汞水平对苋菜种子萌发的影响

采用不同浓度的氯化汞溶液(0.5、1.0、2.5、5.0、10.0、25.0、50.0、100.0 mg/L)对不同品种苋菜种子进行浸种处理。结果表明,Hg+对苋菜种子萌发的影响在低浓度时有促进作用,随着Hg+浓度增加,苋菜种子的根长和芽长都明显减少,当Hg+浓度达到100 mg/L时,苋菜种子见萌芽,但都有红褐色痕迹,即汞污染现象非常明显;Hg+较高浓度时,各个不同品种苋菜种子导电率相对较高,种子活力相对较低。     

Genetic basis and origin of resistance to acetolactate synthase inhibitors in Amaranthus palmeri from Spain and Italy

BACKGROUND

Amaranthus palmeri is an aggressive annual weed native to the United States, which has become invasive in some European countries. Populations resistant to acetolactate synthase (ALS) inhibitors have been recorded in Spain and Italy, but the evolutionary origin of the resistance traits remains unknown. Bioassays were conducted to identify cross-resistance to ALS inhibitors and a haplotype-based genetic approach was used to elucidate the origin and distribution of resistance in both countries.

RESULTS

Amaranthus palmeri populations were resistant to thifensulfuron-methyl and imazamox, and the 574-Leu mutant ALS allele was found to be the main cause of resistance among them. In two Spanish populations, 376-Glu and 197-Thr mutant ALS alleles were also found. The haplotype analyses revealed the presence of two and four distinct 574-Leu mutant haplotypes in the Italian and Spanish populations, respectively. None was common to both countries, but some mutant haplotypes were shared between geographically close populations or between populations more than 100 km apart. Wide genetic diversity was found in two very close Spanish populations.

CONCLUSION

ALS-resistant A. palmeri populations were introduced to Italy and Spain from outside Europe. Populations from both countries have different evolutionary histories and originate from independent introduction events. ALS resistance then spread over short and long distances by seed dispersal. The higher number and genetic diversity among mutant haplotypes from the Spanish populations indicated recurrent invasions. The implementation of control tactics to limit seed dispersal and the establishment of A. palmeri is recommended in both countries. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Transpiration efficiency of Amaranth (Amaranthus sp.) in response to drought stress

Drought is a major abiotic stress responsible for severe crop losses worldwide. Development of new crop varieties with increased drought tolerance is one way to increase crop productivity. The aim of this study was to characterise the diversity of nine accessions belonging to Amaranthus tricolor and A. cruentus, in response to drought stress using a dry-down protocol to characterise the transpiration efficiency (TE). Plants were subjected to either a gradual dry down or well-watered conditions. Results showed that TE was significantly higher (P < 0.01) in water-deficient (WD) plants compared to water-sufficient (WS) plants, 2.40 g kg^?1–7.13 g kg^?1 and 2.19 g kg^?1–4.84 g kg^?1, respectively. There was no significant difference in the fraction of transpirable soil water (FTSW) threshold decline between the amaranth genotypes. TE was highly correlated with yield under both WS (r = 0.89, P < 0.001) and WD conditions (r = 0.662, P < 0.001), and negatively correlated with root-to-shoot ratio under both WS (r = ?0.488, P < 0.05) and WD conditions (r = ?0.460, P < 0.05). Significant genotypic differences were seen for growth rate and stress susceptibility index (SSI). The result obtained in this investigation underline the need to identify genotypic variation in water use efficiency in amaranth.

Abbreviations: FTSW: Fraction of transpirable soil water; NTR: normalised transpiration rate; SSI: Stress susceptibility index; TE: transpiration efficiency; WHC: water holding capacity; WD: water-deficient; WS: water-sufficient.     

Male-sterility in the grain amaranth (Amaranthus hypochondriacus ex-Nepal) variety Jumla

Summary Twenty naturally occurring male-sterile plants were recovered from a normal population of the grain amaranth, variety Jumla. The identification of the male-sterile plants is possible during anthesis and after flowering. The male-sterility in this variety is conditioned by a single recessive nuclear gene ms.This research was supported by Grant No. AMA-KE-4-83-22 (CRG GRANT) from the National Academy of Science, USA. Reprint requests to V.K. Gupta.     

