Chilli (Capsicum spp.) is essential to Sri Lanka’s agricultural economy and household nutrition. However, the sector faces ongoing challenges, including low dry chilli productivity, pest and disease pressures particularly from the chilli leaf curl complex and a heavy dependence on expensive imported dried chillies. To tackle these issues, the Sri Lankan Department of Agriculture (DOA) and the Field Crops Research & D evelopment I nstitute ( FCRDI) developed MICH Hy1, a high-yielding, p est-resistant hybrid chilli variety suited to local conditions. From 2019 to 2021, the ‘KOPIA Chilli Project’ initiated a participatory hybrid seed production initiative in Kothmale, involving farmers in a decentralized seed system utilizing insect-proof net houses and capacity-building programs. This collaborative approach has successfully enhanced seed quality, improved farmers’ incomes, increased the availability of affordable hybrid seeds, and reduced reliance on imported varieties. The initiative highlights the potential of farmer-led hybrid seed systems to strengthen national seed security, empower rural communities, and promote sustainable chilli cultivation in Sri Lanka.

This study presents, for the first time, a piezoelectric nanogenerators (PENG) model based on the nitrogen-doped carbon nanotubes (N-CNTs) array and demonstrates the ability of N-CNT to convert external oscillations into electrical energy. Molybdenum was proved to be a preferred material for the upper electrode due to its high corrosion resistance and the formation of ohmic contact at the interface with N-CNT. It was shown the operation of the PENG model in constant and pulsed modes. It was found that the output voltage of the PENG model increased linearly from 3 to 60 mV with an increase in the amplitude of the external mechanical influence from 3.5 to 95 μm and decreased from 54 to 26 mV with an increase in the frequency of external influence from 15 to 120 Hz due to an excess of the natural resonant frequency of the nanotubes. The experiments demonstrated that the power density of the N-CNT-based PENG model reached 12.63 μV/cm2. It was exhibited that the PENG model can be used not only as a nanogenerator for autonomous power supply of wearable electronic devices, but also as a highly sensitive deformation sensor. In addition, the clamping force of the upper electrode determines the frequency range of the PENG model. The obtained results open wide opportunities for practical application of vertically aligned N-CNTs for autonomous power supply of wearable electronic devices.

Sesbania bispinosa (Jacq.) W. Wight is a weedy green manure plant of the family Fabaceae. The legume plants play a major role in nitrogen fixation and soil fertility while biochar plays a significant role in environmental remediation. The present study has aimed to convert S. bispinosa in combination with cow dung (1:1, v/v) into enriched vermicompost through the amendment of different concentrations of activated Prosopis wood biochar. Totally 10 treatments were maintained: VSB1- VSB5 and SB1-SB5 with and without earthworms, respectively. The treatments were maintained under controlled environmental conditions in triplicate till 28 days. The initial and final samples of the treatments with and without earthworms were analyzed for physicochemical characteristics, FTIR analysis and phytotoxicity assay. The pH, total organic carbon, C/N ratio and C/P ratio showed a declining trend while the nutrients, total nitrogen, phosphorus, potassium, calcium and sodium contents displayed increment towards the progression of vermicomposting. A total nitrogen content of 2.78% was recorded in vermicompost amended with 3% biochar followed by 2.61% in 2% biochar amendment. The functional group changes from initial substrates to final vermicompost inferred through FTIR analysis denote the decomposition of complex organic materials into simple forms. The lowest C/N ratio (19.06) with a higher germination index (102.85%) of Vigna mungo (black gram) seeds were observed in the vermicompost of S. bispinosa + cow dung substrates amended with 3% biochar within a very short period of time (28 days). Hence, the use of biochar at a 3% level is recommended for the vermiconversion of green manure biomass to obtain nutrient-amplified vermicompost. It is also beneficial to use 2% biochar in vermicomposting, however, 3% biochar amendment is highly beneficial and a better choice from a vermicompost quality perspective.