诱变与杂交结合选育超高产小麦品种的效果

为了培育超高产小麦优良品种,提出了用辐射诱变亲本,提高小麦亲本之间的遗传差异,从而增强杂交优势的理论。2003~2004年用X射线连续2年照射处理上一年处理播种出的小麦干种子。2005~2007年用高能X射线"放疗"和核磁共振双重处理,连续重复处理3年,在2007年获得大量多种类型的畸形突变植株。利用这些突变材料作为亲本,与大田中表现好的正常植株进行杂交。在杂交后代中又出现了大量的畸形突变植株,从中选出了大粒和超大粒小麦材料。这可能是突破了大粒性状和高秆性状的基因连锁关系,出现了大粒中秆和大粒低秆材料。这一理论的技术实践和材料的获得,为小麦杂种优势的诱发利用开辟了新的思路和方法,也为选育超级小麦品种创造了丰富的选种和育种材料。     

不同类型水稻品种的籽粒灌浆生理

以汕优６３号（源限型品种）和盐粳２号（库限型品种）为材料；研究了两类型品种籽粒灌浆生理差异。主要结果：以淀粉积累来表示籽粒灌浆过程，源限型品种强、弱势粒淀粉积累是异步的，而库限型品种则是同步的；两类型品种强、弱势粒的淀粉合成酶、淀粉磷酸化酶活性和呼吸速率的变化与淀粉积累速率曲线基本吻合；内源激素ＡＢＡ（Ａｂｓｃｉｓｉｃａｃｉｄ）参与籽粒灌浆过程调节，内源ＡＢＡ水平高，强、弱势粒灌浆速率慢，反之则快。     

水稻籽粒材料力学特性研究

本文从水稻籽粒抗压、抗剪、抗冲击试验仪器及试验方法的研究着手,对我国水稻各品系的籽粒,在不同的工况下进行了大容量的试验测定,并运用统计科学的方法进行数据处理,从而得出早籼稻糯稻、晚籼稻及粳稻三大类籽粒的材料力学特性相关数学模型。确立了该特性参数的敏感区及在不同含水率工况下其特性参数的应选数值和范围。     

Biochemical changes in wheat during storage at three temperatures

Biochemical changes in wheat grains stored at 10, 25 and 45 °C for six months were studied. A significant decrease in pH and an increase in titratable acidity was observed during storage of wheat grains at 25 °C and 45 °C. Moisture contents of wheat grains decreased by 15% at 25 °C and 26% at 45 °C during six months of storage. A significant decrease in water soluble amylose (20–28%) along with an increase in insoluble amylose contents (7.6–17%) were observed during storage at 25 and 45 °C. Amylase activity of the samples showed a decrease as the storage progressed. Total soluble sugars increased by 9% at 10 °C and 12% at 25 °C; a 37% decrease was observed after six months storage at 45 °C. Total available lysine decreased by 18.0% and 22.6% at 25 and 45 °C, respectively, after six months storage. In vitro protein digestibility of wheat grains decreased by 5.00% at 25 °C and 10.28% at 45 °C during six months of storage. However, no significant biochemical changes occurred during storage at 10 °C.     

农户兼业、生产环节外包与农业种植结构“趋粮化”

粮食安全是国家安全的重要基础。随着农户兼业化趋势的加强,农村务农劳动力不断流失,生产外包服务市场不断发展,在这个大背景下,农户兼业和生产环节外包对农业种植结构"趋粮化"的影响引发社会各界关注。本文基于全国9省调查数据,通过构建中介效应检验模型分析三者之间的作用逻辑及因果关系。研究结果表明:农户兼业在总体上促进种植结构"趋粮化",生产环节外包特征变量在农户兼业影响种植结构调整的过程中发挥部分中介效应,此外,被访者性别、年龄、家庭总收入、村庄地形和交通设施对农户粮食种植结构调整也存在显著影响。据此,本文认为,为引导农户种植结构"趋粮化",保障国家粮食安全,要合理引导农村劳动力外流,统筹城乡发展;推动农业生产环节外包市场的发育与完善,提高农业生产过程中的外包服务率;同时,制定合理的价格支持政策,保障农户种粮积极性。     

酒糟和窖泥中苏云金芽孢杆菌的分离及鉴定

从泸州老窖酒厂的酒糟和窖泥中采集的168个样品中分离出苏云金芽孢杆菌1株,经光学显微镜观察伴孢晶体形态为菱形。以cry1/7/9、cry2、cry3、cry5、cry6、cry8、cry4/10、cry11、cry1Ⅰ的引物做PCR分析进行基因型鉴定,发现该分离株有cry1基因。同时还对该株蛋白质图谱和杀虫活性等特性分析,结果表明该分离株对小菜蛾有一定活性,死亡率可达80%,但该菌株对致倦库蚊无活性。     