苋菜试管开花初探

以苋菜试管苗为材料,研究多种因子对苋菜试管开花的影响.结果表明:(1)基本培养基MS和1/2MS对苋菜试管开花的影响不大.(2)单独添加NAA,可促进苋菜试管开花；苋菜试管开花对IBA含量的变化较敏感；6-BA含量为1.0 mg.L-1时的开花率最高,培养50 -60 d时可达58.7％.(3)不同单色光处理时,绿光与...     

赤霉素对苋菜产量和营养品质的影响及其残留研究

探索赤霉素对苋菜产量和品质的影响以及残留动态,为建立苋菜生产中赤霉素安全、有效使用技术规程提供科学依据。[方法]广州地区夏季苋菜生长到5-6片真叶时,叶面喷施高(90 g/hm2)、中(60g/ hm2)、低(30 g/hm2)三种浓度赤霉素,喷施后测定不同时期的苋菜株高、产量以及维生素C、蛋白质、还原糖、可溶性固形物、粗纤维含量,研究不同剂量赤霉素对株高、产量、营养品质的影响;测定苋菜不同生长期赤霉素残留,获得残留动态以及最终残留。 [结果]中剂量赤霉素处理对株高和产量促进作用显著,喷施后3-10 d样品的平均株高比对照增加11.50 %,平均产量增加27.56 %,达显著水平。其中3、5、7 d样品株高比对照增加达显著水平,分别为10.59%、13.33%、12.71%;5、7、10 d样品产量比对照增加达显著水平,分别为33.41%、44.35%、17.41%。低剂量和中剂量处理后10 d样品中维生素C含量分别比对照增加67.44 %、44.50 %,达显著水平;蛋白质含量分别比对照组增加12.17 %、11.11 %,达显著水平。三种剂量处理后10 d后样品还原糖、粗纤维及可溶性固形物含量与对照组均无显著差异。赤霉素降解动态曲线符合一级动力方程,半衰期为1.24 d;三种剂量处理后5、7、10 d苋菜赤霉素最终残留均值在0.0012-0.0074 mg/kg之间(定量限只到0.01;有效数字过多),远低于日本限量标准0.2 mg/kg。 [结论] 广州地区夏季苋菜生长到5-6片真叶时,叶面喷施60 g/hm2的赤霉素溶液,喷施后10 d采收,赤霉素残留均值为0.002mg/kg,产量比对照增加17.41%,维生素C含量增加44.50%,蛋白质含量增加11.11%,可溶性固形物、还原糖、粗纤维含量差异不显著。建议可用日本肯定列表中的残最大留限量作为广州地区中国苋菜上赤霉素的残留限量标准。     

水稻和不同品种苋菜间作对水稻产量、根区速效养分及砷累积的影响

【目的】探究水稻与苋菜间作对水稻产量、根区速效养分及水稻各部位吸收累积As的影响。【方法】通过小区试验研究水稻单作(对照)、水稻与圆叶白苋菜间作、水稻与籽粒苋间作、水稻与红苋菜间作条件下水稻产量、根际土壤速效养分与有机质含量、As累积量的变化。【结果】4个处理水稻收获期地上部、地下部、谷壳和糙米中As含量均表现为:水稻与圆叶白苋菜间作水稻与籽粒苋间作水稻与红苋菜间作水稻单作。与对照相比,水稻与圆叶白苋菜间作显著提高了水稻地上部、地下部、谷壳和糙米As含量,增幅分别为88.50%、65.38%、68.25%和45.45%;对土壤As的提取量为5.44 mg·m~(-2),显著高于对照,为对照的1.67倍;水稻单株生物量显著高于对照、与红苋菜间作和与籽粒苋间作,地上部生物量比对照提高63.79%。与水稻单作相比,间作处理水稻单位面积产量比对照显著下降,间作中单位面积产量最高的为与圆叶白苋菜间作,为对照的59.15%;间作处理水稻根际土壤速效养分、有机质含量均有不同程度的增加。【结论】水稻与苋菜间作,水稻单位面积产量降低,地上部、地下部、谷壳和糙米中As含量以及根区土壤速效养分与有机质含量显著提高。水稻与圆叶白苋菜间作能从As污染土壤中提取最多的As,生产出的苋菜符合国家安全标准,为最优方案。     

籽粒苋的应用研究进展

对近10年国内外籽粒苋在饲料、食品、功能性食品和药品等方面的应用进行了归纳总结,发现目前对于籽粒苋的应用主要集中在饲料、食品的粗加工方面,其食用价值基本未开发,应加大籽粒苋在功能性和食品方面的应用,使其作为新型的食品资源加以开发利用。