滇一型水稻雄性不育系性回复的初步研究   总被引：4，自引：0，他引：4  

谭亚玲  陈丽娟  谭学林  张忠林  黄大军 《杂交水稻》2001,16(5):48-49

对滇一型水稻不育系中可育株的育性，出现频率及其对不育系恢复能力的研究结果表明：滇一型水稻不育系中存在少数可育株，依据对不育系恢复能力的不同，可育株分为无恢复力的恢复力两种类型，前者来源来保持系混杂，后者可能是由于雄性不育系不育基因的回复突变所致。  相似文献   

敕勒川草原生态恢复群落动态演替     

王君芳  韩国栋  王召明  云锦风  秦洁 《草地学报》2022,30(11):3090-3097

为揭示退化草原生态恢复过程群落动态变化规律,在阴山南麓敕勒川草原开展生态恢复试验,通过连续10年监测,研究不同年际退化草原生态恢复物种数、个体数、地上生物量和物种多样性变化,比较人工恢复、自然恢复与原生植被之间的物种多样性差异。结果表明：随着恢复时间的增加,草地Margarlef指数、Shannon-Wiener指数、Simpson指数均出现先增加后减少再稳定的趋势,而Pielou均匀度指数呈现先减少后增加趋势;不同恢复方式下,自然恢复样地和原生样地多样性指数均显著高于人工恢复样地(P<0.05)。人工干扰引导自然恢复能够促进退化草原生态恢复,提高植物多样性,加速恢复演替进程。  相似文献   

Host and virus effects on reversion in cassava affected by cassava brown streak disease          下载免费PDF全文

I. U. Mohammed  S. Ghosh  M. N. Maruthi 《Plant pathology》2016,65(4):593-600

The phenomenon of virus‐infected plants naturally recovering health is known as ‘reversion’, and is a type of resistance mechanism exploited in some crop plants for disease control. Various parameters were investigated that affect reversion from cassava brown streak disease (CBSD) in three cassava varieties (Albert, Kaleso and Kiroba) that differ in levels of resistance to the disease. Cassava plants were inoculated by grafting with two virus species (Ugandan cassava brown streak virus, UCBSV and Cassava brown streak virus, CBSV) that cause CBSD, and the plants grown from them were subsequently assessed for reversion. The rate of reversion depended on the cassava variety, virus species, and the length and position of the stem cuttings used. A significantly high proportion of progenies were virus‐free (reverted) for the resistant variety Kaleso (64·1% for UCBSV and 54·9% of CBSV), compared to the tolerant variety Kiroba (56·7 and 45·5%) and the susceptible control Albert (38·9 and 35·1%). The highest number of virus‐free plants was generated from short 10 cm long cuttings (e.g. 60·1% for Kaleso for CBSV) compared to 20 cm long stem cuttings (e.g. 21·4% for Albert). Cuttings taken from upper stems of diseased plants produced most virus‐free progenies compared to middle and lower parts. More than 50% virus‐free plants were obtained in the resistant and tolerant varieties. This is a highly valuable finding and could be exploited for developing strategies to control the current CBSD epidemic in eastern and central Africa.  相似文献   

Proteomic analysis of differentially expressed proteins in longan flowering reversion buds     

Sisi Chen  Hao Liu  Wei Chen  Dongli Xie  Shaoquan Zheng 《Scientia Horticulturae》2009

A proteomic approach was taken to compare the proteomes of normal flowering buds and flowering reversion buds in longan (Dimocarpus longan Lour. cv. Longyou). Two-dimensional gel electrophoresis (2-DE), coupled with mass spectroscopy and protein database searching, recognized 18 proteins that were differentially expressed in flowering reversion buds. Eleven of these were down-regulated, whereas seven were up-regulated. A subset of 13 proteins was identified by MALDI-TOF-TOF/MS and classified into regulatory proteins (kinase, 20S proteasome alpha 6 subunit, putative alpha 7 proteasome subunit, auxin-induced protein, and abscisic stress ripening-like protein), antioxidant-related proteins (Chain A, GDP-mannose-3′,5′-epimerase, putative lactoylglutathione lyase, and Chain A, ascorbate peroxidase), pollen fertility-related proteins (putative leucoanthocyanidin reductase 2, and putative isoflavone reductase), photosynthesis-related proteins (large subunit, ribulose-bisphosphate carboxylase–oxygenase), and molecular chaperones (disulfide isomerase). Among them, regulatory and antioxidant-related proteins accounted for almost two-thirds of these proteins, suggesting that they may play a more important role in bud differentiation. Identification of these proteins provides insights that may lead to a better understanding of the molecular basis for flowering reversion in longan.  相似文献   

半湿润地区改良风沙土土壤性质研究   总被引：12，自引：1，他引：12  

冯起 《水土保持通报》1998,18(4):1-6

分析了改良前后半湿润沙荒地的机械组成,土物理性状,化学性质和土壤水分特征的变化,结果表明半湿润沙地改良后,０－１００ｃｍ土层的细沙粒和粉沙粒数量增加,粗沙粒数量减少;土壤抗风蚀性增加６－１０倍;土壤保水性能大大增加;壤质沙土的土壤水分含量提高了５０％－１００％,有机质增加了１－３倍。证明了半湿润风沙土地逆转的可能性。  相似文献   

Induction of cytoplasmic male sterility and fertility reversion by mutagenesis; negative evidence from a study on sugar beet     

