The Para rubber tree (Hevea brasiliensis) is an economically important tropical tree species that produces natural rubber, an essential industrial raw material. Here we present a high-quality genome assembly of this species (1.37 Gb, scaffold N50 = 1.28 Mb) that covers 93.8% of the genome (1.47 Gb) and harbours 43,792 predicted protein-coding genes. A striking expansion of the REF/SRPP (rubber elongation factor/small rubber particle protein) gene family and its divergence into several laticifer-specific isoforms seem crucial for rubber biosynthesis. The REF/SRPP family has isoforms with sizes similar to or larger than SRPP1 (204 amino acids) in 17 other plants examined, but no isoforms with similar sizes to REF1 (138 amino acids), the predominant molecular variant. A pivotal point in Hevea evolution was the emergence of REF1, which is located on the surface of large rubber particles that account for 93% of rubber in the latex (despite constituting only 6% of total rubber particles, large and small). The stringent control of ethylene synthesis under active ethylene signalling and response in laticifers resolves a longstanding mystery of ethylene stimulation in rubber production. Our study, which includes the re-sequencing of five other Hevea cultivars and extensive RNA-seq data, provides a valuable resource for functional genomics and tools for breeding elite Hevea cultivars.

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A novel wireless passive temperature sensor based on a reflective patch is demonstrated up to 1050 o C herein. This reflective patch acts as a patch resonator (temperature sensor) and an integrated antenna at the same time. The temperature sensing mechanism is the monotonic increase of the dielectric constant of alumina versus temperature, which reduces the resonant frequency of a patch resonator formed on such an alumina substrate. By properly designing the shape and dimensions of the patch, it can also act as a transmit/receive antenna for wireless passive sensing. Therefore, temperatures can be wirelessly sensed by measuring the resonant frequency of the temperature sensor using an interrogation antenna. This temperature sensor uses robust alumina and platinum materials for high-temperature applications. In addition, this wireless passive temperature sensor is simple in mechanical structure and low in profile, with the potential to be in conformal shape. A temperature sensor using this reflective patch was designed, fabricated and tested from 50 to 1050 o C in ambient. The resonant frequency of the sensor decreases from 5.07 to 4.58 GHz, which corresponds to a dielectric constant change from 9.7 to 11.4 for the alumina substrate. The temperature measurement sensitivity is found to be 0.58 MHz/ o C at 1050 o C. Being wireless, passive, planar and low profile, the proposed high-temperature sensor can be used for various harsh-environment applications.

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A new approach to integrate high‐quality (Q)‐factor three‐dimensional vertical cavity filters with patch antennas into a single unit is presented. This integrated filter/antenna system exhibits small footprint, high efficiency and enhanced bandwidth. The patch antenna is designed to provide an additional transmission pole for the filtering function and works as a highly efficient radiator. In addition, this integrated patch antenna with a filter can achieve a bandwidth larger than that of a standalone patch antenna with the same geometry. A prototype three‐pole Chebyshev filter/antenna is demonstrated at X band. The centre frequency and fractional bandwidth of the filter/antenna system are 10.27 GHz and 8.7%, respectively. Owing to the high Q factor ( ∼650) of the cavity resonator and near loss‐less transition between the antenna and filter, the overall efficiency of the filter/antenna system is simulated to be as high as 91.8%. The reduced footprint, enhanced bandwidth and low‐loss performance of these integrated filter/antenna systems make them particularly useful for phased array applications. Prototypes of the filter/antenna systems as well as a filter/antenna array are fabricated and measured. An excellent agreement between the simulated and measured results is observed.

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Rubber trees are economically important tropical tree species and the major source of natural rubber, which is an essential industrial material. This tropical perennial tree is susceptible to cold stress and other abiotic stresses, especially in the marginal northern tropics. Recent years, the genome sequencing and RNA-seq projects produced huge amount of sequence data, which greatly facilitated the functional genomics study. However, the characterization of individual functional gene is in urgent demands, especially for those involved in stress resistance. Here we identified and characterized the rubber tree gene ErbB-3 binding protein 1, which undergoes changes in expression in response to cold, drought stress and ABA treatment. HbEBP1 overexpression (OE) in Arabidopsis increased organ size, facilitated root growth and increased adult leaf number by delaying the vegetative-to-reproductive transition. In addition, HbEBP1 OE enhanced the resistance of the Arabidopsis plants to freezing and drought stress, demonstrating that this gene participates in the regulation of abiotic stress resistance. RD29a, RD22 and CYCD3;1 expression was also greatly enhanced by HbEBP1 OE, which explains its regulatory roles in organ size and stress resistance. The regulation of drought stress resistance is a novel function identified in plant EBP1 genes, which expands our understanding of the roles of EBP1 gene in response to the environment. Our results provide information that may lead to the use of HbEBP1 in genetically engineered crops to increase both biomass and abiotic stress resistance.