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101.
Effect of Ca on composition of fat body of peanut seed 总被引:1,自引:0,他引:1
Peanut fruits were grown in nutrient media with or without Ca and in a soil with two Ca levels, from the 20th day after penetration
of the gynophore. Seed weight was smaller in the nutrient medium without Ca than in the nutrient medium with Ca, and it was
also smaller in the soil with 4 meq of exchangeable Ca (L treatment) than in the soil with 10 meq of exchangeable Ca (H treatment).
The fat body of seeds from the Ca deficient medium and the L treatment had a decreased phospholipid content and an increased
simple lipid content. In the seed from the H treatment, phosphatidylcholine increased from the 30th to 60th day, while caldiolipin
decreased. The amount of triglyceride in the simple lipid content of fat body was decreased by Ca deficiency in the nutrient
medium, whereas that of diglyceride was increased, but these effects were not observed in the fat body of the seed from the
L treatment. No effect of Ca deficiency was observed in the fatty acid composition of triglyceride. 相似文献
102.
Soaking the seeds of mungbean (Vigna radiata L. Wilczek cv. K-851) in pyridoxine solution significantly enhanced leaf N, P and K concentrations at different growth stages,
and seed protein concentration at harvest. Leaf N, P and K were significantly correlated with root length and seed protein.
Thus, pyridoxine application not only enhanced the availability of nutrients to plants but also was responsible for the maintenance
of a favourable source-sink relationship, thus ensuring more nutritious seeds of mungbean. 相似文献
103.
The effect of phosphorus (P) concentration in barley seed on seedling growth has not been much investigated. Consequently,
two experiments were conducted in the greenhouse to determine the effect of P concentration in barley seed (Hordeum vulgare L., cv. Empress) on the seedlings grown in sand-filled boxes receiving a culture solution without P. Seeds were selected
with three P concentrations: high-P (113.0 mmol P kg−1), medium-P (80.7 mmol P kg−1) and low-P (54.9 mmol P kg−1). At 21 days after sowing, the shoot and root yield or shoot height was the least with seedlings from low-P seed. In the
other experiment, high-P and low-P seeds were wetted with distilled water or with a solution of 25.8 cmol L−1 of NaH2PO4 for 24 h, and then grown for 31 days. Solution P had been imbibed by seeds whether low or high in native P, but only the
imbibed P held by low native P seed benefited seedling dry matter accumulation and shoot elongation. The lack of benefit from
seed-imbibed P on seedlings grown from high-P barley seed was associated with low recovery of the imbibed P in those seedlings. 相似文献
104.
Ian A. Graham Laura M. Smith Christopher J. Leaver Steven M. Smith 《Plant molecular biology》1990,15(4):539-549
The cucumber malate synthase (MS) gene, including 1856 bp of 5 non-trnascribed sequence, has been transferred into Petunia (Mitchell) and Nicotiana plumbaginifolia plants using an Agrobacterium binary vector. The transferred gene is found in variable copy number in different transformants, and is stably transmitted in each case as a single Mendelian character. Transgene mRNA accumulates in the seedling during the first three days of germination, then declines in amount as the cotyledons emerge from the seed. The decline is more pronounced in light-grown seedlings than in dark-grown seedlings. Expression of the MS transgene is also detected at a low level in petals of transformed Petunia plants. In these respects the pattern of MS gene expression is similar in cucumber and in trnasformed plants, showing that the transferred DNA fragment contains a functional MS gene. A 1076 bp fragment of 5 sequence was linked to the -glucuronidase reporter gene and transferred into Nicotiana, where it was shown to direct temporal and spatial patterns of expression similar to that of the complete MS gene. However, histochemical localisation of -glucuronidase activity demonstrated that the chimaeric gene is expressed not only in cotyledons of transgenic plants, but also in endosperm and some hypocotyl cells during early germination. The relevance of these findings to the control of malate synthase gene expression is discussed. 相似文献
105.
