Phosphorus Efficiency Mechanisms of Two Wheat Cultivars as Affected by a Range of Phosphorus Levels in the Field

A comparative study was made of the growth and development of the shoot apex/inflorescence in two contrasting spring wheat (Triticum aestivum L.) cultivars: Marquis—a standard height, day-length-sensitive type; and Pitic 62—a semidwarf, Norin 10 derivative with relatively low day-length sensitivity. The effects of 8-, 12-, 16-, 20-, and 24-h photoperiods and of two nitrogen levels in 12 and 20 h on both cultivars were determined, as well as those of two phosphorus levels on Marquis in 20 h.Apical primordium production continued for a longer duration in Pitic than in Marquis, and the initiation of spikelet primordia was delayed. Spikelet development was more synchronous in Pitic than in Marquis in all treatments. Apical spikelet formation always coincided in both cultivars with the initiation of rachis internode extension. Inflorescence development after termination of spikelet primordia formation was as fast in Pitic as in Marquis (or faster in short photoperiods).In general, increasing N increased the rate and duration of primordium production (apical spikelet formation occurring later at high N), and delayed inflorescence development and extension. These effects were more pronounced in Pitic, resulting in much greater N responses for spikelet and grain numbers per spike, and for grain yields per spike. Effects of high P were similar to those of high N. Increasing photoperiod increased the rate, but decreased the duration of primordium production, and accelerated the development and the extension growth of the inflorescence.The results are discussed in relation to a postulated involvement of endogenous gibberellins and inhibitors in the regulation of inflorescence growth and development.

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Genotypic variation in phosphorus efficiency between wheat cultivars grown under greenhouse and field conditions

Soil Science & Plant Nutrition ◽

10.1111/j.1747-0765.2006.00068.x ◽

2006 ◽

Vol 52 (4) ◽

pp. 470-478 ◽

Cited By ~ 39

Author(s):

Aydin Gunes ◽

Ali Inal ◽

Mehmet Alpaslan ◽

Ismail Cakmak

Keyword(s):

Genotypic Variation ◽

Field Conditions ◽

Phosphorus Efficiency ◽

Wheat Cultivars

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A sand culture experiment to compare the effects of sulphur on five wheat cultivars (T. aestivum L.)

Australian Journal of Agricultural Research ◽

10.1071/ar9740369 ◽

1974 ◽

Vol 25 (3) ◽

pp. 369 ◽

Cited By ~ 20

Author(s):

MJ Archer

Keyword(s):

Grain Yield ◽

Phenotypic Expression ◽

Sand Culture ◽

Wheat Cultivars ◽

Nitrogen And Phosphorus ◽

Culture Experiment ◽

Chemical Mechanisms ◽

Matter Production ◽

Physico Chemical ◽

Phosphorus Levels

A glasshouse sand culture experiment was conducted to determine the effects of sulphur supplied at 10,375 and 875µM concentrations on total dry matter production per plant (TDM), grain yield, harvest index (HI), yield components, nitrogen, sulphur and phosphorus levels in herbage and grain samples of two vitreous grained (Stockade and Gabo) and three non-vitreous grained (Insignia, Olympic and Summit) wheat cultivars (T. aestivum L.). Pelshenke doughball fermentation tests were done on wholemeal samples from all treatments.Stockade and Gabo had higher TDM than Insignia, Olympic and Summit at 10µM sulphur concentration, but relatively lower harvest indices. At 375µM sulphur, TDM increased for all cultivars; Gabo and Stockade continued to have relatively higher TDM, but Stockade produced only half the increase of any other cultivar. However, Stockade doubled its HI which, in turn, was double the increase recorded by Olympic and Summit. Insignia failed to increase its HI. Only Stockade showed increased TDM at 875µM sulphur. Olympic had the highest HI values at both 375 and 875µM sulphur. Similar grain yield increases for all cultivars were largely attained by differential grain number-grain size combinations. The higher sulphur supplies therefore stimulated the translocation of photosynthates to the developing grains and/or shifted the location of most rapid cell division from vegetative to reproductive sites. Stockade and Gabo had relatively higher percentages of grain sulphur at 10µM sulphur than the other cultivars and Stockade continued to have the highest percentage of grain sulphur at 375 and 875µM concentration. Except for a marked fall by Insignia, an increasing sulphur supply did not affect the distribution of sulphur within the plants as the indices for percentage sulphur remained largely unchanged. However, the distribution of nitrogen and phosphorus from straw to grain were both stimulated. Stockade and Gabo had relatively larger increases in their indices of percentage nitrogen, but the non-vitreous grained cultivars showed relatively larger increases in the percentage of nitrogen in the grain. Comparatively poor Pelshenke results, especially for Stockade, at I0µM sulphur, indicate an adverse affect of sulphur deficiency on grain quality. The experiment has shown that variation in sulphate sulphur supply differentially affected the biological and physico-chemical mechanisms controlling the optimum phenotypic expression of five wheat genotypes (cultivars). Part of these mechanisms involves close interrelationships and interactions between the uptake and/or metabolism of sulphur, phosphorus and nitrogen anions. Stockade was a particularly responsive cultivar to sulphur, while Insignia was relatively insensitive.

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PHOSPHORUS REQUIREMENT OF TAMBAQUI FINGERLINGS

Revista Caatinga ◽

10.1590/1983-21252019v32n324rc ◽

2019 ◽

Vol 32 (3) ◽

pp. 795-804

Author(s):

THALLES JOSÉ REGO SOUSA ◽

MARCOS ANTONIO DELMONDES BOMFIM ◽

FELIPE BARBOSA RIBEIRO ◽

SYLVIA SANAE TAKISHITA ◽

DAYANA DA CANCEIÇÃO DA COSTA

Keyword(s):

Weight Gain ◽

Feed Efficiency ◽

Specific Growth ◽

Phosphorus Efficiency ◽

Experimental Unit ◽

Randomized Design ◽

Phosphorus Requirement ◽

Completely Randomized Design ◽

Phosphorus Intake ◽

Phosphorus Levels

ABSTRACT The objective of this study was to determine the digestible phosphorus requirement in rations for tambaqui fingerlings (Colossoma macropomum). 900 fingerlings (0.51 ± 0.06 g) were used in a completely randomized design with six treatments, five replicates, and thirty fish per experimental unit. The treatments consisted of six diets with different digestible phosphorus levels (0.12, 0.33, 0.54, 0.75, 0.95, and 1.16%). The fish were fed six times a day, for 63 days. Performance, feed efficiency, and the daily protein, fat, ash, and phosphorus deposition rates of fish were evaluated. The treatments did not influence the feed intake. The elevation of phosphorus levels increased the digestible phosphorus intake linearly, and improved of quadratic form the weight gain, specific growth rate, feed:gain ratio, protein efficiency for weight gain, and daily protein, fat, ash, and phosphorus depositions up to the estimated levels of 0.64, 0.66, 0.70, 0.70, 0.62, 0.62, 0.70, 0.71%, respectively. The phosphorus efficiency for weight gain worsened with the elevation of phosphorus levels. The recommendation of digestible phosphorus level in rations for tambaqui fingerlings to optimize weight gain and body phosphorus deposition is 0.71%, which corresponds to the estimated level of 1.04% total phosphorus.

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