A mutant was isolated from the M2 of 60Co-g ray mutagenized male-fertility restorer line Zao-R974 in rice. The mutant showed pleiotropic phenotypes including dwarfism, delayed heading time, short and partially enclosed panicles, short uppermost internode, decreased grain and secondary branch numbers per panicle, and partially degenerated spikelets. The mutant was named as esp1 (enclosed shorter panicle 1). Genetic analysis indicated that the mutant phenotype was controlled by a recessive locus. Spraying exogenous GA3 did not rescue the panicle enclosure. Using an F2 and a BC1 population of the cross between esp1 and a japonica cultivar Nipponbare, we mapped the ESP1 locus to a region of ~260 kb on chromosome 11. This result provides a basis for further map-based cloning of the ESP1 locus.

Magnaporthe oryzae, a filamentous ascomycete fungus, is well known as the causal agent of rice blast. With thetechnology of suppression subtractive hybridization (SSH), it was previously found that MGG_06001 (or named MoNEM1),a gene of M. oryzae homologous to the NEM1 (nuclear envelope morphology protein 1) gene of baker’s yeast(Saccharomyces cerevisiae), is differentially expressed between the mature appressium and the conidium and mycelium.This study aimed to characterize the function of MoNEM1 gene by knocking it out using the method of target genereplacement. The ΔMonem1 mutants exhibited reduced mycelial growth and conidiation. However, disruption of MoNEM1gene does not affect the pathogenicity of M. oryzae on barley and rice.

A row-type mutant of barley named poly-row-and-branched spike (prbs) was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRBS locus had a recessive epistatic effect on an independent locus (denoted as Vrsx) conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRBS as well as Vrsx using simple sequence repeats (SSR) markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type:sixrowed type:prbs=9:3:4 in the population, we adopted a special strategy to map the two loci. PRBS was mapped between SSR markers HvLTPPB and Bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers Bmag0125 and Bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRBS is a new locus related to the row type of spikes in barley.