Shikui Song

Auxin is a crucial hormone that regulates various aspects of plant growth and development. It exerts its effects through multiple signaling pathways, including the TIR1/AFB-based transcriptional regulation in the nucleus. However, the specific role of auxin receptors in determining developmental features in the strawberry (Fragaria vesca) remains unclear. Our research has identified FveAFB5, a potential auxin receptor, as a key player in the development and auxin responses of woodland strawberry diploid variety Hawaii 4. FveAFB5 positively influences lateral root development, plant height, and fruit development, while negatively regulating shoot branching. Moreover, the mutation of FveAFB5 confers strong resistance to the auxinic herbicide picloram, compared to dicamba and quinclorac. Transcriptome analysis suggests that FveAFB5 may initiate auxin and abscisic acid signaling to inhibit growth in response to picloram. Therefore, FveAFB5 likely acts as an auxin receptor involved in regulating multiple processes related to strawberry growth and development.

Quinoa (Chenopodium quinoa Willd.) is poised to be a global life changer with its ability to adapt to a wide range of abiotic stresses and as a highly nutritious and sustainable food source. A trial on screening of salt tolerance was conducted at the germination and seedling stages of 69 quinoa genotypes in different concentrations of NaCl 0 (CK), 100, 200, 300, 400, and 500 mM for 21 days in the MS/2 mixture. This results in 16 genotypes with >50% germination at 400 mM NaCl. These were reassessed in germination indices and relative growth. Results indicated that Chadmo had the highest germinability of 97% and 32.76% relative height among the 16 genotypes. Considering the germination indices, Chadmo had significantly different values (3.05±0.19 day^-1) in mean germination time, coefficient of variation of the germination time (38.76±1.97%), the velocity of germination (0.23±0.01 day^-1), the uncertainty of germination (0.54±0.08 bit), synchrony of germination (0.42±0.05 and Timson’s index (48.89) with significant differences (P<0.05) among the genotypes. Moreover, Chadmo had the highest membrane stability index (MSI) (60.03±11.84) at 400 mM NaCl and the least relative change between the CK and 400 mM NaCl with 30.87±2.01%. Assessing the stress inhibitory effect of the 16 genotypes, Chadmo had the least relative difference between the CK and 400 mM NaCl with shoot length of 34.34%, root length of 25.57%, fresh weight of 22.05%, dry weight of 3.62% and moisture content of 1.99% with Tukey analyses identifying significant differences (p<0.05). To select the salt-sensitive genotype, an assessment was done on five genotypes that exhibited the least germination at 200 mM NaCl. Kankolla had the least germinability with 12 and 4% at 100 and 200 mM NaCl, respectively. Considering all these parameters, Chadmo and Kankolla were selected as salt-tolerant and salt-sensitive for further analyses.

Quinoa (C. quinoa) is considered a gluten-free food with abundant nutrients and high tolerance to multiple abiotic stresses, which is the potential to become a major crop in future. Genetic manipulation will provide powerful tools to investigate the function and mechanism of those important genes in the regulation of quinoa development and stress responses, and further improve the quinoa in the field. However, the efficient plant transformation system for quinoa has not been well developed yet. Here, we established two rapid and efficient transformation systems for quinoa by using hairy roots and agroinfiltration of leaves, which provide useful tools for quick analysis of gene function. Hairy roots were obtained from three types of explants: cotyledon-nod with hypocotyl, cotyledon itself, and hypocotyl pieces. Interestingly, explants of cotyledon-nod with hypocotyl showed the highest transformation efficiency at 67.9%, and cotyledon displayed medium efficiency at 42.2%, while hypocotyl explants with the lowest at 31.6%. We also obtained transgenic quinoa roots successfully in-vivo, which showed low efficiency but provides a potential method to test gene functions in live plants. By using young leaves for agroinfiltration, direct injection showed a better transgenic effect compared with vacuum penetration. In juxtaposition, the transformation systems using both hairy root and leaf infiltration establish an efficient and convenient way to manipulate and analyze gene functions in quinoa, and a potential strategy for transgenic quinoa.

Soybeans are nutritionally important as human food and animal feed. Apart from the macronutrients such as proteins and oils, soybeans are also high in health-beneficial secondary metabolites and are uniquely enriched in isoflavones among food crops. Isoflavone biosynthesis has been relatively well characterized, but the mechanism of their transportation in soybean cells is largely unknown. Using the yeast model, we showed that GmMATE1 and GmMATE2 promoted the accumulation of isoflavones, mainly in the aglycone forms. Using the tobacco BrightYellow-2 (BY-2) cell model, GmMATE1 and GmMATE2 were found to be localized in the vacuolar membrane. Such subcellular localization supports the notion that GmMATE1 and GmMATE2 function by compartmentalizing isoflavones in the vacuole. Expression analyses showed that GmMATE1 was mainly expressed in the developing soybean pod. Soybean mutants defective in GmMATE1 had significantly reduced total seed isoflavone contents, whereas the overexpression of GmMATE1 in transgenic soybean promoted the accumulation of seed isoflavones. Our results showed that GmMATE1, and possibly also GmMATE2, are bona fide isoflavone transporters that promote the accumulation of isoflavones in soybean seeds.

Quinoa (Chenopodium quinoa Willd.) provides a gluten-free food with abundant nutrition and is potential to become a major crop in future. Quinoa has a lot of unique features including the high tolerance to multiple stresses, of which the underlying mechanisms may help improve other crops. Genetic manipulation will provide powerful tools to investigate the function of key genes in regulation of quinoa development and stress responses, which will further improve quinoa planting in the fields. However, the efficient transformation system for quinoa has not been well developed yet. Here, we established two rapid and efficient transformation systems for quinoa by using hairy root and leaf agroinfiltration, which provide useful tools for quick analyses of genes function in quinoa. Hairy roots were obtained from three types of explants, including cotyledon-nod with hypocotyl, cotyledon itself, and hypocotyl pieces. Interestingly, explants of cotyledon-nod with hypocotyl showed the highest transformation efficiency at 67.9%, and cotyledon displayed medium efficiency at 42.2%, while hypocotyl with the lowest at 31.6%. We also obtained transgenic quinoa roots successfully in-vivo, which showed low efficiency, but this provides a potential method to test gene function in live plants. By using young leaves for agroinfiltration, direct injection showed a better transgenic effect compared with vacuum penetration. Overall, the transformation systems using both hairy root and leaf agroinfiltration provide efficient and convenient ways to manipulate and analyse gene functions in quinoa.

The global population is on the path of an increasing trajectory with a simultaneous decline in arable land resources through salinization and desertification that have resulted mainly from climate change and other anthropogenic activities. Rising temperatures will cause changes in the entire ecosystem, resulting in significant alterations in global climate paradigms and a threat to food security. This review focuses on how the highly resilient Chenopodium quinoa Willd. can sustainably mitigate some of the detrimental impacts, such as starvation, and support or provide ecosystem services. In comparison, compared with the traditional staple food crops, quinoa has remarkable tolerance to abiotic stresses and is highly nutritious, with a unique balance and higher amounts of nutrients, and can therefore be an important crop for food security and nutritional adequacy. This crop has the potential to ameliorate global challenges with respect to increase in global population, effects of climate change, desalinization, phytoremediation, satisfying nutrient deficiency, and alleviating poverty.