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60Co-γ射线辐照处理对决明若干生长特性的影响 总被引：3，自引：0，他引：3
利用^60℃o-γ射线（辐照剂量为300 Gy,剂量率为4.687 5 Gy/min）辐照豆科决明属5个牧草品种的种子,通过盆栽收集各个品种的M1代种子,然后进行M2代试验与观察.结果表明,辐照后5个决明M2代的种子出苗率、植株的茎长、叶宽均无显著差异;34721号决明植株冠高有显著增长、2219号决明茎径有显著增长、86134号决明分枝数有极显著增长,92985号决明分枝数则有显著降低、86134号决明叶数和地上部植株干重有显著增长、2219号决明叶长增长显著,其余参试品种则无显著差异.植株的营养成分测定表明：仅2219号决明K含量呈显著下降、其他品种的N,P,K含量则无显著差异;2219不仅氨基酸总量呈显著下降、而且17种氨基酸都表现为不同程度的下降,86134氨基酸总量有显著增长、同时17种氨基酸都表现为不同程度的增长,而其余3个参试品种都无显著差异.经^60Co-γ射线辐照处理后的34721,86134,92985的酯酶同工酶谱与相应的对照有明显差别.生长观察结果表明,参试的5个决明品种M2代植株生长的现蕾期、初花期、盛花期、初荚期、盛荚期、成熟期表现为双向性,既有提早,也有推迟. 相似文献
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通过有性杂交和辐射处理5个决明属牧草品种进行新品种选育研究。结果表明：圆叶决明种内杂交取得成功;圆叶决明和羽叶决明种间杂交,以圆叶决明为母本的杂交组合已有结荚后代;有性杂交筛选到6株农艺性状已基本稳定的生物量大、分枝多的杂交株系后代。辐射育种筛选到5个品质优良的新品系,其中2个86134品种辐射变异后．后代品系的茎长和生物量有明显提高,茎叶比则呈明显下降;2个92985品种辐射变异后,后代品系的粗蛋白含量有明显提高;1个34721品种辐射后,后代品系的Ca含量有明显提高。 相似文献
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豆科牧草绿肥圆叶决明、羽叶决明在闽东的再生性研究 总被引：4，自引：0，他引：4
通过对9个圆叶决明、羽叶决明品种(系)的再生性能进行观测，及对5个圆叶决明、羽叶决明品种(系)进行收割试验得出：9个品种(系)的再生植株处理的长势、产量和种子产量均好于种子自然落地萌发植株的处理：92985、34721品种(系)表现出较强的综合再生能力和耐割(牧)能力；刈割植株时，留茬高度应控制在20cm以上。 相似文献
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决明（Cassia tora L.）为豆科决明属半常绿灌木，老枝灰褐色，幼枝呈绿色。秋季开鲜黄色花，花期8—12月，在园林植被中尤为夺目。本课题自2003年引进在温州植物园试种，表现出良好的适应性，观赏性也较好，是温州城市园林绿化中值得推广应用的花灌木新种。 相似文献
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决明属（Chamaecrista spp）豆科牧草8个品种化感潜力的研究 总被引：1，自引：0，他引：1
研究决明属（Chamaecrista spp.）豆科牧草8个品种[圆叶决明（Chamaecrista rotundifolia）CPI86134、CPI34721、CPI86178、CPI3248、ATF2232、CPI57503和羽叶决明（Chamaecrasta nictitans）ATF2217、ATF2219]对禾本科牧草百喜草（Paspalum notatum）的化感作用,以确定该8个豆科牧草品种的化感潜力。结果表明,8个决明属豆科牧草品种具有较强的化感作用;随着浓度的逐渐降低,8个品种开花期浸提液的化感抑制作用逐渐减弱,结荚期浸提液的化感促进作用逐渐加强;同一品种,同一生长时期,不同浓度（5%、7.5%和10%）的化感作用综合效应表现不同;同一生长时期,同一浓度,不同品种的化感综合效应表现也不同。可见,决明属牧草8个品种的化感作用受浓度、生长时期和品种的影响。 相似文献
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几个决明属牧草在亚热带丘陵红壤的个体与群体生长特性 总被引：8，自引：0，他引：8
从引进的40个决明属牧草品系中选出代表性品系观测其生长表现,结果表明决明品种均表现为出苗率低、出苗时间长、种子成熟度低,营养含量差异较小。个体与群体生长研究结果表明,ATF2228品系为匍匐型、早熟品种,生物量低;ATF2217和ATF2219为直立型、中早熟品种,种子产量高、生物量大、再生能力较差,适于1年1次刈割利用;CPI92985的品种特性与CPI34721相类似,都是半匍匐型、中早熟品种,但CPI92985的生物量、种子产量、茎叶营养含量及刈割后再生能力好于CPI34721;CPI86134和CPI86172为半匍匐型、迟熟品种,冠高和生物量均大于CPI92985和CPI34721。另外,施肥可以显著提高CPI86134的生物产量和刈后再生能力,达到1年3～4次刈割利用,值得进一步研究。 相似文献
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稻属植物叶背亚显微结构的观察研究 总被引：17，自引：0，他引：17
用扫描电镜对稻属植物9个种叶背的大瘤状乳突、本栓细胞乳突和气孔器乳突的亚显微结构作了比较观察研究。依有无木栓细胞乳突、有无气孔器乳突和有无大瘤状乳突而将其分为四群。群间有质的不同，群内亚种间和品种间只有数量之别。表明用亚显微形态结构作为分类性状是有意义的。 相似文献
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研究了羽叶决明(Chamaecrasta nictitans)替代麸皮栽培鸡腿菇(Coprinus comatus)对其产量、绝对生物学效率、基物失重、呼吸消耗及木质纤维素转化的影响。结果表明,羽叶决明牧草替代20 %麸皮(B2)栽培鸡腿菇的产量和绝对生物学效率最高,分别为235.2 g/袋和8.86 %。覆土前和采收后的基物失重、呼吸消耗都以B6为最高,分别为13.50 %、13.50 %和35.03 %、30.71 %,其纤维素转化率也最高,为33.61 %;木质素转化率以B1为最高,达78.25 %;半纤维素转化率以B2为最高,为44.10 %。回归分析表明,羽叶决明替代麸皮栽培鸡腿菇的产量、绝对生物学效率和半纤维素转化率与替代比例呈抛物线相关,而基物失重、呼吸消耗及木质素、纤维素转化率与替代比例呈线性相关。 相似文献
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北方地区近些年积极推广林草间作模式,较传统的林地裸露方式,其经济效益、生态效益更加明显.结合北方地区的实际,从林草间作模式下树种及草种的选择、林草间作的类型、树木栽植、牧草播种、间作后的管理等多个方面对林草间作技术的要点进行简单的总结,以促进该技术在北方地区的大面积推广. 相似文献
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Scott B. Maresh Nelson Jaime J. Coon Walter H. Schacht James R. Miller 《Grass and Forage Science》2019,74(3):486-495
