稻米矿质营养元素的研究进展

综述了矿质营养元素在人体中的重要功能以及对稻米矿质营养元素的研究进展,并对今后的研究方向提出一些看法。     

稻米贮藏保鲜研究进展

稻米（Oryza sativa L.）富含丰富的营养物质,是我国重要的口粮,年消费总量约1.2亿t,人均年消费约100 kg。稻米主要食用部分是稻谷的胚乳[1],而稻谷作为水稻的种子[2],贮藏过程中伴随着生理化学变化及物理变化[3],直接影响稻米品质和商品价值[4]。从稻米陈化机理[5]、贮藏和保鲜的监测指标及方法[6]等方面概述了稻米贮藏保鲜的研究现状,比较分析了目前稻米贮藏保鲜技术方法,探讨今后稻米贮藏保鲜的研究方向。     

推进稻米清洁生产提升稻米产业竞争力

本文阐述了我国稻米清洁生产的完整概念、内涵与意义，比较了清洁生产初、中、高三个层次(无公害稻米、绿色食品稻米与有机稻米)的异同，分析了实施清洁生产所面临的主要问题，并提出了相应对策。     

温度对稻米品质影响的研究进展

水稻灌浆期的温度条件是影响稻米品质的主要环境因子。从稻米碾米品质、外观品质、蒸煮食味品质和营养品质四个方面,综述了温度对稻米品质影响的研究进展。     

稻米中香味物质的研究进展

稻米的香味性状是衡量稻米品质好坏的最重要指标之一,本文从稻米香味物质的分离分析方法、稻米香味物质的成分两个角度总结了稻米中香味物质的研究进展,并对稻米中香味物质的研究作出了展望。     

稻米中矿质元素及其测定方法的研究进展

从稻米中矿质元素的含量、分布、对人体健康的影响以及矿质元素含量的测定方法等方面综述了当前关于稻米矿质元素的研究进展,并提出了今后稻米矿质元素理化分析方法及水稻矿质元素营养育种的研究方向。     

国际稻米贸易特点与中国稻米出口

中国加入世界贸易组织 ,给中国稻米产业发展带来了机遇 ,要抓住机遇 ,使中国稻米在国际稻米贸易中的地位得到巩固和发展 ,无论从观念上还是措施上都需要进行创新。特别是要增强我国稻米国际竞争力 ,促进稻米国际贸易的发展。分析２０世纪９０年代世界稻米贸易的特点 ,对指导我国稻米发展具有积极意义。一、世界稻米贸易特点２０世纪９０年代 ,随着世界人口的增加和世界经济的发展 ,全世界对稻米的消费大幅度增长 ,使世界稻米贸易迅速扩大。２０００年世界稻米消耗量达到３．９亿吨 ,比１９９０年增加４９００多万吨 ,增长１４．４%。２００…     

我国稻米产业融合发展的研究进展

在梳理近5年来我国稻米产业融合发展研究文献基础上,总结了稻米产业融合发展的主要模式,从经营主体、服务支撑、科技创新、运行机制、政府政策、品牌建设等方面归纳了目前稻米融合发展中存在的问题及相关的对策建议,提出了现有研究的不足和进一步研究的展望.     

杂交水稻稻米品质遗传与育种研究进展

扼要介绍了稻米品质的概念、要素，评价稻米品质的主要指标，综合评述了稻米品质的研究进展.通过对湖南省优质杂交稻育种的现状与进展分析，结合当前我国水稻品种的品质现状，指出了稻米品质研究中存在的问题.提出了今后稻米品质改良的研究方向。     

栽培措施对稻米品质影响的研究进展

随着生活水平的提高,稻米品质愈发受到人们的关注。本文概述了本世纪以来,我国农业科技工作者在栽培措施对稻米品质影响方面的一些研究成果,并从播期、密度、种植方式、肥料运筹、水分管理和种养模式等方面总结了优质稻米生产技术,供生产者参考。     

Effects of Water Management,Arsenic and Phosphorus Levels on Rice Yield in High-Arsenic Soil-Water System

