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101.
新疆不同密度下油葵干物质积累、分配及转移规律的研究 总被引:12,自引:1,他引:12
对新疆南疆地区油葵G101品种4种密度下干物质积累,分配及转移规律研究结果表明:(1)油葵干物质积累动态符合Logistic曲线变化,干物质增长速率呈单峰曲线变化,随密度增加,干物质积累降低,且生育期推迟;(2)净干物质分配随生长中心的转移而发生变化;幼苗期主要分配在叶片中,初蕾至初花期主要分配到茎秆中,花期是并进生长高峰期,以营养器官分配为主,灌浆后转向盘籽中,盘籽成为干物质分配中心;(3)各器官中积累的干物质转向籽粒的比例大小顺序为茎秆>叶片>花盘,转移量占籽粒干物质重量的百分比随密度加大而降低;(4)提出了高产油葵群体有关生理指标。 相似文献
102.
向日葵生物柴油的开发前景 总被引:2,自引:0,他引:2
简述了生物柴油的概况,介绍了杂交油葵的生物学特征,生产效益,以及向日葵生物柴油的特点。在对 向日葵生物柴油研究进行展望的同时,提出发展向日葵生物柴油中存在的问题及解决途径。 相似文献
103.
向日葵是世界四大油料作物之一,列当是对向日葵生长危害极为严重的一类寄生植物,且在全球范围内的发生面积逐年增加,对向日葵产业发展造成严重危害。培育抗列当品种是防治向日葵列当最为有效的途径,也是目前育种家的首要目标。育种家们通过传统的育种方法鉴定抗性基因,培育了一系列向日葵抗列当品种,并在世界范围内向日葵主栽区广泛种植,有效缓解了向日葵列当对该产业的冲击。然而,随着毒力更强的列当生理小种的出现与传播,亟待培育新的、抗性更强的品种。本文综述了新的、毒性强的列当生理小种的结构与分布,对如何利用分子标记辅助选择(MAS)策略提高向日葵的抗性分析,对向日葵抗列当基因序列信息做了归纳总结,对向日葵抗列当育种研究发展前景进行了分析与展望。 相似文献
104.
旨在明确新型杀菌剂啶酰菌胺对向日葵核盘菌生物活性的影响,为其推广应用提供科学依据。以向日葵核盘菌菌丝、孢子和菌核为试材,采用生物测定方法测定啶酰菌胺对向日葵核盘菌菌丝生长、孢子萌发及菌核形成的影响。研究结果表明,啶酰菌胺处理后的核盘菌菌丝生长速率受到抑制,其抑制菌丝生长的EC50为0.2152 μg/mL。随杀菌剂浓度的升高,核盘菌菌丝生长量明显下降,浓度为16.667 μg/mL时,对核盘菌形成菌核数量的抑制率达到84.62%,对核盘菌形成菌核总干重的抑制率达到61.07%。孢子萌发试验结果表明,啶酰菌胺处理后子囊孢子萌发受到抑制,其抑制子囊孢子萌发的EC50为0.056 μg/mL。在浓度为0.267 μg/mL时,孢子芽管伸长抑制率达到78.15%。啶酰菌胺不仅对核盘菌菌丝生长有抑制作用,还可以降低子囊孢子的侵入、阻止子囊孢子萌发形成的芽管在植物组织的继续侵染,有效降低田间土壤中菌核残留量。对向日葵菌核病的防治前景十分广阔,可以作为田间防治向日葵菌核病的轮换药剂。 相似文献
105.
向日葵花期叶片蒸腾特性时空变化及其与环境因子的相关性研究 总被引:1,自引:0,他引:1
向日葵叶片在盛花期的蒸腾特性研究结果表明:向日葵不同叶位的蒸腾作用明显不同。最高峰出现在中上部位叶片。最大值是12叶位,为23.44μE(H2O).m^-2.s^-1。一天中最高峰时间在12:30,不同叶位的蒸腾速度的日变化均呈单峰曲线,环境因子对蒸腾作用的影响不是单一的直接作用。并且每种因子对蒸腾作用的影响在日变化中明显不同。早8:30光量子通量密度和叶片温度与蒸腾作用均呈极显著正相关,相对湿度在早8:30和上午10:30都呈极显著正相关,其他时间均呈不显著正相关。在上午10:30和14:30时。光量子通量密度与蒸腾作用呈负相关。中午12:30和晚上18:30呈不显著正相关;叶片温度在上午10:30与蒸腾作用呈负相关外,其他时间均呈不显著正相关。 相似文献
106.
对食用型向日葵籽实性状遗传和选择研究中,其主要性状的遗传力为:籽实长度>百粒籽实重>籽实厚度>籽实宽度。对控制性状的最少差异主效基因数,籽实长度为4—5对,其余3个性状为1—2对。在选育食用型自交系时,组合的选配应以食用型和中间型为杂交亲本,早世代选择以籽实长度为主,F_4后代对子实的长、宽、厚三性状同等注意,并辅之以百粒籽实重。 相似文献
107.
