XYLEM-TO-PHLOEM TRANSFER OF ORGANIC NITROGEN IN YOUNG SOYBEAN PLANTS

被引:32
作者
DASILVA, MC [1 ]
SHELP, BJ [1 ]
机构
[1] UNIV GUELPH,DEPT HORT SCI,GUELPH N1G 2W1,ONTARIO,CANADA
关键词
D O I
10.1104/pp.92.3.797
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Xylem-to-phloem transfer in young vegetative soybean (Glycine max [L.] Merr.) plants (V4 stage) was identified as the difference in the distribution of [14C]inulin, a xylem marker, and [14C]aminoisobutyric acid (AIB), a synthetic amino acid, fed via the transpiration stream. Since [14C]AIB was retained in the stem to some extent, whereas [14C]inulin was not, the distribution of these marker compounds in each leaf was expressed as a percentage of the total [14C] radioactivity recovered in the foliage. The developing third trifoliolate was a consistent and reliable indicator of xylem-to-phloem transfer. The phloem stream provided to the developing trifoliolate up to fourfold the relative proportion of solute received from the xylem stream; this was markedly reduced by increased light intensity and consequently water flow through the xylem. Evidence from heat girdling experiments is discussed with respect to the vascular anatomy of the soybean plant, and interpreted to suggest that direct xylem-to-phloem transfer in the stem, in the region of the second node, accounted for about one-half of the AIB supplied to the developing trifoliolate, with the remainder being provided from the second trifoliolate. Since AIB is not metabolized it seems likely that rapid transfer within the second trifoliolate occurred as direct veinal transfer rather than indirect cycling through the mesophyll. This study confirmed that xylem-to-phloem transfer plays a major role in the partitioning of nitrogen for early leaf development.
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页码:797 / 801
页数:5
相关论文
共 15 条
[1]  
BELL WILLIS H., 1934, BOT GAZ, V95, P622, DOI 10.1086/334433
[2]  
CARLSON JB, 1973, SOYBEANS IMPROVEMENT, P17
[3]  
DASILVA MC, 1989, THESIS U GUELPH GULE
[4]   A HOT-WIRE TECHNIQUE FOR GIRDLING STEMS AND PETIOLES OF HERBACEOUS PLANTS [J].
DEWEY, SA ;
CHILCOTE, DO ;
APPLEBY, AP .
AGRONOMY JOURNAL, 1987, 79 (03) :587-590
[5]   STAGE OF DEVELOPMENT DESCRIPTIONS FOR SOYBEANS, GLYCINE-MAX (L) MERRILL [J].
FEHR, WR ;
CAVINESS, CE ;
BURMOOD, DT ;
PENNINGTON, JS .
CROP SCIENCE, 1971, 11 (06) :929-+
[6]   SHORT-TERM RESPONSES OF PHLOEM TRANSPORT TO MECHANICAL PERTURBATION [J].
JAEGER, CH ;
GOESCHL, JD ;
MAGNUSON, CE ;
FARES, Y ;
STRAIN, BR .
PHYSIOLOGIA PLANTARUM, 1988, 72 (03) :588-594
[7]   INTERNODES OF GRAIN LEGUMES - NEW LOCATION FOR XYLEM PARENCHYMA TRANSFER CELLS [J].
KUO, J ;
PATE, JS ;
RAINBIRD, RM ;
ATKINS, CA .
PROTOPLASMA, 1980, 104 (1-2) :181-185
[8]   PARTITIONING OF CARBON AND NITROGEN AND THE NUTRITION OF ROOT AND SHOOT APEX IN A NODULATED LEGUME [J].
LAYZELL, DB ;
PATE, JS ;
ATKINS, CA ;
CANVIN, DT .
PLANT PHYSIOLOGY, 1981, 67 (01) :30-36
[9]   EFFECT OF TRANSLOCATION-HINDERING PROCEDURES ON SOURCE LEAF PHOTOSYNTHESIS IN CUCUMBER [J].
MAYORAL, ML ;
PLAUT, Z ;
REINHOLD, L .
PLANT PHYSIOLOGY, 1985, 77 (03) :712-717
[10]   UPTAKE AND UTILIZATION OF XYLEM-BORNE AMINO-COMPOUNDS BY SHOOT ORGANS OF A LEGUME [J].
MCNEIL, DL ;
ATKINS, CA ;
PATE, JS .
PLANT PHYSIOLOGY, 1979, 63 (06) :1076-1081