K. Peng A. J. W. G. Visser A. van Hoek C. J. A. M. Wolfs J. C. Sanders M. A. Hemminga 《European biophysics journal : EBJ》1990,18(5):277-283
Fluorescent probes located in heterogeneous environments give rise to anomalous time-resolved fluorescence anisotropy. A simple analytical expression of anisotropy has been derived for the case of a small difference in local fluorescence lifetimes. The expression has the diagnostic advantage that the time dependence of the fluorescence anisotropy can be predicted from the differences in fluorescence lifetimes and residual anisotropies of the probes located in different sites. Using this model, the local fluorescence anisotropy parameters and the relative contributions of the lipid probe octadecyl rhodamine B in a lipid environment and in the vicinity of bacteriophage M13 coat protein reconstituted in phospholipid bilayers, composed of 80% 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 20% 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol have been determined experimentally. At 40°C, the correlation times for bound and free probes are 2.3 and 3.0 ns, respectively, while the corresponding order parameters are 0.85 and 0.62, respectively.Abbreviations ESR
electron spin resonance
- DMPC
1,2-dimyristoyl-sn-glycero-3-phosphocholine
- DMPC
1,2-dimyristoyl-sn-glycero-3-phosphoglycerol
- L/P ratio
phospholipid to coat protein molar ratio
- <>
average fluorescence lifetime
-
r(0)
initial anisotropy
-
r()
residual anisotropy
On leave of Shanghai Medical Equipment Research Institute, 77 Jiang Ning Rd. Shanghai, People's Republic of China
Offprint requests to: M. A. Hemminga 相似文献
106.
应用梯度离心和超速离心浓缩获得部分提纯的病毒制剂,产量约为7.45g/kg病叶提纯的病毒制剂的紫外吸收曲线呈典型的核蛋白吸收曲线,OD260/OD242和OD260/OD280的比值分别为1.24和1.38。病毒粒子呈线状,宽13—14nm,长度主要分布于250—300nm和550—700nm之间,1000nm以上的粒子也有检到。病毒外壳蛋白仅由一个分子量约为30Kd的亚基组成。在免疫电镜试验中、病毒粒子与日本WYMV抗血清发生强烈的血清学反应。新鲜病叶的超薄切片中可看到大量风轮体和膜状体。 相似文献
107.
108.
Pasteuria penetrans spore adhesion to Meloidogyne javanica second-stage juveniles (J2) was examined following several different pretreatments of the latter. The detergents sodium dodecyl sulfate and Triton X-100, the carbohydrates fucose and α-methyl-D-mannoside, and the lectins concanavalin A and wheat germ agglutinin reduced spore attachment. Spores exposed to M. javanica surface coat (SC) extract exhibited decreased adherence to the J2 surface. Second-stage juveniles that had been treated with antibodies recognizing a 250-kDa antigen of J2 SC extract had fewer spores attached to their surfaces, as compared to nontreated J2, except in the head region. This inhibition pattern was similar to that of antibody-labelling on M. javanica J2 as observed by electron microscopy. It is suggested that several SC components, such as carbohydrate residues, carbohydrate-recognition domains, and a 250-kDa antigen, are involved in P. penetrans spore attachment to the surface of M. javanica. 相似文献
109.
We compared above-ground allocation patterns in mature shrubs of Banksia hookeriana from three 13-year-old populations, growing on nutrient-impoverished sands to determine whether C (dry mass) could be a substitute for mineral nutrients (N, P, K, Ca, Mg and NA). The percentage of reproductive structures to total above-ground growth (reproductive effort; RE) was integrated over nine successive reproductive cycles. Only 0.5% of above-ground dry mass was allocated to seeds compared with 31% to total RE. Allocations of N (24%) and P (48%) to seeds, and N (44%) and P (65%) to RE were much higher. Allocations of K, Ca, Mg and Na to seeds (<1–3%), and RE (21–35%) were closer to that of dry mass. Relative allocation (RA) is defined as the proportion of a nutrient element allocated to a structure relative to its dry mass. RA of P to seeds was 91 and N was 44, but for K, Ca, Mg and Na ranged from only 6 for K to<1 for Na. Thus P, and to a lesser extent N, provide a much more sensitive measure of the relative cost of reproduction than C in this nutrient-limited system. 相似文献
110.
Molecular evolution of pteridophytes and their relationship to seed plants: Evidence from complete 18S rRNA gene sequences 总被引:1,自引:0,他引:1
Complete 18S ribosomal RNA sequence data from representatives of all extant pteridophyte lineages together with RNA sequences from different seed plants were used to infer a molecular phylogeny of vascular plants that included all major land plant lineages. The molecular data indicate that lycopsids are monophyletic and are the earliest diverging group within the vascular land plants, whereasPsilotum nudum is more closely related to the seed plants than to other pteridophyte lineages. The phylogenetic trees based on maximum likelihood, parsimony and distance analyses show substantial agreement with the evolutionary relationships of land plants as interpreted from the fossil record. 相似文献