苏州城区古树名木的树势评价   总被引：1，自引：0，他引：1  

刘嘉  杨莉雷  陆小平 《安徽农业科学》2010,38(36)

为更好地保护和利用苏州的古树名木资源,应用层次分析法拟定古树树势量化指标,对苏州城区一级古树名木进行树势评价,阐述苏州古树名木保护现状,结合实例分析其中主要存在的问题以及产生这些问题的原因。  相似文献   

几种植物生长调节剂对决明种子萌发及幼苗生长的影响   总被引：3，自引：0，他引：3  

朱霞  胡勇  王晓丽  陈诗 《作物杂志》2010,(1)

分别采用GA3、6-BA和NAA处理决明(Cassia obtusifolia L.)种子,结果表明:GA3、6-BA、NAA可提高种子发芽率、发芽势和活力指数,还可增加幼苗的根数、全株鲜重和干重,三种植物生长调节剂都能够调节决明幼苗的生长发育,其中100mg/L对决明种子发芽和幼苗生长的作用效果最好。  相似文献   

关于提高棉花种子活力的研究     

潘恒晋  江厚旺  吴社兰  阚家瑜  张俊业  吴宁  夏静 《安徽农业大学学报》1992,(1)

本试验选用一定浓度的肥育型与化调型物质,对棉籽进行播前浸种,研究其对提高种子活力和棉苗素质的影响。结果表明:以1000ppmCO(NH_2)_2、1000ppm KH_2PO_4、300ppm“802”、200ppm CCC四种物质处理棉籽后,对提高种用品质,增强种子活力,产生了较好的生物效应。生产中可示范推广应用。  相似文献   

玉米种子活力测定方法的研究     

王景升  王振泰 《沈阳农业大学学报》1989,20(2):108-115

为了更好的预测玉米种子在春季田间条件下的出苗表现,我们以田间出苗率与实验室测定结果之间的相关分析为手段,对9种活力测定方法进行了筛选。低温测定结果与田间出苗率之间的相关较高,是其中最好的方法。通过采用砂床代替玉米田间土壤,改善了低温测定结果的重演性。联合试验和适合性鉴定的结果指出,低温测定的结果可以重演,并可适用于不同自交系与杂交种的种子。4年研究的的结果证明,低温测定发芽率与实际田间出苗率之间的(?)关是显著的,稳定地高于标准发芽率与出苗率的相关。  相似文献   

不同贮藏条件和方式对小麦种子活力的影响     

高灿伦  高荣岐 《山东农业大学学报(自然科学版)》1990,21(4):67-72

  相似文献   

Effects of the Polish Rootstocks P2 and P22 on Vigour,Yield and Fruit Characteristics of the Apple Cultivar ‘Gravenstein’     

Jonas Ystaas  Oddmund Fr⊘ynes 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):244-246

Abstract

The performance of the Polish rootstocks P2 and P22 under Norwegian growing conditions was evaluated over 10 years (1983–92). Tree vigour of the apple cultivar ‘Gravenstein’ on P2 and P22 was 64 and 16% of that on M9, respectively. Trees on P2 had the highest yield efficiency, but less total yield per tree than M9. Owing to very dwarfing growth, trees on P22 failed to establish a sufficient canopy and produced significantly smaller apples. P2 and P22 affected apple soluble solids in a favourable way, but did not influence fruit acidity.  相似文献   

水稻中413的广亲恢性及其系列组合   总被引：8，自引：2，他引：8  

罗利军  应存山 《中国水稻科学》1994,8(4):193-199

 中413是从50465中经系统选育而成的广亲和恢复系。与籼型测验种IR36，南京11测交，F₁结实率分别为75.5%和80.0%；与粳型测验种秋光，Balilla测交，结实率分别为71.4%和53.2%。对野败，矮败，Dissi，马尾粘等胞质不育系均具有较强的恢复能力。以中413为广亲恢系而配制的系列组合均有较强的杂种优势，在不同地区，不同季节种植均比对照汕优63和汕优10号增产或极显著增产。作单季种植，亩产可达700 kg以上；作双晚栽培，亩产可达600 kg左右。表现为秧苗素质号，生长势旺，耐肥抗倒，穗大，叶面积系数大，物质生产力高，穗多，库源关系协调。中413系列组合不仅表现较强的杂种优势，而且较好地克服了籼粳亚种间优势利用种F1结实率偏低，籽粒不饱满，植株偏高和生育期偏长等障碍。  相似文献   

