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1.
龙牙百合的植株再生与遗传转化 总被引:19,自引:0,他引:19
以龙牙百合鳞片叶切块为外植体,通过多种培养基的比较试验,得出MS 2,4-D 2mg/L 6-BA 0.2mg/L是诱导愈伤的最佳培养基,MS 6-BA 1mg/L NAA 0.05mg/L是不定芽诱导及伸长的适宜培养基。MS N_AA2mg/L是生根的最佳培养基。本试验已建立了适用于龙牙百合遗传转化的快速高频再生系统。用携带有几丁质酶基因和β—1、3葡聚糖酶基因的工程菌,通过农杆菌介导法和基因枪转化法转化龙牙百合,经PCR和点杂交检测证明外源基因已经整合到植物染色体中。同时对农杆菌介导法和基因枪法进行比较,发现农杆菌介导法的转化率为16.7%,基因枪法的转化率为50%,因此可能基因枪转化法更适于龙牙百合的遗传转化。 相似文献
2.
Maize gluten (a byproduct from the starch industry) was used at four different levels (5, 10, 15 and 20% w/w) replacing the
fish meal, a component of supplementary diet, under a semi-intensive culture system. The impact of different diets on the
physico-chemical parameters of water, growth and flesh quality of catla, Catla catla; rohu, Labeo rohita; and mrigal, Cirrhina mrigala was studied. Growth in terms of body weight gain was highest when fed a diet having 5% maize gluten (replacing fish meal
at 25% level) for all the fish species. However, incorporation of maize gluten at higher levels led to decline in growth,
since maize gluten is deficient in essential amino acids like methionine, lysine and threonine, etc. The flesh quality in
terms of total protein, total lipid, total sugar, moisture and total ash was also determined at the termination of the experiment
to see whether there was any significant variation with the incorporation of maize gluten or not. 相似文献
3.
4.
M.?AshrafEmail author T.?Mahmood F.?Azam R.?M.?Qureshi 《Biology and Fertility of Soils》2004,40(2):147-152
The beneficial role of green manures in rice production is generally ascribed to their potential of supplying plant nutrients, particularly nitrogen (N). However, the mechanisms through which green manures enhance the crop productivity are poorly understood. Pot experiments were conducted using a 15N-tracer technique: (1) to compare the biomass production potential of sesbania (Sesbania aculeata Pers.) and maize (Zea mays L.) as green manuring crops for lowland rice and (2) to compare the effect of the two types of green manure and inorganic N on the dry matter accumulation and N uptake by two rice (Oryza sativa L.) cultivars, viz. IR-6 and Bas-370. Although maize produced three times higher shoot biomass compared with sesbania, the latter showed higher N concentration; and thus the total N yield was similar in the two types of plants. Applying the shoot material of the two plants to flooded rice significantly enhanced the dry matter yield and N uptake by the two rice cultivars, the positive effects generally being more pronounced with sesbania than with maize amendment. The difference in the growth-promoting potential of the two plant residues was related more to an increased uptake of the native soil N rather than to their direct role as a source of plant-available N. A positive added nitrogen interaction (ANI) was observed due to both plant residues, the effect was much more pronounced with the application of sesbania than with maize residues. In both rice cultivars, inorganic N also caused a substantial ANI, particularly at higher application rate. Losses from the applied N were 2–3 times lower from sesbania, compared with maize treatment. Green manuring with sesbania also caused much lower N losses than the inorganic N applied at equivalent or higher rates. The overall benefit of green manuring to rice plants was higher than inorganic N applied at comparable rates. The two rice cultivars differed in their response to green manuring, IR-6 generally being more responsive than Bas-370. 相似文献
5.
Mathias?FosuEmail author Ronald?F.?Kühne Paul?L.?G.?Vlek 《Biology and Fertility of Soils》2003,39(2):117-122
In order to understand the efficiency of residue-N use and to estimate the minimum input required to obtain a reasonable level of crop response, it is important to quantify the fate of the applied organic-N. The recovery of N from 15N-labelled Crotalaria juncea was followed in the soil and the succeeding maize crop. Apparent N recovery (ANR) by maize from unlabelled Crotalaria juncea, Crotalaria retusa, Calopogonium mucunoides, Mucuna pruriens and mineral fertilizer at three locations were also evaluated. The maize crop recovered 4.7% and 7.3% of the 15N-labelled C. juncea-N at 42 days after sowing (DAS) and at final harvest, respectively. The corresponding 15N recovery from the soil was 92.4% and 58.5%. The highest mean ANR of 57.4% was with mineral fertilizer, whereas the mean ANR of 14.3% from C. retusa was the lowest. A large pool substitution and added-N interaction effect was observed when comparing N recovery from the labelled and unlabelled C. juncea. The amount of residue-N accounted for by the isotope dilution method at 42 DAS was 97.1% and at final harvest 65.8%. The large residue-N recovery in the soil organic-N pool explains the residual effect usually observed with organic residue application. 相似文献
6.
