Response of Soybean [Glycine max (L.) Merrill] to Sources and Levels of Phosphorus

Abstract

<p>A field experiment was conducted during rainy seasons of 2007-2009 in India (Manipur) to study the effect of different sources and levels of phosphorus on productivity of soybean [<em>Glycine max</em> (L.) Merrill]. The treatments consisted of four sources of phosphorus [Single super phosphate (SSP), Di-ammonium phosphate (DAP), Single super phosphate (SSP)+Phosphate solubilizing bacteria (PSB), Di-ammonium phosphate (DAP)+Phosphate solubilizing bacteria (PSB)], four levels of phosphorus (20, 40, 60 and 80 kg P₂O₅ ha^-1) and one absolute control(without any fertilizer and PSB). Application of SSP+PSB produced significantly higher number of nodules per plant, dry weight of nodules per plant, number of pods per plant and 100-seed weight than the other treatments. Maximum grain yield and total phosphorus uptake were also recorded when using SSP+PSB. Yield attributing characters, grain and stover yield were increased with increasing levels of phosphorus. Regarding evaluation of various efficiency fractions of soybean, agronomic efficiency, physiological efficiency and phosphorus use efficiency had more pronounced effects on combined application of SSP+PSB. However, apparent recovery of phosphorus was higher in DAP+PSB due to higher stover yield and higher phosphorus uptake. Among the different levels the efficiency fractions increase up to 60 kg P₂O₅ ha^-1 and declined at 80 kg P₂O₅ ha^-1.</p

Effect of Phosphorus Application and Varieties on Grain Yield and Yield Components of Common Bean (Phaseolus vulgaris L.)

“…As to the present experiment, the increase in P rate increased pods/plant, seeds/pod and grain yield for common bean (Kassa et al, 2014;Turuko and Mohammed, 2014) and soybean (Devi et al, 2012). However, the low increase or decline in these parameters beyond 13.2 kg haG 1 P rate despite the low soil P content (1.5 ppm) observed in present experiment could be related to the reaching of P supply to the optimal level or limitation of yield potential of bean varieties studied.…”

“…As to the present experiment, the decrease in agronomic efficiency with the increase in P supply has been reported for maize (Hussein, 2009), common bean (Gidago et al, 2011;Girma et al, 2014), soybean (Devi et al, 2012) and tef (Balcha, 2014). This could be due to the limiting effect of other nutrients with increasing level of P (Mengel and Kirkby, 2001), or because the rate of increase in grain yield was less than the rate of increase in P supply.…”

“…Moreover, usually less than 15% of P fertilizer applied is recovered from the soil by the crop grown immediately after application (Greenwood, 1981). Even though addition of P fertilizer increases grain yield in many crops such as tef (Deressa et al, 2004;Balcha, 2014),wheat (Gunes et al, 2006), sorghum (Akram et al, 2007), maize (Hussein, 2009), common bean (Fageria et al, 2010;Gidago et al, 2011;Girma et al, 2014;Kassa et al, 2014) and soybean (Devi et al, 2012), the application of excess P fertilizer has been associated with environmental pollution (Mengel and Kirkby, 2001;Marschner, 2012).…”

Effect of Phosphorus Rates and Varieties on Grain Yield, Nutrient Uptake and Phosphorus Efficiency of Tef [&lt;i&gt;Eragrostis tef&lt;/i&gt; (Zucc.) Trotter]

“…As to the present experiment, the increase in P rate increased grain yield in tef [24] and soybean [25]; grain yield and total biomass in maize [19], wheat [26], amaranth [27] and sorghum [28]; total biomass in rice [20,29]; and plant height in soybean [25], sorghum [28] and tef [30], because P is involved in several energy transformation and biochemical reactions for plant growth and development. Such an increase in tef performance observed in present experiment with P supply would also indicate the deficiency of P in this particular soil.…”

“…As to the present experiment, the increase in P supply increased grain P in maize [19,34], amaranth [27] and sorghum [28], grain N and K in maize [34], total plant P in maize [19], soya bean [25], wheat [26], rice [20,29] and sorghum [28], and total plant N and K in sorghum [28]. The increase in nutrient accumulation with the increase in P supply could be related to improved root system development [25], and increased availability of nutrients due to increased soil pH [27].…”