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11.
周德宝 《安徽农业科学》2010,38(31):17382-17383,17386
以拟南芥为例,阐述了开花过程中基因调控方面的最新进展。  相似文献   
12.
The influence of flower position on the inflorescence on opening day, gender, and petal persistence was studied in three olive cultivars: Manzanillo, Mission, and Frantoio. In each cultivar, 45 inflorescences were checked every morning from flower opening to petal fall. Perfect flowers opened mainly in the beginning of the flower opening period, and staminate flowers opened later. Flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than the flowers located on the secondary branches. Flower position had also a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. Among the primary branches, the branch arising immediately next to the terminal flower had the latest flowers to open and the lowest percent of perfect flowers. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal half of 120 inflorescences, on which the flowers tend to be perfect, in three trees of Manzanillo were removed about 1 month before full bloom. There was a highly significant effect on the percent of perfect flowers that opened on the proximal half. Flower competition may be a reason for pistil abortion in flowers located on secondary branches.  相似文献   
13.
槟榔花果中槟榔碱含量的时空变化   总被引:1,自引:0,他引:1  
采用药典法对槟榔不同发育时期花序材料的不同部位进行槟榔碱含量检测。结果表明:成熟种果胚乳的槟榔碱含量最高,而果皮的含量最低;不同时期花序/果穗的相同部位间槟榔碱含量存在显著差异,同一时期花序/果穗的不同部位间不存在显著差异。  相似文献   
14.
根域加温对促成栽培绯红葡萄生长发育的影响   总被引:6,自引:0,他引:6  
连续2年以“Y”形整枝的2年生葡萄绯红(VitisviniferaL.cv.Cardinal)品种为试材,在超早促成栽培的早期进行根域土壤加温处理,探讨其对根域土壤温度、树体发育和果实品质的影响。结果表明,根域加温提高促成栽培早期土壤温度约10℃,各物候期均早于未加温处理2~5d,新梢生长好,叶面积大;花穗发育好,单株果穗数显著增加;果汁含糖量和果皮花青素含量增加,可滴定酸降低,果实品质提高;果粒重量、果穗重量和单株产量均显著高于未加温处理。并就根域加温效果的形成机理进行了探讨。  相似文献   
15.
万寿菊的组织培养和瓶苗开花研究   总被引:4,自引:0,他引:4  
对矮生杂交万寿菊组织培养研究表明:带1个腋芽的无菌苗茎段在MS+0.05mg/LNAA+0.2mg/LBA培养基上35d均可诱导出芽,芽诱导率达100%;继代培养时,MS+0.1mg/LBA是万寿菊较适宜的增殖培养基,平均增殖系数可达10.7,生根率为100%。将带有2个腋芽和1个顶芽的茎段接种到MS+0.05mg/LBA+0.4mg/LPP。培养基上,20d后,就能长成1株有根、茎、叶和花蕾、花朵的完整植株。  相似文献   
16.
17.
粉皮 石榴花芽分化研究   总被引:2,自引:0,他引:2  
将‘粉皮’石榴的花芽分化分为7个时期,其中,胚珠分化期尤为关键。在安徽怀远,花芽的形态分化从6月上旬开始,历时2~10个月不等。花芽分化既连续,又表现出3个高峰期,即当年的7月上旬、9月下旬和4月上、中旬。花芽以花瓣期或之前的时期越冬。与花芽分化高峰期相对应的是3个开花高峰期,称为“头花”、“二花”和“三花”。石榴花芽分化要求较高的温湿条件。最适温度为月均温20±5℃。低温是石榴花芽分化的限制因素,月均温低于10℃时,花芽分化逐渐减弱直至停止。文中还讨论了石榴花序的类型等。  相似文献   
18.
立冬本龙眼结果母枝性状与开花结果的关系   总被引:3,自引:0,他引:3  
通过两年的观测统计,分析了晚熟龙眼立冬本秋、冬梢不同抽生期及结果母枝生长状况对开花结果的影响;提出立冬本龙眼初结果树两个最佳放梢时期分别为8月中旬至9月上旬、10月上旬至10月下旬;优良结果母枝应选择粗度0.70~1.09cm的枝梢为宜;统计分析表明,结果母枝粗度与穗坐果数呈极显著正相关,而结果母枝长度、复叶数与穗坐果数的相关不显著,说明结果母枝的粗度对坐果的影响最大,是立冬本优良结果母枝的主要衡量指标;立冬本初结果树在12月上旬之前抽发的枝梢仍可开发结果,但8月上旬、12月上旬两个时期所抽枝梢的结果性能差,生产上应予疏除。  相似文献   
19.
以豫麦49、豫麦18为对照,对豫麦66及其优系和矮早系的花器构造、散粉特性和穗部特征进行了研究。结果表明:与对照相比,豫麦66各系的花药大,穗子较长,开颖角度较大,开花持续期较长,而且穗粒数、穗花数、外露花药数、中部穗粒数都较多,是理想的杂交小麦父本材料。  相似文献   
20.
The population density of Closterotomus trivialis (Costa) and its damage potential were studied in citrus and olive orchards of Crete. C. trivialis was found to be most abundant in wild radish Raphanus raphanistrum L., annual mercury Mercurialis annua L., Urtica sp. and upright pellitory Parietaria officinalis L. compared to mallow Malva sylvestris L., prickly goldenfleece Uropermum picroides (L.), sowthistle Sonchus oleraceus L., citrus or olive trees. Its damage potential on the setting of olive fruit was investigated at the early inflorescence stage. When 1, 5 or 10 adults of C. trivialis were enclosed with stems at the 55th and 57th phenological growth stages, the number of fruits was significantly reduced compared to controls.The developmental biology of individuals of C. trivialis was studied on R. raphanistrum at seven constant temperatures 15, 20, 25, 30, 32.5, 35 and 37 °C, under laboratory conditions. No nymphs survived above 35 °C. The highest nymph to adult survival (89.6%) was found at 20 °C and the lowest (40.6%) at 32.5 °C. Mean developmental time as well as adult longevity decreased with increasing temperature. The developmental time from 1st nymphal instar to adult ranged from at least 9.0 at 32.5 °C to 27.8 days at 15 °C. The adults lived from 2.9 days at 32.5 °C to 45.3 days at 15 °C. It required 212.7 degree-days to complete development above a minimum threshold of 7.72 °C as estimated by linear regression and 8 °C as estimated by nonlinear model. The importance of these findings in the management of this species through the prediction of its seasonal appearance is discussed.  相似文献   
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