Genotypic Variation in Growth and Physiological Response to Drought Stress and Re-Watering Reveals the Critical Role of Recovery in Drought Adaptation in Maize Seedlings.

Non-irrigated crops in temperate climates and irrigated crops in arid climates are subjected to continuous cycles of water stress and re-watering. Thus, fast and efficient recovery from water stress may be among the key determinants of plant drought adaptation. The present study was designed to comparatively analyze the roles of drought resistance and drought recovery in drought adaptation and to investigate the physiological basis of genotypic variation in drought adaptation in maize (Zea mays) seedlings.

Biomass allocation, relative competitive ability and water use efficiency of two dominant species in semiarid Loess Plateau under water stress.

A better understanding of the growth and interspecific competition of native dominant species under water stress should aid in prediction of succession in plant communities. In addition, such research would guide the selection of appropriate conservation and agricultural utilization of plants in semiarid environments that have not been very well characterized. Biomass production and allocation, relative competitive ability and water use efficiency of one C(4) herbaceous grass (Bothriochloa ischaemum) and one C(3) leguminous subshrub (Lespedeza davurica), both important species from the semiarid Loess Plateau of China, were investigated in a pot-cultivation experiment.

Long-term outcomes of percutaneous retrogasserian glycerol rhizotomy in 3370 patients with trigeminal neuralgia.

Aim: To assess the long-term outcomes of percutaneous retrogasserian glycerol rhizotomy (PRGR) in patients with medically unresponsive idiopathic trigeminal neuralgia.

Material And Methods: A total of 3370 patients undergoing PRGR between 1983 and 2003 in our hospital were followed up for 13.1 years (range 3-23 years), and the outcomes were investigated.

Seedling biomass partition and water use efficiency of switchgrass and milkvetch in monocultures and mixtures in response to various water availabilities.

Seedling biomass and allocation, transpiration water use efficiency (TWUE), and species competition between switchgrass (Panicum virgatum L.) and milkvetch (Astragalus adsurgens Pall.) were investigated in a pot-cultivated experiment under different levels of water availability.

[Comparison of ecophysiological characteristics of seven plant species in semiarid loess hilly-gully region].

The diurnal course of photosynthetic rate, transpiration rate, and leaf water potential (psi L) of five plant species in North Shaanxi loess hilly-gully region were measured in dry seasons. Based on the daily maximum photosynthetic and transpiration rates, daily total assimilation and transpiration, and diurnal change characteristics of psi L, the test plants were classified into different eco-adaptation types. Panicum virgatum L.

Secondary succession and its effects on soil moisture and nutrition in abandoned old-fields of hilly region of Loess Plateau, China.

Floristic composition, community structure and soil moisture and nutrient contents in abandoned fields of different ages were analyzed to clarify the regenerative aspects of succession as a tool for vegetation restoration. The results indicated that secondary succession in this region can be interpreted as an auto-succession: there are main changes in species-relative abundance and species turnover. Annual or biennial species (e.

[Expression of ZmPIP1 subgroup genes in maize roots under water shortage].

To investigate the role of ZmPIP1-1 and ZmPIP1-2 in water uptake of roots and drought resistance of crops, semi-quantitative PCR was used to examine the expression of ZmPIP1-1 and ZmPIP1-2 in root systems of different maize genotypes under water deficit. These genotypes showed different resistance to water shortage under field conditions. The reference gene to target genes was tubulin.

[Responses of Medicago sativa and Astragalus adsurgens seedlings growth and water use to soil moisture regime].

In the semi-arid area of Loess Plateau, seasonal drought often occurs during the vegetative stage of grass plants, leading to the subsequent serious reduction of their yield. Aimed to study the responses of the seedlings growth and water use of two perennial leguminous grasses Medicago sativa and Astragalus adsurgens to different soil moisture regimes, a pot experiment was installed with five treatments, i.e.

[Effects of osmotic stress on chlorophyll fluorescence parameters of wheat seedling].

By using chlorophyll fluorescence kinetics technology, this paper determined the chlorophyll fluorescence parameters Fv/Fm, phiPSII, qP, qNP, ETR of winter wheat seedling under simulated osmotic stress. The results showed that with the increase of osmotic stress, Fv/Fm and Fv/Fo had the trend of decrease-increase-decrease, indicating that photoinhibition did not happen at the first stage of osmotic stress, but the followed increase of Fv/Fm resulted in the photoinhibition and the decrease of phiPSII and ETR. During the course of osmotic stress, qP and qNP decreased firstly and then increased, which was helpful to enhance the open ratio of PSII reaction center, and made more photosynthetic energy use the photosynthetic electron transport to enhance the electron transport capacity.

Effects of Eu3+ on the metabolism of amino acid and protein in xerophytic Lathyrus sativus L.

The contents of amino acids and proteins and the activity of Na+,K+-ATPase were determined in roots, stems, and leaves of Eu3+-treated Lathyrus sativus L. The results showed that the treatment of Eu3+ made the contents of amino acid and protein and the activity of Na+,K+-ATPase change. The first possible mechanism was that Eu3+ directly made the electric potential of -NH2 or -COOH of amino acid change.

[A comparative study on water use characteristics and eco-adaptability of Hippophae rhamnoides and Caragana korshinskii in semi-arid loess hilly-gully region].

This study compared the seasonal dynamics of soil water content, biomass productivity, and leaf photosynthetic physiology and water potential between about ten years old Hippophae rhamnoides and Caragana korshinskii planted on the hilly slope land of semi-arid loess hilly-gully region. The results showed that there existed dry soil layer in the stands. The seasonal compensation depth of soil water in Hippophae rhamnoides stand was deeper and its water use capability was better than those of C.

[A review on types and mechanisms of compensation effect of crops under water deficit].

In arid and semi-arid regions, the fact that crops suffering water deficit is unavoidable. Many studies indicated that plants have an ability to compensate the adverse effect of drought when the drought is moderate. But, how the compensation effects take place, and what are the physiological and biochemical mechanisms? This paper summarized the types, mechanisms and conditions of compensation effect that crops have under water deficit.

[Effect of soil bulk density on maize growth under different water regimes].

Split-root experiments were conducted with maize under both low (-0.86 MPa) and high (-0.17 MPa) soil matrix potential conditions, in which, maize roots were divided equally between two compartments in partitioned galvanized steel containers containing Lou soil.

[Effect of nitrogen nutrition on endogenous hormone content of maize under soil drought conditions].

It is realized in recent years that roots play an important role in the control of shoot growth and development, not only because they can continuously provide the shoot with water and nutrients, but also because some chemical messengers are produced in roots to response soil drought stress and transported through transpiration stream to shoot where physiological processes are regulated. Extensive studies showed that the decrease of leaf conductance was closely related to the increase of xylem ABA concentration, suggesting that ABA can act as a water stress signal to regulate the physiological response of shoot. Fertilizer plays an important role in increasing crop yield and water use efficiency (WUE) on dry-land farming.

Effect of rare earth element europium on amaranthin synthesis in Amarathus caudatus seedlings.

Considering the resemblances between Eu3+ and Ca2+ in their atomic radius and structures of the valence electron, the effects of Eu3+ on amaramthin synthesis in Amarathus caudatus seedling were studied. Eu3+ had both promoting and inhibiting effects on amaramthin synthesis. The optimum promoting concentration and half inhibiting concentration of Eu3+ to synthesis of amaranthin were 0.