Divergent recurrent selection for seedling tiller number in Altai wildrye     

P. G. Jefferson  T. Lawrence  & G. A. Kielly 《Grass and Forage Science》2001,56(3):285-293

Seedling tiller number is a possible selection criterion to improve seedling establishment of Altai wildrye, Leymus angustus (Trin.) Pilger, an important grass for autumn grazing of beef cattle in semiarid environments. Forty-two half-sib families selected for high seedling tiller number (HTN) and eighteen half-sib families selected for low seedling tiller number (LTN) by four cycles of divergent recurrent selection were compared with four controls, Altai wildrye cultivars Prairieland, Eejay and Pearl, and crested wheatgrass ( Agropyron desertorum (Fisch. Ex Link) Schultes), cultivar Nordan, on dryland and irrigated sites at Swift Current, Saskatchewan, Canada. Seedling tiller count, seedling height, tiller weight and seedling dry-matter yield (DMY) were determined on two plants per plot and DMY was determined for each plot for 2 years post-establishment. HTN half-sib families had more, lighter and shorter tillers than LTN half-sib families. There was a negative correlation ( r =–0·42, P  < 0·01, n =60) between seedling DMY and tiller number. HTN half-sib families had higher DMY in post-establishment years at the dryland site only. Seedling tiller number in Altai wildrye may be related to DMY at sites at which resource availability delays seedling establishment, but selection for HTN will not increase seedling DMY owing to concomitant changes in carbon allocation.  相似文献   

The agronomic value of tetraploid F1 hybrids between potatoes of Group Tuberosum and Group Phureja/Stenotomum     

C. P. Carroll  M. J. De Maine 《Potato Research》1989,32(4):447-456

Summary Selected tetraploid F1 hybrids, between Tuberosum cultivars and 2x Phureja clones, were compared with standard cultivars in randomized trials during the period 1980 to 1986 under conditions which simulated British agricultural practice. Hybrids were superior to standard cultivars in both total and marketable yield, and produced more tubers. We suggest that high yields in the 4x F1 hybrids result from the addition of complementary parental characters, high tuber numbers from Phureja and generally larger mean tuber size from Tuberosum. We discuss the relo of heterosis in an interploidy breeding scheme utilising unreduced male gametes and emphasise the value of tetraploid hybrids between Tuberosum and improved Phureja.  相似文献   

Investigating early vigour in upland rice (Oryza sativa L.): Part II. Identification of QTLs controlling early vigour under greenhouse and field conditions   总被引：1，自引：1，他引：0  

J.E. Cairns  O.S. Namuco  R.Torres  F.A. Simborio  B. Courtois  G.A. Aquino  D.E. Johnson   《Field Crops Research》2009,113(3):207-217

Early vigour is an important characteristic for direct-seeded rice systems. The genetic control of early vigour was studied using a population of 129 backcross lines derived from a cross between Vandana, an improved indica, and Moroberekan, a traditional japonica. Screening was conducted under controlled conditions in greenhouse and field conditions, and indicators of early vigour, including shoot length, shoot biomass, leaf area, number of roots, root biomass, partitioning coefficients, and growth rates, were measured. Phenotypic correlations suggested that traits that were related and combined could be used to define early vigour. Broad-sense heritability ranged from moderate to high. Many regions were identified containing more than one QTL, suggesting that these traits were controlled by pleiotropic and/or closely linked QTLs. Many QTLs were specific to one environment but G × E interaction analysis showed that the main effects of the environment were large. Differences in temperature between experiments resulted in large differences in seedling age when expressed in thermal time. Different genes (QTLs) may be expected to control growth at different time intervals and thus may partly explain the limited agreement between experiments. However, several regions showed co-location of QTLs from more than one experiment. Comparisons with published studies revealed that these regions were previously identified in different genetic backgrounds and could potentially be used as introgression targets in a marker-assisted breeding program to improve germplasm for direct-seeded environments.  相似文献