利用BIL群体定位水稻垩白粒率QTL

以粳稻品种南粳35和籼稻品种N22构建的回交重组自交系(BIL)群体为研究材料,于不同年份对控制水稻垩白粒率的QTL进行定位。结果表明,BIL群体中,垩白粒率在不同年份均为偏向高垩白亲本的连续分布,表现为数量性状特征;利用Win QTLcart 2.5软件共检测到6个控制垩白粒率的QTL,分别位于第2、2、3、6、8和12染色体上,单个QTL对表型的贡献率介于8.96%~12.51%,加性效应值介于8.38%~14.36%,除qPGWC-6增加垩白粒率的基因来自N22外,其余QTL增效基因均来自南粳35。利用QTLNetwork 2.0软件2a共检测到3个QTL,分别位于第5、6和8染色体上,其中qPGWC-6和qPGWC-8与Win QTLcart2.5检测的位点相同,没有检测到上位性QTL对垩白粒率的影响。     

Whole grain phytochemicals and health

Phytochemicals and antioxidants in whole grains have not received as much attention as the phytochemicals in fruits and vegetables although the increased consumption of whole grains and whole grain products has been associated with reduced risk of developing chronic diseases such as cardiovascular disease, type 2 diabetes, some cancers and all-cause mortality. Recent research has shown that the total phytochemical content and antioxidant activity of whole grains have been commonly underestimated in the literature, and that whole grains contain more phytochemicals than was previously reported. Most whole grain phenolics are in bound form, 85% in corn, 76% in wheat, and 75% in oats. In addition, whole grains contain unique phytochemicals that complement those in fruits and vegetables when consumed together. The beneficial effects associated with whole grain consumption are in part due to the existence of the unique phytochemicals of whole grains. The majority of phytochemicals of whole grains that are beneficial for health are present in the bran/germ fraction. In whole wheat flour, the bran/germ fraction contributed 83% of total phenolic content, 79% of total flavonoid content, 78% of total zeaxanthin, 51% of total lutein, and 42% of total β-cryptoxanthin. The bran/germ fraction of whole wheat may therefore impart greater health benefits when consumed as part of a diet, and help reduce the risk of chronic diseases. This paper will review recent research on the phytochemicals and antioxidant activity of whole grains and their unique contribution to the health benefits of whole grains.     

中国主要粮食作物产后损失特征及减损潜力研究

为减少作物产后损失,增加粮食供应数量。该文基于物质流分析方法以及农产品流动特征,建立了一套量化作物产后损失的计算方法,在已有数据基础上,重点分析了2010年中国三大粮食作物(水稻、小麦和玉米)产后(包括收获、运输、干燥和储藏)损失特征及其减损潜力。结果显示,中国作物产后损失率较高,水稻、小麦和玉米产后综合损失率分别为6.9%、7.8%和9.0%,三者平均损失率7.9%,高于发达国家作物产后损失水平。粮食产后损失中,储藏环节损失比重最高,损失比例达到40.3%,其次是收获环节,为31.4%,运输和干燥环节损失较小,分别为11.1%和17.2%。农户储藏和收获是作物产后减损的重点环节。情景分析结果显示,通过改进产后不同环节技术条件,可以有效减少作物产后损失,情景5(粮食产后环节技术条件达到最优)三大粮食作物产后损失率均可以降低到4.0%以下。由此可见,中国粮食作物产后减损存在较大潜力,减损重点应落在农户储粮环节以及作物收获环节。作物产后减损需要国家农业科技政策作保障,通过提升农户科学储粮意识以及提高作物机械收获水平和改进作物收获质量等综合措施,最终实现中国粮食作物产后损失的降低。研究结果为中国粮食产后减损政策和措施的制定及实施提供借鉴。     

杉木地理种源花粉形态的研究

为研究杉木地理种源对杉木花粉的影响,将引种在一起的11个产区的杉木花粉进行系统的观察。观察表明:杉木花粉粒为球形与近球形,大小(32.9—40)×(29.9—35.5)u。杉木花粉有内外壁,外壁表面具粗或细的两种类型瘤状纹饰,以及分布不均匀的星状微颗粒,其中外壁纹饰为粗瘤状,星状微颗粒小而少,外壁纹饰为细瘤状,星状微颗粒大而多。根据杉木花粉粒的大小,形状,外壁纹饰等特征,将其分为二类型。