3种牧草不同搭配方式对胜红蓟的替代控制   总被引：1，自引：0，他引：1  

李光义  侯宪文  邹雨坤  刘振迪  李勤奋 《杂草科学》2013,31(2)

研究3种牧草不同搭配方式对胜红蓟的替代控制效果,为入侵杂草胜红蓟的防控提供植物种和替代控制方法.在田间条件下,通过将白三叶、杂交甜高粱、杂交狼尾草3种牧草两两等比例搭配后与胜红蓟按2∶1混种,建立3种不同的替代控制方式,动态监测各群落(种群)植物、土壤微生物指标,评价3种牧草两两等比例搭配对胜红蓟的替代控制效果.结果表明:白三叶、杂交甜高梁等比例搭配对胜红蓟进行替代控制时,2种牧草株高严重受阻,牧草相对盖度占优,Simpson指数和Shannon-wiener指数均变大,胜红蓟重要值变小,土壤真菌增多,细菌、放线菌减少;白三叶、杂交狼尾草等比例搭配对胜红蓟进行替代控制时,2种牧草株高不受阻,牧草相对盖度占优,Simpson指数变大,Shannon-wiener指数变小,胜红蓟重要值变小,土壤真菌增多,细菌、放线菌减少;杂交狼尾草和杂交甜高粱等比例搭配对胜红蓟进行替代控制时,杂交狼尾草株高不受阻,但杂交甜高梁株高严重受阻,牧草相对盖度占优,Simpson指数变小,Shannon-wiener指数变大,胜红蓟重要值变小,土壤细菌增多,真菌、放线菌减少.总体来看,白三叶和杂交狼尾草可以等比例搭配作为胜红蓟替代控制材料,且替代控制效果较好;白三叶和杂交甜高粱、杂交甜高粱和杂交狼尾草不宜等比例搭配作为胜红蓟的替代控制材料.  相似文献   

Influence of sward botanical composition on performance of cool temperate grassland under contrasting nitrogen fertilization regimes     

《Communications in Soil Science and Plant Analysis》2012,43(17-18):2855-2864

Kikuyugrass (Pennisetum clandestinum Hochst. ex Chiov.) is an active silicon (Si) accumulator, and Si can reduce the organic‐matter digestibility of forage grasses. Calcium carbonate (crushed coral) applications to a low Si Maile silt loam soil (Acrudoxic Hydrudands) had no effect on the in vitro digestible organic matter (IVDOM) concentration of 3‐week‐old (4.5‐leaf‐per‐tiller stage of development) ‘Whittet’ kikuyugrass regrowth, whereas calcium silicate (wollastonite) applied at the calcium equivalent of the calcium carbonate rates produced a curvilinear (crescent‐shaped quadratic) IVDOM response. Whittet IVDOM decreased when grass Si concentration exceeded about 22 g kg^?1 or when 0.5 M acetic acid–extractable soil Si exceeded about 230 mg kg^?1. Common and ‘Hosaka’ kikuyugrass regrowth on the Maile soil had less Si and greater IVDOM concentrations than those observed for high‐Si Kohala (Humic Dystrustepts) and Waialua (Pachic Haplustolls) silty clay soils. Whittet had greater crude protein and IVDOM concentrations and lesser fiber concentrations than common.  相似文献   

‘热研4号’王草和五节芒光合特性的比较   总被引：1，自引：0，他引：1  

高瑞芳  李春江  秦甜甜  张建国 《华南农业大学学报》2015,36(2):55-60

【目的】获得生产生物能源的优质原料.【方法】在田间采用LI-6400便携式光合作用测定仪对‘热研4号’王草Pennisetum purpureum×P.americanum cv.Reyan No.4和五节芒Miscanthus floridulus的光合特性日变化进行研究,并分析了其净光合速率(Pn)与主要影响因子的相关性.【结果和结论】‘热研4号’王草和五节芒的净光合速率日变化均呈"单峰型",无光合"午休"现象,且‘热研4号’王草日均Pn(25.45μmol·m-2·s-1)略高于五节芒(25.08μmol·m-2·s-1).2种草的蒸腾速率(Tr)、水分利用效率(WUE)、光能利用率(LUE)和气孔导度(Gs)与Pn一样,最大值均出现在13:00时左右,且‘热研4号’王草的Tr、LUE和Gs也都略高于五节芒,只有WUE略低于五节芒.气孔限制值(Ls)日变化呈正钟型,在11:00时左右达最高值(均为0.86μmol·m-2·s-1),早晚最低,而胞间CO2摩尔分数(xi)日变化趋势与之相反.此外,‘热研4号’王草和五节芒的Pn均与大气CO2摩尔分数(xa)呈显著负相关(P0.05),且分别与空气相对湿度(RH)和Gs呈显著正相关(P0.05).以上结果说明‘热研4号’王草的光合能力比五节芒强.  相似文献   

