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Soil erosion features and ideal tillage practices are not very clear at the crop seedling stage in Chinese Mollisols. Simulated rainfall experiments were conducted at the rainfall intensities of 50 and 100 mm h-1 to investigate the differences in soil erosion of a 5° hillslope during the maize seedling stage between conservation and conventional tillage measures, including cornstalk mulching (Cm), horizontal ridging (Hr), horizontal ridging + mulching (Hr+Cm), vertical ridging + mulching (Vr+Cm), flat-tillage (CK), and vertical ridging (Vr). The results demonstrated that crops could remit soil erosion at the seedling stage by reducing the kinetic energy and changing the distribution of raindrops. The conservation tillage measures significantly alleviated total runoff (11.7 %–100 %) and sediment yield (71.1 %–100 %), postponed runoff-yielding time (85 s–26.1 min), decreased runoff velocity (71.5 %–96.7 %), and reduced runoff and soil loss rate, compared to the conventional tillage measures. Practices with mulching showed better performance than Hr. Mulching reduced sediment concentration (~70.6 %–100 %) by decreasing runoff velocity and soil particle filtration in a manner similar to buffer strips. The contour ridge ruptured earlier at 100 mm h-1 than at 50 mm h-1 and changed the characteristics of the soil erosion by providing a larger sediment source to the surface flow. Runoff strength, rather than soil erodibility, was the key factor affecting soil erosion. Decreasing runoff velocity was more important than controlling runoff amount. The Hr + Cm treatment exhibited the lowest soil erosion and is, thus, is recommended for adoption at the corn seedling stage in sloping farmlands. [ABSTRACT FROM AUTHOR]

Arabidopsis cryptochrome 2 (CRY2) and FLAVIN-BINDING, KELCH REPEAT, and F-BOX 1 (FKF1) are blue light receptors mediating light regulation of growth and development, such as photoperiodic flowering. CRY2 interacts with a basic helix–loop–helix transcription factor CIB1 in response to blue light to activate the transcription of the flowering integrator gene FLOWERING LOCUS T (FT). CIB1, CIB2, CIB4, and CIB5 function redundantly to promote flowering in a CRY2-dependent way and form various heterodimers to bind to the noncanonical E-box sequence in the FT promoter. However, the function of CIB3 has not been described. We discovered that CIB3 promotes photoperiodic flowering independently of CRY2. Moreover, CIB3 does not interact with CRY2 but interacts with CIB1 and functions synergistically with CIB1 to promote the transcription of the GI gene. FKF1 is required for CIB3 to promote flowering and enhances the CIB1–CIB3 interaction in response to blue light. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) and Jasmonic acid (JA) are two key signaling molecules involved in many and diverse biological pathways in plants. Growing evidence suggested that NO signaling interacts with JA signaling. In this work, Our experiment showed that NO exists in guard cell of Vicia faba L., and NO is involved in signal transduction of JAinduced stomata closuring: ( i ) JA enhances NO synthesis in guard cell; ( ii ) both JA and NO induced stomatal closure, and had dose response to their effects; (iii) there are synergetic correlation between JA and lower NO concentration in regulation of stomatal movement; (iv) JA-induced stomatal closure was largely prevented by 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger. An inhibitor of NO synthase (NOS) in mammalian cells, NG-nitro-L-Arg-methyl eater (L-NAME) also inhibits plant NOS, repressing JA-induced NO generation and JA-induced stomatal closure. We presumed that NO mainly comes from NOS after JA treatment. [ABSTRACT FROM AUTHOR]

In order to obtain salt-tolerant variant plants of Dandelion (Taraxacum officinale Weber), the leaf discs were excised from 20 to 30-day old seedlings to produce callus, then the induced calli were transferred to selection mediums containing 1.5% NaCl. After regenerating and rooting, these salt-tolerant calli finally developed into 12 variant plantlets. Compared with the wild-type, these regenerated plants produced more trichomes on their leaves, and had larger leaves and shorter petioles. Additionally, the dumpy roots and an approximately 2-cm bract in middle parts of the floricanes were clearly observed in these salt-tolerant plants. By RAPD (Random Amplified Polymorphic DNA) and SDS-PAGE analysis, these salt-tolerant plants showed differences from the control at DNA and protein levels. With 1.5% NaCl treatment, the antioxidant enzyme activity, proline content, and flavonoid concentration were higher in these salt-tolerant plants, whereas maloaldehyde concentration was significantly lower. Salt-tolerant lines of T. officinale showed stronger anti-oxidative activity and higher flavonoid contents.