Limits...
Nutrients Limiting Soybean (glycine max l) Growth in Acrisols and Ferralsols of Western Kenya.

Keino L, Baijukya F, Ng'etich W, Otinga AN, Okalebo JR, Njoroge R, Mukalama J - PLoS ONE (2015)

Bottom Line: Nutrients omission resulted in their significantly low concentration in plant tissues than the complete treatment.Nitrogen significantly improved SDWs in soils from Kakamega and Butula.The results also signify necessity of application of small quantities of N for initial soybean use.

View Article: PubMed Central - PubMed

Affiliation: Department of Soil Science, University of Eldoret, Eldoret, Kenya.

ABSTRACT
Low soybean yields in western Kenya have been attributed to low soil fertility despite much work done on nitrogen (N) and phosphorus (P) nutrition leading to suspicion of other nutrient limitations. To investigate this, a nutrient omission trial was set up in the greenhouse at the University of Eldoret-Kenya to diagnose the nutrients limiting soybean production in Acrisols from Masaba central and Butere sub-Counties, and Ferralsols from Kakamega (Shikhulu and Khwisero sub-locations) and Butula sub-Counties and to assess the effect of liming on soil pH and soybean growth. The experiment was laid out in a completely randomized design with ten treatments viz; positive control (complete), negative control (distilled water), complete with lime, complete with N, minus macronutrients P, potassium (K), calcium (Ca), magnesium (Mg) and sulphur (S) and with, micro-nutrients boron (B), molybdenum (Mo), manganese (Mn), copper (Cu) and zinc (Zn) omitted. Visual deficiency symptoms observed included interveinal leaf yellowing in Mg omission and N addition and dark green leaves in P omission. Nutrients omission resulted in their significantly low concentration in plant tissues than the complete treatment. Significantly (P≤ 0.05) lower shoot dry weights (SDWs) than the complete treatment were obtained in different treatments; omission of K and Mg in Masaba and Shikhulu, Mg in Khwisero, K in Butere and, P, Mg and K in Butula. Nitrogen significantly improved SDWs in soils from Kakamega and Butula. Liming significantly raised soil pH by 9, 13 and 11% from 4.65, 4.91 and 4.99 in soils from Masaba, Butere and Butula respectively and soybean SDWs in soils from Butere. The results show that, poor soybean growth was due to K, Mg and P limitation and low pH in some soils. The results also signify necessity of application of small quantities of N for initial soybean use.

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Related in: MedlinePlus

Illustration of the set up of the double pot experiment.
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pone.0145202.g001: Illustration of the set up of the double pot experiment.

Mentions: Assessment of limiting nutrients was carried out in the greenhouse at the University of Eldoret located at 0° 34' N and 35° 18' E. The experiment adopted the so called double pot technique[25]. This method offers an easy and rapid means of identifying the nutrients that are in short supply in the soils. In this technique, two pots are used whereby the upper pot (pot 1, Fig 1) has a gauze fitted at the bottom and is filled with soil. The lower pot (pot 2, Fig 1) is filled with nutrient solution and has a lid to support the upper pot. A space of approximately 1 cm is left between the bottom of the upper pot and the nutrient solution to allow oxygen supply to the plant roots. The plant is therefore provided with two sources of nutrients (test soil and nutrient solution) for its simultaneous uptake. It is during the initial stage of growth (germination) that the plant obtains nutrients from the soil alone. Seeds or seedlings are planted in the soil and as the plants grow the roots pass through the gauze and reach the nutrient solution in the lower pot. When a nutrient is omitted from the nutrient solution, the plant can take it up from the soil only. The absence of an element can be seen from the deficiency symptoms developed such as limited growth and leaf chlorosis. The symptoms can be visible in the early growth stages and thus can be used to draw conclusions for fertilizer recommendations. The technique ensures those nutrients applied such as P and K are not fixed by the soil as it would be the case if soil alone (single pot) is used. In this experiment, the upper pots were provided by parts of a common sewage pipe with 9 cm diameter. A mesh was cut into small pieces and tied to their bottom, to prevent the soil from falling into the solution, but providing passage for the roots. Small plastic pots of 2 l volume served as the bottom pots.