Growth responses of cereal crops to organic nitrogen in the field     

Miwa Okamoto  Toshihiro Watanabe  Noriharu Ae 《Soil Science and Plant Nutrition》2013,59(3):445-452

Eleven rice varieties differing in grain size were grown under controlled environmental conditions during the grain-filling period. The grain weight of upper grains in a panicle was examined at successive stages of growth during the grain-filling period. The effect of temperature on the rate and the duration of the period of grain-filling was determined using Khao Lo, a large-grain variety, and Bom Dia, a small-grain variety. Both the grain-filling rate and duration of the period of grain-filling differed among rice varieties and were positively and significantly correlated with the grain size. The duration of the grain-filling period from flowering to the time when almost maximum grain weight was attained ranged from 12 days at 32/24°C in Bom Dia to 36 days at 20/12°C in Khao Lo. The grain-filling rate was low in small-grain varieties, and generally increased with increasing grain size.

By lowering the temperature, the grain-filling rate decreased, the duration of the grain-filling period increased but the grain weight was almost constant.

Weight per grain was closely correlated with hull size. No relationship was found between weight per grain and nitrogen percentage of brown rice.  相似文献   

狼尾草典型生理生化特征对阿特拉津胁迫的响应   总被引：2，自引：2，他引：0  

马兵兵  姜昭  叶思源  刘晓雪  马昱亨  张颖 《农业环境科学学报》2015,34(11):2083-2088

通过盆栽试验考察狼尾草生长(生物量及根冠比)及典型生理指标(叶绿素、丙二醛及脯氨酸含量)对不同浓度阿特拉津污染胁迫的响应规律.结果显示,高浓度阿特拉津胁迫下狼尾草生物量(≥ 100 mg·kg^-1)、根冠比(≥ 200 mg·kg^-1)两类生长指标与对照处理相比达到显著性抑制水平.阿特拉津胁迫(≤ 200 mg·kg^-1)对狼尾草叶片中叶绿素含量的影响较小,各污染处理样品叶绿素含量与对照组的差异不显著;阿特拉津污染胁迫水平达到100 mg·kg^-1时,狼尾草叶片中脯氨酸含量达到最大值(39.38 μg·kg^-1),同时丙二醛含量与对照处理相比呈现显著升高的趋势.上述结果表明:只有在较高浓度阿特拉津(≥ 100 mg·kg^-1)胁迫水平条件下,狼尾草典型生长及生理指标才逐渐受到极显著影响,从植物生长与生理角度揭示了狼尾草对阿特拉津具有较强的耐受能力.  相似文献   

Evaluation of indices for identification of pearl millet cultivars adapted to stress and non-stress conditions     

O. P. Yadav  S. K. Bhatnagar 《Field Crops Research》2001,70(3):201-208

Pearl millet (Pennisetum glaucum) is cultivated across a wide range of environments ranging from extremely stressful to favourable. The objective of this research was to compare methods to identify productive cultivars for stress and non-stress conditions. Thirty pearl millet cultivars were evaluated at 22 locations that were grouped as stress, non-stress, or intermediate environments. Five selection indices viz., arithmetic mean (AM), geometric mean (GM), AM (standard units), stress susceptibility index (S) and drought response index (DRI) were calculated for each genotype to determine correlation between selection indices and yield under stress (Y_S), non-stress (Y_NS), and average conditions (Y_AV). Both cultivars and locations were significant sources of variation. Phenology of cultivars had different influence on yielding ability in contrasting environments. While earliness was advantageous for stress conditions, cultivars with longer duration tended to yield more under non-stress conditions. Y_S was only moderately determined by Y_NS. Both AM and GM were suitable indices for selection of cultivars that would perform well across stress, non-stress, and intermediate environments. Stress susceptibility index (S) was negatively correlated with Y_S (r=−0.62^**) but should only be used as a selection criterion in combination with yield under stress (Y_S) to identify cultivars adapted to stress environments. DRI was positively correlated with Y_S but had no association with Y_NS. Results indicated that DRI might be useful for identifying cultivars with high performance under stress particularly when days to flower differ considerably among test entries.  相似文献   

