摘要:

Narrow‐leafed lupin(Lupinus angustifoliusL.) seed with phosphorus (P) concentrations of 0.21, 0.26 or 0.43% were graded to uniform size (128 ± 5 mg) and grown in two glasshouse experiments to examine the effects of seed P concentration on early shoot, root and nodule growth, and its response to external P supply.

ISSN:0190-4167    

DOI:10.1080/01904169209364390

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The evaluation of soybean genotypes for resistance to iron deficiency through field experiments is complicated by variation in symptom expression. The objective of this study was to develop a tissue culture technique that could distinguish between Fe‐efficient and Fe‐inefficient genotypes. Ten soybean genotypes varying in sensitivity to iron deficiency were planted at 5 locations and rated based on chlorosis expression. For the lab evaluation, friable callus of the ten genotypes was placed on a 4MSII medium amended with 10 mM NaHCO3. Callus growth reduction relative to a control medium without NaHCO3was recorded. Callus weight of all cultivars was affected by the addition of NaHCO3however, significant differences in growth reduction among genotypes was observed. The high correlation between callus growth reduction and field chlorosis ratings observed (r2=0.92) and the fact that the expiant source plant can be grown to produce seed indicates that this technique would be useful in a soybean breeding program.

ISSN:0190-4167    

DOI:10.1080/01904169209364391

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

In a pot experiment a water extract from ryegrass(Lolium perenne)containing 21 mg/L selenium (Se) was sprayed on ryegrass, and the uptake of Se was compared with the uptake of Se applied as sodium selenite. The amount of Se recovered from the plants (0 to 53 mg/kg) was a linear function of the amount of Se applied (0 to 130 g/ha), both for the Se in the extract and for the sodium selenite. A total of 2.8 times more Se was recovered from the plants sprayed with the extract than from the plants sprayed with sodium selenite. When the plants were washed with Triton X‐100 the difference was still higher: from the ryegrass sprayed with the extract 5.3 times more Se was recovered from the grass sprayed with the extract than from the grass sprayed with sodium selenite.

ISSN:0190-4167    

DOI:10.1080/01904169209364392

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The primary nitrogen forms utilized by plants are ammonium and nitrate. Although the importance of nutrients other than nitrogen for proper turfgrass growth is well established, the amounts of these nutrients in the plant tissue in relation to the use of different N‐forms has not been clearly documented. This study was conducted under greenhouse conditions to determine the effect of N‐form and cutting regime on growth, macronutrient, and micronutrient content of creeping bentgrass(Agrostis palustrisHuds. ‘Penncross'). Treatments consisted of 100% NO3−(calcium nitrate), 100% NH4+(ammonium sulfate), and a 50:50 ratio of NH4+:NO3−. Half the turfgrass plants were maintained at a height of 1 cm (cut), while the other half of the plants were not cut until the end of the study (uncut). The uncut 50:50 treatment yielded the highest shoot, verdure, and total plant dry matter, while the uncut NO3−treatment produced the highest root dry matter. The uncut NH4+treatment yielded the least shoot, root, and total plant dry matter. Plants of the uncut NO3−treatment had greater accumulation of macronutrients in the shoot and root tissue compared to plants of the NH4+treatment. The uncut NO3−and 50:50 treatments had higher total accumulation of micronutrients compared to the uncut NH4+‐treated plants. The cut NO3−treatment resulted in the highest macronutrient and micronutrient contents in the root tissue in comparison to other cut treatments. The cut treatments had the highest percentage accumulation of nutrients in the verdure tissue, while the uncut treatments had the highest percentage accumulation of nutrients in the shoot tissue.

ISSN:0190-4167    

DOI:10.1080/01904169209364393

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Decreasing winter pasture productivity in unlimed Ultisols has been associated with increased soil acidity due to fertilizer N application. The susceptibility of cool season grasses to soil acidity and associated infertility factors that result in reduced forage yield are not well understood. This field study was undertaken to evaluate the effects of factorial combinations of limestone and P applications on annual ryegrass(Lolium multiflorumLam. ‘Marshall') dry matter production and tissue mineral concentrations on a strongly acid (pH 4.7), sandy soil. Limestone was applied to a Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult) at rates of 0, 672, or 3808 kg ha‐1. Phosphorus was applied to split plots at rates of 0, 30, 60, 90, 120, 240, or 480 kg P ha‐1. Over three harvest years, ryegrass yields increased 90 to 750% and 25 to 80% at the highest lime and P rates, respectively. In the second year, yield response to applied P was significantly less at the high lime rate which indicated that liming made soil P more plant available. Lime and applied P increased plant tissue P, Ca, and Mg concentrations. Yield was positively correlated with soil pH, P, Ca, and Mg and negatively related to soil K and Al. Clear relationships between individual soil test levels and leaf mineral concentrations with yield fluctuations could not be established because these variables were inextricably related to the lime and P rates. Nevertheless, excessive soil Al, coupled with inadequate P, Ca, and Mg availability, were indicated as important nutritional factors limiting annual ryegrass growth in unlimed soil.

