藜麦种子萌发阶段响应干旱和盐胁迫变化的综合评价

随着我国藜麦产业不断发展和利用边际性土地种植规模的扩大,藜麦种子萌发阶段对干旱和盐胁迫的响应研究越来越受到重视。本文采用室内PEG-6000模拟干旱胁迫和NaCl模拟盐胁迫,通过测定发芽率、发芽势、长度和鲜重等8个指标,对5个藜麦品种(系)(‘南非2号’‘陇藜1号’‘陇藜4号’、HTH-y605、HTH-01)种子萌发期对干旱和盐胁迫的响应进行综合评价研究,并利用主成分分析方法评价藜麦的抗旱性和耐盐性,指出抗旱性和耐盐性的主要评价指标。结果表明:在藜麦萌发阶段抗旱性综合评价中,主成分分析将8个指标归类为2个成分因子,各成分分别以相对长度和相对发芽率载荷量最大,可作为藜麦萌发期抗旱性主要鉴定指标。抗旱性强弱顺序为:‘南非2号’HTH-01‘陇藜4号’‘陇藜1号’HTH-y605。在其耐盐性综合评价中,通过主成分分析将8个指标归类为3个成分因子,相对长度、相对发芽率和相对发芽指数分别为各成分因子上最大的载荷,可以作为藜麦萌发期耐盐性的主要鉴定指标,耐盐性强弱顺序为:HTH-01HTH-y605‘陇藜4号’‘陇藜1号’‘南非2号’。相关性分析结果显示,不同藜麦品种萌发阶段抗旱性与耐盐性之间无明显相关性。研究发现藜麦不同品种在抗旱性和耐盐性具有遗传多样性,其机制有待进一步研究。研究结论对藜麦抗逆机理研究和品种选育有一定的参考价值,为当前中低产田开发利用提供了理论和数据支持。     

藜麦在中国的适应性种植及发展展望

为了了解藜麦在中国地区的发展现状,本研究归纳了藜麦的植物学特性和营养价值,分析了国内藜麦产业存在的种质资源匮乏、种质创新应用不足、高产栽培技术尚未成熟等问题,并提出了提高藜麦产业投入、促进产业多形式发展的发展对策,为藜麦在中国的推广种植和产业发展提供理论参考。     

体外产气法评价全株藜麦与全株玉米混合青贮饲料饲用价值

为提高全株藜麦的饲料化利用率，寻找其与全株玉米的最佳青贮比，试验共设全株藜麦与全株玉米比为100：0，90：10，80：20等11个组合进行青贮发酵，发酵60 d后测定各组青贮料的体外产气发酵指标，使用灰色关联度分析筛选出最佳青贮比例。结果表明，体外发酵至36 h时，各处理组GP趋于稳定，体外发酵减弱接近停止；全株藜麦与全株玉米比例为90：10时，该青贮饲料组合的粗蛋白（CP）和粗脂肪（EE）含量显著高于其他各组（P<0.05），乙酸（AA）、总挥发性脂肪酸（TVFA）含量以及氨态氮（NH₃-N）浓度显著高于其他各处理（P<0.05）。分析表明，全株藜麦与全株玉米比例为90：10时，混合青贮饲料的营养品质和产气发酵特性综合表现最好，可作为优质混合青贮饲料在家畜养殖中推广使用。     

Light interception and radiation use efficiency in temperate quinoa (Chenopodium quinoa Willd.) cultivars

