A 2-year field experiment was conducted to assess the effect of applied zinc(Zn) on the seed yield of pea(Pisum sativum L.) and to determine the internal Zn requirement of pea with emphasis on the seed and leaves as i...A 2-year field experiment was conducted to assess the effect of applied zinc(Zn) on the seed yield of pea(Pisum sativum L.) and to determine the internal Zn requirement of pea with emphasis on the seed and leaves as index tissues.The experiment was carried out at two different locations(Talagang,Chakwal district and National Agricultural Research Centre(NARC),Islamabad) in the Potohar Plateau,Pakistan by growing three pea cultivars(Green feast,Climax,and Meteor).The soils were fertilized with 0,2,4,8,and 16 kg Zn ha^(-1) along with recommended basal fertilization of nitrogen(N),phosphorus(P),potassium(K),and boron(B).Zinc application increased seed yield significantly for all the three cultivars.Maximum increase in the pea seed yield(2-year mean) was21%and 15%for Green feast,28%and 21%for Climax,and 34%and 26%for Meteor at Talagang and NARC,respectively.In all cultivars,Zn concentrations in leaves and seed increased to varying extents as a result of Zn application.Fertiliser Zn requirement for near-maximum seed yield varied from 3.2 to 5.3 kg ha^(-1) for different cultivars.Zinc concentrations of leaves and seeds appeared to be a good indicator of soil Zn availability.The critical Zn concentration range sufficient for 95%maximum yield(internal Zn requirement)was 42-53 mg kg^(-1) in the pea leaves and 45-60 mg kg^(-1) in the seeds of the three pea cultivars studied.展开更多
Leaching of boron （B） and zinc （Zn） can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied us...Leaching of boron （B） and zinc （Zn） can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied using 8.4 cm diameter × 28 cm long intact columns from two calcareous soil series with differing clay contents and vadose zone structures： Lyallpur soil series, clay loam （fine-silty, mixed, hyperthermic Ustalfic Haplargid）, and Sultanpur soil series, sandy loam （coarse-silty, mixed, hyperthermic Ustollic Camborthid）. The adsorption isotherms were developed by equilibrating soil with 0.01 tool L^-1 CaCl2 aqueous solution containing varying amounts of B and Zn and were fitted to the Langmuir equation. The B and Zn breakthrough curves were fitted to the two-domain convective-dispersive equation. At the end of the leaching experiment, 0.11 L 10 g L^-1 blue dye solution was also applied to each column to mark the flow paths. The Lyallpur soil columns had a slightly greater adsorption partition coefficient both for B and Zn than the Sultanpur soil columns. In the Lyallpur soil columns, B arrival was immediate but the peak concentration ratio （the concentration in solution at equilibrium/concentration applied） was lower than that in the Sultanpur soil columns. The breakthrough of B in the Sultanpur soil columns occurred after about 10 cm of cumulative drainage in both the columns; the rise in effluent concentration was fast and the peak concentration ratio was almost 1. Zinc leaching through the soil columns was very limited as only one column from the Lyallpur soil series showed Zn breakthrough in the effluent where the peak concentration ratio was only 0.05. This study demonstrates the effect of soil structure on B transport and has implications for the nutrient management in field soils.展开更多
基金supported by the project of Micronutrient Management for Sustaining Major Cropping Systemsfunded by Ministry of Food,Agriculture and Livestock,Go-vernment of Pakistan,Islamabad
文摘A 2-year field experiment was conducted to assess the effect of applied zinc(Zn) on the seed yield of pea(Pisum sativum L.) and to determine the internal Zn requirement of pea with emphasis on the seed and leaves as index tissues.The experiment was carried out at two different locations(Talagang,Chakwal district and National Agricultural Research Centre(NARC),Islamabad) in the Potohar Plateau,Pakistan by growing three pea cultivars(Green feast,Climax,and Meteor).The soils were fertilized with 0,2,4,8,and 16 kg Zn ha^(-1) along with recommended basal fertilization of nitrogen(N),phosphorus(P),potassium(K),and boron(B).Zinc application increased seed yield significantly for all the three cultivars.Maximum increase in the pea seed yield(2-year mean) was21%and 15%for Green feast,28%and 21%for Climax,and 34%and 26%for Meteor at Talagang and NARC,respectively.In all cultivars,Zn concentrations in leaves and seed increased to varying extents as a result of Zn application.Fertiliser Zn requirement for near-maximum seed yield varied from 3.2 to 5.3 kg ha^(-1) for different cultivars.Zinc concentrations of leaves and seeds appeared to be a good indicator of soil Zn availability.The critical Zn concentration range sufficient for 95%maximum yield(internal Zn requirement)was 42-53 mg kg^(-1) in the pea leaves and 45-60 mg kg^(-1) in the seeds of the three pea cultivars studied.
文摘Leaching of boron （B） and zinc （Zn） can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied using 8.4 cm diameter × 28 cm long intact columns from two calcareous soil series with differing clay contents and vadose zone structures： Lyallpur soil series, clay loam （fine-silty, mixed, hyperthermic Ustalfic Haplargid）, and Sultanpur soil series, sandy loam （coarse-silty, mixed, hyperthermic Ustollic Camborthid）. The adsorption isotherms were developed by equilibrating soil with 0.01 tool L^-1 CaCl2 aqueous solution containing varying amounts of B and Zn and were fitted to the Langmuir equation. The B and Zn breakthrough curves were fitted to the two-domain convective-dispersive equation. At the end of the leaching experiment, 0.11 L 10 g L^-1 blue dye solution was also applied to each column to mark the flow paths. The Lyallpur soil columns had a slightly greater adsorption partition coefficient both for B and Zn than the Sultanpur soil columns. In the Lyallpur soil columns, B arrival was immediate but the peak concentration ratio （the concentration in solution at equilibrium/concentration applied） was lower than that in the Sultanpur soil columns. The breakthrough of B in the Sultanpur soil columns occurred after about 10 cm of cumulative drainage in both the columns; the rise in effluent concentration was fast and the peak concentration ratio was almost 1. Zinc leaching through the soil columns was very limited as only one column from the Lyallpur soil series showed Zn breakthrough in the effluent where the peak concentration ratio was only 0.05. This study demonstrates the effect of soil structure on B transport and has implications for the nutrient management in field soils.
