No abstract

Suaeda rigida is a lignified, true haplotype that predominantly grows in the Tarim basin, China. It has significant economic and ecological value. Herein, with aim to determine the genes associated with salt tolerance, transcriptome sequencing was performed on its stem, leaves and root over three set NaCl gradients regimens at treatment intervals of 3 h and 5 days. From our findings, we identified 829,095 unigenes, with 331,394 being successfully matched to at least one annotation database. In roots, under 3 h treatment, no up-regulated DEGs were identified in 100 and 500 mM NaCl treated samples. Under 5 days treatment, 97, 60 and 242 up-regulated DEGs were identified in 100, 300, 500 mM NaCl treated samples, respectively. We identified 50, 22 and 255 down-regulated DEGs in 100, 300, 500 mM NaCl treated samples, respectively. GO biological process enrichment analysis established that down-regulated DEGs were associated with nitrogen compound transport, organic substance transport and intracellular protein transport while the up-regulated genes were enriched in cell wall biogenesis, such as plant-type cell wall biogenesis, cell wall assembly, extracellular matrix organization and plant-type cell wall organization. These findings provide valuable knowledge on genes associated with salt tolerance of Suaeda rigida, and can be applied in other downstream haplotype studies.

Water shortage is a serious problem threatening sustainable development of agriculture in the North China Plain, where winter wheat is the largest water-consuming crop. The objective of this study was to optimize irrigation scheme for high yield and high water use efficiency (WUE) in wheat (Triticum aestivum L.), on the basis of Jimai 22, a represented cultivar in production. In the field experiments conducted in growing seasons, unfixed amount of water was supplied at sowing, jointing, and anthesis stages to adjust the soil moisture into a controlled ladder. For example, the relative soil moisture contents in the W0 treatment were 85% at sowing, 80% at jointing, and 70% at anthesis; in the W1 treatment, they were 85%, 85%, and 70%, respectively; analogically, they were 85%, 85%, and 75% in the W2 treatment and 85%, 90%, and 80% in the W3 treatment. The results showed that WUE was higher in W0 than in other treatments. However, the grain yield was the lowest in treatment W0. In growing seasons, the grain yield, irrigation water use efficiency (WUEI), precipitation use efficiency (WUEP), and irrigation benefit (IB) in W1, W2, and W3 were decreased significantly because more water was supplied. Under the experimental condition, the W1 regime was considered as the optimum. In this regime, the relative soil moisture contents at 0–140 cm soil layer were controlled to 85% at sowing, 80% at jointing, and 70% at anthesis stages. When 15.32 mm of water was supplied in growing seasons, the final grain yields of W1 treatment were 8185.75 kg ha-1, and the WUEI and WUEP were the highest among the 4 treatments. The deep soil water content (0-140 cm) can be estimated by shallow soil moisture content (0-60 cm), which is more conducive to estimate the deep soil water content through shallow soil and reduce the workload of supplemental irrigation based on testing soil moisture.

Water shortage is a serious problem threatening sustainable agricultural development in the North China Plain (NCP), where winter wheat (Triticum aestivum L.) is the largest water-consuming crop. Water-saving technique is one of the most important components in wheat cultivation system in this area. The purpose of this study was to optimize irrigation scheduling for high yield and water use efficiency (WUE) in wheat. Unlike earlier studies in which fixed irrigation amounts were given, we designed a ladder of relative soil moisture content at critical growth stages of wheat. The results are expected to provide general and valuable guidelines to farmers and irrigation managers in high-yielding wheat production in the NCP. The field experiments was conducted with the cultivar of Jimai 22 in Shiwang village (35.41°N, 116.41°E), Yanzhou, Shandong, China in 2007-2009 growing seasons. The irrigation treatments were designed based on the contents of relative soil moisture at sowing, jointing, and anthesis stages which were 80%, 65%, and 65% for treatment W0; 80%, 70%, and 70% for treatment W1; 80%, 80%, and 80% for treatment W2; 90%, 80%, and 80% for treatment W3, respectively. The accumulation and distribution of dry matter and water use efficiency (WUE) in wheat plants were investigated subject to soil moisture and supplemental irrigation. The results showed that dry matter accumulation amount in treatment W0 was the lowest whereas that in treatment W1 was the highest at maturity stage. The grain dry matter ratio was significantly higher in treatment W1 than in treatments W2 and W3. After anthesis, the redistribution amount and the ratio of dry matter that stored in vegetative organs before anthesis were presented as W0>W3>W2>W1, and the contribution of dry matter accumulation amount after anthesis to grains as W1>W2>W3>W0. Under