印度稻米生产与标准研究

印度稻米等级标准源于1937年颁布的农产品分级和商标法。印度的大米标准分成常规稻米标准和巴斯马蒂米标准两大类。常规稻米分等标准相对简单,主要以含碎米率为分级指标,适用于国内贸易。巴斯马蒂米等级标准比较完善,以粒长、长宽比、不完善粒以及膨胀率等指标分等,专门用于出口贸易。总体来说,印度稻米标准起点不高,对碾磨程度、缺陷粒的要求较松,国际贸易中一般采用国际食品法典Codex的农残标准。     

湖南优质稻品种品质指标间的相关性分析

对湖南省评选出的221个优质稻品种(组合)的主要米质指标进行了分析,探析了品质性状与评定等级的关系。结果表明,在一定范围内,稻米垩白粒率和垩白度越大,等级越低;而粒型长宽比和胶稠度越大,等级越高。湖南省二、三等优质品种的出糙率要求高于国家相应标准,垩白度和胶稠度要求低于国家相应标准。30年来,湖南省评选的优质稻品种米质有较大改善,但垩白粒率、垩白度仍普遍偏高。相关回归分析表明,稻米垩白粒率与垩白度呈极显著正相关,垩白粒率、垩白度与出糙率、精米率呈显著正相关,与粒型长宽比、整精米率、胶稠度、碱消值和食味值呈极显著负相关;粒型长宽比、整精米率与胶稠度、碱消值和食味值呈极显著正相关。     

玉米子粒大小及其衡量方法

玉米子粒大小及其整齐度是玉米商品品质的重要指标之一。目前,常使用粒重(百粒重)来衡量子粒的大小,但粒重不能真实反映粒的体积和大小。通过对吉林省133个玉米品种子粒大小的研究对比分析,用体积表示法比百粒重法能更好的体现玉米品种子粒大小,提出了玉米子粒大小的体积表示法(粒数/L)和分级标准。分级标准划为3个等级,小粒在2000粒/L以上,中粒在1700～2000粒/L,大粒在1700粒/L以下。参试玉米品种中子粒大小以中粒品种最多,为60.9%,其次是小粒品种,大粒品种最少。     

福建省农科院新育成2个大穗型优质籼型不育系

20 0 2年 7月 10日 ,福建省农业厅受福建省科技厅委托 ,组织 8名权威专家对福建省农科院稻麦研究所育成的籼型不育系京福 1Ａ、京福 2Ａ进行了技术鉴定。ａ)稻米品质。据农业部稻米及制品质量监督检验测试中心检测 ,京福 1Ａ(Ｂ)和京福 2Ａ(Ｂ)品质优良。京福 1Ａ(Ｂ)糙米率、精米率、碱消值和蛋白质含量 4项指标达优质食用稻米一级标准 ,粒长、长宽比和胶稠度 3项达二级标准。京福 2Ａ(Ｂ)糙米率、精米率、整精米率、粒长、碱消值、蛋白质含量 6项指标达优质食用稻米一级标准 ,垩白度、透明度和胶稠度 3项指标达二级标准。其中 ,整精米率和…     

我国稻米加工工艺的沿革与展望

我国稻米加工起步于大规模采集野生稻的时期,最初是采用稻谷直接制成米的“稻出白”工艺,后来采用稻谷先制成糙米、糙米再制成米的“糙出白”工艺,两者构成了沿用几千年的古代稻米加工工艺;19世纪60年代开始,增加稻谷清理、白米整理等工段,构成了近代稻米加工工艺;到20世纪末,增加稻谷分级、下脚整理、稻壳整理、副产品整理、糙米精选、白米精选、白米色选、白米抛光等工序,构成现代稻米加工工艺;进入21世纪以来,新增了回砻谷净化、糙米净化、刷米与抛光组合、多道色选、留胚粒分选等工序,构成了当代稻米加工工艺;今后通过增加多等级大米联产、多等级大米与留胚米联产等专利加工工艺,将构成加工过程更加精准且智能化、低破碎、低能耗和环境友好的未来稻米加工工艺。     

国际标准稻米规范（续前）

国际标准稻米规范（续前）ＩＮＴＥＲＮＡＴＩＯＮＡＬＳＴＡＮＤＡＲＤ——Ｒｉｃｅ—Ｓｐｅｃｉｆｉｃａｔｉｏｎ附录Ａ（规范）杂质、破碎粒、不完善粒和其它类型稻米的测定。Ａ．１原理杂质、破碎粒，不完善粒和其它类型稻米按糙米、精米、蒸谷糙米和蒸谷精米的类型手...     

