Effect of Sources, Split and Foliar Application of KCl and KClO3 on Availability and Uptake of Nitrogen 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 field experiment revealed that the N availability in soil was more at all stages of crop growth by two and three split doses of potassium. The KClO3 increased the available N status at active and panicle initiation stages. Whereas in flowering stage, the KCl recorded the higher available N status in soil. The nitrogen uptake at active tillering stage and flowering stage was evidently improved with three split doses of potassium. Whereas in panicle initiation stage, the two split doses registered higher N uptake. The nitrogen uptake by both grain and straw was conspicuously higher in three and two split doses of potassium.

Conclusion: The split applications tested in this investigation influenced the available N status in soil. Almost in all the stages, three split applications retained more available N in soil. This implies the positive interaction of potassium with nitrogen.