Molecular Mechanisms behind the Regulation of Rice Tiller Angle: An Update
Rao Saad Rehman *
College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China.
Asad Nadeem Pasha
Department of Plant Pathology, Bahauddin Zakariya University, Multan, Pakistan.
Syed Ali Zafar
Oilseeds Research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan.
Mujahid Ali
Department of Plant Breeding and Genetics, Nanjing Agricultural University, Nanjing, China.
Hassan Bashir
Department of Plant Breeding and Genetics, Sub Campus Burewala-Vehari, University of Agriculture Faisalabad, Pakistan.
Muhammad Usama Saeed
Institute of Horticultural Sciences, University of Agriculture Faisalabad, Pakistan.
Naveed Ali Ashraf
Department of Seed Science and Technology, University of Agriculture Faisalabad, Pakistan.
Abdullah Javed
Department of Seed Science and Technology, University of Agriculture Faisalabad, Pakistan.
*Author to whom correspondence should be addressed.
Abstract
Crop plant architecture is an important agronomic trait that contributes greatly to crop yield. Tiller angle is one of the most critical components that determine crop plant architecture, which in turn substantially affects grain yield mainly owing to its large influence on plant density. Gravity is a fundamental physical force that acts on all organisms on earth. Plant organs sense gravity to control their growth orientation, including tiller angle in rice (Oryza sativa). This review summarizes recent research advances made using rice tiller angle as a research model, providing insights into domestication of rice tiller angle, genetic regulation of rice tiller angle, and shoot gravitropism. Finally, we propose that current discoveries in rice can shed light on shoot gravitropism and improvement of plant tiller angle in other species, thereby contributing to agricultural production in the future.
Keywords: Tiller angle, shoot gravitropism, gravity-sensing tissues, amyloplast sedimentation, environmental plasticity, transcription factors