The AVR-Pita1 gene, from the Chinese isolate O-137 of Magnaporthe oryzae, is an effector that determines the efficacy of the Pi-ta rice blast resistance gene. In the present study, the avirulence function of AVR-Pita1 was induced by transformation of field isolates (TM2, ZN19, B2 and B8) that originally were collected from the U.S. and are virulent on Pi-ta-carrying rice cultivars. The presence of AVR-Pita1 from O-137 in independent transformants was detected by PCR using AVR-Pita1 specific primers and verified by DNA sequencing and Southern blot analysis using the AVR-Pita1 coding region as a probe. The results of pathogenicity assays showed that the AVR-Pita1-transformed isolates were not able to infect rice cultivars Katy and Drew carrying Pi-ta. Control isolates that were transformed with inserts lacking the AVR-Pita1 gene remained virulent. Our findings demonstrate that AVR-Pita1 can be used to induce novel gene-specific blast resistance in nature.

A total of 43 unique clones (Z4A-1 to Z4A-43 with GenBank accession numbers of HM120221, HM120222, JX828270, JN831402 to JN831406, and KC715889 to KC715923, respectively) were amplified and cloned from common wheat cultivar Zhengmai 004 using a PCR-based strategy. They included 22 full-ORF α-gliadin genes and 21 pseudogenes containing at least one in-frame stop codon. Comparative analysis of the deduced amino acid sequences showed that all the isolated genes displayed the typical structural features of α-gliadin genes and that the putative proteins of Z4A-7, Z4A-14, Z4A-17 and Z4A-20 had an extra cysteine residue in the unique domain II, while Z4A-15 lacked the second conserved cysteine residue in the unique domain I. The two fusion proteins of Z4A-15 and Z4A-20 were successfully detected by SDS-PAGE and Western blotting, although the protein level was relatively low. Based on the occurrence of the four major epitopes, as well as the lengths of the two glutamine repeats, 8, 6, and 8 genes were assigned to the Gli-2 loci on the respective chromosomes 6A, 6B, and 6D and a total of respectively 16, 0 and 23 immunogenic peptides were identified. In addition, 4 of the 5 genes with odd numbers of cysteine residues were assigned to chromosome 6D, suggesting that common wheat cultivar Zhengmai 004 has the potential to induce celiac disease (CD) and that the D genome exerts the most influence on gluten quality, but is the most deleterious for CD patients. By phylogenetic analysis, 11 exceptional α-gliadins with few or no immunogenic peptides from Triticum monococcum and Aegilops tauschii were detected, a finding that further supports the prospect of CD prevention. Finally, secondary structure prediction showed that most (98.48%) of the α-gliadins invariably contained five conserved α-helices (H1 to H5) in the two glutamine repeats and unique domains and 67.68% of the α-gliadins also contained a β-strand (S) in the C-terminal unique domains. An absent α-helix H₂, 1-2 extra α-helices, or an additional β-strand (S_E) also probably occurred in some cases. Of the 22 cloned genes in this work, 10 putative proteins contained 1-2 extra α-helices in addition to the five conserved α-helices or the additional β-strand. The observation that most of the α-helices and β-strands were present in the two unique domains and that an extra α-helix also probably occurred in the two glutamine repeats in some desirable genes strongly suggested that these two unique domains are the most important regions for the function of α-gliadins, although the glutamine repeats would also contribute in some cases.

Plant photosynthetic rate is affected by stomatal status and internal CO₂ carboxylation. Understanding which process determines photosynthetic rate is essential for developing strategies for breeding crops with high photosynthetic efficiency. In this study, we identified different physiological patterns of photosynthetic rate in two different rice populations. Photosynthetic gas exchange parameters were measured during the flowering stage in two rice populations. Clustering and correlation analyses were performed on the resulting data. Five or six groups were defined by K-means clustering according to differences in net photosynthetic rates (P_n). According to differences in stomatal conductance (g_s) and carboxylation efficiency (CE), each group was clustered into three subgroups characterized by physiological patterns stomatal pattern, carboxylation pattern, and intermediate pattern. P_n was significantly correlated with g_s (r = 0.810) and CE (r = 0.531). P_n was also significantly correlated with g_s and CE in the three physiological patterns. The correlation coefficients were highest in the stomatal pattern (0.905 and 0.957) and lowest in the carboxylation pattern (0.825 and 0.859). Higher correlation coefficients between P_n and g_s or CE in the three physiological patterns indicate that clustering is very important for understanding factors limiting rice photosynthesis.

