ZmNRT1.1B (ZmNPF6.6) determines nitrogen use efficiency via regulation of nitrate transport and signalling in maize.

Nitrate (NO ) is crucial for optimal plant growth and development and often limits crop productivity under low availability. In comparison with model plant Arabidopsis, the molecular mechanisms underlying NO acquisition and utilization remain largely unclear in maize. In particular, only a few genes have been exploited to improve nitrogen use efficiency (NUE).

Involvement of a truncated MADS-box transcription factor ZmTMM1 in root nitrate foraging.

Plants can develop root systems with distinct anatomical features and morphological plasticity to forage nutrients distributed heterogeneously in soils. Lateral root proliferation is a typical nutrient-foraging response to a local supply of nitrate, which has been investigated across many plant species. However, the underlying mechanism in maize roots remains largely unknown.

Increased biomass accumulation in maize grown in mixed nitrogen supply is mediated by auxin synthesis.

The use of mixed nitrate and ammonium as a nitrogen source can improve plant growth. Here, we used metabolomics and transcriptomics to study the underlying mechanisms. Maize plants were grown hydroponically in the presence of three forms of nitrogen (nitrate alone, 75%/25% nitrate/ammonium, and ammonium alone).

Phylogenetic, expression and functional characterizations of the maize NLP transcription factor family reveal a role in nitrate assimilation and signaling.

Although nitrate represents an important nitrogen (N) source for maize, a major crop of dryland areas, the molecular mechanisms of nitrate uptake and assimilation remain poorly understood. Here, we identified nine maize NIN-like protein (ZmNLP) genes and analyzed the function of one member, ZmNLP3.1, in nitrate nutrition and signaling.

Comparative Analysis of Root Traits and the Associated QTLs for Maize Seedlings Grown in Paper Roll, Hydroponics and Vermiculite Culture System.

Root system architecture (RSA) plays an important role in the acquisition of both nitrogen (N) and phosphorus (P) from the environment. Currently RSA is rarely considered as criteria for selection to improve nutrient uptake efficiency in crop breeding. Under field conditions roots can be greatly influenced by uncontrolled environment factors.

Arabidopsis formin3 directs the formation of actin cables and polarized growth in pollen tubes.

Cytoplasmic actin cables are the most prominent actin structures in plant cells, but the molecular mechanism underlying their formation is unknown. The function of these actin cables, which are proposed to modulate cytoplasmic streaming and intracellular movement of many organelles in plants, has not been studied by genetic means. Here, we show that Arabidopsis thaliana formin3 (AFH3) is an actin nucleation factor responsible for the formation of longitudinal actin cables in pollen tubes.

Heterosis in root development and differential gene expression between hybrids and their parental inbreds in wheat (Triticum aestivum L.).

In spite of commercial use of heterosis in agriculture, the molecular basis of heterosis is poorly understood. In this study, heterosis was estimated for eight root traits in 20 wheat hybrids derived from a NC Design II mating scheme. Positive mid-parent heterosis was detected in 96 of 160 hybrid-trait combinations, and positive high-parent heterosis was detected in 79 of 160 hybrid-trait combinations.

Relationship between differences of gene expression in early developing seeds of hybrid versus parents and heterosis in wheat.

In order to understand molecular basis of heterosis, mRNA differential display was used to analyze the differences in gene expression between seeds of 18 reciprocal hybrids and their 6 parents at 6th day after pollination. The relationship between gene expression patterns and heterosis was determined. Only bands that can be repeated in duplicate PCR were used for analysis so as to reduce false positive bands.