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Oryza sativa PHOSPHATE RESPONSE2 (OsPHR2) can promote the uptake and use of phosphorus (P) in rice. We introduced OsPHR2 into the winter wheat (Triticum aestivum L.) variety "Zhengmai0856." OsPHR2 was integrated into the wheat genome with two copy numbers and could be correctly transcribed and expressed. OsPHR2 was mainly expressed in the leaves at the seedling stage. From the jointing to filling stage, OsPHR2 was mainly expressed in the roots, followed by the leaves, with a low expression level in detected the tassels and stems. The transgenic lines exhibited higher P accumulation at each growth stage and increased P uptake intensity in comparison to the wild type under low P and high P conditions. Analysis of the root characteristics showed that the transgenic expression of OsPHR2 increased the maximum root length, total root length, root-to-shoot ratio, and root volume under the conditions of P deficiency or low P. A field experiment showed that the transgenic lines had a higher grain yield than the wild type under low P and high P conditions. The yield of the transgenic lines increased by 6.29% and 3.73% on average compared with the wild type under low P and high P conditions, respectively. Thus, the transgenic expression of OsPHR2 could increase P uptake and yield in wheat, but the effect was more prominent under low P conditions. [ABSTRACT FROM AUTHOR]

Lodging is one of the most important factors that reduce wheat grain yields. To improve lodging resistance, increasing the strength of wheat stems has been an important breeding objective. To assess the rate of genetic improvement of the character, 30 wheat accessions, varying from landraces to cultivars that have been widely grown in Henan Province, China during the last 70 years, were tested for several parameters of lodging resistance in a two-year experiment. Stem strength, morphological and anatomical traits, and chemical composition were measured. The results showed that stem strength, both at anthesis and 25 days thereafter, has increased significantly during this period with average annual genetic gains of 1.07 and 0.87 %, respectively. Compared with older wheat cultivars, stem walls of modern cultivars are thicker, and the lignin content is higher. Grain yield has been significantly increased over the last 70 years, and the results of multiple regression analysis indicated that the genetic improvement of grain yield was associated with the increase in stem strength and the decrease in plant height. [ABSTRACT FROM AUTHOR]

Enhancing drought tolerance of crops has been a great challenge in crop improvement. Here, we report the maize phosphoenolpyruvate carboxylase ( PEPC) gene was able to confer drought tolerance and increase grain yield in transgenic wheat ( Triticum aestivum L.) plants. The improved of drought tolerance was associated with higher levels of proline, soluble sugar, soluble protein, and higher water use efficiency. The transgenic wheat plants had also a more extensive root system as well as increased photosynthetic capacity during stress treatments. The increased grain yield of the transgenic wheat was contributed by improved biomass, larger spike and grain numbers, and heavier 1000-grain weight under drought-stress conditions. Under non-stressed conditions, there were no significant increases in these of the measured traits except for photosynthetic rate when compared with parental wheat. Proteomic research showed that the expression levels of some proteins, including chlorophyll A-B binding protein and pyruvate, phosphate dikinase, which are related to photosynthesis, PAP fibrillin, which is involved in cytoskeleton synthesis, S-adenosylmethionine synthetase, which catalyzes methionine synthesis, were induced in the transgenic wheat under drought stress. Additionally, the expression of glutamine synthetase, which is involved in ammonia assimilation, was induced by drought stress in the wheat. Our study shows that PEPC can improve both stress tolerance and grain yield in wheat, demonstrating the efficacy of PEPC in crop improvement. [ABSTRACT FROM AUTHOR]