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The variation of phyllosphere bacterial and fungal communities along elevation gradients may provide a potential link with temperature, which corresponds to an elevation over short geographic distances. At the same time, the plant growth stage is also an important factor affecting phyllosphere microorganisms. Understanding microbiological diversity over changes in elevation and among plant growth stages is important for developing crop growth ecological theories. Thus, we investigated variations in the composition of the rice phyllosphere bacterial and fungal communities at five sites along an elevation gradient from 580 to 980 m above sea level (asl) in the Ziquejie Mountain at the seedling, heading, and mature stages, using high-throughput Illumina sequencing methods. The results revealed that the dominant bacterial phyla were Proteobacteria, Actinobacteria, and Bacteroidetes, and the dominant fungal phyla were Ascomycota and Basidiomycota, which varied significantly at different elevation sites and growth stages. Elevation had a greater effect on the α diversity of phyllosphere bacteria than on that phyllosphere fungi. Meanwhile, the growth stage had a great effect on the α diversity of both phyllosphere bacteria and fungi. Our results also showed that the composition of bacterial and fungal communities varied significantly along elevation within the different growth stages, in terms of both changes in the relative abundance of species, and that the variations in bacterial and fungal composition were well correlated with variations in the average elevation. A total of 18 bacterial and 24 fungal genera were significantly correlated with elevational gradient, displaying large differences at the various growth stages. Soluble protein (SP) shared a strong positive correlation with bacterial and fungal communities (p < 0.05) and had a strong significant negative correlation with Serratia, Passalora, unclassified_Trichosphaeriales, and antioxidant enzymes (R > 0.5, p < 0.05), and significant positive correlation with the fungal genera Xylaria, Gibberella, and Penicillium (R > 0.5, p < 0.05). Therefore, it suggests that elevation and growth stage might alter both the diversity and abundance of phyllosphere bacterial and fungal populations.

In this study, the characteristic of three transformants named as B1C106-1, B1C106-2, and B1C106-3 were studied that carried three innate resistant genes Bph14, Bph15, and Xa23, and two enthetic resistant genes Cry1Ca# and Bar. The five resistant genes were all verified by PCR and the two enthetic genes were identified in single copy insertion by Southern blot. At tillering stage, the Cry1C and PAT (phosphinothricin acetyl transferase) protein contents in leaf, sheath, and stem of T2 generation were in the similar pattern: leaf>stem>sheath, and showed significant difference (P

In our previous study, an early season rice restorer line B2A68 expressing Cry2Aa# gene was obtained. In order to evaluate the performance of B2A68’s hybrids, a total of six hybrids from crossing B2A68 with six thermo-sensitive genic male sterile (TGMS) lines of early season rice were compared for expression level of Cry2Aa protein, as well as in insect resistance, agronomic traits and grain quality with their non-Bt null controls. Our results showed that the highest Cry2Aa protein content among B2A68's hybrids was detected in leaf, where the Cry2Aa content was nearly three times of that in stem. The Cry2Aa content of B2A68 was significantly higher than those of its derived hybrids, indicating the Cry2Aa# gene was incompletely dominant in hybrids. The hybrids with Cry2Aa# gene exhibited higher plant protection against rice leaf roller than the hybrids without Cry2Aa# gene in field. Significant differences were observed in plant height, panicle length, number of grains per panicle, seed set, 1000-grain weight and yield per plant between hybrids with Cry2Aa# gene and hybrids without Cry2Aa# gene in 2013 or 2014. There were significant differences in chalky grain rate and chalkiness degree between paternal lines B2A68 and D68, and between hybrids with Cry2Aa# gene and hybrids without Cry2Aa# gene. All of the differences in agronomic traits and grain quality varied among parental lines and hybrids. In this paper, three hybrids with high lepidopteran resistance, high yield, elite agronomic traits and acceptable grain quality was selected out, that could serve as elite resistant hybrids to control lepidopteran pests in early season rice production.