To analyze the nutritional composition of faba bean (Vicia faba L.) seed, estimation models were developed for protein, starch, oil, and total polyphenol using near infrared spectroscopy (NIRS). Two hundred and forty-four samples from twelve producing regions were measured in both milled powder and intact seed forms. Partial least squares (PLS) regression was applied for model development. The model based on ground seed powder was generally superior to that based on the intact seed. The optimal seed powder-based models for protein, starch, and total polyphenol had coefficients of correlation (r²) of 0.97, 0.93 and 0.89, respectively. The relationship between nutrient contents and twelve producing areas was determined by two-step cluster analysis. Three distinct groupings were obtained with region-constituent features, i.e., Group 1 of high oil, Group 2 of high protein, and Group 3 of high starch as well as total polyphenol. The clustering accuracy was 79.5%. Moreover, the nutrition contents were affected by seeding date, longitude, latitude, and altitude of plant location. Cluster analysis revealed that the differences in the seed were strongly influenced by geographical factors.

The concept of core collection (CC) provides a new way of management and utilization of plant germplasm resources. In this study, an integrated applied core collection (IACC) of soybean was developed based on evaluation data for desirable agronomic and nutritional traits of available soybean germplasm resources including accessions with cold tolerance, drought tolerance, salt tolerance, soybean cyst nematode resistance, soybean mosaic virus resistance, high protein content, and high fat content. The newly formed collection encompasses accessions with high genetic diversity and desirable agronomic traits. The genetic diversity of the newly formed IACC was compared with that of the established mini core collection (MCC) of soybean with the aid of simple sequence repeat (SSR) markers and phenotypic traits. The results showed that at the molecular level, soybean IACC harbored a similar level of genetic diversity as the established MCC, and that at the phenotypic level the IACC encompasses more accessions with desirable traits than does the established MCC. The development of soybean IACC lays a foundation for breeding projects to meet different objectives in different eco-regions.

This study provided visual evidence of a nitrogen effect on starch granules (SGs) in wheat endosperm. Winter wheat (Titicum aestivum L.) cultivar Xumai 30 was cultured under no nitrogen (control) and 240 kg ha^{− 1} of nitrogen applied at the booting stage. The number, morphology, and size of A- and B-type SGs in subaleurone of dorsal endosperm (SDE), center of dorsal endosperm (CDE), modified aleurone (MA), subaleurone of ventral endosperm (SVE), and center of ventral endosperm (CVE) were observed under light and electron microscopes. (1) The distribution of SGs in SDE was similar to that in SVE, the distributions of SGs in CDE and CVE were similar, but the distribution of SGs in MA was different from those in the other four endosperm regions. The number of SGs in the five endosperm regions was in the order SDE > CDE > SVE > CVE > MA. (2) Nitrogen increased the number of A- and B-type SGs in SDE and SVE. Nitrogen also increased the number of B-type SGs but decreased the number of A-type SGs in CDE and CVE. Nitrogen decreased the numbers of A-type and B-type SGs in MA. The results suggest that increased N fertilizer application mainly increased the numbers of small SGs and decreased the numbers of large SGs, but that the results varied in different regions of the wheat endosperm.

