苜蓿,红豆草地中秋季杂草种类及侵入量的调查     

王彦荣 《草业科学》1991,8(1):51-54

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紫花苜蓿自然株高变量分析   总被引：5，自引：0，他引：5  

白玉龙  姜永  巴雅尔  乌艳虹  陶红梅  韩晓华 《草业科学》2002,19(6):32-34

测定了9个紫花苜蓿品种生长高峰期的自然株高，统计分析结果表明，紫花苜蓿6－9周龄生长高峰期，各品种平均自然株高与株龄间呈非常显著（P＜0．01）或显著正相关，线性回归方程估测相对误差除Ranger大于5％外，其余线性回归方程估测相对误差均小于5％。第9周龄的Travois和皇后苜蓿平均自然株高显著不显著。第9周龄的Travois和皇后苜蓿平均自然株高显著（P＜0．05）高于对照品种敖汉苜蓿平衡自然株高，其余各参试品种与对照品种敖汉苜蓿比较，平均自然株高株不显著。第9周龄平均自然株高排序前4位的品种依次为Travois, 皇后苜蓿，Ranger,Baker。  相似文献   

黄土高原地形对苜蓿种子产量和质量的影响   总被引：17，自引：6，他引：11  

余玲  王彦荣  毛玉林  侯扶江 《草业学报》2002,11(4):62-67

对产自甘肃环县黄土高原沟壑区阴坡，阳坡、沟谷阶地和塬地4种地形的苜蓿种子产量和质量进行了研究分析，结果表明，地形对种子产量和质量均有显著影响，其中，阴坡种子产量最低，分别为1．86g/株和311．74kg/hm^2，阳坡单株种子产量最高，为6．41g/株，塬地单位种子产量最高，为650．65kg/hm^2，质量最低种子也产自阴坡，其发芽率只有23％，硬实率却高达66％，地形对种子产量构成因素无显著影响，4种地形的种子产量与其构成因素的相关性完全一致，即除千粒重外，种子产量与其他各因素均存在显著正相关，相关性强弱依次为：单株生殖枝数＞每生殖枝荚果数＞每荚粒数＞千粒重，单株生殖枝数对种子产量贡献最大。  相似文献   

甘肃张家川阴湿地区紫花苜蓿品比试验研究   总被引：1，自引：0，他引：1  

马彩琴  麻小风  丁喜琳  杨保春 《草原与草坪》2006,(3):69-71

通过对12个紫花苜蓿品种的产量、生长速度、越冬性、鲜干比、抗病虫害等方面的比较试验,结果表明阿尔冈金鲜草产量最高达41.57 t/hm2,其次为THG-1,兼用型FD3,天水苜蓿鲜草产量最低,仅为30.37 t/hm2;生长速度,越冬率,鲜干比等指标,筛选出的品种表现较好,且与对照天水苜蓿差异显著(P<0.05),因此,适宜于在当地种植的紫花苜蓿品种依次为THG-1,兼用型FD3,阿尔冈金,金皇后,多叶。  相似文献   

Selection for increased forage yield in alfalfa at different NaCl levels     

D. W. Johnson  S. E. Smith  A. K. Dobrenz 《Euphytica》1992,60(1):27-35

Summary Alfalfa (Medicago sativa L.) forage yield may be reduced by moderate levels of salinity. Increasing forage yield in saline environments through plant breeding could partially ameliorate this problem. However, prior indirect selection either in cell culture, at germination, or during seedling growth has not resulted in agronomically relevant levels of salt tolerance. This study was conducted to determine whether mean forage yield of alfalfa grown in saline environments could be increased. To reduce the number of possible selection schemes, forage yield data for five harvests from Sonora and its parental cultivar African grown in a greenhouse and irrigated with 0, 30, 60, or 80 mM NaCl were used to simulate one cycle of selection at each NaCl environment. Greatest gains in forage yield were expected under non-saline conditions with decreased gains under saline conditions. Selection based on yield in regrowth harvests was also predicted to be more efficient than that based on seedling harvest. Experimental populations were developed from Sonora and African at each NaCl level using phenotypic selection for increased mean forage yield for harvests 3 to 5. After each of two cycles of selection, forage yield from selected, control (plants selected randomly under non-saline conditions), and parental populations was evaluated at 0, 30, 60, and 80 mM NaCl. Gains in forage yield were observed in African when the selection and evaluation environments were the same, but in Sonora this was observed only at 0 NaCl. Selection at 0 NaCl did not increase forage yield at 60 or 80 mM NaCl in either germplasm source. This suggests that selection for increased forage yield may be successful at low to moderate NaCl levels in germplasm with ample variation for yield when grown in saline environments, while selection for increased forage yield in non-saline conditions may be ineffective.  相似文献   

High frequency somatic embryogenesis with a pampeana-derived genotype of alfalfa (Medicago sativa L.)     

