了近20年来生物技术在牧草育种中的主要研究进展.包括植物细胞和组织培养在牧草种质资源保存、体细胞杂交和胚抢救技术在克服种间杂交障碍、分子标记和转基因技术在牧草品质改良、抗病虫、抗逆性育种和作为生物反应器等方面的应用前景.  相似文献   
56.
石灰岩山区果园生草对果树根系生态系统的效应   总被引:3,自引:0,他引:3  
石灰岩山区果园生草可以提高生长季土壤含水量 ,稳定周年地温 ,提高土壤基础养分含量 ;改善土壤物理性能 ,从而促进果树根系发育。无芒雀麦和鸭茅草是石灰岩山区果园比较适宜的优良草种  相似文献   
57.
Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs (Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs ($ ha?1 calculated as change in operating profit divided by unit change of the trait) for additional DM produced in different seasons of the year in four regions. The EV of early spring DM was consistently high across all regions, whereas EV for late spring DM was moderate to low. Genotype × environment analysis revealed significant reranking of DM yield among ryegrass cultivars across regions. Hence, separate performance values (PVs) were calculated for two mega‐environments and then combined with the corresponding season and region EV to calculate the overall EV for twenty‐three perennial ryegrass and fifteen short‐term ryegrass cultivars. The difference in operating profit between the highest ranked and lowest ranked perennial ryegrass cultivar ranged from $556 ha?1 to $863 ha?1 year?1 depending on region. For short‐term ryegrasses used for winter feed, the corresponding range was $394 to $478 ha?1 year?1. Using PV for DM yield, it was estimated that plant improvement in perennial ryegrass has added $12–$18 ha?1 year?1 (depending on region) operating profit on dairy farms since the mid‐1960s.  相似文献   
58.
Invasive grasses (especially Setaria pumila (Poir.) Roem. et Schult) increasingly threaten meadows and pastures as a consequence of human impact and climate change. We conducted a study in 2012 and in 2013 to better understand the growing cycle and the influence of S. pumila on forage quality of lowland meadows. We observed a rapid increase of S. pumila presence and phytomass on the southern side of the Alps across the growing season. We measured (i) above‐ground phytomass, with a modified Corral‐Fenlon method; (ii) botanical composition using the linear point quadrat method; and (iii) grassland chemical composition by NIRs (near‐infrared spectroscopy) analyses. To test the hypothesis that S. pumila summer growth is related to specific climatic conditions, meteorological data (temperature, precipitation and evapotranspiration) were collected from meteorological stations near the study sites. Total phytomass was sorted into S. pumila and other species. We used a generalized linear mixed models (GLMM) and found the abundance of S. pumila to be inversely correlated with rainfall and the presence of other species, but positively correlated with temperature increase. The increase of S. pumila above‐ground phytomass production was linked to a reduction of forage quality.  相似文献   
59.
为探明毛果胡卢巴、劲直黄芪、天蓝苜蓿、镰荚棘豆和窄叶野豌豆5种野生豆科牧草种子萌发的适宜温度以提高其萌发率,研究了0/10℃ 、5/15℃ 、10/20℃ 、15/25℃ 、20/30℃ 、25/35℃ 、30/40℃等7种发芽温度对西藏5种野生豆科牧草种子萌发的影响.结果表明,5种野生豆科牧草种子在0/10℃条件下均无萌发;发芽率、发芽势、发芽指数和活力指数等指标随昼夜温度的升高呈先上升后下降趋势;毛果胡卢巴、劲直黄芪、天蓝苜蓿、镰荚棘豆和窄叶野豌豆牧草在适宜温度范围内种子萌发时滞最短,依次为2,2,2,3,4d;毛果胡卢巴和镰荚棘豆种子萌发最适温度为15/25℃,发芽率分别高达95%和812.5%;劲直黄芪、天蓝苜蓿、窄叶野豌豆种子萌发最适温度为20/30℃,发芽率依次为85%、912.5%和65%.  相似文献   
60.
为解决3 种豆科牧草愈伤组织继代培养中的褐化问题,以‘新牧4 号’紫花苜蓿、普通红豆草和‘海法’三叶草愈伤组织为材料,探讨不同防褐化措施在3 种豆科牧草愈伤继代培养过程中抗褐化效果的影响。结果表明,在苜蓿和红豆草愈伤组织的继代培养中,对愈伤组织褐化抑制效果较好的是AgNO3,浓度为0.02 g/L 时,褐化率分别为13%、15%,愈伤组织褐化程度强弱依次是PVP>柠檬酸>AgNO3;在三叶草愈伤组织的继代培养中,对愈伤组织褐化抑制效果较好的是AgNO3,浓度为0.015 g/L时,褐化率为32%,愈伤组织褐化程度强弱依次是柠檬酸>PVP>AgNO3。一定浓度的AgNO3不仅能有效控制褐化,还在一定程度上促进了愈伤组织的生长。  相似文献   
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