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91.
92.
为了解二型花雌、雄蕊发育进程及内源激素对长、短花柱生长发育的影响,以蓝花丹(Plumbago auriculata Lam.)为材料,观察分析了长花柱(L型)、短花柱(S型)花朵内雌、雄蕊的发育特征,并分别检测了L、S型花柱中的内源激素水平。结果显示:蓝花丹雌、雄蕊发育进程基本符合逻辑斯蒂变化曲线,并可划分为5个时期,即T1初始发育期、T2转折期(一)、T3快速发育期、T4转折期(二)、T5平稳发育期;在整个发育进程中,L型花朵中雌蕊的生长速率始终高于雄蕊;S型花朵中雌蕊的生长速率在T3期由快转慢,导致T3~T5期雌蕊的生长速率始终低于雄蕊,从而形成了雌蕊低于雄蕊的短花柱特征。这说明花柱的分化是在二型花雌、雄蕊快速发育的T3期开始出现,并逐渐形成花柱异长植物最显著的花部形态特征。IAA、IPA和GA含量均在T1~T3期增加、T4~T5期降低,且在L型花柱中的含量始终高于S型,而ABA含量的变化趋势与这3种生长促进类激素相反,说明在蓝花丹花柱发育过程中,IAA、IPA和GA可能参与调控花柱的伸长生长,而ABA主要在发育后期促使花柱成熟。  相似文献   
93.
The phenetic variation inL. tenuifolium s.l. was assessed using multivariate analyses of 27 characters found to be variable within the species. These results are discussed and interpreted in the context of the reproductive biology, chromosome number and ecological responses of the taxa. Evidence suggests that both the self-compatible and tetraploid races were derived independently from a self-incompatible, diploid type. Although no taxonomic scheme is compatible with all of the evidence presented, the study supports a recent decision to recognize four taxa at subspecific level.  相似文献   
94.
Promotion of root elongation by phosphorus deficiency   总被引:12,自引:0,他引:12  
Decrease of culture solution pH and increase in cation/anion ratio in the plant were observed when horsegram (Macrotyloma uniflorum (Lam.) Verdc.) was grown in solution culture deficient in phosphorus. The effux of H+ from the roots of –P plants was observed in bromocresol purple agar. The length of root cells was considerably increased by –P treatment. Thus a close correlation between H+ excretion, length of the root cells and root elongation in response to P deficiency was established.  相似文献   
95.
甘薯叶的挥发性化学成分的研究   总被引:2,自引:0,他引:2  
本文对甘薯(Ipomoea batatas Lam.)叶中挥发性化学成分采用气相色谱/质谱法进行了定性、定量分析,从92个色谱峰中鉴定出17个化合物,含量占总组成的95.09%,主要成分为棕榈酸(占47.62%)相亚麻油酸(占16.62%)。  相似文献   
96.
The population biology ofAquilaria malaccensis, one source of gharu, and Cinnamomum mollissimum, one source of wild cinnamon, was studied in a 50 ha permanent plot of primary rain forest in Malaysia. Median diameter growth rates of 0.22 cm yr-1 and 0.1 cm yr-1 should not be prohibitive of economic exploitation, and suggest that the trees could be grown commercially. However, the natural densities were between 2 and 3 trees over 1 cm d.b.h. per ha, which is roughly the median for all trees in the plot, would preclude economic exploitation of these natural populations. The economics of harvesting natural populations is considered in a preliminary fashion by allowing favorable assumptions of quantity and quality of production. The price likely to be fetched from either a first time extraction (on the order of US$10.00 per ha) or from sustained production (on the order of USThe population biology ofAquilaria malaccensis, one source of gharu, and Cinnamomum mollissimum, one source of wild cinnamon, was studied in a 50 ha permanent plot of primary rain forest in Malaysia. Median diameter growth rates of 0.22 cm yr-1 and 0.1 cm yr-1 should not be prohibitive of economic exploitation, and suggest that the trees could be grown commercially. However, the natural densities were between 2 and 3 trees over 1 cm d.b.h. per ha, which is roughly the median for all trees in the plot, would preclude economic exploitation of these natural populations. The economics of harvesting natural populations is considered in a preliminary fashion by allowing favorable assumptions of quantity and quality of production. The price likely to be fetched from either a first time extraction (on the order of US10.00 per ha) or from sustained production (on the order of US10.00 per ha) or from sustained production (on the order of US0.10 per ha per yr), are too small to be of interest as single-product schemes, and are negligible compared to the extraction of multi-species crops of timber. However, it is possible that by combining multiple products under a “High Diversity Forestry” scheme, one could increase the density of harvestable products, reduce the unit cost of labor and improve the economic portrait. La poblacion dinamica de algunos arboles tropicales. La población biológica deAquilaria malaccensis, un original de gharu, yCinnamomum mollissimum, un original del cinnamon salvage, ha sido estudiado en 50 ha en un terreno primario permanente de lluvia tropical en. Con un índice de crecimiento de medio dimetro 0.22 cm yr-1 0.1 cm yr-1 no deberia prohibirse la explotación económica, y se segiuere que los árboles pueden ser cultivados comercialmente. De cualquier manera, la densidad natural siendo aproximadamente entre 2 y 3 árboles per encima de 1 cm dbh per ha, lo cúal es un promedio de todos los árboles en el terreno, esto representa un impedimento a la explotacion económica de la población natural. La economía de la población natural de recolección de la cosecha está considerada como una moad preliminar por permitirse favorablemente la supuesta cantidad y calidad de productión. Los precios problemente alcanzen, bien sea, la primera vex de su extracción sobre el pedido de US10.00 per ha o desde una continua productión ininterrumpida, (sobre un pedido US10.00 per ha o desde una continua productión ininterrumpida, (sobre un pedido US0.10 per ha per yr), siendo demassiado peque?o para ser de interés tal proyecto comoproducto-unico, y son insignificantes comparados con la extracción de multiples especies de semillas de madera. De caulquier manera esposible que sepueda combinar los multiple productos en el proyecto de “Alta Diversidad Forestal,” uno puede la un puede incrementar la densidad de la productión de la cosecha, reduciendo el costo de mano de obra por unidad y mejorando la imagen económica.  相似文献   
97.
