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The family members of PEX11 are key factors involved in regulation of peroxisome proliferation. Sixty-six PEX11p candidates of PEX11 gene family from 26 representative fungal species were obtained and analyzed by bioinformatic strategies. In most filamentous fungi, 2 or 3 potential PEX11ps were found, in contrast with 1 or 2 in yeast species. Compared with other fungal species, the Ascomycetes tend to have more PEX11ps, and even 5 in several individuals. The data of phylogenetic analysis and protein structure indicated that all of the PEX11ps were divided into 3 groups: I, II, and III. The members of group I and group III existed in most species, while those in group II were found only in Pezizomycotina. By MEME analysis, 5-6 conserved motifs were found in each PEX11ps. Among them,motif 8 in C-terminal had the most conservation, indicating that this motif probably plays a key role in maintaining the proper function of PEX11p.

Site-specific variable pesticide application is one of the major precision crop production management operations. Rice blast is a severe threat for rice production. Traditional chemistry methods can do the accurate crop disease identification, however they are time-consuming, require being executed by professionals and are of high cost. Crop disease identification and classification by human sight need special crop protection knowledge, and is low efficient. To obtain fast, reliable, accurate rice blast disease information is essential for achieving effective site-specific pesticide applications and crop management. The present paper describes a multi-spectral leaf blast identification and classification image sensor, which uses three channels of crop leaf and canopy images. The objective of this work was to develop and evaluate an algorithm under simplified lighting conditions for identifying damaged rice plants by the leaf blast using digital color images. Based on the results obtained from this study, the seed blast identification accuracy can be achieved at 95%, and the leaf blast identification accuracy can be achieved at 90% during the rice growing season. Thus it can be concluded that multi-spectral camera can provide sufficient information to perform reasonable rice leaf blast estimation.

Targeted gene replacement (TGR) is an important technique for gene function analysis. With the development of genome sequencing and transformation, TGR has been applied widely to filamentous fungi, and many new systems and approaches have been established. In this paper, strategies involved in TGR in filamentous fungi were reviewed, including transformation systems, targeting vector construction, mutant selection and so on. Compared with TGR, RNAi and other techniques of gene function analysis were introduced and reviewed as well.

In a recombinant inbred line (RIL) population of indica rice, two subpopulations composed of susceptible lines were selected for mapping of partial resistance to leaf blast with two isolates of the pathogen. A third subpopulation composed of susceptible lines with similar heading time was used for mapping of partial resistance to neck blast with a third isolate. The traits measured for partial resistance included diseased leaf area (DLA), lesion size (LS) and lesion number (LN) for leaf blast and lesion length (LL) and conidium amount (CA) for neck blast. A linkage map consisting of 168 DNA markers was constructed by using the whole RIL population. Quantitative trait loci (QTLs) conditioning these traits were determined at one-locus and two-locus levels. Eleven main-effect QTLs and 28 digenic interactions were detected by QTLMapper 1.01 b. Only three QTLs showing main effects were also involved in digenic interactions for the same trait. General contributions of epistatic QTLs of each trait ranged from 16.0% to 51.7%, while those of main-effect QTLs of each trait ranged from 4.7% to 38.8%. The general contributions of main-effect QTLs of most traits were smaller than those of epistatic QTLs, confirming the importance of epistasis as the genetic basis for complex traits. The general contributions of the main and epistatic effects of all QTLs detected for the two traits LL and CA of the partial resistance to neck blast reached 70.6% and 82.6% respectively, which obviously represented a major part of the genetic basis controlling partial resistance to neck blast. The results indicated the necessity for partial resistance mapping to use susceptible subpopulations where the interference of major resistance genes is avoided.

A pair of near isogenic lines G205 and G71 were selected from recombinant inbred lines (RIL) of Zhong156 x Gumei2. On the resistance locus Pi-25(t), G205 had the resistant allele that was from Gumei 2 while G71 had the susceptible allele that was from Zhong156. For the genetic background, different alleles were detected on only 24 loci out of the 672 RFLP or SSLP loci surveyed. The expression profiles of G205 and G71 in response to Magnaporthe grisea were investigated using cDNA microarray containing 2200 Expression Sequence Tags (ESTs). The leaves were inoculated with the pathogen for 12 hours at 4-leaf stage and 998 genes were identified in total. Three genes were up-regulated significantly by the fungus in G205 only. The functions of two genes were known but that of the third gene were unknown. The two genes encoded casein kinase II alpha subunit and retrotransponson TOS17 insertion element respectively. Other thirty-five genes had similar expression patterns between NILs. Among them, 17 genes were up-regulated while 18 genes were down-regulated by the inoculation. The functions of 33 out of the 35 genes were known. BLAST analysis showed that all thirty-five. BLAST analysis showed that all thirty-five genes with known functions were relative to defense reactions, signal transduction, stress response, photosynthesis and sugar metabolism. Northern blot confirmed that four of five differentially displayed genes randomly selected had the same expression patterns as those detected in cDNA microarray. Two of them were up-regulated genes encoding casein kinase II alpha subunit and glycine-rich protein (Grp), and the other two down-regulated genes encoding nitrilase-associated protein and 18S small subnit ribosomal RNA gene respectively. Northern blot also revealed that the expression of Grp was consistently up-regulated from 0 to 36 h after the inoculation of the fungus. These results showed that cDNA microarray was a useful tool to study the molecular mechanisms of disease resistance in plants.