EFFECT OF IRON DEFICIENCY ON ROOT FERRIC CHELATE REDUCTASE,PROTON EXTRUSION,BIOMASS PRODUCTION AND MINERAL ABSORPTION OF CITRUS ROOT STOCK ORANGE JASMINE (MURRAYA EXOTICA L.)

Three-week iron (Fe) deficiency stress experiments were conducted using two citrus root stocks, Fe-deficiency tolerant Orange Jasmine (OJ, Murraya exotica L.) and the sensitive Flying Dragon [FD, Poncirus trifoliata var. monstrosa (T. Ito) Swingle]. Root ferric chelate reductase activity and proton extrusion increased in OJ between 12 and 18 d of stress, whereas there was no change in FD. Dry weight of OJ roots increased in contrast to FD which decreased. The Mn content in OJ remained the same even under Fe stress. Zn content in OJ roots doubled while that of FD increased 4-folds. The shoot/root Fe accumulation ratio increased in OJ while it decreased in FD. OJ apparently has mechanisms for increasing root biomass, controlling Fe reutilization and regulating manganese (Mn) and zinc (Zn) absorption in response to Fe deficiency. These mechanisms could help maintain homeostasis under heavy metal stress, which would be useful for improved growth of economically important citrus species.     

Impact of transgenic sugarcane overexpressing SoSPS1 gene on bacterial diversity,enzyme activity and minerals content in soil rhizosphere

Journal of Crop Science and Biotechnology - The transgenic sugarcane overexpressing SoSPS1 gene increased sugar content which may alter the root exudation that interact with soil rhizosphere...     

Impact of biochar on mineralisation of C and N from soil and willow litter and its relationship with microbial community biomass and structure

Using a laboratory experiment, we investigated the effect of applying willow biochar to short rotation coppice soil on C and N dynamics and microbial biomass and community composition, in the presence and absence of willow litter. Application of biochar at a rate of 0.5 % had no effect on net CO₂ mineralisation in the presence or absence of litter. However at a rate of 2 %, net CO₂ mineralisation was reduced by 10 and 20 % over a 90-day period in the absence and presence of litter respectively. Biochar reduced N mineralisation when applied at both 0.5 and 2 % concentrations. pH was increased by application of 2 % biochar to soil. Phospholipid fatty acid analysis demonstrated that both concentrations of biochar affected microbial community composition, although the effect of biochar was not as great as the effect of time or litter application in shaping community structure. In particular, the amount of bacterial biomass was increased by biochar application to soil, and there was evidence for increased abundance of Gram-negative bacteria and actinobacteria following biochar application. The data is discussed in the context of microbial mechanisms underlying impacts of biochar on C cycling in soil, and the coupling of C and N cycles following amendment of soil with biochar.     

The Importance of Social Learning for the Development of Community Based Forest Management in Indonesia: The Case of Community Forestry in Lampung Province

Community-based forest management is unlikely to be sustainable without a process of social learning between the internal and external actors. This situation is evident in West Lampung District in Lampung Province, Indonesia. This research assessed the processes and outcomes of social learning within three villages (i.e. Villages A, B and C) in West Lampung District that were engaged in a community forestry (CF) program. The data was gathered through questionnaire and interview which then analyzed with Likert Scale. The CF program outcomes were different in each village. Village A had the highest scores for facilitation, egalitarian atmosphere, repeated meetings, and diverse participation. This has resulted in a high level of community involvement in the CF program. In particular, the high level of facilitation by external actors such as training programs, and marketing information and funding has resulted in the community having a good knowledge of CF and the associated socioeconomic development programs available to them. Village B has highest score for multiple sources of knowledge variable. Due to the existing egalitarian atmosphere, each stakeholder in Village A can openly express their opinion without any hesitation, particularly between men and women. Meanwhile, the other sub variables of existing egalitarian atmosphere were scored the same for Village A, B, and C, such as the balances between old and young people as well as rich and poor people. In general, the implemented social learning has a greater positive effect on the livelihoods of CF group members in Village A compared to Villages B and C.