Tall fescue (Festuca arundinacea) is a Eurasian forage grass extensively planted in the United States. However, an endophytic fungus in tall fescue, Epichloë coenophiala, causes health problems in cattle. We predicted that cattle prefer to graze alternative forages when available. We also predicted that cattle use tall fescue more intensively in recently burned areas, as fire can increase forage quality. We tested these predictions in four diverse‐forage pastures in Iowa, comparing use by cattle of tall fescue and four alternative forages (non‐fescue cool‐season grasses, native warm‐season grasses, non‐leguminous forbs and legumes) to their availabilities at the pasture scale. We also examined how tall fescue influences the distribution of grazing at a fine scale (0.1‐m2 quadrats). Tall fescue was the most abundant forage (46% of plants), but composed only 26% of grazed vegetation. In contrast, legumes composed 12% of available forage but 25% of grazed vegetation. Other forages were used in proportion to availability. At a fine scale, total grazing frequency (proportion of plants grazed) was lower in quadrats containing abundant tall fescue, and higher in quadrats with abundant warm‐season grasses. Grazing frequency of tall fescue and other cool‐season grasses was greatest in recently burned quadrats, but total grazing frequency did not increase after burning. Our results show that although cattle graze tall fescue, particularly following burns, they limit their use of this grass. Given that tall fescue is underused, creates health risks for cattle, and degrades wildlife habitat quality, it may be advisable to reduce tall fescue in pastures. 相似文献
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Grazing lands in warm‐temperate and subtropical North America have become less diverse. Pastures are typically grass monocultures, while rangelands are generally managed for the grass components. Overstocking, selective herbicides, fire exclusion and heavy rates of nitrogen fertilizer have contributed to near exclusion of native, warm‐season legumes. The simplicity of managing grass monocultures, pasture production responses to nitrogen fertilizer and profitability of grass‐only systems have limited interest in legume‐based approaches. Changing economics and ecological concerns with ecosystem accumulation of industrial inputs contribute to an increasing interest in legumes. Unlike the development of temperate pasture legumes and recent research in the tropics, legumes tolerant of both freezing temperatures and hot weather have received less attention. Poor establishment, limited persistence and potential invasiveness limit currently available introduced species. Native, herbaceous, warm‐season legume species occur throughout warm‐temperate North America, but little attention has been directed to these plants as potential forage species. Some success with a few native legume species, primarily in the genus Desmanthus, suggests potential for expanded assessment of forage value of the many species available. Current assessments of native legumes, primarily for conservation purposes, provide an opportunity to expand evaluations of these species for pasture and rangeland potential while economics of livestock production and public interest in ecosystem health are supportive. Experiences with legumes of warm‐temperate origin in North America, along with results with temperate and tropical pasture legumes globally, provide a starting point for future efforts at incorporating greater legume diversity in pastures and rangelands of subtropical and warm‐temperate regions around the world. 相似文献
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A. H. Marshall M. T. Abberton T. A. Williams T. P. T. Michaelson-Yeates H. G. Powell 《Grass and Forage Science》2003,58(3):295-301
