摘要:

Two experiments were conducted in nutrient solution to investigate effects of Al chelates on the growth and mineral composition of ryegrass. Results indicated that plants were more tolerant of Al‐citrate and Al‐NTA and accumulated Al from these chelates. Aluminum treatments resulted in decreased P and increased K concentrations in the leafy portion of the plants. Magnesium concentration was not affected whereas Ca was reduced slightly.

ISSN:0190-4167    

DOI:10.1080/01904168809363790

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904168809363791

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Annual vinca (Catharanthus roseus(L.) G. Don ‘Pink Carpet'), geranium (PelargoniumxhortorumL. H. Bailey ‘Jackpot'), and marigold (Tagetes erectaL. ‘First Lady') were grown in a sphagnum peat moss and perlite medium. Plants were irrigated with solutions of different salinity by the addition of 0.0, 1.0, 2.0, 4.0, and 8.0 g/1 of a NaCl and CaCl2mixture resulting in solution electrical conductivity (EC) values of about 1.3, 3.0, 4.5, 7.9, and 13.9 ds/m, respectively. In another experiment marigold and geranium were grown in solution culture containing the same salt mixture at 0.0, 1.0, 4.0, and 8.0 g/1 with EC values of 1.4, 3.0, 7.4, and 12.5 ds/m, respectively. All species showed some salinity tolerance up to 2.0 g/1 in peat‐perlite and 1.0 g/1 in solution culture as growth reductions were below 10% and no foliar injury occurred. Foliar injury occurred on marigold and geranium, but not annual vinca, at 4.0 and 8.0 g/1 in both growing media. On a concentration basis, recently mature leaves sampled from marigold grown in peat‐perlite contained more chloride (Cl) but less sodium (Na) than geranium and annual vinca. However results of the solution culture experiment showed that, with the exception of 1.0 g/1 treatment, geranium and marigold plants absorbed the same amount of Cl and Na when content was expressed on a mg/g dry weight basis. The low Na concentration in marigold leaves was a reflection of restricted translocation of Na from the roots to the shoots.

ISSN:0190-4167    

DOI:10.1080/01904168809363792

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Knowledge of macadamia (Macadamia integrifolia)nutrition has lagged behind problems associated with commercial production. To improve this knowledge, a 16‐kg pot experiment was conducted to study chlorosis in macadamia as induced by phosphate fertilization and soil properties. Six soils representing potential macadamia growing areas in Hawaii were used, which consisted of three volcanic ash oraalava‐derived soils (low in micronutrients and in P sorption capacity) and three highly weathered soils (high in Fe and Mn oxide contents and in P sorption). Several P levels, ranging from 0.006 to 1.6 mg P/L in soil solution, were established based on P adsorption isotherms. Macadamia was grown for 15 months; dry matter production, leaf chemical composition (P, Fe, and Mn concentration) and numerical index of leaf color were used as the growth‐response indicators.

ISSN:0190-4167    

DOI:10.1080/01904168809363793

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Four cultivars ofPhaseolus vulgarisL., Carioca, Venezuela‐ 350, Rio Tibagi and Negro Argel, were grown to maturity in a glass house with a low (1 mol m‐3) and a high (4.5 mol m‐3) potassium supply. Potassium stimulated nitrogenase activity (acetylene reduction) and the accumulation of ureides in pod walls of Carioca and Negro Argel, cultivars which had the highest rates of acetylene reduction. In three of the four cultivars the higher level of potassium nutrition resulted in a greater partitioning of above ground N to the seeds. The proportion of xylem sap N in the form of the ureides, allantoln and allantoic acid (allantoate), was only slightly increased by the higher rate of potassium supply. Seed yields were increased by high potassium in the cultivars Venezuela‐350 and Negro Argel. The results suggest that potassium stimulates the transport of nitrogenous compounds to developing fruits.

ISSN:0190-4167    

DOI:10.1080/01904168809363794

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Genotypes of white clover were grown in pots of soil in a glasshouse at a range of levels of phosphorus (P) supply. One group of genotypes was a random collection from soils relatively high in P, the other group consisted of genotypes collected from soils low in P. Shoot dry weight and a number of attributes of the youngest mature leaf were measured. There was a significant group x P interaction for shoot dry weight, leaf total P concentration, inorganic P concentration and soluble protein concentration. This indicates that, on average, the two groups had different responses to P which suggests that there may be some differentiation of the genotypes according to the P availability at the site of origin. Further analysis suggested that two genotypes in particular were responsible for the significant interaction. Significant differences in attributes among genotypes also mean that, if not taken into account, they may obscure other desired observations, especially in a variable, outbreeding species such as white clover.

ISSN:0190-4167    

DOI:10.1080/01904168809363795

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Sorghum [Sorghum bicolor(L.) Moench] grown in a ratoon cropping system is an alternative double‐cropping scheme for the southeastern U.S. Visual symptoms of nitrogen (N) deficiency in the early growth of the ratooned crop suggested that improved N fertilizer management might increase grain yields of the ratooned crop. Five hybrids: Coker 7737, Gold Kist 802G, Northrup King NK 2660, DeKalb DK‐59 and Pioneer Brand 8311 were grown in a ratoon cropping system on a Greenville sandy clay loam (Rhodic Paleudult). Nitrogen fertilizer treatments for the ratoon crop were applied at flowering of the planted crop (90 kg ha‐1), immediately following ratooning (90 kg ha‐1) or split between flowering of the planted crop (45 kg ha‐1) and ratooning (45 kg ha‐1). The N concentrations in the grain and stover of the planted crop were increased by both N rates applied at flowering of the planted crop. Grain yields of the planted or ratooned crops were not affected by the timing of N fertilizer application for the ratoon crop. Nitrogen uptake was higher in the ratoon crop when N was applied following ratooning. Timing of N fertilizer applications for the ratoon crop can affect N uptake by the ratoon crop, however the success of the ratoon system depends on the adaptability of the hybrids.

ISSN:0190-4167    

DOI:10.1080/01904168809363796

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Oxamide, a slow‐release N source, may have anti‐ethylene growth regulator effects as well as nutritional effects on plants. Responses of wheat (Triticum aestivumL.) to foliar application of oxamide and other N sources, of soybean(Glycine maxL. Merr.) to foliar and soil applications of oxamide, and of both species to oxamide in hydroponics solution were measured to assess growth regulator and nutritional effects. Wheat studies were at two locations for two years and soybean studies were at one location for one year. Foliar applications of oxamide to wheat increased grain protein concentration in three of four tests but were less effective than urea foliar applications. Oxamide supplied as foliar or soil treatment to soybean increased the test weight but had little other discernable effect. In hydroponics culture, oxamide was inferior to nitrate as an N source. We concluded that oxamide did not function as a growth regulator and that plant responses were determined by solubility, degradability, and penetrability of the compound.

ISSN:0190-4167    

DOI:10.1080/01904168809363797

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904168809363789

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor