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This study aimed to screen and characterize halotolerant bacterial isolates, which could enhance plant growth performance in saline soil. Halotolerant bacteria was isolated from weeds rhizosphere grown in saline soil of coastal agricultural land located at Brondong District, Lamongan Regency, East Java Province, Indonesia. This research was conducted from June to September 2018. Seven bacterial isolates can grow in a Nutrient Agar medium containing 10% of NaCl, suggesting that these bacteria were halotolerant. Furthermore, all bacterial isolates were shown to produce indol acetic acid (IAA) and do not induce a hypersensitive response when infiltrated into tobacco leaves. These results explain that these bacteria had potency as plant growth-promoting rhizobacteria (PGPR) and were not tend to be the plant pathogen. The growth of seedlings when inoculated in cucumber seed grown in saline media were higher than those in control. This result suggests that the halotolerant bacteria can enhance the development of cucumber seedlings in saline stress conditions. Three potential halotolerant bacteria i.e., SN22, SN23, SN26 were selected and molecularly identified as Bacillus megaterium, Bacillus sp., and B. megaterium, respectively. [ABSTRACT FROM AUTHOR]

Complex rice systems (CRS) are polycultures in which rice is grown together with one or more plant or animal species using combined methods of practices from indigenous knowledge and modern science in augmenting ecological processes to foster ecosystem services in rice agroecosystems. However, their implementation faces challenges due to farmers' knowledge gaps, high capital outlay and labour shortages. This study aims to link types of rice farming and farmer perceptions to facilitate recommendations to scale up CRS. We constructed a farm typology based on a survey of 111 farm households and aggregated cognitive maps (ACMs) based on fuzzy cognitive maps developed in focus group discussions in Malang and Lamongan, East Java Province, Indonesia. The farm typology classified farm households into three types: (a) small farms with high inputs of agrochemicals (SH, n = 29) which were all identified in Malang; (b) medium-size farms with high input intensity of agrochemicals (MH, n = 43), distributed across Malang and Lamongan; and (c) medium-size farms with low inputs of agrochemicals (ML, n = 39), all detected in Lamongan. ACMs revealed the differences in farmer group's perceptions on farm input-output relations, agroecosystems processes and CRS component interactions. SH and MH farmers prioritised economic benefits over ecosystem services and crop-livestock components. SH farmers were locked into high-input and high-output systems, while MH farmers failed to obtain high output despite high input use. Intervention schemes could be developed such as thorough training on economics for SH farmers and efficient use and on-farm production of fertilisers for MH farmers. Meanwhile, with the majority of ML farmers having adopted CRS, their priorities were more evenly distributed across all components, implying their more holistic understanding of the interacted components. However, technical assistance on agronomic, post-harvest management and marketing were still considered to be needed to ensure a long-term sustainability of CRS practices by ML farmers. Combining farm typology and fuzzy cognitive mapping could facilitate a comprehensive understanding of farming system types, their characteristics and farmer perceptions as a key to formulate appropriate interventions for a specific farm type. Therefore, these methodological approaches could provide guidance to accelerate transitions toward complex agroecosystems. [Display omitted] • Farmers' knowledge gaps are the main challenge in complex rice systems (CRS) implementations. • Farm typology classified rice farming systems and aggregated cognitive maps captured farmer group perceptions. • The linkage between rice farming types and their farmer's perceptions were used to assess intervention schemes for CRS implementations. • Intervention schemes recommended different trainings and support based on the specific farm type. • These methodological approaches provide transition guidance toward complex agroecosystems. [ABSTRACT FROM AUTHOR]