Low temperature is a key factor that limits growth and productivity of many important agronomical crops worldwide. Rice (Oryza sativa L.) is negatively affected already at temperatures below +10°C and is therefore denoted as chilling sensitive. However, chilling tolerant rice cultivars exist and can be commercially cultivated at altitudes up to 3,050 meters with temperatures reaching as low as ...

A decline in rice (Oryza sativa L.) production caused by heat stress is one of the biggest concerns resulting from future climate change. Rice spikelets are most susceptible to heat stress at flowering. The early-morning flowering (EMF) trait mitigates heat-induced spikelet sterility at the flowering stage by escaping heat stress during the daytime. We attempted to develop near-isogenic lines (...

We developed a new method of using seedling trays to evaluate root angle distribution in rice (Oryza sativa. L), and found a wide genetic variation among cultivars. The seedling tray method can be used to evaluate in detail the growth angles of rice crown roots at the seedling stage by allocating nine scores (10° to 90°). Unlike basket methods, it can handle large plant populations over a short...

Rice blast, caused by the fungus, Magnaporthe grisea, is a common disease of rice in Arkansas. The disease has reached epidemic levels previously in Arkansas on susceptible cultivars. Also, it has been established that artificially infected seeds placed on the soil surface could initiate disease in small plots. The research reported here was conducted in small plots to determine if naturally in...

Global climate change combined with asymmetric warming can have detrimental effects on the yield of crop plants such as rice (Oryza sativa L.). Little is known about metabolic responses of rice to high night temperature (HNT) conditions. Twelve cultivars with different HNT sensitivity were used to investigate metabolic changes in the vegetative stage under HNT compared to control conditions. Ce...

Coleoptiles of rice seeds that germinate under anoxia usually elongate to a length far exceeding the elongation that takes place under aerobic conditions. It has been suggested that expansins play a role in this process, but studies examining correlations between transcript levels of expansin genes and anoxic growth of rice coleoptiles are limited. In this study, we used real-time quantitative ...

Plant colonization by bradyrhizobia is found not only in leguminous plants but also in nonleguminous species such as rice. To understand the evolution of the endophytic symbiosis of bradyrhizobia, the effect of the ecosystems of rice plantations on their associations was investigated. Samples were collected from various rice (Oryza sativa) tissues and crop rotational systems. The rice endophyti...

MicroRNAs (miRNAs) are known to play critical roles in plant development and stress-response regulation, and they frequently display multi-targeting characteristics. The control of defined rice phenotypes occurs through multiple genes; however, evidence demonstrating the relationship between agronomic traits and miRNA expression profiles is lacking. In this study, we investigated eight yield-re...

the present investigation was carried out to examine virulence diversity among the 291isolates (seven populations) of rhizoctonia solani ag-1 ia causing sheath blight of rice by sclerotia production and pathogencity studies on four rice cultivars representing different observed disease reactions, using detached leaf inoculation method in conjunction with mycelia growth measuring. based on patho...

Insertion-deletion (indel) polymorphisms, such as simple sequence repeats, have been widely used as DNA markers to identify QTLs and genes and to facilitate rice breeding. Recently, next-generation sequencing has produced deep sequences that allow genome-wide detection of indels. These polymorphisms can potentially be used to develop high-accuracy polymerase chain reaction (PCR)-based markers. ...