Fusarium wilt, a disease caused by Fusarium oxysporum f.sp batatas (Fob) is an important disease in sweet potato production. Using endophytic bacteria for biological control of sweet potato diseases is one of the important ways. A Bacillus subtilis with antagonistic effect on Fusarium wilt of sweet potato was isolated from soil by confrontation culture. According to the biological characteristics, 16S rDNA sequence analysis, and physiological and biochemical analysis, the Bacillus subtilis HAAS01 was named. A pot experiment was conducted for the biological control experiment of strain HAAS01, and the endogenous hormone content, antioxidant enzyme activity, soluble protein content, and related gene expressions of sweet potato plants were detected. The results showed that the HAAS01 strain could promote the production of endogenous hormones and resist the infection of plant diseases together with defensive enzymes and upregulation of related gene expressions. In summary, Bacillus subtilis HAAS01 was effective in controlling Fusarium wilt of sweet potato and has potential for application and development.  相似文献   
98.
比较了4个水分梯度3年生台湾青枣(Zizyphus mauritiana Lam.)的树高生长动态、地径生长动态、新梢生下量、枝粗生长量、叶面积、叶面积指数、座果率、平均株产量、叶片含水率和根系含水率等,通过主成分分析法和R型因子综合分析法确定了适合台湾青枣生长的最优土壤含水率。结果表明:第3种水分处理(土壤含水率为田间持水量的70%-85%)的台湾青枣对水分的响应最好,对水分的响应排序值是56.147;其次是第4种水分处理(土壤含水率为田间持水量的85%-100%),其值为41.506;最后是第1种水分处理(土壤含水率为田间持水量的40%-55%),其值为34.545。由此可以得出,在金沙江干热河谷地区种植台湾青枣的最佳土壤水分是土壤含水率达到田间持水量的70%-85%。  相似文献   
99.
We have used two aminoglycosides, G418 and paromomycin, to develop a reliable selection system fornptll transgenic sweet-potato (Ipomoea batatas (L.) Lam.). Embryogenic calli derived from shoot apical meristems were bombarded with gold particles coated with pCAMBIA2301, which contained thenptll andgusA genes. When compared on a kill curve that was based on calli proliferation and cell viability, G413-selection proved to be more efficient and had fewer escapes than kanamycin. These bombarded expiants were then selected on G418-containing media. The total time required from bombardment to plant establishment in soil was seven to nine months. Multiple copies of the transgene were integrated into the sweetpotato genome. Northern analysis confirmed transgene expression in the regenerated plants, and a paromomycin assay demonstrated that thenptll gene was functionally expressed in transformed sweetpotato. These molecular analyses and assays all showed that selection with G418 and paromomycin is reliable. So far, we have produced 69 transgenic events with this system, at a transformation frequency of approx. 1.1%. That efficiency is based on the number of transgenic plants obtained and the amount of calli bombarded. Thus, this selection method that combines G418 with paromomycin is now available for selectingnptll transgenic sweetpotato.  相似文献   
100.
无机盐、激素与真菌联合诱导土沉香抗逆能力的研究   总被引:1,自引:0,他引:1  
为了探究无机盐、激素与真菌联合诱导土沉香(Aquilaria sinensis)抗逆性及其与结香前期木芯变色长度之间的相关关系,以10年生土沉香为材料,采用均匀试验设计,开展了3种无机盐、3种激素及3种真菌组合试验。结果表明:(1)土沉香树体POD和SOD活性和MDA含量呈先升高后降低趋势,CAT活性在诱导后1天最高,随后呈下降趋势;(2)无机盐与真菌处理下土沉香的抗逆能力大于激素与真菌处理,其中无机盐与真菌组合试验的处理4(1.0%CaCl2+0.5%FeSO4+2.0%NaCl+黑绿木霉∶腐皮镰孢∶龙眼焦腐(1∶1∶1))和激素与真菌组合试验的处理2(0.01%茉莉酸甲酯+0.1%乙烯利+0.2%水杨酸钠+黑绿木霉∶腐皮镰孢∶龙眼焦腐(1∶1∶1))分别为同类处理最高;(3)土沉香抗逆能力高低与木芯变色长度存在显著正相关性;(4)理论上,土沉香抗逆能力最强诱导组合分别为0.93%CaCl2+0.53%FeSO4+2.5%NaCl+黑绿木霉∶腐皮镰孢∶龙眼焦腐(1∶1∶1)和0.005%茉莉酸甲酯+0.006%乙烯利+0.2%水杨酸钠+黑绿木霉∶腐皮镰孢∶龙眼焦腐(1∶1∶1)。  相似文献   
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