基于智能算法优化SVM的横向通风过程中温度场预测方法探究

将改进的智能预测技术应用于储粮横向通风过程中的粮堆温度预测,为粮食通风智能预测与决策提供了一种新思路。选取河北清苑国家粮食储备库冬季横向通风的实时监测数据,在分析主要影响因素的基础上,应用三种智能优化算法——网格寻优算法、GA遗传算法寻优、PSO粒子群算法,结合回归支持向量机理论,对粮堆的通风过程进行建模。结果表明,优化过的回归预测模型能较好地拟合粮食温度与其他变量之间的非线性关系,尤其是当样本数量较为有限时,该方法具有更高的拟合精度,更适合对储粮通风这一强非线性过程的预测研究,对于人工干预操作具有一定的现实指导意义。     

如何提高奥氏气体分析仪检测粮堆中CO_2和O_2浓度的准确度

介绍了检测粮堆中CO_2和O_2气体浓度所用奥氏气体分析仪的构造、原理、操作,提出了提高奥氏气体分析仪检测准确度的方法建议。     

缓释环流熏蒸防治磷化氢抗性害虫应用研究

通过应用缓释环流熏蒸的方法,可使磷化氢维持浓度100 mL/m3以上,保持33 d,彻底将磷化氢抗性较高的赤拟谷盗害虫全部杀死,起到较好的防治作用,为抗性害虫的防治工作提出了有效的治理方法。     

30℃条件下不同氮气浓度对储粮害虫控制效果研究

在30℃±1℃,70%±5%R.H.的条件下,研究90%、95%和98%浓度的氮气对储粮害虫的控制效果,结果表明:90%以上的氮气浓度均可以控制各试虫成虫产生下一代;95%和98%的氮气均可用于储粮害虫的防治,但95%氮气控制害虫需要气调的时间较长,需要根据实际防治时的经济阈值进行选择;98%氮气对各虫种均有较好的控制效果。氮气气调可用于对PH3抗性害虫的防治。     

鄱阳湖生态经济区粮食产量的影响因素分析

鄱阳湖生态经济区是中国南方粮食生产的重要区域,为推进鄱阳湖生态经济区战略,保障粮食生产,加快发展现代农业,利用鄱阳湖生态经济区域内25个县市的粮食产量的相关数据进行相关分析、主成分分析和通径分析,探讨影响鄱阳湖生态经济区粮食产量的主要影响因素。研究结果表明,粮食作物播种面积的影响最大,其次是有效灌溉面积和化肥使用量（折纯量）。鄱阳湖生态经济区的粮食生产在农业科技投入上仍需加强,同时要处理好粮食生产与保护生态环境之间的关系,大力发展可持续的新型生态农业。     

耕作和培肥对豫中区冬小麦生长和产量性状的影响

以‘百农矮抗58’为试验材料,在2007-2008年度深耕土壤的基础上,于2008-2009年度研究了深耕（耕深40 cm）和浅耕（耕深20 cm）2种耕作方式和底施专用复合肥（B1）、专用复合肥+鸡粪（B2）及专用复合肥+饼肥（B3）3种培肥模式对豫中区冬小麦生长和产量性状的影响。结果表明：浅耕模式下小麦的株高、群体数量、叶片叶绿素含量及地上部单株干物质积累量均高于深耕模式。B3培肥模式下,小麦叶片的叶绿素含量和植株地上部分干物质积累量较高。浅耕+B3模式下成穗数和穗粒数极显著高于其它模式,产量较高。综上,深耕基础上,浅耕配施复合肥和饼肥是豫中区适宜的种植模式。     

Nitrogen Accumulation and Translocation for Winter Wheat under Different Irrigation Regimes

The translocation of pre‐anthesis nitrogen to the grain is an important source for winter wheat. The relation between the nitrogen translocation and irrigation regime was studied in the field under a rain‐proof trough shelter. Nitrogen (N) translocation amount, N translocation efficiency decreased with a decline in irrigation amount or by excessive irrigation. Compared with different organs, the leaf and stem had higher N translocation amounts, and contributions to grain for both cultivars – Jinan 17 and Lumai 21, indicating that stem also is a major N source for grain development. The contribution of pre‐anthesis total above ground N to grain N ranged from 57 to 76 %, indicating the importance of pre‐anthesis storage of N for achieving high grain N concentrations. Grain nitrogen and yield (kg ha^?1) were positively and significantly correlated with the N translocation amounts and contributions, respectively, suggesting that the sink strength may be involved in the translocation of N from a vegetative organ to the grain. N harvest index (NHI) was significantly correlated with N translocation efficiency, suggesting that the latter is a prerequisite for increasing grain N and improving grain quality. The experiment showed that N translocation status is enhanced by better irrigation practices, but limited by severely deficient or excessive irrigation.     