Interspecific hybridization with the close relative Trifolium nigrescens Viv. (Ball clover) is a possible strategy to increase the seed yield potential of white clover (T. repens L.). Fertile F1 plants have been used as the basis for several generations of backcrossing using T. repens as the recurrent parent. Forage quality of the parental species and backcross hybrids when grown in mixtures with perennial ryegrass (Lolium perenne L.) was compared in field plots over three harvest years. The dry‐matter digestibility (DMD) and crude protein (CP) concentration of the legume fraction was greater than that of perennial ryegrass, but the water‐soluble carbohydrate (WSC) concentration of the legume components was lower than that of perennial ryegrass. Differences in forage quality between T. repens and the backcross hybrids were relatively small. The WSC concentration of the backcrosses was less than T. repens but the CP concentration was greater. Significant differences in the forage quality of the companion grass were observed when grown with the parental species and the hybrids; however, these differences were attributed to the plots with T. nigrescens and the F1 plants, where the clover content was low. Few differences in the forage quality of the grass were measured when grown with T. repens and the backcross hybrids. The impact of these results on the use of these hybrids in cultivar development programmes is discussed. 相似文献
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D. F. Osbourn 《Grass and Forage Science》1969,24(1):76-80
The origin and introduction of Pangola grass Digitaria decumbens (Stent) into the Caribbean islands is described. The rapid spread of this species in cultivation throughout the regions is ascribed to four characteristics which coincided so closely with the economic and technical needs of the region as to override the inherent disadvantages of this grass. Its outstanding characteristics are ease of establishment, vigour, adaptability, palatability and resistance to grazing. The agronomic and nutritional characteristics and the productive potential of Pangola grass are com-pared with other forage species cultivated in the region and with a temperate grass species. These characteristics are discussed in the context of the introduction and evaluation of forage species and the intensification of output from forage crops. 相似文献
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Ge Zhang Ashley L St. Clair Adam G Dolezal Amy L Toth Matthew E O&#x;Neal 《Journal of insect science (Online)》2021,21(1)
Prairie was a dominant habitat within large portions of North America before European settlement. Conversion of prairies to farmland resulted in the loss of a large proportion of native floral resources, contributing to the decline of native pollinator populations. Efforts to reconstruct prairie could provide honey bees (Apis mellifera) a source of much-needed forage, especially in regions dominated by crop production. To what extent honey bees, which were introduced to North America by European settlers, use plants native to prairies is unclear. We placed colonies with pollen traps within reconstructed prairies in central Iowa to determine which and how much pollen is collected from prairie plants. Honey bee colonies collected more pollen from nonnative than native plants during June and July. During August and September, honey bee colonies collected more pollen from plants native to prairies. Our results suggest that honey bees’ use of native prairie plants may depend upon the seasonality of both native and nonnative plants present in the landscape. This finding may be useful for addressing the nutritional health of honey bees, as colonies in this region frequently suffer from a dearth of forage contributing to colony declines during August and September when crops and weedy plants cease blooming. These results suggest that prairie can be a significant source of forage for honey bees in the later part of the growing season in the Midwestern United States; we discuss this insight in the context of honey bee health and biodiversity conservation. 相似文献