Sea level quinoas are grown at low altitudes in Central and Southern Chile. Both sensitivity to photoperiod and response to temperature largely determine quinoa adaptation, but crop biomass production must be quantified to evaluate agronomic performance. The objectives of this work are: (i) to characterize development effects on leaf area evolution for genotypes of sea level quinoa differing in cycle length, (ii) to quantify the extinction coefficient (k) for photosynthetically active radiation (PAR) and radiation use efficiency (RUE) from emergence up to the beginning of grain filling and (iii) to identify which crop attributes related to canopy architecture should be considered to improve biomass production. Four cultivars (NL-6, RU-5, CO-407 and Faro) were cropped in Pergamino (33°56′S, 60°35′W, 65 m a.s.l.), Argentina, at three densities (from 22 to 66 plants m⁻²) in two consecutive years under field conditions with adequate water and nutrient supply. Thermal time to first anthesis and maximum leaf number on the main stem were linearly correlated (r² = 0.87; p < 0.0001). Leaf area continued to increase during the flowering phase, notably in NL-6, the earliest genotype. There were significant differences in maximum plant leaf area between cultivars. Increasing density reduced plant leaf area but effects were comparatively small. Estimated k was 0.59 ± 0.02 across genotypes and was higher (p < 0.05) for 66 plants m⁻². Values for RUE changed as cumulative intercepted PAR (IPAR) increased; at initial stages of development RUE was 1.25 ± 0.09 g MJ IPAR⁻¹, but if cumulative IPAR was higher than 107.5 ± 10.4 MJ IPAR m⁻², RUE was 2.68 ± 0.15 g MJ IPAR⁻¹. That change occurred when leaf area index (LAI) and fraction of PAR intercepted were still low and ranged from 0.61 to 1.38 and from 0.33 to 0.51, respectively. No significant association was found with any developmental stage. Our results agreed to the notion that RUE variation during pre-anthesis phases is largely determined by LAI through its effect on radiation distribution within the canopy. Biomass production could be improved if periods of interception below 50% of incoming PAR were reduced to ensure high RUE. This seems to be possible in temperate areas both by the use of late genotypes with a higher number of leaves on the main stem and by early genotypes provided adequate plant density is chosen. Early increment in LAI and overlapping of the leaf area increase period with the flowering phase are desirable strategies for earliest genotypes to maximize yield.     

Effect of quinoa flour on gluten-free bread batter rheology and bread quality

A new gluten-free bread formulations composed of quinoa, buckwheat, rice flour and potato starch were developed in the present study. Rheological characteristics of the bread batter with increasing amount of quinoa were determined; storage (G′) and loss modulus (G″) values were also measured for investigation of viscoelastic properties. To evaluate the quality of breads; technological and physical (bake loss %, specific volume, texture, microstructure, color), chemical (protein, moisture, ash) and sensory properties were determined. All batter formulations independent of the quinoa amount exhibited pseudoplastic behavior, and G′ values were found to be higher than G″ values in expressing the solid like characteristics of the batter. Amount of quinoa flour addition did not present significant difference on bake loss%, specific volume and protein content (p>0.05); however, 25% quinoa flour bread displayed better results with its higher sensory scores and softer texture. Quinoa and buckwheat flour mixture therefore will be a good alternative for conventional gluten-free bread formulations.     

EFFECT OF MIXED-SALT SALINITY ON GROWTH AND ION RELATIONS OF A QUINOA AND A WHEAT VARIETY

ABSTRACT

Salinity is among the most widespread and prevalent problems in irrigated agriculture. Many members of the family Chenopodiaceae are classified as salt tolerant. One member of this family, which is of increasing interest, is quinoa (Chenopodium quinoa Willd.) which is able to grow on poorer soils. Salinity sensitivity studies of quinoa were conducted in the greenhouse on the cultivar, “Andean Hybrid” to determine if quinoa had useful mechanisms for salt tolerant studies. For salt treatment we used a salinity composition that would occur in a typical soil in the San Joaquin Valley of California using drainage waters for irrigation. Salinity treatments (EC_i ) ranging from 3, 7, 11, to 19?dS?m^?1 were achieved by adding MgSO₄, Na₂SO₄, NaCl, and CaCl₂ to the base nutrient solution. These salts were added incrementally over a four-day period to avoid osmotic shock to the seedlings. The base nutrient solution without added salt served as the non-saline control solution (3?dS?m^?1). Solution pH was uncontrolled and ranged from 7.7 to 8.0. For comparative purposes, we also examined Yecora Rojo, a semi-dwarf wheat, Triticum aestivum L. With respect to salinity effects on growth in quinoa, we found no significant reduction in plant height or fresh weight until the electrical conductivity exceeded 11?dS?m^?1. The growth was characteristic of a halophyte with a significant increase in leaf area at 11?dS?m^?1 as compared with 3?dS?m^?1 controls. As to wheat, plant fresh and dry weight, canopy height, and leaf area did not differ between controls (3?dS?m^?1) and plants grown at 7?dS?m^?1. Beyond this threshold, however, plant growth declined. While both quinoa and wheat exhibited increasing Na⁺ accumulation with increasing salinity levels, the percentage increase was greater in wheat. Examination of ion ratios indicated that K⁺:Na⁺ ratio decreased with increasing salinity in both species. The decrease was more dramatic in wheat. A similar observation was also made with respect to the Ca²⁺:Na⁺ ratios. However, a difference between the two species was found with respect to changes in the level of K⁺ in the plant. In quinoa, leaf K⁺ levels measured at 19?dS?m^?1 had decreased by only 7% compared with controls. Stem K⁺ levels were not significantly affected. In wheat, shoot K⁺ levels had decreased by almost 40% at 19?dS?m^?1. Correlated with these findings, we measured no change in the K⁺:Na⁺ selectivity with increasing salinity in quinoa leaves and only a small increase in stems. In wheat however, K⁺:Na⁺ selectivity at 3?dS?m^?1 was much higher than in quinoa and decreased significantly across the four salinity levels tested. A similar situation was also noted with Ca²⁺:Na⁺ selectivity. We concluded that the greater salt tolerance found in quinoa relative to wheat may be due to a variety of mechanisms.     

