Philippine Rice Research Institute

The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith), has become a major constraint to sweet corn (Zea mays subsp. saccharata S.) production in Indonesia, highlighting the urgent need for sustainable Integrated Pest Management (IPM) strategies. This study evaluated the field performance of an integrated IPM package combining sweet corn and turmeric (Curcuma longa L.) intercropping with foliar eco-enzyme application compared with a sweet corn monoculture. Because the experiment involved two primary treatments, the study aimed to demonstrate the overall effectiveness of the integrated system rather than isolate the individual contributions of each component. Field trials were conducted from April to September 2025 under comparable agroecological conditions with five replicated plots per treatment. The integrated system significantly suppressed pest populations; specifically, by 6 weeks after planting (WAP), plant infestation reached 88

Rice (Oryza sativa L.) is a major staple crop, feeding over half of the global population. However, its production is often compromised by biotic stressors, particularly fungal and bacterial diseases, which can cause severe yield losses. While conventional chemical controls offer short-term effectiveness, they also lead to environmental degradation, pathogen resistance, and health risks for farmers and consumers. To address these challenges, plant growth-promoting fungi (PGPF) have emerged as a sustainable alternative for rice disease management. PGPF enhance plant immunity, outcompete pathogens, and promote growth through mechanisms such as competition for nutrients and space, mycoparasitism, antibiosis, and induced systemic resistance. This review examines the mechanisms by which PGPF suppress rice pathogens, highlights their environmental and economic benefits, and addresses challenges to their practical application. Further research is essential to enable the widespread adoption of PGPF-based strategies in rice production systems.

Rice (Oryza sativa) is a global staple threatened by diseases such as bacterial leaf blight (Xanthomonas oryzae pv. oryzae), sheath blight (Rhizoctonia solani), blast (Magnaporthe oryzae), and panicle blight (Burkholderia glumae and B. gladioli), which cause significant yield losses. Conventional agrochemical use has raised environmental and health concerns, prompting a shift toward sustainable alternatives. This review examines the role of plant growth-promoting rhizobacteria (PGPR) as promising biocontrol agents. PGPR enhance rice health and suppress pathogens through a variety of direct and indirect mechanisms. Direct actions include the production of antibiotics and lytic enzymes, competition for nutrients, and the synthesis of phytohormones and siderophores. Indirectly, PGPR activate induced systemic resistance (ISR), priming the plant's immune system via jasmonic acid (JA) and ethylene (ET) signaling pathways. While empirical studies confirm that PGPR can improve plant growth, enhance stress tolerance, and reduce disease severity, inconsistent field performance remains a major challenge. This variability is often due to complex strain-environment interactions, inconsistent root colonization, and the lack of robust formulations. To overcome these limitations, future research should focus on utilizing 'omics-based approaches to better understand PGPR-microbe-plant interactions. Additionally, there is a need to develop more stable biostimulant consortia and to fully integrate these biological agents into climate-smart agricultural systems. This review synthesizes current knowledge on PGPR-mediated disease management and highlights their potential to improve crop resilience and productivity while promoting eco-friendly farming practices.

Analysis of early morphophysiological traits revealed the competitive dominance of weedy rice (WR) biotypes (SR 1, ILO 13, ILO 17) over the cultivated rice variety NSIC Rc 222. Using the root box method, mono- and mixed cultures were grown under 2 fertilizer levels: 0 NPK and full NPK (120-60-60 kg ha−1). WR biotypes exhibited early vigor, characterized by greater plant height, tiller numbers, and shoot and root dry weights—traits that were further enhanced by fertilizer application. WR biotypes also maintained significantly higher total root lengths, total lateral root lengths, and nodal root counts. Notably, ILO 17 displayed a high root branching index (~4.0 to 4.8 lateral roots per cm nodal root), forming a dense fine-root mesh that suppressed Rc 222 root development. Although fertilizer × genotype interactions were not significant for major root traits, the stable root architecture of WR translated into a higher Competitive Index and greater dry matter accumulation. Under 0 NPK, WR competition, particularly from the spatially aggressive root system of ILO 17, compromised the crop’s photosynthetic capacity, causing a marked decline in net photosynthetic rate alongside increased intercellular CO2 concentration. Conversely, WR biotypes showed high resilience, tightly coupling stomatal conductance and transpiration (r = 0.959) to sustain photosynthesis. While full NPK inputs partially mitigated this suppression and allowed Rc 222 to recover leaf area and photosynthetic capacity, the crop remained vulnerable. These findings demonstrate that WR outcompetes cultivated rice through early shoot vigor and aggressive root proliferation, highlighting the critical need for early seedling management strategies to prevent crop yield losses.

Understanding the effect of irrigation is critical for ensuring future food security in the Philippines. While previous analysis has focused on national-level irrigation conversion targets to achieve 98% rice self-sufficiency, this study offers a more comprehensive assessment. We integrated 11,003 provincial-level rice statistics (5211 for the dry season; 5792 for the wet season) to quantify differences in the yield sensitivity of irrigated and rainfed rice to climate. Furthermore, we projected the effect of irrigation conversion under future climate conditions. Our findings indicate that converting rainfed rice to irrigated presents substantial potential to offset negative climate impacts on rice yields in the future. However, despite these gains, the rice self-sufficiency ratio is projected to remain below 87%, suggesting that adverse climate impacts may constrain the adaptive limits of irrigation conversion. These results imply that irrigation conversion should be treated as one component of a broader adaptation strategy rather than a standalone solution to safeguard food security in the Philippines.