Light exposure is an important environmental factor which breaks seed dormancy in many plant species. Phytochromes have been identified as playing a crucial role in perception of the light signal that releases seed germination in Arabidopsis. Phototropins (Phot1, Phot2) are blue/UV-photoreceptors in plants which mediate phototropic responses, chloroplast relocation, hypocotyl growth inhibition and stomata opening. We studied germination under different light conditions in Arabidopsis Phot1-null and Phot2-null mutants and in a double phot1phot2 mutant. Germination of single phot1 and phot2 mutants in darkness was much lower than in wildtype (WT) seeds, whereas double phot1phot2 mutant lacking both functional phototropins germinated at frequency comparable to WT seeds, irrespective of light and temperature conditions. Light treatment of imbibed seeds was essential for effective germination of phot1, irrespective of low-temperature conditioning. In contrast, cold stratification promoted dark germination of phot2 seeds after imbibition in dim light. Low germination frequency of phot1 seeds under low light intensity suggests that the presence of functional Phot1 might be crucial for effective germination at these conditions. The lower germination frequency of phot2 seeds under continuous light suggests that Phot2 might be responsible for stimulating germination of seeds exposed to direct daylight. Thus, the phototropin system may cooperate with phytochromes regulating the germination competence of seeds under different environmental conditions

The current research aimed to use non traditional methods to control some stored grain insects. The effects of 180 millitesla (mT) magnetic field (MF) for six different exposure periods (3 min, 30 min, 1 h, 12 h, 24 h and 48 h) on mortality (%) of two stored grain insects, Tribolium casteneum adults and Trogoderma granarium larvae, reduction in F1-progeny (%), seeds germination (%) and seed components (%) after 8 months storage period were studied under laboratory conditions. According to results, the mortality (%) of tested insects increased with increasing of MF time exposure. Trogoderma granarium was more resistant than T. casteneum in which mortality reached 56 and 75%, respectively 14 days after from exposure period. Without any negative effect on seeds germination (%) the MF was very effective in protecting stored wheat from insect infestation up to 8 months compared to non-magnetic seeds which became infested after 3 months of storage. Furthermore, the germination (%) was accelerated by 6 h compared to non-magnetic seeds. The MF level caused a slight increase in the percent of total carbohydrate, crude protein and ash while slightly decrease the percent of moisture, total fats and crude fiber.

Pantoea species (Pantoea spp.) is a diverse group of Gram-negative bacteria in the Enterobacteriaceae family that leads to devastating diseases in rice plants, thus affecting significant economic losses of rice production worldwide. Most critical rice diseases such as grain discoloration, bacterial leaf blight, stem necrosis and inhibition of seed germination have been reported to be caused by this pathogen. To date, 20 Pantoea spp. have been identified and recognized as having similar phenotypic and diverse characteristics. Detection via phenotypic and molecular-based approaches, for example the polymerase chain reaction (PCR) and multiplex PCR give us a better understanding of the diversity of Pantoea genus and helps to improve effective disease control strategies against this emergent bacterial pathogen of rice. In this review, we focused on the significance of rice diseases caused by Pantoea spp. and insights on the taxonomy and characteristics of this destructive pathogen via phenotypic and molecular identification.