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921.
922.
923.
野葛叶片和茎段高频再生体系的建立 总被引:5,自引:3,他引:2
探讨几种因子对野葛叶片和茎段高频再生体系建立的影响。采用植物组织培养、正交实验和单因子实验的方法。野葛叶片和茎段的最佳消毒方式为70%酒精处理30 s后再用0.1%HgCl2处理15 min;野葛叶片愈伤组织诱导的最佳培养基为MS+NAA 1.0 mg·L-1+2,4-D 2 mg·L-1,野葛茎段愈伤组织诱导的最佳培养基为MS+NAA 0.5 mg·L-1+6-BA 1.0 mg·L-1+2,4-D 2 mg·L-1;暗培养更有利于野葛愈伤组织的诱导;野葛叶片和茎段愈伤组织诱导的最佳蔗糖浓度均为30 g·L-1;野葛叶片愈伤组织的最佳出芽培养基为MS+NAA 1.0 mg·L-1+6-BA 3.0 mg·L-1,而野葛茎段愈伤组织的最佳出芽培养基为MS+ NAA 0.5 mg·L-1+KT 2 mg·L-1;光照培养更有利于野葛叶片和茎段愈伤组织芽的再分化;野葛叶片愈伤组织再生芽生根的最佳培养基为MS+NAA 0.5 mg·L-1+PP333 0.5 mg·L-1,而野葛茎段愈伤组织再生芽生根的最佳培养基为MS+NAA 0.5 mg·L-1+PP333 3.0 mg·L-1;野葛叶片和茎段愈伤组织再生芽生根的最佳蔗糖浓度均为30 g·L-1;叶片再生苗移栽的最佳PP333浓度为1.0 mg·L-1,茎段再生苗移栽的最佳PP333浓度为3.0 mg·L-1;叶片和茎段再生苗的最佳移栽基质均为蛭石:珍珠岩(2:1)。 相似文献
924.
The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton lines (GK12 and GK19) and their pa-rental non-Bt cotton line (Simian3) associated with searching and feeding behaviors of cotton aphids on leaves or leaf extracts of cotton plants. EPG results showed that there were some differences among behaviors of cotton aphids on 2 Bt cotton and 1 non-Bt cotton lines. Cotton aphids performed similarly to leaf surface extracts from 3 cotton lines; and leaf surface chemicals, mainly volatiles and waxes, were almost identical in the components and concentrations among the cotton lines. However, three cotton lines were quite different from each other in the densities of certain kinds of covering trichomes. Therefore, the relationships between the physical characteristics and the searching behaviors of cotton aphids on the three cotton lines were constructed as the regression equations. Glandular trichomes and covering trichomes with 5 branches influenced the cotton aphids' searching behaviors effectively; and other trichomes with other branches affected aphids in varying ways. These results demonstrated that leaf surface physical factors of transgenic Bt cotton lines different from their parental non-Bt line could affect the penetration behaviors of non-target cotton aphids. Cotton aphids penetrate and feed more easily on two Bt cotton lines than on the non-Bt cotton line. 相似文献
925.
Highly polymorphic microsatellite loci in the rice- and maize-infecting fungal pathogen Rhizoctonia solani anastomosis group 1 IA 总被引:1,自引:0,他引:1
Zala M McDonald BA DE Assis JB Ciampi MB Storari M Peyer P Ceresini PC 《Molecular ecology resources》2008,8(3):686-689
Ten polymorphic microsatellite loci were isolated and characterized from the rice- and maize-infecting Basidiomycete fungus Rhizoctonia solani anastomosis group AG-1 IA. All loci were polymorphic in two populations from Louisiana in USA and Venezuela. The total number of alleles per locus ranged from four to eight. All 10 loci were also useful for genotyping soybean-infecting R. solani AG-1 isolates from Brazil and USA. One locus, TC06, amplified across two other AG groups representing different species, showing species-specific repeat length polymorphism. This marker suite will be used to determine the global population structure of this important pathogenic fungus. 相似文献
926.
