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The modification of secondary metabolites is crucial to the function of metabolites in tea (Camellia sinensis L.). The arabinan deficient (ARAD) encodes an arabinosyltransferase and is involved in the arabinan biosynthesis pathway. Two full-length sequences of CsARADs were cloned and obtained from tea plants through the rapid amplification of cDNA ends and named CsARAD1 and CsARAD2. CsARAD1 and CsARAD2 are predicted to be 2 membrane proteins containing N-glycosylation, phosphorylation, and N-myristoylation sites and are 2 homologs of the glycosyltransferases (GT) 47 family, according to various bioinformatic analyses. CsARADs showed higher transcription levels in nonlignified tissues (e.g., buds and young leaves) than in old leaves and stems. CsARADs also exhibited the highest expression level in autumn, indicating that CsARAD regulation is affected by environmental factors. The transcript levels of CsARADs were changed after various abiotic stress treatments, and CsARAD1 and CsARAD2 displayed different regulation patterns in temperature stress, saline, and drought-like conditions. CsARAD1 and CsARAD2 were both significantly downregulated after tea seedlings were treated with an ethylene precursor and abscisic acid. In addition, CsARAD2 was downregulated after being treated with methyl jasmonate and gibberellin. Collectively, our findings on the function of arabinosyltransferase serve as a basis for further research and breeding applications.

Edamame (Glycine max (L.) Merr.) is an important economic crop worldwide and is a good source of protein and nutrients. Kaohsiung No. 9 (KH9), Kaohsiung No. 11 (KH11), and Xiang-Ji (XJ) are three major edamame cultivars planted in Taiwan. Edamame has high water requirements in all development stages. Insufficient irrigation causes aborted blossoms, small pods, and shriveled beans, thus greatly reducing the yield. We examined the three aforementioned cultivars in drought conditions during the blooming period. The results revealed that drought stress decreased the yield in all three cultivars; however, XJ and KH11 showed better drought resistant ability than KH9 did. The reduction of the qualification rate and the dry weight of qualified pods by drought stress in XJ, KH9 and KH11 was 23%, 33%, 21% and 32%, 62%, and 44%, respectively. The quantitative reverse-transcription polymerase chain reaction results indicated that genes involved in the abscisic acid (ABA) biosynthesis, ABA-dependent, and ABA-independent pathways were upregulated by drought stress in KH11, which may explain why KH11 produced higher yields than KH9 after drought treatment. We determined that drought-related signaling transduction differed among these edamame cultivars, resulting in different drought tolerance.