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排序方式: 共有55条查询结果,搜索用时 15 毫秒
1.
 以狗牙根和草地早熟禾为材料,用二因素二次正交旋转设计,对9个不同播种比例混播草坪的种群性状进行研究,建立了草坪地上生物量、地下生物量及一致性与狗牙根和草地早熟禾播种量之间显著相关的回归模型。确定了影响草坪性状的主要因子,优化了混播草坪的最佳播种量。  相似文献   
2.
对冻害胁迫下新农一号狗牙根、喀什狗牙根、矮生天堂草的抗寒能力研究结果表明经除雪,在乌鲁木齐-25.6℃下新农一号狗牙根、喀什狗牙根能安全越冬,矮生天堂草则不能越冬;细胞电解质渗透率能够很好的反映出品种间抗寒能力的差异,可作为衡量狗牙根耐寒能力的有效生理指标;SOD、POD酶活性及其持续时间的长短可能与狗牙根的抗寒能力有一定的正相关性;聚丙烯酰胺凝胶电泳发现,新农一号狗牙根的POD同工酶谱带数多于其他两个品种,且冻害适应中未有新的同工酶谱带出现;与茎、叶相比,根茎更能反映出品种间抗寒能力的差异程度且更耐寒.  相似文献   
3.
Background: The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle offered bermudagrass [Cynodon doctylon (L) Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 hay diets: low (L), medium low (ML), medium high (MH), and high (H) crude protein (CP) concentration (79, 111,131, and 164 g CP/kg on a DM basis, respectively). Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08:00 and 16:00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake (DMI), DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results: Forage DMI was affected by diet (P = 0.02), and DMI from MH and H was greater (P 〈 0.05) than from L. Apparent DMD tended (P = 0.08) to differ among diets while FO (P = 0.20) was not affected by diet treatments. Average ADL recovery (1.16) was greater (P 〈 0.05) than that of ADIA (1.03) and APL (1.06), but ADIA and APL did not differ (P = 0.42). Estimates of FO and DMD derived using APL and ADIA were not different (P≥0.05) from total fecal collection while those using ADL differed (P 〈 0.05). There was no diet by marker interaction (P≥ 0.22) for either FO or DMD. Conclusion: Acid-detergent insoluble ash and APL accurately predicted FO and DMD of cattle fed bermudagrass hay of varying nutrient composition. These internal markers may facilitate studies involving large numbers of animals and forages. Results from such studies may be used to develop improve  相似文献   
4.
狗牙根种质资源及遗传多样性的研究概况   总被引:7,自引:0,他引:7  
介绍了国内外狗牙根种质资源的研究概况;从形态学水平、染色体水平、蛋白质水平、DNA水平对狗牙根的遗传多样性进行概述,并对存在的问题提出建议。  相似文献   
5.
通过对盆栽狗牙根(新农一号狗牙根)、喀什狗牙根、C-3(狗牙根品系)、矮生天堂草以0、0.4%、0.8%、1.2%、1.6%五个土壤盐浓度进行处理,对其K+、Na+离子变化情况做了研究.结果表明相同盐浓度水平下,狗牙根体内K+、Na+离子含量茎叶大于根系,茎叶是K+、Na+离子累积的主要部位;K+/Na+比茎叶大于根系,说明茎叶耐钠性大于根系;随着盐度水平的递增,新农一号狗牙根、喀什狗牙根、C-3狗牙根K+、Na+离子吸收选择性系数增大,新农一号狗牙根>喀什狗牙根>C-3>矮生天堂草.由此初步认为,狗牙根抗盐性从大到小依次为新农一号狗牙根>喀什狗牙根>C-3狗牙根>矮生天堂草.  相似文献   
6.
新疆狗牙根农艺性状及利用价值初探   总被引:5,自引:0,他引:5  
对新疆具有代表性的7份狗牙根Cynodon dactylon材料的12项农艺性状进行初步研究表明,新疆狗牙根种内差异大,具有培育优良新型牧草或草坪品种的潜力,其中C5植株高大、茎秆粗壮、叶片大、草产量高,C1植株矮小、茎秆及叶片纤细、颜色深绿,其余材料居中;通过农艺性状聚类分析,结合加权综合评价结果,初步将新疆狗牙根划分为3个类型,即草坪草牧草兼用型(包括喀什狗牙根、新农一号狗牙根、C4、C3)、草坪型(C1、C2)、牧草型(C5),为今后新疆狗牙根种质资源的进一步开发利用提供科学的依据。  相似文献   
7.
