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研究药用白芍的传粉特性,为药用白芍的资源保护和优良品种选育提供科学依据。采取11种不同的处理方式,比较不同授粉方式的结实率和结实质量。芍药的自然结实率低;芍药的异株异花传粉可提高芍药的结实率达3倍,自然生长的花人工给予授粉结实率可提高近4倍;芍药的同株自花直接套袋、同株自花人工授粉和同株异花人工授粉的结实率均不高,分别为0.17%、0.84%、1.16%;去雄和去花冠处理结果表明芍药以异花传粉为主,同时花冠在传粉结实中也起到一定的作用。芍药具有微弱的自交性,芍药以异株异花授粉为主;异株异花授粉,可提高芍药的结实率;同时对芍药的结实率低的原因给以初步分析整理。 相似文献
94.
J. R. Tueche S. Hauser B. Banful G. Cadisch 《Archives of Agronomy and Soil Science》2013,59(7):789-803
Information on the effects of soil physical properties on plantain yield is rare. A factorial trial was conducted in three southern Cameroonian villages comparing four cropping systems comprising: two planted legumes, (1) Flemingia macrophylla and (2) Pueraria phaseoloides; a crop, (3) hot pepper; and (4) natural regrowth, all planted to plantain established in old forest versus young bush fallow. Initially, bush fallow had significantly higher sand content, mean weight diameter (MWD) and proportion of macroaggregates, but lower clay content and lower proportions of mesoaggregates and microaggregates than forest soil. Between 2002 and 2006, clay and silt content, MWD, geometric mean diameter and the proportion of macroaggregates increased, whereas sand content, bulk density, and the proportions of mesoaggregates and microaggregates decreased in all villages, fallows and cropping systems. Changes in aggregate stability parameters were greater in forest than in bush fallow at Ngoumou and Mfou, and greater in the F. macrophylla and natural regrowth systems than in the pepper and Pueraria systems. In Ngoumou and Nkometou, available water capacity increased. Plantain fresh-bunch yield was unaffected by village, fallow and cropping systems, and was not correlated with soil physical properties or their changes. 相似文献
95.
Modelling species and spacing effects on root zone water dynamics using Hydrus-2D in an Amazonian agroforestry system 总被引:3,自引:0,他引:3
Modelling the root zone water dynamics in a tree crop agroforestry system is a useful approach to understanding small-scale effects in tree crop systems and may be helpful for optimizing tree spacing in agroforestry system planning. The agroforestry system in this study consists of the species Theobroma grandiflorum (Willd ex Spreng) Schum (Cupuaçu), Bactris gasipaes H.B.K. (peach palm) and the cover crop Pueraria phaseoloides (Roxb.) Benth (Pueraria). The soiltype is an oxisol. Calibration was conducted for each of the three species separately. Calibration results show good conformity between simulated and measured data. Simulated scenarios examine the influence of different spacing between trees on root water uptake, evaporation and drainage. Mean interception and crop factors of the whole flow region vary with spacing or are held constant to examine below-ground effects only. Also a fictitious scenario of an older agroforestry system with deeper roots is calculated. In order to overcome restrictions of the computer program Hydrus-2D, correction factors in the root zone were introduced and a calculation scheme for root water uptake of a flow subregion was developped. Below-ground effects of spacing between trees are not or almost not present, but the depth of the tree roots has a significant influence on root water uptake, evaporation and drainage. When mean interception and crop factor vary, drainage increases and root water uptake decreases slightly with spacing. The modelling approach has been found promising for optimizing agroforestry systems although it can only be seen as a first beginning. In an agroforestry systems under drier conditions differences in results will probably be larger. 相似文献
96.
We studied the effect of bacteria involved in rock phosphate (four isolates), iron phosphate (two isolates), and aluminium phosphate (two isolates) solubilization, and two phytate-mineralizing bacteria in terms of their interaction with two Glomus spp. on Pueraria phaseoloides growth and nutrition. The plant —Rhizobium sp. — mucorrhiza symbiosis system may increase in yield and nutrition in association with specific rhizosphere bacteria that solubilize calcium, iron, and aluminium phosphates. No benefit from phytate-mineralizing bacteria was found under these experimental conditions. P. phaseloides growth responses were influenced in different ways by specific combinations of the selected bacteria and arbuscular mycorrhizal fungi. Considerable stimulation of nutrient uptake was observed with fungus-bacteria combinations of Azospirillum sp. 1, Bacillus sp. 1 or Enterobacter (spp. 1 or 2) associated with G. mosseae. The fact that Bacillus sp. 1, a calcium-phosphate solubilizing isolate, positively interacted with G. mosseae and negatively with G. fasciculatum is an indication of specific functional compatibility between the biotic components integrated in the system. From our results, the interactions between bacterial groups able to solubilize specific phosphate and mycorrhizal fungi cannot be interpreted as occurring only via P solubilization mechanisms since no generalized effect was obtained. Iron-phosphate solubilizing microorganisms were more active alone than in dual associations with Glomus sp., but the aluminium-phosphate dissolving isolates positively interacted in mycorrhizal plants. Further work is needed in this area in order to elucidate the mechanisms that affect rhizosphere microorganism interactions. G. mosseae was more effective but less infective than G. fasciculatum in most of the combined treatments. 相似文献
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利用饲料分析技术及氨基酸分析仪对桑(Morus alba)、苎麻(Boehmeria nivea)及葛藤(Pueraria lobata)几种南方非常规饲料作物中的常规营养成分及氨基酸组成进行了分析。结果发现,1)桑、苎麻及葛藤中的蛋白质含量较高,尤其是苎麻,蛋白质含量高达22.38%,但同时其纤维含量也较高;2)葛藤的总能值相对较高,达17.17 MJ·kg~(-1);3)桑、苎麻及葛藤中的氨基酸含量丰富,尤其是植物性第一限制性氨基酸——赖氨酸的含量较高,为0.65%~0.89%,且总必需氨基酸的含量为5.10%~7.40%。因此,桑、苎麻及葛藤可以作为南方的优质牧草资源进行开发利用。 相似文献
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Summary A polyacrylamide gel electrophoresis procedure was developed for discriminating cultivars of the forage legume Pueraria phaseoloides on the basis of the patterns of cotyledon proteins. The genotypic marker proteins were extracted with 5M acetic acid and electrophoresed at pH 3.1 in aluminum lactate buffer. The procedure gave highly reproducible discrimination of ten selected cultivars. 相似文献