The small brown planthopper (SBPH), Laodelphax striatellus Fallén (Homoptera: Delphacidae), is a serious pest of rice (Oryza sativa L.) in China. To understand the mechanisms of rice resistance to SBPH, defense response genes and related defense enzymes were examined in resistant and susceptible rice varieties in response to SBPH infestation. The salicylic acid (SA) synthesis-related genes phenylalanine ammonia-lyase (PAL), NPR1, EDS1 and PAD4 were induced rapidly and to a much higher level in the resistant variety Kasalath than in the susceptible cultivar Wuyujing 3 in response to SBPH infestation. The expression level of PAL in the Kasalath rice at 12 h post-infestation (hpi) increased 7.52-fold compared with the un-infested control, and the expression level in Kasalath was 49.63, 87.18, 57.36 and 75.06 times greater than that in Wuyujing 3 at 24, 36, 48 and 72 hpi, respectively. However, the transcriptional levels of the jasmonic acid (JA) synthesis-related genes LOX and AOS2 in resistant Kasalath were significantly lower than in susceptible Wuyujing 3 at 24, 36, 48 and 72 hpi. The activities of the defense enzymes PAL, peroxidase (POD), and polyphenol oxidase (PPO) increased remarkably in Kasalath in response to SBPH infestation, and were closely correlated with the PAL gene transcript level. Our results indicated that the SA signaling pathway was activated in the resistant Kasalath rice variety in response to SBPH infestation and that the gene PAL played a considerable role in the resistance to SBPH.

The impacts of nighttime post-anthesis warming on rice productivity and grain quality in East China were evaluated for two cultivars, II You 128, an indica rice, and Wuyunjing 7, a japonica rice. Warming by 3.0 °C stimulated the nighttime respiration rate and decreased the photosynthesis rate, resulting in significant decreases of 21.2% and 24.9% in aboveground biomass accumulation for II You 128 and Wuyunjing 7, respectively. Warming significantly reduced the rates of seed setting and grain filling, especially of inferior kernels (those lower in panicles), while the filling rate of superior kernels remained almost unchanged. As a result, 1000-grain weight and grain yield were respectively 3.7% and 30.0% lower for II You 128 and 12.8% and 34.3% for Wuyunjing 7 in warmed plots than in the unwarmed control. Nighttime warming also significantly reduced the grain milling and appearance quality of both varieties. More negative effects of warming on inferior than on superior kernels were found. The above results have important implications for rice variety cultivation in East China.

Fusarium head blight (FHB), caused by Fusarium graminearum, is one of the most destructive wheat (Triticum aestivum L.) diseases worldwide. Identification of quantitative trait loci (QTL) conferring FHB resistance followed by marker assisted selection (MAS) is an efficient approach to breed FHB-resistant varieties. In this study, 38 additive QTL and 18 pairs of epistatic QTL for FHB resistance were detected in four environments using a population of recombinant inbred lines (RILs) derived from varieties Neixiang 188 and Yanzhan 1. Six QTL clusters were located on chromosomes 2D, 4B, 4D, 5A, 5D and 7B, suggesting possible polytrophic functions. Six elite lines with good FHB resistance and agronomic traits were selected from the same population using the associated markers. Our results suggest that MAS of multiple QTL will be effective and efficient in wheat breeding.

Tillering is an important agronomic trait for rice grain production. To evaluate yield and tillering response, Liangyoupeijiu (super hybrid rice) was grown in Hunan, China during 2011-2012 under different methods of tillage (conventional and no-tillage system) and crop establishment methods (transplanting at a spacing of 20 cm × 20 cm with one seedling per hill and direct seeding at a seeding rate of 22.5 kg ha^{− 1}). Our results revealed that, at maximum tillering (Max.) and at maturity (MA) stages, direct seeding (DS) resulted in 22% more tillers than transplanting (TP) irrespective of tillage system. Tiller mortality reached a peak between panicle initiation (PI) and booting (BT) stages, and was 16% higher under conventional tillage (CT) than under no-tillage (NT). Transplanting required 29% more time for the completion of tillering and less for DS. Tillering rate was 43% higher in DS than TP under either CT or NT. There was a positive correlation between panicle number per m² and maximum tiller number per m²,and maximum tiller number per m² and maximum tiller number per m², but not panicle-bearing tiller rate. The panicle bearing tiller rate was higher under DS than TP and higher under NT than CT. Tiller dry weight gradually increased up to heading (HD) stage, and was 14% higher under TP than DS. Leaf area (cm² tiller^{− 1}) gradually increased from Max. to HD stage and then decreased by 34% in conventional tillage transplanting (CTTP) and 45% in no-tillage transplanting (NTTP) from 12DAH-24DAH (days after heading), but was similar (35%) under DS under either CT or NT. Grain yield was higher under CTTP owing to the larger sink size (heavier panicle, more spikelets in per cm length of panicle) than under DS.