Response of Stipa bungeana and Pennisetum flaccidum to urine of sheep in steppe grassland of north‐western China     

Y. W. Yu  Z. B. Nan  F. J. Hou  C. Matthew 《Grass and Forage Science》2009,64(4):395-400

Urine [12·3 g nitrogen (N) L^?1], collected from native Tan sheep in rangeland of the Loess Plateau in north‐western China, was applied to vegetation patches dominated by Stipa bungeana (C₃ grass) or Pennisetum flaccidum, (C₄ grass) at either 0, 1·0, 2·0 or 4·0 L urine m^?2 in early‐, mid‐, or late‐growing season, and herbage mass and tiller number per sample recorded, allowing calculation of the respective contributions of increases in tiller weight and tiller density to the response from N in urine. Such records were made three times in the growing season of application of urine, and at the end of the following growing season. Responses to urine were of the order of 1 and 5 kg herbage DM kg^?1 N applied for S. bungeana and P. flaccidum, respectively. Except for early‐season application, responses of S. bungeana were mainly expressed in the season following urine application whereas responses of P. flaccidum tended to be expressed within the year of urine application, although with a residual response in the following year. The general pattern was for a tiller density‐mediated response in the period immediately after application, followed later by a tiller weight‐mediated response. Taken together with other recent research, S. bungeana can be considered a stress‐tolerating species with a limited response to N application and P. flaccidum an opportunist species able to capitalize on increased N supply.  相似文献   

Genetic diversity among pearl millet maintainers using microsatellite markers     

R. K. Kapila    R. S. Yadav    P. Plaha    K. N. Rai    O. P. Yadav    C. T. Hash    C. J. Howarth 《Plant Breeding》2008,127(1):33-37

Genetic diversity among 70 maintainers and two pollinators of sub-Saharan and Indian origin was studied for simple sequence repeat (SSR) loci using 34 primer pairs. A total of 213 alleles were detected with an average of 6.26 alleles per locus. Polymorphic information content (PIC) ranged from 0.05 to 0.96 with a mean of 0.58 for the SSR loci. Mean PIC across the linkage groups and number of alleles in dinucleotide motifs varied significantly. The lowest PIC (0.239) for linkage group 6 indicated comparatively conserved nature of this linkage group. Genetic similarity estimates ranged from 0.05 to 0.73 with an average value of 0.29. This indicated sufficient diversity among the maintainer and pollinator lines. The 72 lines fell in five clusters, and the clustering pattern corroborated with their pedigree and characteristic traits. Pollinator ICMR 356 was more diverse from the maintainer lines analysed, and can be a potential parent for pearl millet hybrid development.  相似文献   

SPAD值与杂交狼尾草施氮水平和农艺性状的关系   总被引：4，自引：2，他引：2  

黄勤楼  黄秀声  钟珍梅  陈恩  郑金贵 《热带作物学报》2008,29(2):159-163

采用盆栽试验探讨利用叶绿素计(Chlorophyll Meter SPAD-502)预测杂交狼尾草粗蛋白含量和牧草的施氮水平.试验设5个氮肥水平(纯氮量0,100,200,300,400k9/hm2)和3次重复,利用叶绿素计读取不同氮水平不同时期杂交狼尾草倒数第3片叶子的SPAD值,同时测定部分农艺性状和茎叶粗蛋白含量.结果表明,杂交狼尾草的SPAD值和粗蛋白含量是随着牧草的生长而逐渐降低,分蘖数、株高和生物产量随着牧草的生长而提高;杂交狼尾草的SPAD值与其施氮水平、分蘖数、株高、产量和茎叶粗蛋白含量都成正相关,与牧草的株高相关性最小且都不显著;与牧草的分蘖数和产量相关性大,接近或达显著水平:与牧草的茎叶粗蛋白含量相关性最大,均达显著或极显著水平.因此,利用SPAD值可用来预测杂交狼尾草茎叶粗蛋白含量,进而诊断杂交狼尾草的氮素营养水平,为牧草的合理施肥提供依据.  相似文献   

热研4号王草的适应性及其在福建的推广应用   总被引：1，自引：0，他引：1  

陈志彤  黄勤楼  潘伟彬  黄毅斌 《热带农业科学》2009,29(7):25-27

通过适应性研究,发现热研4号王草适合在福建地区生长。该草表现为产量高、生长快、营养品质高,适口性好等优点,表现出良好的生态适应性和经济价值,适宜福建地区在种草养畜、种草养鱼、养殖场污染治理、荒山生态恢复等方面推广应用。  相似文献