摘要:

Rice seedlings(Oryza sativacv. Te Qin No. 1) were hydroponically grown in Espino's solution containing various levels of paclobutrazol introduced into the solution at the three‐leaf stage. After the 15th day of treatment, several mineral elements were determined to evaluate the effect of paclobutazol on mineral uptake.

ISSN:0190-4167    

DOI:10.1080/01904169109364179

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Dicotyledonous plants had significantly higher Mn and Fe intake rates on a near neutral soil, had a significantly higher Mn intake rate on a slightly calcareous soil, but had lower Mn and Fe intake rates on a calcareous soil, than monocotyledonous plants. This dependency on soil reaction suggests that dicots utilize primarily a chemical reduction mechanism, whereas monocots utilize some less pH‐dependent mechanism (possibly Mn(III)‐, Fe(III)‐organic complexation) to mobilize soil Mn and Fe. Soluble soil Mn and Fe fractions in the rhizosphere were consistently positively correlated with each other, as were Mn and Fe intake rates. These results suggest that for soil‐grown plants, Mn and Fe uptake was positively interrelated because both Mn and Fe were mobilized by similar root processes.

ISSN:0190-4167    

DOI:10.1080/01904169109364180

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Increased above‐ground dry matter and grain yields were found for two hydroponically grown maize hybrids (Pioneer‐3925 and Pioneer‐3949) when plants were supplied with an NH4+‐enhanced nutrient solution (31 percent of total N) compared with a control (4 percent of total N as NH4+). The major difference in yield developed between silking and 2 weeks post‐silking and silking and 4 weeks post‐silking for the P‐3925 and P‐3949 respectively. The reduced nitrogen content of the stover (leaves plus stalk) was consistently higher on the NH4+‐enhanced nutrient solution. The decreased production of the control treatment may have resulted from a reduced photsynthetic capacity.

ISSN:0190-4167    

DOI:10.1080/01904169109364181

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Iron‐efficient Coker 227 oat responds to Fe‐deficiency stress by producing a phytosiderophore that solubilizes Fe while Fe‐inefficient TAM 0–312 does not. WF9 and ys1corn are also Fe efficient and inefficient, respectively, but neither produce much phytosiderophore during Fe‐deficiency stress. The objective of this study was to determine if phytosiderophore released by Fe‐deficiency stressed Coker 227 oat would increase the availability of Fe to TAM 0–312 oat, WF9 corn, or ys1corn. These cultivars were grown in a modified Steinberg solution with 1.2 mg/L Fe and in ratios of (Coker:TAM) 28:0, 21:7, 14:14, 7:21, and 0:28 and (Coker:corn) of 28:0, 21:1, 14:2, 7:3 and 0:4. Daily chlorosis ratings and periodic measurements of leaf and root Fe contents and phytosiderophore release were determined. Iron solubilized by the phytosiderophore released by Fe‐stressed Coker 227 oat made Fe available to WF9 corn at the 21:1 and 14:2 Coker:WF9 ratios as reflected in chlorosis ratings and leaf Fe contents, but ys1. was incapable of obtaining Fe at any of the ratios. TAM 0–312 oat was less efficient in obtaining Fe from Fe‐phytosiderophore than was WF9 corn. As the ratio of Coker:WF9 and Coker:TAM decreased, Coker 227 oat either became more cholorotic and/or leaf Fe declined, but this did not occur with Coker 227 growing with yS1corn. Thus, ability to absorb Fe from Fe‐phytosiderophore released by Fe‐stressed Coker 227 oat was in the order WF9 corn > TAM 0–312 oat > ys1corn.

ISSN:0190-4167    

DOI:10.1080/01904169109364182

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The effect of polyethylene glycol (PEG) 4000 on sour orange (SO) and Cleopatra mandarin (CM) rootstock seedlings grown in fine sand under greenhouse conditions was studied. The PEG treatments were initiated by adding PEG to half strength Hoagland's solution to achieve final osmotic potentials of ‐0.10, ‐0.20, and ‐0.35 MPa. The no PEG control treatment had an osmotic potential of ‐0.05 MPa. Seedlings were harvested 6 months after starting PEG treatments.

ISSN:0190-4167    

DOI:10.1080/01904169109364183

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Precipitation of Al(OH)3and aluminum phosphate may occur in nutrient solution if a large amount of Al and P have been added to a relatively high pH. The objective of this study was to develop and test a supernatant‐solution method for Al phytotoxicity studies with large and/or old plant seedlings. Effects of pH and additions of Al and P on ionic strength and concentrations of Al and P in supernatant nutrient solutions were investigated. Two sets of supernatant nutrient solutions at two pH levels were prepared. The pH 4.0 set and 4.5 set contained seven levels of Al (maximum Al concentration of 6355 and 378 μM) and similar P concentration about 32 and 6 μM P, respectively. The Al concentrations in supernatant solutions were dependent on preparation procedure. The pH 4.0 set was tested in the greenhouse study with 6‐month‐old citrus seedlings and found to be successful as culture solutions for Al phytotoxicity studies. These two sets are suitable for growth of large (about 0.3 m) and/or old (about 6 mon.) seedlings. This supernatant‐solution method makes it possible to study Al phytotoxicity of large and/or old seedlings, to avoid the confounding effects of P on Al with respect to plant growth, and to report the actual concentrations of Al and P in growth solutions.

ISSN:0190-4167    

DOI:10.1080/01904169109364184

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169109364185

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169109364186

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169109364178

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor