POTENTIAL OF Rhizobium sp. I 3 AND Agrobacterium sp. I 3 7 IN FORMATION OF ROOT NODULES AND STIMULATING GROWTH OF Arachis hypogaea L.

ABSTRACT Rhizobium sp.I 3 and Agrobacterium sp.I 37 bacteria can increase plant growth and have the potential to become a member of the plant growth-promoting rhizobacteria (PGPR). Rhizobium bacteria can increase nitrogen availability for legume plants by forming nodules. Rhizobium sp. and Agrobacterium sp. are closely related; therefore, we speculated that Agrobacterium sp. can also form nodules. The study was based on completely randomized design and conducted from July 2019 to December 2019 in laboratories of the Faculty of Agriculture, Universitas Sebelas Maret, Central Java, Indonesia. The study included 11 different treatments of biofertilizer: P0, P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, and P11 with each treatment in triplicate to obtain 36 experimental units. The results showed that the control treatment (P0) had 0 nodules, 8.26 g biomass, and 3.54% tissue nitrogen uptake. The three best treatments were in the order: P4 ( Rhizobium biofertilizer) with 174.3 root nodules, 14.77% tissue nitrogen (four times higher than that of control), and 24.05 g biomass; P8 ( Rhizobium biofertilizer) with 167 nodules, 12.42% tissue nitrogen (three times higher than that of control), and 19.26 g biomass; P5 ( Agrobacterium biofertilizer) with 146.6 root nodules, 13.15% tissue nitrogen (three times higher than that of control), and 16 g biomass.

摘要：根瘤菌属（Rhizobium）菌株I 3与农杆菌属（Agrobacterium）菌株I 37可促进植物生长，具备成为植物促生根际菌（PGPR）的潜力。根瘤菌可通过形成根瘤，提升豆科植物的氮素有效性。根瘤菌属与农杆菌属亲缘关系紧密，因此本研究推测农杆菌属菌株同样可形成根瘤。
本研究采用完全随机设计，于2019年7月至2019年12月在印度尼西亚中爪哇省塞贝拉斯·马雷特大学农学院实验室开展。实验共设置11组不同生物肥料处理，即P0、P1、P2、P3、P4、P5、P6、P7、P8、P9、P10及P11，每组处理设置三次重复，共计36个实验单元。
结果显示，对照组（P0）的根瘤数量为0，生物量为8.26 g，组织氮吸收量为3.54%。表现最优的三组处理依次为：P4（根瘤菌生物肥料），其根瘤数量达174.3个，组织氮含量为14.77%（为对照组的4倍），生物量为24.05 g；P8（根瘤菌生物肥料），根瘤数量167个，组织氮含量12.42%（为对照组的3倍），生物量19.26 g；P5（农杆菌生物肥料），根瘤数量146.6个，组织氮含量13.15%（为对照组的3倍），生物量16 g。