赵琴  刘君  杨志民 《草地学报》2012,20(6):1156-1162
狗牙根(Cynodon dactylon)是全球最重要、品种最丰富的暖季型草坪草种之一,种或品种间形态相近,采用传统形态学和田间小区试验等方法难以作出鉴定,本试验利用AFLP分子标记技术,对9份常用狗牙根材料的遗传多样性进行了分析。结果表明:13对引物共扩增出1326个条带,平均每对引物扩增出93.2条带,其中多态性条带有1212条,多态性条带比率为91.71%,材料间遗传相似系数(GS)为0.469~0.797,变幅为0.328。聚类分析表明,在GS值为0.648处,可将9份常用狗牙根材料分为5类:T-419、小矮人和老鹰草为一类,摄政王单独为一类,瑞拉和黑杰克为一类,南京狗牙根和普通狗牙根聚为一类,阳江狗牙根单独为一类。依据P7/M3引物对电泳图谱,构建了9份狗牙根材料的指纹图谱。  相似文献   
8.
Coconut palm ( Cocos nucifera ), oil palm ( Elaeis guineensis ), Bermudagrass ( Cynodon dactylon ) and Madagascar periwinkle ( Catharanthus roseus ) with symptoms indicative of phytoplasma disease were collected from different locations in Malaysia. PCR assays employing phytoplasma universal rRNA gene primers P1/P7 alone or P1/P7 followed by R16F2n/R16R2 detected phytoplasmas in eight out of 20 Malayan Red Dwarf (MRD), nine out of 12 Malayan Yellow Dwarf (MYD) and 12 out of 12 Malayan Tall (MT) coconut palms displaying coconut yellow decline symptoms. Positive detections were also obtained from six out of six oil palm seedlings showing symptoms of yellowing and necrosis, from 10 out of 10 Bermudagrass samples with white leaf symptoms, and from eight out of eight periwinkle plants showing phyllody, virescence, little leaf, proliferation and foliar yellowing. Phytoplasmas were not detected in any of the symptomless plants tested. Sequencing and phylogenetic analysis of PCR products determined that phytoplasmas infecting both MRD and MT coconuts and Bermudagrass in Serdang, Selangor State, were all members of the 16SrXIV ' Candidatus Phytoplasma cynodontis' group, whereas isolates in periwinkle in Serdang were all members of the 16SrI ' Ca. Phytoplasma asteris' group. However, the phytoplasmas detected in MYD coconuts and oil palms from Banting, Selangor State, and in periwinkle from Putrajaya were collectively very similar (99%), but shared <97·5% similarity with 16S rDNA sequences of all other known phytoplasmas, indicating that they represent a novel taxonomic group. Thus, at least two phylogenetically distinct phytoplasmas are associated with the coconut yellow decline syndrome in Malaysia, both of which were also detected in other plant species.  相似文献   
9.
硅肥对盐胁迫下狗牙根生理生化特征的影响   总被引:2,自引:0,他引:2  
以狗牙根品种运动百慕大、天堂419和天堂328为材料,分析硅肥对不同盐浓度(在去离子水中将NaCl和CaCl2配比成0、3.35g/L、6.70g/L和11.25g/L共4个不同的盐浓度)胁迫下狗牙根草坪草叶中叶绿素、相对含水量、脯氨酸含量、电解质渗出率及根干重和根中Na+和K+含量的影响,以期为狗牙根草坪建植时的施肥管理及盐水灌溉时的品种选择提供理论依据。结果表明:随着盐浓度增加,3种狗牙根叶中叶绿素、相对含水量以及根干重、根中K+含量均下降;而叶中脯氨酸、电解质渗出率及根中Na+含量则呈增加趋势;硅肥的施用可以降低3种狗牙根草坪草叶中脯氨酸、电解质渗出率和根中Na+含量,同时增加叶中叶绿素、相对含水量及根干重、根中K+含量;综合各生理生化指标,运动百慕大狗牙根草坪草在施用硅肥后对盐胁迫的适应能力更强。  相似文献   
10.
The development of cultivars ‘TifGrand’ and ‘Celebration’ has shown potential increases in shade tolerance compared to previous industry standards of bermudagrass (Cynodon spp.). Based on the literature, further improvements in shade tolerance can be attained through changes in nitrogen fertility rates, mowing heights, and the application of plant growth regulators. In this study, two South African hybrid (Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy) bermudagrass accessions (‘WIN10F’ and ‘STIL03’) and three standard cultivars (Celebration, Tifgrand, and ‘Tifway’) were compared for their ability to persist under 63% shade, two mowing heights, two trinexapac-ethyl (TE) treatments, and two nitrogen fertility rates. The experimental design was a strip-strip-split plot and digital image analysis was used to measure percent turfgrass cover, percent turfgrass spread after cup-cutter removal, and percent turfgrass re-growth after divot formation. Turf quality was measured using the normalized difference vegetation index (NDVI). Differences among genotypes, TE treatments, and mowing heights were observed across all response variables in 2014 and 2015. Differences in fertility treatments were observed in NDVI, percent turfgrass growth, and percent turfgrass recovery within and across years. Significant differences were observed for the interactions between entry by plant growth regulator (PGR) treatments, entry by mowing height, and mowing height by PGR. These results suggest shade management recommendations should be dependent on genotype and site-specific considerations. The development and implementation of specific management plans for certain bermudagrass varieties will contribute to the more widespread use of Cynodon spp. in shaded environments.  相似文献   
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