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M. G. Moraes N. J. Chatterton P. A. Harrison T. S. Filgueiras R. C. L. Figueiredo‐Ribeiro 《Grass and Forage Science》2013,68(1):165-177
Non‐structural carbohydrates (NSC) are the primary energy available for growth and dry‐mass production in forage grasses. They are also associated with tolerance to environmental stresses, including drought. Soluble carbohydrates, especially fructans of temperate forage grasses, have been extensively studied; however, little is known about NSC of tropical grasses. These plants are abundant in the Cerrado, a savanna‐like vegetation with a definite seasonality in rainfall distribution. Such an environment presents an ideal condition for the occurrence of fructans. However, the present analysis of carbohydrates in aerial parts of twenty‐four tropical grass species, mainly from the Panicoideae subfamily in the Cerrado, shows a distinctively different NSC profile when compared with temperate grasses. Free glucose and starch are common NSC found in most plant organs. However, free fructose and sucrose‐based oligosaccharides were only found in very low amounts. Sucrose was detected in higher amounts only in stems. A linear series of malto‐oligosaccharides was found in leaf blades, sheaths and stems of most of the Cerrado grasses, except for those from the Andropogoneae tribe. These results indicate a diversity of regulatory pathways of NSC metabolism in tropical forage grasses from the Cerrado. 相似文献
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Sulphur supply affects morphology,growth and nutritional status of Tanzania Guinea grass and Mineirão stylo 
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下载免费PDF全文 Forage plants constitute the primary food source for ruminants, and their aboveground growth and belowground growth depend on mineral nutrient supply. The objective of this study was to identify and quantify variation in morphology, production and nutritional status in Panicum maximum cv. Tanzânia and Stylosanthes guianensis cv. Mineirão grown with varying levels of S availability. In an experimental setting, plants of both species received rates of S calculated to reflect suboptimum, adequate and excessive levels of the element. S had a direct effect on morphology and production in both species. S limitation altered the allocation of photosynthates between the aboveground and belowground portions of Guinea grass and stylo, and was associated with lower root dry mass production. Guinea grass plants increased root surface area as an adaptive mechanism when S was limiting in the growth medium. The relative chlorophyll index of recently expanded leaves was correlated with aboveground dry mass production. After the initial growth, Guinea grass and stylo plants showed similar S requirements and use efficiency to achieve the maximum of aboveground productivity, although leguminous plants have a substantially higher capacity for store S in the shoot tissue as compared to gramineous plants growing under similar availability of S in the medium. While applying S was necessary for increasing dry mass production in both species, planting these species together is a promising strategy for guaranteeing high yields of forage with a nutritional value that satisfies the S requirements of ruminants. 相似文献