摘要:

Own rooted Concord grapevines,Vitis labruscanaB, planted in 1981, trained to the Geneva Double Curtain training system, were used to investigate their response of levels of total arginine of different vine organ to high rates of soil nitrogen fertilization and the growth regulator daminozide.

ISSN:0190-4167    

DOI:10.1080/01904169009364169

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The effect of aluminum (Al) ions on the germination of wheat(Triticum aestivumL.) seeds has been investigated using two varieties, one sensitive to Al (Robin) and the other relatively Al‐tolerant (Carazinho). High concentrations of Al (i.e. greater than 1 mM) were required to inhibit the growth of the emerging roots and shoots of germinating seeds of both varieties. Moreover, Al at concentrations up to 10 mM did not affect the mobilization of carbohydrate reserves in the germinating seeds. It was concluded that germinating seeds of both wheat varieties were much less sensitive to the effects of Al than were established seedlings.

ISSN:0190-4167    

DOI:10.1080/01904169009364170

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169009364171

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Tumorous crown gall tissue induced on the stems of sunflower(Helianthus annusL. cv. Mammoth Russian) plants by the soil bacteriumAgrobacterium tumefaciensstrongly reduced Fe3+to Fe2+as evidenced by the formation of Fe2+BPDS complex compared to surrounding “normal” stem tissue. Tumorous tissue contained significantly more Fe, Cu, K, and P, and less Zn and Mg than the nontumorous stem tissue. The reducing environment of the tumorous tissue appears to affect the general nutrition and growth of this tissue.

ISSN:0190-4167    

DOI:10.1080/01904169009364172

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Although large quantities of nitrogen are required for high soybean [Glycine max(L.) Merr.] yields, yield increases with N fertilization are not easily achieved. Along with adverse effects on N‐fixation, N fertilization has been reported to stimulate excessive vegetative growth, especially in soybeans with the indeterminate growth habit. The objective of this study was to compare the influence of N application (150 kg N/ha, applied in irrigation water between growth stages Rl and R5) on morphological development of the indeterminate cultivar Weber and the semi‐dwarf determinate line 172–16. The two genotypes were morphologically similar at growth stage Rl (beginning bloom), but morphological differences were apparent from R3 (beginning pod stage) until maturity, with greater development of main‐stem and: branch lengths for Weber than for 172–16.’ For Weber, N fertilization greatly stimulated branch length; this was apparent at growth stage R3 and was associated with lodging and disease infestation. For the lodging‐resistant 172–16, which had essentially achieved final node numbers by R3, N had little effect on branching or main‐stem development. For Weber, substantial yield decreases have been associated with high inputs of N, whereas yields of 172–16 may be more stable or even enhanced as N availability increases. These results may be related to the differential influence of N on vegetative growth responses of these genotypes.

ISSN:0190-4167    

DOI:10.1080/01904169009364173

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The effect of ammonium nitrate fertilization on ureide synthesis, xylem transport and assimilation was examined in four week old nodulated soybean plants. In nodules the activity of 5‐phosphoribosylpyrophosphate amidotransferase, a key enzyme of ureide biosynthesis, declined 75%, while enzymes of purine oxidation (xanthine dehydrogenase and uricase) showed no response to nitrogen treatment. Xylem sap concentrations of allantoin and allantoate, as compared to untreated controls, were reduced by about 85% and 65%, respectively. Despite the substantial decline in ureide synthesis and transport, allantoate concentration in leaves of ammonium nitrate treated plants increased by about three‐fold. No ureide accumulation was observed in leaf tissue following a suppression of ureide formation in nodules by allopurinol, an inhibitor of xanthine dehydrogenase. In the pathway of ureide assimilation in leaves, application of inorganic nitrogen had no effect on activity of allantoinase, but caused a 50% drop in activity of allantoate amidohydrolase. Therefore, the observed accumulation of allantoate in soybean leaves in response to nitrogen fertilization was due to new ureide synthesis in plant tissues other than nodules, or to retardation of ureide degradation in leaves caused by the alternative source of nitrogen.

