Panicle Apical Abortion 7 Regulates Panicle Development in Rice (Oryza sativa L.)

Abstract

The number of grains per panicle significantly contributes to rice yield, but the regulatory mechanism remains largely unknown. Here, we reported a loss-of-function mutant, panicle apical abortion 7 (paa7), which exhibited panicle abortion and degeneration of spikelets on the apical panicles during the late stage of young panicle development in rice. High accumulations of H2O2 in paa7 caused programmed cell death (PCD) accompanied by nuclear DNA fragmentation in the apical spikelets. Map-based cloning revealed that the 3 bp “AGC” insertion and 4 bp “TCTC” deletion mutation of paa7 were located in the 3′-UTR regions of LOC_Os07g47330, which was confirmed through complementary assays and overexpressed lines. Interestingly, LOC_Os07g47330 is known as FRIZZY PANICLE (FZP). Thus, PAA7 could be a novel allele of FZP. Moreover, the severe damage for panicle phenotype in paa7/lax2 double mutant indicated that PAA7 could crosstalk with Lax Panicle 2 (LAX2). These findings suggest that PAA7 regulates the development of apical spikelets and interacts with LAX2 to regulate panicle development in rice.

Analysis of Accidents in the Oil and Gas Industry in Kuwait

“…From the chart, it can be seen that there is no pattern or a particular correlation in the accidents that occurred in the multiple activities. However, it definitely shows the presence of human factors as there is no consistent reduction but more of an random [24] occurrence of deaths in the past decade. Therefore, Figure 4 confirms the requirement to manage human factors to minimize the risks that each task/ activity possesses when humans interact with the activity and system of activity.…”

“…Insufficient situational awareness, poor work order and wrong order found to be common unsafe acts. The combined HFACS and SEM models were used to study how unsafe behaviours are affected by safety culture at nuclear power plants in China [24]. Inadequate supervision, organizational processes, skill-based errors, and physical environment were found to be most influential factors on latent variables.…”