kyin htwe
Agronomy and Soil Science, University of New England, Armidale NSW, Australia
Title: Applied P contribution to nutrient recovery and root responses by P placement with different K anion sources on vigna radiata L in sandy soil using 32P isotope labelling technique
Biography
Biography: kyin htwe
Abstract
Nutrient uptake of mungbean can be improved by localised phosphorus (P) with and without potassium (K) application. Research on co-application of P and K has produce variable results and the correlation between nutrient uptake and root growth of mungbean is still ambiguous. Therefore, experiment was conducted to examine the comparative effects of localized application of P (labelling isotopic 32P to P fertilizer) and different sources of K (KNO3, KCl, K2SO4 and KH2PO4) on root growth, nutrient uptake and P recovery, and biomass of mungbean (Vigna radiata L.) on a sandy soil with low P and K status. Factors contributing to these variable results such as soil moisture, pH in the rhizosphere soil and fertilised zone with P and K sources are being investigated to support the consistency of results in such applications. Although P and K supply was not significantly influenced on root proliferation, localized supply of P and K had prominent increment on root growth particularly fine and medium root length within the range of 14-28% of mungbean roots being allocated in the PK rich zone (Table 1). The increased nutrient uptake and plant growth (shoot and root) was related to the higher proportion of root length in the localized PK enriched zone and the plant roots in the patch accounted for a high P, K and S uptake in the shoots (Figure 1). P recovery was not significantly different between single P and PK co-location. The only significant effect was higher shoot and root yield and higher fertilizer P and K recovery in the P+KS shallow (potassium sulphate used as K source) compared with the zero K treatment. The results generally indicated that root growth in PK patches contributed more to mungbean growth and nutrient uptake which somewhat allied with pH deviations in the rhizosphere.