Timothy Brears  David M. Lonsdale 《Euphytica》1990,46(2):169-173

Summary Attempts have been made to induce cytoplasmic male sterility (cms) and cytoplasmically inherited fertility reversion in sugar beet using various mutagenic agents by repeating techniques previously described. Despite the previous report of successful induction of cms and reversion at very high frequency it was not possible to repeat this success. Analysis of M₂ plants at the DNA level demonstrated no major rearrangements in chloroplast or mitochondrial DNA.  相似文献   

应用微卫星标记定位水稻恢复系密阳46的主效和微效恢复基因   总被引：8，自引：1，他引：7  

李广贤  屠国庆  张克勤  姚方印  庄杰云 《中国水稻科学》2005,19(6):506-510

应用由704个株系组成的珍汕97A/(珍汕97B/密阳46)F6测交群体,针对水稻第10染色体和第1、11染色体短臂构建了微卫星标记连锁图谱,检测到控制野败型细胞质雄性不育育性恢复的4个QTL,其中位于第10染色体长臂中下部的Rf4具有主效效应,位于第1染色体短臂的Rf3具有较大效应,位于第10染色体长臂近着丝粒处的qRf10和第11染色体短臂近着丝粒处的qRf11表现出微效作用。研究还表明,在主效基因Rf4存在时,其他3个基因仍具有提高结实率的作用,但在Rf3和Rf4同时存在时,qRf10和qRf11的效应不明显。  相似文献   

竹子开花人工诱导与逆转研究现状及前景   总被引：6，自引：0，他引：6  

谢寅峰  张春霞  丁雨龙 《浙江林学院学报》2000,17(4):436-440

竹类植物是重要的禾本科经济植物。由于开花周期长且难以预测,大多数竹种终身一次开花并导致死亡,具有自然结实率低等独特的开花习性,使得竹子开花及相关研究受到了很大的限制。通过竹子开化的人工诱导与逆转的研究,不仅可以人工获取难得的竹子种子,更为竹种分类鉴定、杂交遗传能种和开花机理等多方面研究工作提供了良好的基础,其理论意义和应用价值都十分重大。迄今为止,印度和比利时等国研究人员已在至少８个竹种中成功诱导  相似文献   

Sustainable Forest Management in Tropical Rain Forests     

《Journal of Sustainable Forestry》2013,32(3-4):93-118

Abstract

In planning of sustainable forest management, economic, environmental and social demands often conflict. Forest management in Southeast Asian tropical dipterocarp forests has been particularly biased towards maximizing immediate economic return from extensive logging. Overexploitation and other forms of uncontrolled land use within these forests have led to the situation where the remaining natural forests, most of them in Indonesia, will be liquidated within the next 10-15 years at the current rate of deforestation. In this paper we present an approach for sustainable forest management planning in which economic, environmental and social sustainability are considered simultaneously in order to define an optimal management strategy from a set of available alternatives.

We carried out a case study within a rain forest logging concession in Indonesian Borneo by using a participatory planning approach involving interviews of the local people, environmental assessment and economic analyses. We used the Analytic Hierarchy Process (AHP) method for resource allocation and priority setting in order to identify an optimal strategy which yields a sustained economic output from timber production, while at the same time being environmentally and socioculturally sustainable. Despite their relatively high costs, strategies involving selective harvesting combined to complete restoration of original dipterocarp stock in logged-over areas were superior in terms of economic, environmental and social sustainability. Priorities set by local communities for the strategies to meet their socioeconomic and cultural needs coincide well with those ensuring the restoration and biodiversity.  相似文献   

Selection for resistance, reversion towards susceptibility and synergism of chlorantraniliprole and spinetoram in obliquebanded leafroller, Choristoneura rosaceana (Lepidoptera: Tortricidae)     

Sial AA  Brunner JF 《Pest management science》2012,68(3):462-468

BACKGROUND: Obliquebanded leafroller, Choristoneura rosaceana (Harris), is an economic pest of pome fruits throughout North America. Repeated applications of broad‐spectrum insecticides have resulted in the development of resistance, cross‐resistance and multiple resistance in this pest. Studies were conducted to determine the possibility of resistance evolution, stability of resistance and the effect of metabolic synergists on toxicity of new reduced‐risk insecticides chlorantraniliprole and spinetoram in C. rosaceana. RESULTS: Larvae of C. rosaceana were selected for resistance to chlorantraniliprole and spinetoram in the laboratory. Significant levels of resistance to each insecticide were observed after 12 generations of selection. In the absence of selection pressure, susceptibility of a subset of larvae from both chlorantraniliprole‐ and spinetoram‐selected populations reverted to preselection levels after five and six generations respectively, indicating that resistance to both chlorantraniliprole and spinetoram was unstable in C. rosaceana. In synergist bioassays performed after 12 generations of selection, S,S,S‐tributylphosphoro trithioate (DEF) and piperonyl butoxide (PBO) synergized the toxicity of chlorantraniliprole and spinetoram respectively, suggesting the involvement of esterases in chlorantraniliprole resistance and the involvement of mixed‐function oxidases in spinetoram resistance. CONCLUSION: These findings suggest that chlorantraniliprole and spinetoram could be incorporated into C. rosaceana resistance management programs by using rotational strategies. Copyright © 2011 Society of Chemical Industry  相似文献