向日葵耐盐性比较及耐盐生理指标选择 ) 总被引:19,自引:1,他引:19
植于蛭石中的3个向日葵品种用0% (CK) 、0. 3%和0. 9% NaCl Hoagland溶液胁迫处理, 20d和40d分别 测定各种指标。结果表明,DK119较以色列H1和陇葵杂1号具有较强的耐盐性; 0. 3% NaCl和短时间(20d)处理, 向日葵的叶面积和膜透性相对值可作为评价植株耐盐性的指标,处理时间延长至40d,膜透性相对值失去对植株耐 盐性评价的意义;脯氨酸含量、叶绿素含量和光合速率亦不能作为评价植株耐盐性指标;当NaCl浓度为0. 9%时, 任何指标都失去评价意义。 相似文献
108.
Johnson Kayode Adesodun Florence Alaba Olowokere Adewole Oladipupo Ismail Ayodeji Obaloluwa Adekunle Juliana Abimbola Osore 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):14-22
Short-term effect of organic and inorganic amendments on soil physical quality (SPQ) is marked when dealing with tropical soils which are naturally exposed to a high risk of water erosion. This study assessed the suitability of Tithonia diversifolia (Mexican Sunflower) when incorporated as green manure (GM) and also composted with poultry manure (PM) and other organic-based and inorganic fertilizers to improve some hydraulic properties of an Alfisol subject to excessive drainage. Treatments applied include fresh T. diversifolia (GM), PM, T. diversifolia composted with PM, organo-mineral fertilizers (OMF), neem fertilizer (NF), inorganic fertilizer (20-10-10 NPK), and control in a randomized complete block design and replicated four times. Soil samples were collected at 0–20 cm depth to determine near steady-state infiltration rates (Is), sorptivity, transmissivity, saturated hydraulic conductivity (Ks), macroporosity (MacP), microporosity (MicP), air capacity (AC), and relative water capacity (RWC). The Is rates were significantly (P ≤ 0.05) reduced to optimum range with the addition of the organic fertilizers over very high value (128.7 cm hr?1) observed for control. Whereas, Ks was enhanced in the order: GM > compost (CP) > NF > inorganic fertilizer > control > organo-mineral fertilizer > PM. Sorptivity and transmissivity were highest in control and inorganic fertilizer plots, indicating that the addition of organic fertilizers lowered these parameters while MacP, MicP, AC, and RWC were generally increased with the addition of organic-based and inorganic fertilizers. Specifically, NF increased MicP by 34% over control. Values for RWC which were within the optimum range (0.60–0.70) were only obtained with NF (0.74), OMF (0.72), NPK (0.70), and GM (0.60). The SPQ parameters assessed in this study were enhanced by the addition of fresh T. diversifolia applied as GM and CP compared to other treatments. Therefore, T. diversifolia usually burned by farmers should instead be incorporated into the soil as manure. 相似文献
109.
《Plant Production Science》2013,16(1):23-31
AbstractWe examined 50 cultivars of sunflower (Helianthus annuus L.) for their resistance to birds in a field experiment to find parental plants for breeding. Two cultivars, Armarvirskij3497 (from Russia) and Line-41 (from Myanmar), had bird-resistant characteristics. The laboratory bird feeding test indicated that the factors associated with bird resistance were globular seed shape and heavy seed coat, because the main bird feeding on sunflower, oriental greenfinch Carduelis sinica, is relatively small and have difficulty pecking large and globular seeds. Although the two cultivars had unfavorable characters such as low tolerance to lodging and late maturity, the oil contents of their seeds was not significantly lower than that in the susceptible cultivar (63M80). The present findings suggest that Armarvirskij3497 and Line-41 are candidate parental materials for breeding bird-resistant sunflower cultivars without losing seed oil productivity. 相似文献
110.
Ruey-Shyang Chen Chishih Chu Chi-Wei Cheng Wen-Yu Chen Jwu-Guh Tsay 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(1):1-8
Powdery mildew can be found in most sunflower fields during the winter season in Taiwan and causes severe yellowing on the
blade, petiole, stem, and calyx, as well as serious defoliation. Two types of powdery mildew fungi isolated from sunflower
leaves showed variable status for fibrosin bodies. But only the cleistothecium of Podosphaera xanthii, one of the pathogens causing this disease, was observed on samples from Chungpu County at the beginning of 2005. With a
species-specific primer pair, PN23/PN34, no specific PCR product was amplified from the pathogen’s genomic DNA. Based upon
the ITS sequence of rDNA, three PCR primer sets (S1/S2, G1/G2, and L1/L2) specific to P. xanthii, Golovinomyces cichoracearum and Leveillula taurica, respectively, were designed to detect and differentiate pathogens causing powdery mildews on sunflower. Only the primer
pairs S1/S2 and G1/G2 could amplify PCR products, with product sizes of 454 and 391 bp, respectively. Four samples of fungal
DNA were subjected to a multiplex PCR amplification with primer pairs S1/S2 and G1/G2; P. xanthii and G. cichoracearum were successfully detected. These results suggest that the multiplex PCR method is a rapid, simple, and effective technique
to detect and differentiate powdery mildews, for example P. xanthii and G. cichoracearum, found on sunflower. With morphologic characteristics, ITS sequence analysis and pathogenicity testing, P. xanthii and G. cichoracearum, the first case, are two powdery mildews on sunflower in Taiwan. 相似文献