Effect of Sources, Split and Foliar Application of KCl and KClO3 on Availability and Uptake of Phosphorus in Aerobic Rice

Aim: To investigate the effect of KCl and KClO3 as sources of potassium in aerobic rice with four types of split doses and two levels of foliar applications of potassium.

Study Design: The experiment was laid out in Randomized Block Design with three replications.

Place and Duration of Study: Pandit Jawaharlal Nehru College of Agriculture and Research Institute, Karaikal, Puducherry.

Methodology : The rice variety PMK 4 was tested with two sources of potassium viz., Potassium chloride (KCl) and Potassium chlorate (KClO3), four types of split application viz., K control (S1), basal with no split (S2), two splits (S3) and three splits (S4) along with foliar application treatments viz., no foliar (F1) and foliar spray (F2).

Results: The results of a field experiment revealed that the two splits of potassium increased the available P at the active tillering stage and harvest stage. Whereas, three splits increased the available P at panicle imitation and flowering stage. The KCl recorded higher available P at panicle initiation and harvest stages. The high phosphorus uptake was recorded in panicle initiation and flowering stages by three splits application of potassium. In grain also, especially the three splits through KClO3 recorded higher P uptake.

Conclusion: The split applications tested in this investigation influenced the available phosphorus status in soil and phosphorus uptake. Increase in splits of potassium increased the P uptake. This result is in agreement with the results of Mitra et al. [1] who observed a significant increase in the uptake of N, P, K and S by increased level of K in Kharif rice.