Elizabeth J. White Mauritz Venter Dr. Nicholas F. Hiten Johan T. Burger 《Biotechnology journal》2008,3(11):1424-1428
A wide range of plant RNA extraction methods are available; however, many of these are limited in their application for a diverse range of plant species. With special emphasis on robustness and versatility, we have improved the cetyltrimethylammonium bromide (CTAB) method and isolated high-quality RNA from 16 different plant species. The major modifications made to the protocol described here were a reduction of sample treatment steps and an increase in β-mercaptoethanol concentration (to 3%) resulting in a robust, rapid and reproducible plant RNA extraction protocol that can be used for a broad range of plant species and tissue types. 相似文献
927.
928.
R. A. Richer 《African Journal of Ecology》2008,46(4):556-564
Whole tree manipulation experiments were performed in the common southern African tree species, Brachystegia spiciformis to test a novel hypothesis that decreasing Total nonstructural carbohydrates (TNC) in the stem could cause bud break in Brachystegia spiciformis. The experimental treatments included fertilization, canopy defoliation, shading and stem heating to decrease stem carbohydrates. None of the treatments significantly decreased mean stem TNC. Likewise the heating, fertilization and defoliation treatments did not significantly affect the date of bud break. However, shading significantly delayed bud break. This delay in bud break could not be attributed to changes in leaf level photosynthetic traits, stem water content, leaf predawn water potential or delayed leaf fall. These results question widely accepted hypotheses about the mechanisms controlling bud break and suggest a carbohydrate homeostatic mechanism. 相似文献
929.
Short-term responses of leaf growth rate to water deficit scale up to whole-plant and crop levels: an integrated modelling approach in maize 总被引:1,自引:0,他引:1
Chenu K Chapman SC Hammer GL McLean G Salah HB Tardieu F 《Plant, cell & environment》2008,31(3):378-391
Physiological and genetic studies of leaf growth often focus on short-term responses, leaving a gap to whole-plant models that predict biomass accumulation, transpiration and yield at crop scale. To bridge this gap, we developed a model that combines an existing model of leaf 6 expansion in response to short-term environmental variations with a model coordinating the development of all leaves of a plant. The latter was based on: (1) rates of leaf initiation, appearance and end of elongation measured in field experiments; and (2) the hypothesis of an independence of the growth between leaves. The resulting whole-plant leaf model was integrated into the generic crop model APSIM which provided dynamic feedback of environmental conditions to the leaf model and allowed simulation of crop growth at canopy level. The model was tested in 12 field situations with contrasting temperature, evaporative demand and soil water status. In observed and simulated data, high evaporative demand reduced leaf area at the whole-plant level, and short water deficits affected only leaves developing during the stress, either visible or still hidden in the whorl. The model adequately simulated whole-plant profiles of leaf area with a single set of parameters that applied to the same hybrid in all experiments. It was also suitable to predict biomass accumulation and yield of a similar hybrid grown in different conditions. This model extends to field conditions existing knowledge of the environmental controls of leaf elongation, and can be used to simulate how their genetic controls flow through to yield. 相似文献
930.
Overmyer K Kollist H Tuominen H Betz C Langebartels C Wingsle G Kangasjärvi S Brader G Mullineaux P Kangasjärvi J 《Plant, cell & environment》2008,31(9):1237-1249
Genetically tractable model plants offer the possibility of defining the plant O3 response at the molecular level. To this end, we have isolated a collection of ozone (O3 )-sensitive mutants of Arabidopsis thaliana . Mutant phenotypes and genetics were characterized. Additionally, parameters associated with O3 sensitivity were analysed, including stomatal conductance, sensitivity to and accumulation of reactive oxygen species, antioxidants, stress gene-expression and the accumulation of stress hormones. Each mutant has a unique phenotypic profile, with O3 sensitivity caused by a unique set of alterations in these systems. O3 sensitivity in these mutants is not caused by gross deficiencies in the antioxidant pathways tested here. The rcd3 mutant exhibits misregulated stomata. All mutants exhibited changes in stress hormones consistent with the known hormonal roles in defence and cell death regulation. One mutant, dubbed re-8 , is an allele of the classic leaf development mutant reticulata and exhibits phenotypes dependent on light conditions. This study shows that O3 sensitivity can be determined by deficiencies in multiple interacting plant systems and provides genetic evidence linking these systems. 相似文献