Aerobic rice （Oryza sativa L.） cultivation is considered an alternative production system to combat increased water scarcity and arsenic （As） contamination in the food chain. Pot experiments were conducted at the Wheat Research Centre, Dinajpur, Bangladesh to examine the role of water management （WM）, As and phosphorus （P） on yield and yield attributes of boro （variety BRRI dhan 29） and aman （variety BRRI dhan 32） rice. A total of 18 treatment combinations of the three levels of As （0, 20 and 40 mg/kg） and P （0, 12.5 and 25.0 mg/kg） and two WM strategies （aerobic and anaerobic） were investigated. Yield attributes were significantly affected by increasing As levels. Grain yields of BRRI dhan 29 and BRRI dhan 32 were reduced from 63.0 to 7.7 and 35.0 to 16.5 g/pot with increasing As application, respectively, indicating a greater sensitivity of BRRI dhan 29 than BRRI dhan 32. Moreover, As toxicity was reduced with aerobic compared to anaerobic WM for all P levels. During early growth stages, phytotoxic symptoms appeared on BRRI dhan 29 and BRRI dhan 32 rice stems with increasing As levels without applying P under anaerobic WM. Under anaerobic and As-contaminated conditions, BRRI dhan 29 was highly susceptible to straighthead, which dramatically reduced grain yields. There were significant relationships between the number of effective tillers per pot and root dry weight, grain yield, and number of fertile and unfertile grains per pot for both BRRI dhan 29 and BRRI dhan 32 （P＆lt;0.001）. Our findings indicate that rice could be grown aerobically in As-contaminated areas with a reduced risk of As toxicity and yield loss.     

Selenium Alleviates Carbohydrate Metabolism and Nutrient Composition in Arsenic Stressed Rice Plants

This study reported the influence of selenium (Se) on carbohydrate composition and some related enzymes and nutrient compositions of arsenic (As) stressed rice plants. Rice plants of cultivar PR126 were grown on soil amended with As in a range of 25–100 μmol/kg with and without 0.5 or 1.0 mg/kg Se. Total soluble sugars (TSS) and reducing sugars (RS) increased in leaves of As stressed plants at the tillering and grain filling stages whereas sucrose and starch contents showed the reverse trend. Se supplementation to As stressed plants further increased TSS and RS, and enhanced sucrose phosphate synthase activity in rice leaves, thus improving sucrose content and the tolerance to As stress of the plants. Se alone or in combination with As resulted in lower As accumulation in rice husk and grains, and the highest reduction was observed in Se applied at 1.0 mg/kg compared to the corresponding As treatments alone. As may limit the accumulations of Na, Mg, K, Ca, Fe, Zn and Mn in rice grains, which are essential for humans. Binary application of different combinations of As and Se protected the plants against As and increased the mineral content in rice grains. Addition of Se in As treated soil significantly alleviated As stress by enhancing grain yields compared to the corresponding As treatment. It is concluded that Se induced amelioration of the toxic impact of As in rice either by modulating carbohydrate composition and/or nutrient uptake is one of the mechanisms to alleviate As stress in plants.     

Effect of Milling and Parboiling Processes on Arsenic Species Distribution in Rice Grains

This study identified the role of milling and parboiling on arsenic (As) content and its species in large numbers of rice samples. Total As contents were 108 ± 33 μg/kg in polished rice grains (PR), 159 ± 46 μg/kg in unpolished rice grains (UR), 145 ± 42 μg/kg in parboiled polished rice grains (PPR) and 145 ± 44 μg/kg in parboiled unpolished rice grains (PUR). The percentages of inorganic As (iAs) were 66% ± 8% in PR and from 72% to 77% in other grain categories. The polishing process reduced the As content in the rice grains, removing outer part of the UR with high amount of As, whereas the parboiling technique transferred the semimetal content within the grain. Total As and iAs contents were not significantly different in UR, PPR and PUR, homogenizing its distribution inside the grains. The results allowed to understand how different operations affect As fate and its chemical forms in grains.     

Arsenic Stress Responses and Tolerance in Rice: Physiological,Cellular and Molecular Approaches

Arsenic (As), a potentially toxic metalloid released in the soil environment as a result of natural as well as anthropogenic processes, is subsequently taken up by crop plants. In rice grains, As has been reported in Asia, North America and Europe, suggesting a future threat to food security and crop production. As³⁺ by dint of its availability, mobility and phytotoxicity, is the most harmful species of As for the rice crop. Specific transporters mediate the transport of different species of As from roots to the aboveground parts of the plant body. Accumulation of As leads to toxic reactions in plants, affecting its growth and productivity. Increase in As uptake leads to oxidative stress and production of antioxidants to counteract this stress. Cultivars tolerant to As stress are efficient in antioxidant metabolism compared to sensitive ones. Iron and selenium are found to have ameliorating effect on the oxidative stress caused by As. Microbes, even many indigenous ones, in the plant rhizosphere are also capable of utilizing As in their metabolism, both independently and in association. Some of these microbes impart tolerance to As-stress in plants grown in As contaminated sites.     

