Strigolactones (SLs) represent an important new plant hormone class marked by their multifunctional roles in plants and rhizosphere interactions, which stimulate hyphal branching in arbuscular mycorrhizal fungi (AMF) and seed germination of root parasitic plants. SLs have been broadly implicated in regulating root growth, shoot architecture, leaf senescence, nodulation, and legume–symbionts interaction, as well as a response to various external stimuli, such as abiotic and biotic stresses. These functional properties of SLs enable the genetic engineering of crop plants to improve crop yield and productivity. In this review, the conservation and divergence of SL pathways and its biological processes in multiple plant species have been extensively discussed with a particular emphasis on its interactions with other different phytohormones. These interactions may shed further light on the regulatory networks underlying plant growth, development, and stress responses, ultimately providing certain strategies for promoting crop yield and productivity with the challenges of global climate and environmental changes.

The inorganic selenium is absorbed and utilized inefficiently, and the range between toxicity and demand is narrow, so the application is strictly limited. Selenium nanoparticles have higher bioactivity and biosafety properties, including increased antioxidant and anticancer properties. Thus, producing and applying eco-friendly, non-toxic selenium nanoparticles in feed additives is crucial. Bacillus paralicheniformis Y4 was investigated for its potential ability to produce selenium nanoparticles and the activity of carboxymethyl cellulases. The selenium nanoparticles were characterized using zeta potential analyses, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Additionally, evaluations of the anti-α-glucosidase activity and the antioxidant activity of the selenium nanoparticles and the ethyl acetate extracts of Y4 were conducted. B. paralicheniformis Y4 exhibited high selenite tolerance of 400 mM and the selenium nanoparticles had an average particle size of 80 nm with a zeta potential value of −35.8 mV at a pH of 7.0, suggesting that the particles are relatively stable against aggregation. After 72 h of incubation with 5 mM selenite, B. paralicheniformis Y4 was able to reduce it by 76.4%, yielding red spherical bio-derived selenium nanoparticles and increasing the carboxymethyl cellulase activity by 1.49 times to 8.96 U/mL. For the first time, this study reports that the carboxymethyl cellulase activity of Bacillus paralicheniforis was greatly enhanced by selenite. The results also indicated that B. paralicheniformis Y4 could be capable of ecologically removing selenite from contaminated sites and has great potential for producing selenium nanoparticles as feed additives to enhance the added value of agricultural products.

Yellow leaf disease (YLD), caused by the areca palm yellow leaf phytoplasma (APYL), poses a significant threat to the sustainability of the areca palm industry. Timely and accurate detection is essential for effectively diagnosing and managing this disease. This study developed a novel nested PCR system using primers specifically designed from conserved regions of the phytoplasma 16S rDNA sequence to overcome limitations such as false positives often associated with universal nested PCR primers. The resulting primer pairs HNP-1F/HNP-1R (outer) and HNP-2F/HNP-2R (inner) consistently amplified a distinct 429 bp fragment from APYL strains belonging to the 16SrI and 16SrII groups. The detection sensitivity reached 7.5 × 10⁻⁷ ng/μL for 16SrI and 4 × 10⁻⁷ ng/μL for 16SrII. Field validation using leaf samples from symptomatic areca palms confirmed the high specificity and reliability of the new primers in detecting APYL. Compared to conventional universal primers (P1/P7 and R16mF2/R16mR1), this newly developed nested PCR system demonstrated higher specificity, sensitivity, and speed, making it a valuable tool for the early diagnosis and management of YLD in areca palms.

Yellow leaf disease (YLD), caused by areca palm yellow leaf phytoplasma (AYLP), is a devastating disease that severely impacts the sustainable development of the areca palm industry. Efficient and accurate detection methods are considered crucial for the diagnosis and management of YLD. To address issues like false positive results using universal nested PCR primers, this study designed specific outer and internal primers based on the conserved regions of the 16S rDNA sequence of phytoplasmas, resulting in a nested PCR primer set, HNP-1F/HNP-1R and HNP-2F/HNP-2R. This set consistently amplified a single specific target band of 429 bp from 16SrI and 16SrII groups of AYLP. The sensitivity threshold for the 16SrI group of AYLP was 7.5×10-7 ng/μL, while that for the 16SrII group of AYLP was 4 ×10-3 ng/μL. To verify and evaluate the efficiency, the developed nested PCR system was used to detect leaf samples collected from trees showing leaf yellowing symptoms in areca palm plantations, and the results showed that the primer set could specifically detect AYLP. This primer set is characterized by rapid and accurate detection, high specificity, and high sensitivity compared to the traditional universal primer set of P1/P7 and R16mF2/R16mR1 or R16mF2/R16mR1 and R16mF2n/R2, providing a scientific basis for the specific diagnosis and early control of yellow leaf disease of areca palm.