稻草还田对水稻生长及稻米品质的影响

以常规品种黄华占为材料,在常规施肥基础上进行稻草还田与稻草不还田的比较试验,结果表明,稻草还田可提高水稻每穗总粒数、结实率、千粒重和糙米率、精米率、整精米率,同时降低垩白粒率和垩白度,提高籽粒长宽比,降低直链淀粉含量,增大胶稠度,使稻米品质得到改善。     

上海软米品种品质性状分析与评价

以上海近年推广种植的8个软米品种为试验材料,对稻米品质进行了相关性分析和主成分分析。结果表明,8个软米品种均未达到部颁优质稻米标准,主要是因为透明度、胶稠度、直链淀粉含量3项指标未达到部颁优质米标准。各性状相关性分析复杂,整精米率与粒长呈极显著负相关,糙米率和碱消值呈显著负相关,胶稠度与蛋白质含量成显著负相关。主成分分析发现,前3个主成分累计贡献率达82.795%,整精米率、糙米率、垩白度、胶稠度、碱消值为最有代表性的品质指标。     

辽宁滨海稻区稻米品质性状与产量及其相互关系分析

以89个辽宁滨海稻区主栽品种及表现优良的后代品系为试验材料,探究稻米品质性状和产量之间的关系。通过对各项指标间进行相关性分析、逐步回归分析发现稻米各品质性状间关系密切复杂,彼此间均存在显著或极显著的相关性,其中稻米长宽比和整精米率与食味值关系密切,在选育高食味值的稻米品种时,可以选择长粒形品种。通过对稻米理化品质与其他品质性状和食味值的分析发现,要提高稻米的外观品质和食味值,应降低稻米的直链淀粉和蛋白质含量。通过对稻米产量与各品质性状间关系的分析发现,长粒形稻米的食味值高,但不易高产。提高稻米品质和食味值与提高产量之间不存在直接矛盾,产量与食味值的回归曲线方程表明产量较高或较低时,与食味值存在不同的趋势,说明单一地追求高产量时会导致食味降低,但在一定产量范围内提高品质,培育兼顾高产量和高品质的稻米是可行的。     

优质食用稻米品质的理化指标与食味的相关性研究

 对全国各地选送的78个优质米样品进行了食用稻米品质的理化指标与食味的相关性研究。其中理化指标包括：粒长、长宽比、垩白率、垩白度、透明度、糊化温度、胶稠度、直链淀粉、蛋白质等9项指标。结果表明：（1）籼稻的粒长因子、垩白因子对食味有极显著正线性效应，粒形因子对食味有极显著负线性效应，对食味的重要性顺序为：粒长因子>粒形因子>垩白因子；（2）粳稻的透明度（级）与食味呈显著负相关系。并对农业部部颁“NY122-86”优质食用稻米标准中，籼、粳稻的直链淀粉含量、胶稠度、糊化温度的Ⅰ、Ⅱ级米的划分标准作了讨论。     

应用无性系变异技术培育黑珍米的研究

紫黑米的营养价值和药用功能早已被人们所认识,近年来,特种米的育种相继展开。1987年,我们从国际著名优质米Basmati 370体细胞无性系变异后代中发现了黑米突变体,经5代连续选育于1990年育成“黑珍米”,本文将其特征及成分与亲本作了初步比较。1 材料和方法以籼稻Basmati 370的成熟胚为起始材料,将脱壳的种子在75%酒精中浸泡1min,放入0.1%升汞溶液中灭菌20min后,用无菌水冲洗3～5次,再放入三角瓶中,每个三角瓶放100粒种子,振荡培养1～2d,当种胚萌动露白时接种在含2,4-D 2 mg/L和6-BA 2mg/L的N6固体诱导培养基上暗培养,当萌动幼胚     

