Rhamnogalacturonan-I forms mucilage: behind its simplicity, a cutting-edge organizationSaez-Aguayo, Susana; Largo-Gosens, Asier
doi: 10.1093/jxb/erac094pmid: 36305092
Zhang Y, Yin Q, Qin W, Gao H, Du J, Chen J, Li H, Zhou G, Wu H, Wu A-M. 2022. The Class II KNOX family members KNAT3 and KNAT7 redundantly participate in Arabidopsis seed coat mucilage biosynthesis. Journal of Experimental Botany 73, 3477–3495.
Phyllotaxis without symmetry: what can we learn from flower heads?Prusinkiewicz, Przemyslaw; Zhang, Teng; Owens, Andrew; Cieslak, Mikolaj; Elomaa, Paula
doi: 10.1093/jxb/erac101pmid: 35275600
Phyllotaxis is commonly considered in the context of circular meristems or receptacles, yet non-circular (fasciated) structures also give rise to new primordia and organs. Here we investigate phyllotactic patterns in fasciated flower heads in the Asteraceae plant family. We begin by surveying the phenomenon of fasciation. We then show that phyllotactic patterns in fasciated heads can be generated by removing the inessential assumption of circularity from the previously published model of gerbera heads. To characterize these patterns, we revisit the conceptual framework in which phyllotactic patterns are commonly described. We note that some notions, in particular parastichies and parastichy numbers, maintain their significance in non-circular phyllotaxis, whereas others, in particular the divergence angle, need to be extended or lose their role. These observations highlight a number of open problems related to phyllotaxis in general, which may be elucidated by studies of fasciated heads.
Plant responses to climate change: metabolic changes under combined abiotic stressesZandalinas, Sara I; Balfagón, Damián; Gómez-Cadenas, Aurelio; Mittler, Ron
doi: 10.1093/jxb/erac073pmid: 35192700
Climate change is predicted to increase the frequency and intensity of abiotic stress combinations that negatively impact plants and pose a serious threat to crop yield and food supply. Plants respond to episodes of stress combination by activating specific physiological and molecular responses, as well as by adjusting different metabolic pathways, to mitigate the negative effects of the stress combination on plant growth, development, and reproduction. Plants synthesize a wide range of metabolites that regulate many aspects of plant growth and development, as well as plant responses to stress. Although metabolic responses to individual abiotic stresses have been studied extensively in different plant species, recent efforts have been directed at understanding metabolic responses that occur when different abiotic factors are combined. In this review we examine recent studies of metabolomic changes under stress combination in different plants and suggest new avenues for the development of stress combination-resilient crops based on metabolites as breeding targets.
Molecular basis of priming-induced acquired tolerance to multiple abiotic stresses in plantsNair, Akshay U; Bhukya, Durga Prasad Naik; Sunkar, Ramanjulu; Chavali, Sreenivas; Allu, Annapurna Devi
doi: 10.1093/jxb/erac089pmid: 35274680
The growth, survival, and productivity of plants are constantly challenged by diverse abiotic stresses. When plants are exposed to stress for the first time, they can capture molecular information and store it as a form of memory, which enables them to competently and rapidly respond to subsequent stress(es). This process is referred to as a priming-induced or acquired stress response. In this review, we discuss how (i) the storage and retrieval of the information from stress memory modulates plant physiological, cellular, and molecular processes in response to subsequent stress(es), (ii) the intensity, recurrence, and duration of priming stimuli influences the outcomes of the stress response, and (iii) the varying responses at different plant developmental stages. We highlight current understanding of the distinct and common molecular processes manifested at the epigenetic, (post-)transcriptional, and post-translational levels mediated by stress-associated molecules and metabolites, including phytohormones. We conclude by emphasizing how unravelling the molecular circuitry underlying diverse priming-stimuli-induced stress responses could propel the use of priming as a management practice for crop plants. This practice, in combination with precision agriculture, could aid in increasing yield quantity and quality to meet the rapidly rising demand for food.