María Valeria Romagnoli  Juan Pablo A. Ortiz  Gerardo D. Cervigni  Cintia Heisterborg  Rubén H. Vallejos 《Euphytica》1996,90(1):89-93

Summary Somatic embryos of genotype R11 of the alfalfa variety Pampeana were produced from embryogenic calli derived from leaf sections. They were induced by an auxin shock and its development was attempted on six different media. The best condition for somatic embryo production was inducing callus on MS medium plus 10 M 2,4-D and 4,6 M KIN and transferring them, after the auxin shock, to MS with 10–20 mM NH₄ ⁺ and 30 mM proline. More than 500 somatic embryos per plate were produced. Embryos were grown to plants on MS or half strength MS media and all regenerated plants resembled the original R11 genotype. This technique could be useful in alfalfa Pampeana improvement using genetic modification.  相似文献   

Breeding alfalfa cultivars resistant to the alfalfa weevil     

T. H. Busbice  W. V. Campbell  L. V. Bunch  R. Y. Gurgis 《Euphytica》1978,27(2):343-352

A ten-year study consisting of nine field experiments was conducted to evaluate alfalfa (Medicago sativa L.) for resistance to larval feeding by the alfalfa weevil (Hypera postica Gyllenhal). The results were consistent over years and experiments. Only one source of alfalfa germplasm, designated Starnes, showed resistance to larval feeding in the field under natural infestations of the weevil. The cultivars Team, Arc, and Liberty have been developed from this germplasm source. The only effective method of selection for field resistance to the weevil was field selection under natural weevil infestations. Selection was based on low larval feeding on spaced plants. After six generations of such selection the Starnes germplasm showed only one-third as much defoliation as did the check cultivars. The heritability of the weevil resistance was moderately high. Field resistance was transferred to other strains through hybridization; hybrids were intermediate to the resistant and susceptible parents. Resistance was stable.Laboratory and greenhouse efforts to breed alfalfa weevil resistant alfalfa-using such techniques as adult cotyledon-nonpreference tests, adult leaf-feeding tests, larval-growth and survival tests, oviposition-stimulus tests, and oviposition-nonpreference tests-have failed to produce field resistance.Paper No. 5308 of the Journal series of North Carolina Agricultural Experiment Station, Raleigh, N. C., in cooperation wich ARS, USDA. Received 15 June 1977.  相似文献   

黄土高原沟壑区人工草地生产力研究—以长武王东沟试验区苜蓿地为例   总被引：4，自引：0，他引：4       下载免费PDF全文

聂庆华  宋桂琴 《水土保持通报》1993,13(5):22-27

该以长武王东试区苜蓿为例，根据草地生产力形成机制，结合一系列试验数据，探讨了人工草地生产潜力及其载畜量的估算方法。析人工草地生产力形成过程，量化了各种生态因子的产量效应，指明了提高草地生产力及其载畜量的有效途径。  相似文献   

苜蓿细胞悬浮培养与耐受高浓度PEG变异体的筛选   总被引：10，自引：0，他引：10  

张晓东  林廷安 《核农学报》1994,8(1):0-0

本文对紫花苜蓿的细胞悬浮培养、悬浮细胞系的建立、离体辐射效应和高浓度ＰＥＧ耐受性变异体的筛透进行了研究。结果表明：１．高浓度的２，４．Ｄ（５～１０ｍｇ／Ｌ），低浓度的ＡＢＡ（０．１～２ｍｇ／Ｌ），高浓度的蔗糖（６％～９％），较高的离子强度，以及逐步缩短继代时间，均有利于胚性悬浮细胞系的快速建立。相反，细胞分裂素，高浓度的ＮＨ和ＧＡａ的存在，不利于悬浮系的建立。细胞分裂素（４ＰＵ３０，ＫＴ或ＢＡ）可促进细胞的团聚，不利于细胞的分散。此外，低浓度的２，４－Ｄ，４ＰＵ３０（或ＢＡ，ＫＴ）和ＡＢＡ的配合使用，在悬浮培养基中可形成大量的体细胞胚。２．辐射处理悬浮细胞的最适剂量为２０～６０Ｇｙ。３．未经改造的初期悬浮培养物远较悬浮细胞系对高水势敏感。４．胚性悬浮细胞系经２０Ｇｙ的γ射线处理，筛选出了对１５％ＰＥＧ水势（约－１１巴）耐受性的克隆６个，并获得了一批再生植株，从２０％ＰＥＧ（约－１５巴）筛选出１个抗性克隆。抗性细胞系对高浓度ＰＥＧ和ＮａＣｌ产生的水势在细胞水平表现出很强的抗性。  相似文献   

黄土高原地区苜蓿生产力动态及其土壤水分消耗规律   总被引：3，自引：1，他引：3  

万素梅  胡守林  贾志宽  曹永红 《农业工程学报》2007,23(12):30-34

为了解不同生长年限苜蓿生产力及土壤水分的变化特征，该文系统研究了黄土高原地区3年、4年、6年、8年、12年、18年及26年生紫花苜蓿生产力动态及土壤水分的消耗规律。结果表明：不同生长年限苜蓿鲜草产量存在极显著差异。苜蓿草地土壤水分呈现规律性的变化：随土层深度的增加，土壤含水率增加，300cm土层以下，土壤含水率变化趋势平缓。苜蓿生长超过18年，上层土壤水分开始恢复，但深层土壤通体干化，水分难以恢复。苜蓿水分利用效率随生长年限的延长而降低。研究表明在黄土高原半湿润区紫花苜蓿适宜的生长年限为8年，第6年为苜蓿的生长高峰期。  相似文献