水稻品种Basmati 370和Koshihikari 抗性淀粉颗粒RS2的研究

 以一个优质籼稻品种 Basmati 370 和一个优质粳稻品种 Koshihikari （越光）为材料,研究了抗性淀粉颗粒RS2的来源和链长分布情况。结果表明,两个品种RS2的主要来源均为直链淀粉,体积排阻色谱SEC的分析结果表明这部分直链淀粉不仅包括真正的直链淀粉,还包括了带分支的直链淀粉和带长分支链的支链淀粉。对抗性淀粉颗粒RS2的支链链长分析表明,2个品种长链(聚合度＞36)所占的比例均大于26%。     

不同香稻品种苗期耐高温的形态生理响应

【目的】本研究旨在分析不同香稻品种苗期耐高温的形态生理响应特征,筛选出耐热性较好的香稻品种。【方法】在盆栽条件下,于光照培养箱内,以超级常规香稻玉香油占为对照,研究了常规香稻品种巴斯马蒂、桂香占、农香18、湘晚籼13、象牙香占、中香1号、美香占2号在苗期高温处理下的形态生理响应特征。于高温处理前后测定了8个香稻品种苗期各项形态生理指标。【结果】与玉香油占相比,高温胁迫下,巴斯马蒂的株高、单株鲜质量、单株干质量增幅更大,成活率和过氧化物酶活性更高,丙二醛含量反而下降了33.39%,表明巴斯马蒂的耐高温胁迫能力较好。湘晚籼13在高温处理下的单株干质量增幅与玉香油占相近,株成活率较玉香油占低,胞间二氧化碳浓度变幅较小,SOD活性和丙二醛含量的变幅在8个品种中均为最低,说明其耐高温胁迫的能力略低于玉香油占。农香18、象牙香占和美香占2号的成活率分别为13.33%、12.67%和16.00%。桂香占(4.33%)、中香1号(1.33%)在高温处理后的成活率最低,表明两者的耐高温能力均较差。【结论】8个品种耐热性从强到弱依次为巴斯马蒂、玉香油占、湘晚籼13、农香18、象牙香占、美香占2号、桂香占和中香1号。     

Characterization of Aroma and Agronomic Traits in Afghan Native Rice Cultivars

Abstract

In this study, we collected native aromatic rice cultivars from north, east and northeast of Afghanistan, and check cultivars from Japan, Thailand and India. We characterized some important agronomic characters such as plant height, panicle number per plant, grain number per panicle, 1,000-grain weight, grain length and grain width to find the desirable characters for breeding programs. Many of them were classified into tall culm rice according to IRRI index, but had thin and slender grain, and strong aroma which are favorable characteristics in Afghanistan and surrounding regions. The aromatic character was characterized by three methods, 1.7% KOH sensory test, gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM), and polymerase chain reaction (PCR) analysis. These three methods gave similar results. Six out of 10 Afghan native rice cultivars were aromatic and four non-aromatic. Among the check cultivars, Basmati 370, Jasmine 85, Izayoi, Oitakoutou and Jakouine were aromatic and Nipponbare non-aromatic. Improvement of aromatic and high yielding rice and reduction of plant height are the important objectives for rice breeding in Afghanistan. The results showed that Pashadi Konar from Afghanistan has the intermediate plant height, heavier 1,000-grain weight (32 g), longer grain (11 mm) and favorable aroma. Therefore, this cultivar may be a good source of aromatic rice germplasm in Afghanistan. To clarify the genetic nature of aroma in rice, we crossed non-aromatic cultivar Nipponbare with aromatic cultivar Jasmine 85, and examined the aromatic character in the F₂ generation by 1.7% KOH sensory test and PCR analysis. Non-aromatic and aromatic characters were segregated at a ratio of 3:1, showing that aroma is controlled by a single recessive gene.     