ISSN:0190-4167    

DOI:10.1080/01904169009364174

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Boron fertilization and inoculation withPisolithus tinctorius(Pers.) Coker and Couch increased foliar and total seedling nutrient content of boron, calcium, copper, iron, potassium, magnesium, manganese and phosphorus in shortleaf pine seedlings (Pinus echinataMill.). Noninoculated seedlings fertilized with boron showed no increase in nutrient content other than B. The increase in nutrient content of inoculated seedlings fertilized with boron was correlated with increased mycorrhizal infection. Boron fertilization may affect indirectly the mineral nutrition of tree seedlings by increasing mycorrhizal fungi colonization of their roots.

ISSN:0190-4167    

DOI:10.1080/01904169009364175

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Chickpea plants (Cicer arietinumL cv. ILC 195) were grown for 24 days in water culture under two regimes of nitrogen nutrition (NO3or NH4‐N) with or without Fe. For plants fed with NO3‐N, Fe stress severely depressed fresh weight accumulation and chlorotic symptoms of Fe‐deficiency developed rapidly. Little difference in growth occurred in the NH4‐fed plants, whether or not Fe was withheld, with no visual evidence of Fe‐deficiency indicating a beneficial effect of NH4in depressing the symptoms of Fe chlorosis. Typical pH changes were measured in the nutrient solution of the control plants in relation to nitrogen supply, increasing with NO3and decreasing with NH4‐nutrition. With both forms of nitrogen, plants acidified the nutrient solution in response to Fe‐stress. Under NH4‐nutrition, acidification was enhanced by withholding Fe. In the NO3‐fed plants the uptake of all nutrients was reduced by the stress but proportionally NO3‐ and K+were most affected. Total anion uptake was depressed more than that of cation uptake. For the NH4‐fed plants withholding Fe resulted in an increased uptake of all ions except NH4+which was depressed. Regardless of the form of N‐supply, when Fe was withheld from the nutrient solution the net H+efflux calculated from the (C‐A) uptake values was closely balanced by the OH” added to the nutrient solution to compensate for the pH changes. Evidence of accumulation of organic acids in the Fe‐stressed plants was found, especially in the NO3‐fed plants, indicating a role for these internally produced anion charges in balancing cation charge in relation to the depression of NO3‐uptake associated with Fe‐stress.

ISSN:0190-4167    

DOI:10.1080/01904169009364176

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Chickpea plants(Cicer arietinumL cv. ILC 195) were grown for 24 days in water culture with NO3or NH4‐N, with or without P. The lack of P in the nutrient medium depressed total plant fresh and dry weight yields but did not induce visual symptoms of P deficiency in the shoots despite the low P concentrations found in the plant tissues. For both N‐forms, P stress decreased shoot dry weights. The effect of the stress on the root systems varied with the N‐source. For NO3‐fed plants, roots of stressed plants were longer and slightly greater in weight than those of unstressed plants but for plants supplied with NH4‐N, root weight was depressed by the lack of P. With both forms of N, P stress decreased the shoot:root ratio. For the unstressed plants the forms of N‐nutrition induced typical changes in the nutrient solution but when NO3‐fed plants were deprived of P, the nutrient medium became more acid. The response of the NO3‐fed P‐stressed plants to acidify the nutrient medium was slow. Phosphorus stress decreased the total uptake of all ions. For NO3‐fed plants the uptake of Mg was less affected by the stress and, in contrast to K and Ca, was increased in relation to the depression in growth. P stress depressed the uptake of anions more than cations and NO3‐ uptake was most affected. For NH4‐fed plants, P stress decreased the uptake of anions more than cations. Of the major cations, K and Ca were particularly depressed but Mg was less affected. The uptake of NH4was slightly enhanced in relation to the reduction in growth, indicating that N was not the limiting factor for plant growth. With both forms of N there was evidence of a greater accumulation of organic anions in the roots and sap of P deficient plants.

ISSN:0190-4167    

DOI:10.1080/01904169009364177

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169009364168

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor