Chloroplast biogenesis and its molecularcomplexities are still under characterization. The chloroplast itself can beconsidered as a separate entity within the plant cell because it contains itsown genome. The genetic system of chloroplast and its coordination with thenucleocytosolic system, the routing and import of nucleus encoded proteinstogether with the organellar division, all contribute to the biogenesis ofchloroplast. They are controlled by the ubiquitin proteasome system which ispart of a network of regulatory mechanisms that intergrade development intobroader programs of cellular development (Jarvis and Lopez-Juez, 2013). Thethylakoids are considered as one of the most important structures withinchloroplast, and are the internal lipid membranes full of protein complexeswhich provide a platform for the light reactions occurred during photosynthesis(Pribil et al. 2014). In monocotyledon plants like rice (Oryza sativa) genetic studies have shown a different regulation ofchloroplast biogenesis at the adaxial and abaxial side between the midrib ofthe leaf and the rest of the leaf blade.
In a rice chromatin-remodelling factor4 (chr4) mutant, it was observed analbino phenotype only at the adaxial side of the leaves, due to a selectivedown-regulation of chloroplast development genes in cells of the adaxial side(Zhao et al. 2012). Cold stress is a major abiotic constraint to plant growthand development. In rice, two stages of development play a crucial role and areknown to be sensitive to low temperatures; the seedling stage and the bootingstage.
At the seedling stage, low temperatures reduce germination and delayleaf emergence. Common symptoms in this problem are leaf chlorosis andyellowing (Cruz et al. 2013), suggesting that low temperature arrestschloroplast development and functioning. During the booting stage, a lowtemperature cause pollen sterility and as a consequence is the decrease ingrain yield (Cruz et al.
2013). A low temperature causes swelling of thethylakoid lamellae, vesiculation of the thylakoid, and ultimately damage of theentire chloroplast. Low temperatures can affect and inhibit electron transportand the carbon assimilation apparatus such as the Calvin cycle, ATP synthase,and RuBisCo (Yamori et al. 2011; Hasanuzzaman et al 2013).