南美藜种子蛋白质研究

以西藏产南美藜Ｍ１为材料，对其种子蛋白质进行了研究，结果表明，南美藜种子蛋白质含量较高，达１５．５７％，富含赖氨酸（５．７１％），精氨酸（１０．０６％）等碱性氨基酸及天冬氨酸（７．６３％），谷氨酸（１１．６３％）等酸性氨基酸，种子蛋白质各组中心清蛋白（８．３６％）为主，占蛋白质总量的５３．６９％，南美藜种子总蛋白主要由６９，６６，５５，５２，５０，４１，３９，３６，３５，３２，２３，１８，１４，１     

永昌县藜麦种植的适宜性及存在的问题

为掌握藜麦在永昌的适宜性和种植过程中存在的问题,整理2017—2019年永昌藜麦生育期资料,结合气象资料和土壤养分实测资料,用对比分析法分析藜麦的生育期与气象条件之间的关系和造成藜麦减产的原因。结果表明：永昌藜麦全生育期为139天,整个生育期内所需的平均积温为2363.9℃,4月下旬是藜麦的最佳播种期;种植藜麦后的土地,氮、磷、钾的减少幅度较大,对耕地质量存在不良影响;播期推迟、连阴雨天气、种植土地未进行倒茬都是造成藜麦减产的原因;藜麦的种植要根据当地的实际情况因地制宜。     

Use of amaranth,quinoa and kañiwa in extruded corn-based snacks

Amaranth (Amaranthus caudatus), quinoa (Chenopodium quinoa) and kañiwa (Chenopodium pallidicaule) are pseudocereals regarded as good gluten-free sources of protein and fiber. A co-rotating twin screw extruder was used to obtain corn-based extrudates containing amaranth/quinoa/kañiwa (20% of solids). Box–Behnken experimental design with three independent variables was used: water content of mass (WCM, 15–19%), screw speed (SS, 200–500 rpm) and temperature of the die (TEM, 150–170 °C). Milled and whole samples were stored in open headspace vials at 11 and 76% relative humidity (RH) for a week before being sealed and stored for 9 weeks in the dark. Hexanal content was determined by using headspace gas chromatography. Extrudates containing amaranth presented the highest sectional expansion index (SEI) (p < 0.01) while pure corn extrudates (control) presented the lowest SEI and greatest hardness (p < 0.01). SEI increased with increasing SS and decreasing WCM. In storage, whole extrudates exposed to 76% RH presented the lowest formation of hexanal. This study proved that it was possible to increase SEI by adding amaranth, quinoa and kañiwa to pure corn flour. The evaluation of lipid oxidation suggested a remarkable stability of whole extrudates after exposure to high RH.     

盐胁迫对藜麦种子萌发特性的影响

[目的]研究不同浓度盐胁迫对藜麦种子萌发特性的影响。[方法]对不同浓度NaCl处理下藜麦种子的各项发芽指标进行差异分析。[结果]随着NaCl浓度的增加,藜麦种子的初始发芽时间和萌发高峰均随之推迟,发芽率、发芽势、发芽指数、活力指数、根长、苗高及幼苗鲜重均呈逐渐下降的趋势,而相对盐害率逐渐升高。1.0%的NaCl胁迫下,藜麦种子的发芽率、发芽势、活力指数、相对盐害率及根长与对照相比差异不显著;当NaCl浓度高于2.0%时,藜麦种子的发芽率、发芽势、发芽指数、活力指数、根长、苗高及幼苗鲜重均显著低于对照,而相对盐害率显著高于对照;3.0%盐胁迫下种子萌发完全受到抑制。[结论]藜麦能在01.0%的盐浓度范围内生长良好,是一种高耐盐作物。该研究结果可为藜麦在盐碱地的开发利用和耐盐作物新品种选育提供参考。