ISSN:0190-4167    

DOI:10.1080/01904169209364394

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Nitrogen‐form effect on nutrient uptake and the subsequent concentration of nutrients in turfgrass plant tissue has not been thoroughly investigated. This study evaluated the effects of clipping regime and N‐form on the tissue concentration of macronutrients and micronutrients and macronutrient uptake in ‘Penncross’ creeping bentgrass(Agrostis palustrisHuds.). Turfgrass plugs were grown under greenhouse conditions in a modified Hoagland's solution with a combination of three nutrient solutions (100% NO3−, 100% NH4+, and 50:50 ratio of NH4+:NO3−) and two cutting regimes (cut and uncut). Concentrations of macronutrients and micronutrients were determined for shoot, root and verdure. Nutrient uptake was determined weekly. Uncut NO3−‐treated plants accumulated higher concentrations of K, Ca, Mg, B and Cu in the shoot tissue; P, K, Ca, Mg, B, Cu, Mn and Zn in the root tissue; and P, Ca, Mg, B, Fe and Mn in the verdure compared to uncut NN4+‐treated plants. Nitrate uptake was greater with uncut NO3−‐treated plants than was NH4+absorption with uncut NH4+‐treated plants. Plants grown with the uncut 50:50 treatment adsorbed more NH4+than NO3−. Plants grown with the uncut NO3−and 50:50 treatments adsorbed higher amounts of P, K, and Ca compared to the NH4+treatment. The cut NO3−‐treated plants accumulated higher concentrations of K in the shoot tissue; P, Ca, Mg, B, Cu, Fe and Mn in the root tissue; and B in the verdure than did the cut NH4+‐treated plants. Cut NO3−‐treated plants adsorbed less NO3−than did cut NH4+‐treated plants adsorbed NH4+. The cut 50:50 treatment adsorbed more NH4+than NO3−. Plants grown with NO3−and 50:50 treatments, under both cutting regimes, resulted in higher concentrations of most macro‐ and micronutrients and greater nutrient uptake compared to the NH4+‐treated plants.

ISSN:0190-4167    

DOI:10.1080/01904169209364395

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Spring wheat (Triticum aestivumL.) dry matter (DM), N content and tillering are increased by increasing the proportion of N available to the plant as NH4(enhanced ammonium supply‐EAS) at soil pH ≥ 7.0. Using different N sources to provide different levels of EAS effects soil pH and electrical conductivity (EC) as well as soil NH4. Both pH and EC may affect plant growth and response to EAS.

ISSN:0190-4167    

DOI:10.1080/01904169209364396

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Water samples collected in the Mermentau River Basin over several years at Lousiana Department of Environmental Quality monitoring sites contained high levels of total solids and nutrients during the spring that were highly correlated to pre‐ and post‐plant discharges from rice fields. This study was developed to evaluate the potential of selected management practices (MP's) for reducing total solids, nutrients and pesticides from discharge water in order to improve the surface water quality in southwest Louisiana. Five rice plots located on the Rice Research Station in Crowley, LA represented the different MP's to be evaluated. The five water seeding MP's were: a.1‐no till; a.2‐water cultivation with 30‐day settling; a.3‐dry cultivation with clear water planting; a.4‐mudding‐in with vegetated filter, and b‐mudding‐in (control).

ISSN:0190-4167    

DOI:10.1080/01904169209364397

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Cloned stem cuttings of geranium (Pelargonium peltatum)were maintained in control and mineral deficient solutions for five weeks. Hydroponic solutions were formulated to be deficient in a single mineral;e.g., ‐Ca, ‐Fe, ‐Mg, ‐N, and ‐P. Positive control solutions contained all macro and micronutrients, while negative controls consisted of double distilled water. Weights and numbers of all organs of the shoot were determined, as was an analysis of adventitious roots. Plants grown in ‐Ca solutions characteristically manifested reduced organ weights and numbers as compared to plants grown in other mineral deficiencies and both controls. Examples of reduced values recorded in ‐Ca plants, as compared to the negative control plants, were: (i) a 60% decrease in overall plant weight, (ii) a 40% reduction in the total weight of leaves per plant, (iii) a 50% reduction in stem weight, (iv) a 60% drop in the weight of the stem base and associated adventitious roots, (v) a 30% decline in inflorescence weight, (vi) a 20% reduction in the number of leaves produced per plant, and (vii) a 20% decrease in the weight of individual leaves. Perhaps the most striking developmental distinction was the absence of adventitious roots in ‐Ca plants. Cuttings in distilled water produced an average of nearly 30 roots near the stem base. Anatomical examination of stem bases from plants grown in Ca‐deficient nutrient solutions revealed a few initiated roots in only one instance, but all roots were poorly developed and few in number. Most stem bases in ‐Ca did not have any initiated root primordia. It is believed that Ca has the capability of ameliorating mineral toxicity induced by other elements in the nutrient solution.

ISSN:0190-4167    

DOI:10.1080/01904169209364398

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169209364399

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor