The Influence of N-P-K Fertilizer Rates and Cropping Systems on Root Biomass and Some Root Morphological Variables of Sweet Corn and Vegetable Soybean

Abstmct: A field experrment using L2>:0.5.0.5 rn rhizoboxes u'ith 280 kg soil was carried out to investigate the eft'ect of tlree N-P-K t'ertriizer rates (,50.100 ald 1 5t10.,6 of the recommended fertilizer rate) and cropplng systems (rrrono-crop com or soybean, rntercrop com and sol,bean without root separation, with plastic and wrth geotextile root separation) on root biomass, volume surface area and total root length, Mono-crop com and intercropped com under plastic sheet root separation had significantly higher total root length than intercr opped com wrthor.rtroot separation and with geotextile root separation, but soybean lugher root vohune r,vas notrced in intercropped soybea:r lvithout root separation ancl ,,vith geotextrle root separaton.Increasing i'etility level from -509,'o of recommencled rate @I'R) to 1 00 and 1 50% RFR sigruficantly increased root dry u'eight of com and soybearl as lvell as root volume, surface alea and total root length of com.In soybean increasing fertilig' level from 50 to 1 0096 RFR urcreased total root length and root surface area, but fr,ulher increase to 1 50% of recommended rate decreased both var-iables.