Nutrients Limiting Soybean (glycine max l) Growth in Acrisols and Ferralsols of Western Kenya.

Keino L, Baijukya F, Ng'etich W, Otinga AN, Okalebo JR, Njoroge R, Mukalama J - PLoS ONE (2015)

Illustration of the set up of the double pot experiment.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4696802&req=5

pone.0145202.g001: Illustration of the set up of the double pot experiment.
Mentions: Assessment of limiting nutrients was carried out in the greenhouse at the University of Eldoret located at 0° 34' N and 35° 18' E. The experiment adopted the so called double pot technique[25]. This method offers an easy and rapid means of identifying the nutrients that are in short supply in the soils. In this technique, two pots are used whereby the upper pot (pot 1, Fig 1) has a gauze fitted at the bottom and is filled with soil. The lower pot (pot 2, Fig 1) is filled with nutrient solution and has a lid to support the upper pot. A space of approximately 1 cm is left between the bottom of the upper pot and the nutrient solution to allow oxygen supply to the plant roots. The plant is therefore provided with two sources of nutrients (test soil and nutrient solution) for its simultaneous uptake. It is during the initial stage of growth (germination) that the plant obtains nutrients from the soil alone. Seeds or seedlings are planted in the soil and as the plants grow the roots pass through the gauze and reach the nutrient solution in the lower pot. When a nutrient is omitted from the nutrient solution, the plant can take it up from the soil only. The absence of an element can be seen from the deficiency symptoms developed such as limited growth and leaf chlorosis. The symptoms can be visible in the early growth stages and thus can be used to draw conclusions for fertilizer recommendations. The technique ensures those nutrients applied such as P and K are not fixed by the soil as it would be the case if soil alone (single pot) is used. In this experiment, the upper pots were provided by parts of a common sewage pipe with 9 cm diameter. A mesh was cut into small pieces and tied to their bottom, to prevent the soil from falling into the solution, but providing passage for the roots. Small plastic pots of 2 l volume served as the bottom pots.

Bottom Line: Nutrients omission resulted in their significantly low concentration in plant tissues than the complete treatment.Nitrogen significantly improved SDWs in soils from Kakamega and Butula.The results also signify necessity of application of small quantities of N for initial soybean use.

View Article: PubMed Central - PubMed

Affiliation: Department of Soil Science, University of Eldoret, Eldoret, Kenya.

ABSTRACT
Low soybean yields in western Kenya have been attributed to low soil fertility despite much work done on nitrogen (N) and phosphorus (P) nutrition leading to suspicion of other nutrient limitations. To investigate this, a nutrient omission trial was set up in the greenhouse at the University of Eldoret-Kenya to diagnose the nutrients limiting soybean production in Acrisols from Masaba central and Butere sub-Counties, and Ferralsols from Kakamega (Shikhulu and Khwisero sub-locations) and Butula sub-Counties and to assess the effect of liming on soil pH and soybean growth. The experiment was laid out in a completely randomized design with ten treatments viz; positive control (complete), negative control (distilled water), complete with lime, complete with N, minus macronutrients P, potassium (K), calcium (Ca), magnesium (Mg) and sulphur (S) and with, micro-nutrients boron (B), molybdenum (Mo), manganese (Mn), copper (Cu) and zinc (Zn) omitted. Visual deficiency symptoms observed included interveinal leaf yellowing in Mg omission and N addition and dark green leaves in P omission. Nutrients omission resulted in their significantly low concentration in plant tissues than the complete treatment. Significantly (P≤ 0.05) lower shoot dry weights (SDWs) than the complete treatment were obtained in different treatments; omission of K and Mg in Masaba and Shikhulu, Mg in Khwisero, K in Butere and, P, Mg and K in Butula. Nitrogen significantly improved SDWs in soils from Kakamega and Butula. Liming significantly raised soil pH by 9, 13 and 11% from 4.65, 4.91 and 4.99 in soils from Masaba, Butere and Butula respectively and soybean SDWs in soils from Butere. The results show that, poor soybean growth was due to K, Mg and P limitation and low pH in some soils. The results also signify necessity of application of small quantities of N for initial soybean use.

Show MeSH
Related in: MedlinePlus