Arsenic Accumulation in Rice: Sources,Human Health Impact and Probable Mitigation Approaches

The human body loading with arsenic (As) through rice consumption is a global health concern. There is a crucial need to limit As build-up in rice, either by remediating As accumulation in soils or reducing As levels in irrigation water. Several conventional approaches have been utilized to alleviate the As accumulation in rice. However, except for some irrigation practices, those approaches success and the adoption rate are not remarkable. This review presents human health risks posed due to consumption of As contaminated rice, evaluates different biomarkers for tracing As loading in the human body, and discusses the latest advancement in As reducing technologies emphasizing the application of seed priming, nanotechnology, and biochar application for limiting As loading in rice grains. We also evaluate different irrigation techniques to reduce As accumulation in rice. Altering water management regimes significantly reduces grain As accumulation. Bio- and nano-priming of rice seeds improve germination and minimize As translocation in rice tissues by protecting cell membrane, building pool around seed coat, methylation and volatilization, or quenching harmful effects of reactive oxygen species. Nanoparticle application in the form of nano-adsorbents or nano-fertilizers facilitates nano-remediation of As through the formation of Fe plaque or sorption or oxidation process. Incorporating biochar in the rice fields significantly reduces As through immobilization, physical adsorption, or surface complexation. In conclusion, As content in cooked rice depends on irrigation source and raw rice As level.     

Genomic Prediction of Arsenic Tolerance and Grain Yield in Rice: Contribution of Trait-Specific Markers and Multi-Environment Models

Many rice-growing areas are affected by high concentrations of arsenic(As). Rice varieties that prevent As uptake and/or accumulation can mitigate As threats to human health. Genomic selection is known to facilitate rapid selection of superior genotypes for complex traits. We explored the predictive ability(PA) of genomic prediction with single-environment models, accounting or not for trait-specific markers, multi-environment models, and multi-trait and multi-environment models, using the genotypic(1600 K SNPs) and phenotypic(grain As content, grain yield and days to flowering) data of the Bengal and Assam Aus Panel. Under the base-line single-environment model, PA of up to 0.707 and 0.654 was obtained for grain yield and grain As content, respectively; the three prediction methods(Bayesian Lasso, genomic best linear unbiased prediction and reproducing kernel Hilbert spaces) were considered to perform similarly, and marker selection based on linkage disequilibrium allowed to reduce the number of SNP to 17 K, without negative effect on PA of genomic predictions. Single-environment models giving distinct weight to trait-specific markers in the genomic relationship matrix outperformed the base-line models up to 32%. Multi-environment models, accounting for genotype × environment interactions, and multi-trait and multi-environment models outperformed the base-line models by up to 47% and 61%, respectively. Among the multi-trait and multi-environment models, the Bayesian multi-output regressor stacking function obtained the highest predictive ability(0.831 for grain As) with much higher efficiency for computing time. These findings pave the way for breeding for As-tolerance in the progenies of biparental crosses involving members of the Bengal and Assam Aus Panel. Genomic prediction can also be applied to breeding for other complex traits under multiple environments.     

转基因水稻外源蛋白检测技术研究进展

 随着转基因水稻研究及其向产业化的发展,检测转基因水稻中存在的外源蛋白成为该领域的研究热点。阐述了目前检测转基因水稻外源蛋白(EPTR)采用的技术手段,并列举了一些可能用于EPTR检测的潜在蛋白检测技术,初步分析了EPTR检测技术需要解决的问题,并预测了EPTR检测技术的发展趋势。     

砷胁迫下磷用量对不同磷效率水稻苗生长、磷和砷吸收的影响

 通过盆栽试验研究了苗期砷胁迫下磷用量对磷高效水稻99011和磷低效水稻99056生长以及对P、As吸收的影响。试验设3个磷水平（0、30、150 mg/kg）和5个砷水平（0、25、50、100、200 mg/kg）。结果表明,苗期施砷显著增加了两个水稻品种地上部及地下部砷的含量,降低了两个水稻品种的株高、分蘖数、地上部及地下部干质量;施磷不但促进了两个水稻品种的生长,而且还增加了根系对砷的吸收量。当土壤砷浓度为25 mg/kg和50 mg/kg时,施用30 mg/kg磷抑制了两个水稻品种砷向地上部的转移,但施用150 mg/kg磷却促进了砷向地上部的转移。相同的处理,磷高效水稻99011地上部干质量和根干质量均显著高于磷低效水稻99056。施砷后,在30 mg/kg磷水平上磷低效水稻99056的砷转移系数最低。     

稻米品质形成和调控机理概述

针对国内外稻米品质的研究现状,分析了稻米品质的形成机制,探讨了不同生育期稻米品质形成的影响因素。在全球气候变化的背景之下,如何适应CO2浓度和温度增高的影响将是今后提高稻米品质的研究方向之一。     

Review and Prospects on Rice Breeding and Extension in China

Rice is the most important food crop in China. In 2004, the planting area was about 2.8973×107 ha accounting for 28.5% of the total planting area of food crops, and the yield reached 1.7769×107 t accounting for 37.8% of the total food output. Breeding a…