Indica rice varietal development in Pakistan: an overview

Pakistan is well known for its basmati rice with long grain and aroma, as well as for non-basmati indica varieties; however average yield is lower as compared with other countries. Besides, cultural practices, the main reason for low productivity in Pakistan is that, local varieties are susceptible to different biotic and abiotic factors like insect pests, diseases, drought, and salinity. Different approaches have been undertaken in Pakistan to tackle these problems through traditional breeding of selection and crossing, mutation breeding, somaclonal variation as well as plant transformation studies in recent past. For variety development, the most successful examples arose from traditional breeding that produced famous basmati varieties like Basmati 370, Basmati 385 and Super basmati, and non-basmati varieties such as IRRI-6, DR-82, DR-83, DR-92, Swat-I and Swat-II, which earn a significant share of foreign exchange every year. Six varieties have also been developed through mutation breeding, and one through exploitation of somaclonal variation but their contribution to the national economy is not significant. On the other hand, no variety has been registered as commercial by plant transformation groups. This review discusses the problems and prospects of rice breeding with special emphasis on basmati rice in Pakistan particularly in Pakistani Punjab (a major producing area), as well as focuses on future research programs.     

Selenium Accumulation and Antioxidant Status of Rice Plants Grown on Seleniferous Soil from Northwestern India

Greenhouse experiment was conducted to investigate selenium accumulation and its antioxidant response in two rice varieties(PR116 and Pusa Basmati 1121) grown on normal and seleniferous soils. The plant growth was reduced at early developmental stages and flowering was delayed by a period of 10 d on seleniferous soil. Selenium accumulation increased by 3–20 and 13–14 folds in leaves, 18 and 3 folds in grains from Pusa Basmati 1121 and PR116 varieties, respectively. Selenium accumulation in leaves from rice plants grown on seleniferous soil resulted in significant increase in chlorophyll content, hydrogen peroxide, proline, free amino acids, total phenol and tannin contents. Lipid peroxidation levels and peroxidase activities in leaves increased whereas catalase activity showed a reverse trend. It is concluded that selenium accumulation decreased dry matter content in rice during crop development but these plants were able to combat selenium toxicity by inducing alterations in their defense system.     

花香A系列杂交水稻组合产量及米质性状相关及通径分析

对10个花香A杂交组合参加水稻区域试验的产量和品质数据进行相关分析和通径分析。结果表明,产量性状中日产量与有效穗数、株高与穗长、总粒数与实粒数均成极显著正相关,日产量对产量的贡献最大(0.7205),其次为有效穗数;米质性状中整精米率与垩白粒率、长宽比与垩白粒率、垩白度呈显著负相关。提出了以花香A为亲本在配制杂交组合时,应主要通过提高其日产量、有效穗数,并适当延长其生育期、降低其株高与穗长来提升产量;同时,适度降低籽粒长宽比,从而提高灌浆效率,降低垩白粒率、垩白度,进而提高整精米率,提升稻米品质。     

Marker assisted backcross breeding to improve cooking quality traits in Myanmar rice cultivar Manawthukha

Several components contribute to rice grain quality, and among these, fragrance and taste qualities are the most important to consumers. Manawthukha, an elite non-fragrant cultivar with high amylose content (AC), intermediate gel consistency (GC) and gelatinisation temperature (GT), occupies the largest number of acres in Myanmar. To improve fragrance and intermediate AC in Manawthukha, Basmati370 was used as a donor parent to introgress the Basmati alleles of genes conferring fragrance and intermediate AC into Manawthukha by Marker Assisted Backcrossing (MAB). Four backcrosses and one selfing were conducted to transfer positive alleles of badh2 and Wx from Basmati into Manawthukha. Twelve BC₄F₂ selected lines that carried the homozygous Basmati alleles were planted in multi-location trials (four in Myanmar and one in Thailand) and examined for their agronomic performance and cooking quality. The seeds of the improved lines and their parents, harvested from Kamphaeng Saen, Kuaukse, Kyauktada and Latpatan, were investigated for fragrance and AC. All improved lines had fragrance and intermediate AC similar to the donor parent Basmati, whereas their agronomic performances were the same as the original Manawthukha. All improved lines had medium plant heights, high tiller numbers, dense panicles, non-lodging phenotypes and high yielding potentials. Simultaneous improvement of fragrance and intermediate AC indicated that badh2 and Wx genes had major effects on the fragrance and AC, respectively. We show here the success of improving fragrance and intermediate AC by MAB and the high efficiency of selection in early generations. In the present study, MAB accelerated the development of superior qualities in the genetic background of Manawthukha. The improved Manawthukha should be immediately useful for Myanmar farmers and will help farmers to increase their incomes.