Ying?Liu Shi-jie?HanEmail author Xue-feng?Li Yu-mei?Zhou Jun-hui?Zhang Xia?Jia 《林业研究》2004,15(3):187-191
The impacts of elevated atmospheric CO2 concentrations (500 μmol·mol−1 and 700 μmol·mol−1) on total soil respiration and the contribution of root respiration ofPinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese
Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration ofPinus koraiensis seedlings were measured by a Li-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil instantaneously to terminate the
supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration.
Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively.
The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on
June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature
between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There
was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 μmol·m−2·s−1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively.
Foundation item: This study was supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX1-SW-01) and the National
Natural Science Foundation of China (30070158).
Biography: LIU Ying (1976-), female, Ph. D. Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China.
Responsible editor: Song Funan 相似文献
7.
Filipe?Selau?CarlosEmail author Bruno?Loss?dos?Santos Robson?Andreazza Marino?José?Tedesco Lawrence?Morris Flávio?Anastácio?de?Oliveira Camargo 《Paddy and Water Environment》2017,15(1):133-144
Treated industrial effluents have high levels of nutrients and dissolved organic matter. The irrigation of rice by flooding can increase nutrient uptake and grain yield. Therefore, this study evaluated the nutrient contents in the shoots and grain of the rice crop and also the chemical of the soil after irrigation of the crop with leachate of the treated industrial effluent. A greenhouse experiment was conducted using pots filled with 20 kg of soil in a randomized block design with three replications. The treatments consisted of control (irrigation with distilled water) and four concentrations of the leachate (25, 50, 75, and 100 %) for irrigation. At the end of the experiment, the nutrient contents in tissues of rice plants, sterility of spikelets, and grain mass were evaluated. Results showed that irrigation with the leachate at 25 % content increased the macro- and micronutrients’ concentrations in the shoot biomass and grain, except for potassium and iron. Irrigation with the industrial leachate decreased tillering and grain yield; however, it increased chlorophyll content, sterility of spikelets, and sodium intake at this leachate concentration. The potassium and sodium levels and the electrical conductivity values of soils irrigated with treated industrial leachate were increased. The use of the treated leachate from industrial effluents is an alternative that reuses the nutritional load, but the volume of leachate should be limited and monitored to prevent the sodicity in the soil and problemsdue to eutrophication. 相似文献
8.
9.
Boniface?D.?KashinaEmail author Robert?B.?Mabagala Anatolia?A.?Mpunami 《Phytoparasitica》2003,31(2):188-199
An investigation of the biological properties of the virus causing tomato yellow leaf curl disease in Tanzania was initiated
to compare it with other known tomato yellow leaf curl viruses. Properties relating to acquisition and inoculation feeding
time, persistence, mechanical inoculation, seed transmission and host range were studied. Results obtained indicate that the
virus was transmitted persistently byBemisia tabaci Genn., but it was not mechanically, sap- or seed-transmissible. Minimum acquisition and inoculation feeding time was 30 min.Capsicum annuum, Datura stramonium, Nicotiana glutinosa, N. tabacum andLycopersicon esculentum were found to be hosts of the virus among the plant species tested, whereasPhaseolus vulgaris was not. It is concluded that the properties of the agent causing yellow leaf curl symptoms in tomato plants from different
regions in Tanzania are similar to those ofTomato yellow leaf curl Sardinia virus species studied elsewhere.
http://www.phytoparasitica.org posting Feb. 20, 2003. 相似文献
10.
?eljko?Tomanovi? Nickolas?G.?KavallieratosEmail author Christos?G.?Athanassiou Olivera?Petrovi? 《Phytoparasitica》2003,31(1):19-26
A new hymenopteran aphid parasitoid species (Praon uroleucon sp. n.) fromUroleucon sp. infestingCarduus acanthoides L. is described from Yugoslavia. It is diagnosed and illustrated with scanning electron microscope photographs and line drawings.
The new species is placed in thePraon dorsale species group, and a key to species of that group is provided.
http://www.phytoparasitica.org posting Dec. 9, 2002. 相似文献