Tanggap tanaman kedelai terhadap inokulasi Rhizobium daD asam indol asetat (IAA) pada ultisol Darmaga

Abstract

Some of rhizobacteria have been known to stimulate the growth of some crops through their fitohormon ~' (IAA =indoleacetic acid).. Those rhizobacteria can stimulate the developmenot f epidermisc ellsf ormation at root hair ;~ ' sitea ndi ncreaseth e infections itest o increaseth en odulationa ndN .?fzxationT.h ea imso f thiss tudyw eret o studyt he ~!i effect of Rhizobium strains inoculation and indole acetic acid (IAA) application on crop growth, root nodulation. and :!h N, P uptake of soybean on the Ultisols. The greenhouse experiment used Completely Randomize Design (CRD) with ;:~t;, four replications. The treatments were: I) Without inoculation (blank), 2) 100 ppm N application, 3) 0.4 ppm IAA '~~;c application, 4) Inoculation of Rhizobium 1004 (106),5) Inoculation of Rhizobium 1004 (I if) +IAA, 6) Inoculation of ~'!: Rhizobium RD-20 (104), 7) Inoculation of Rhizobium RD-20 (106), 8) Inoculation of Rhizobium SNI-2 (106). 9) l,':fi~ Inoculation of Rhizobium SNI-2 106+IAA. Result of the experiment indicated that inoculation of Rhizobium and IAA ..,.,~~" application increased crop growth, nodulation, and nutrient uptake of soybean. Inoculation of Rhizobium I 004(106). ~%;. RD-20(104)R, D-20(I06),S NI-2(I06), andIAA 0.4p pm increasedd ry weight of crop by 33.5%,37.8,17.3%,35.1%,a nd ~l; 3.8% respectively compared to blank. Application ofIAA at Rhizobium inoculation treatment ofSNI-2(106) and :iiJ~ 1004(106i)n creasedd ry nodule weight on soybean4 0.9%a ,nd5 5.7 % respel!tivelyc omparedt o without IAA application.