The use of grain protein deviation for identifying wheat cultivars with high grain protein concentration and yield

The relationship between grain protein concentration and grain yield in different cultivars of winter wheat was examined in a series of field experiments carried out over three years, in which 13, 12 and 8 cultivars were studied in each year, respectively. The plants were grown at sites located in Shropshire, west-central England, in years 1 and 2, and at three other locations in eastern England in year 3. Above ground plant samples were collected at an thesis and again at maturity, when they were separated into grain and straw, and analysed for dry matter and N content. Analysis of residuals from regression of grain protein concentration on grain yield (grain protein deviation, GPD) showed that some cultivars had a higher grain protein concentration than was predicted from grain yield alone. It was deduced that the capacity to accumulate a higher grain protein concentration than predicted from grain yield is under genetic control and thus may be improved through breeding. Other factors (weight of N accumulated in the biomass at anthesis, weight of N accumulated in the biomass between anthesis and maturity and the concentration of N remaining in the straw at maturity) were added step-wise into the regression to enable statistical analysis of their relative contributions to grain protein. High GPD may be achieved through increased N accumulation after anthesis, combined with efficient re-translocation of vegetative N reserves. The use of GPD provides a selection criteria in wheat breeding programs to screen for increased grain protein concentration without a concurrent grain yield reduction. This revised version was published online in August 2006 with corrections to the Cover Date.     

A rapid, seedling-based bioassay for identifying low cadmium-accumulating individuals of Durum wheat (Triticum turgidum L.).

We have developed a seedling-based bioassay that iscapable of identifying low Cd-accumulating phenotypes(homozygous and heterozygous) after 96–120 h ofexposure. Our experiments were conducted using¹⁰⁹Cd as a tracer at subtoxic concentrations tosimulate conditions that might be experienced in thefield. Supply of Cd (10^-11 M) to 4-d oldseedlings for 0–8 h resulted in no differences in rootand leaf Cd content between the low (TL05) and high(TL04) Cd-accumulating isolines. Increasing time ofexposure produced significant differences in leaf Cdaccumulation between isolines, with differencesbecoming most pronounced after the bulk of appliedcadmium ( 95%) was depleted from absorption solutions( 72 h). Similar results were obtained with8-d old seedlings, where differences between genotypeswere more pronounced in young leaves (2nd leaf) orshoot bases. Individuals from five low and highCd-accumulating near isogenic pairs (50individuals/isoline) were screened using Cdconcentration of shoot bases as the screeningcriterion. Mean scores within each isoline pair weresignificantly different, although overlap ofindividual scores was observed at intermediate foliarCd concentrations. The 2^nd leaf to root Cdcontent ratio, which reflects root to shoottranslocation, provided a better parameter todistinguish low from high Cd-accumulating isolines. Plants used for this bioassay could also be rescuedfor subsequent experimental crosses, providing a rapidand cost-effective tool for early detection of the lowCd-accumulating phenotype.     

Effect of Storage Conditions on Germination in Wheat

The percentage germination was determined for storage of wheat at four grain moisture contents (15, 18, 21 and 24 %), four temperature levels (4, 15, 25 and 40°C) and three levels of mechanical damage (0, 15 and 30 %). The effect of each level of moisture was investigated using three replicates for each temperature and each level of mechanical damage. During storage, at 0.25, 0.5 and 1 % dry matter loss (DML), germination tests were carried out on samples taken from each of the above treatments. The percentage germination was compared statistically amongst treatments. The analysis showed significant differences among most of the treatments. The percentage germination decreased very slowly at a low moisture level (15 %), low temperature (4°C) and low level of damage (0 %), while it decreased rapidly at a high moisture level (24 %), high temperature (40°C) and high level of damage (30 %). For example, the percentage germination was 41 % when the wheat was stored at 4°C, 15 % mechanical damage and 24 % moisture content after a storage time of 36.5 days, while the percentage germination was 88.3 % when the wheat was stored at 4°C, 15 % mechanical damage and 15 % moisture content after a storage time of 104 days.