15个化杀杂交小麦亲本配合力和杂种优势群的初步研究

为给小麦杂种优势利用提供依据,以15份普通小麦为材料,采用NCⅡ设计组配44个组合,研究了8个农艺性状的杂种优势和配合力。结果表明,杂种F₁的杂种优势是普遍存在的,各性状大都表现出正向优势;周麦22、西农889、西农375和罗大穗316的产量性状一般配合力相对效应较高,参与组配的强优势组合较多。在44个杂交组合中,（D177×罗大穗316）、（周麦22×花培878）、（周98165×西农375）、（周麦22×西农889）、（周麦22×200(1)穗2）、（周麦22×郑育麦9987）、（周麦22×07常261）、（周98165×西农889）、（周麦22×罗大穗316）、（周麦22×西农375）为强优势组合。利用普通小麦亲本8个性状的一般配合力将15份亲本划分为5类,直接以普通小麦亲本8个性状的表现值亦可将15份普通小麦划分为5类。     

黄淮南部和黄淮北部麦区小麦品种间的杂种优势、配合力及遗传特性分析

为了探讨黄淮南部和黄淮北部麦区小麦品种间的杂种优势以及主要农艺性状的遗传特性,以黄淮南部麦区的8个小麦品种和黄淮北部麦区的7个小麦品种为亲本配制56个不完全双列杂交组合,对亲本及杂交组合的9个农艺性状进行杂种优势、配合力及遗传特性分析。结果表明：（1）株高、千粒重和结实小穗数的平均中亲优势较高,单株粒数和穗粒数的平均中亲优势为负向优势,各性状均出现了中亲优势较高的组合,说明黄淮麦区不同生态区小麦品种间具有较强的杂种优势。（2）临Y8012、周麦27和邯生923单株粒重的一般配合力效应最高,其他农艺性状的一般配合力也基本上表现优秀,用作亲本可进一步提高组合的产量。单株粒重特殊配合力较高的组合为百农207×临Y8012、秋乐2122×邯生923、周麦27×济麦39、浚2016×冀麦181、周麦17×冀麦181。组合百农207×临Y8012、周麦27×邯生923和周麦27×济麦39两个亲本的一般配合力效应及特殊配合力效应均比较高,为本研究中的最优组合。（3）株高和千粒重的广义遗传力和狭义遗传力都较高,说明这两个性状加性效应较大且受环境影响较小,直接对这两个性状进行选择可取得良好的效果;单株粒重的广义遗传力较高,但其狭义遗传力较低,非加性方差成分占优势,因而对单株粒重直接选择效果不太显著,需要通过其他相关性状来辅助选择。     

不同粒重小麦品种主要农艺性状的配合力和遗传力分析

为了解小麦粒重对产量影响的遗传规律,选6个千粒重高的品种SH4300、S5707、衡4568、D08-6、LS6109、华育116和6个千粒重低的品种H083-366、旱优0602-25、泰农8681、临抗6180、泰农2987、DH155两组亲本,按NCⅡ遗传交配设计,配制6×6不完全双列杂交获得36个杂交组合,对亲本及F₁的株高、穗长、分蘖、小穗数、穗粒数、单株产量、千粒重7个性状进行了配合力和遗传力分析。结果表明,D08-6千粒重的一般配合力最高,但其余各性状的一般配合力不高,导致其单株产量的配合力最低,做亲本时仅可提高千粒重;LS6109、华育116、S5707的单株产量配合力较高,但千粒重一般配合力都不是最高,主要是通过增加穗长、分蘖、小穗数、穗粒数增加产量。泰农8681、DH155各个性状的一般配合力均较高,其单株产量的一般配合力最高。故LS6109、华育116、S5707、泰农8681、DH155是较好的亲本材料。特殊配合力分析表明,单株产量特殊配合力最高的组合分别是LS6109/泰农2987、SH4300/泰农2987、D08-6/旱优0602-25;千粒重特殊配合力最高的组合分别是D08-6/临抗6180、LS6109/泰农2987、D08-6/H083-366,组合LS6109/泰农2987还具有较高的分蘖特殊配合力;SH4300/泰农2987千粒重的特殊配合力较高,D08-6/旱优0602-25分蘖和穗粒数的特殊配合力较高;组合LS6109/泰农2987、SH4300/泰农2987、D08-6/旱优0602-25在本试验中具有良好的产量表现,是较好的杂交组合。遗传力分析结果表明,株高、穗长、小穗数具有较高的广义遗传力和狭义遗传力（>65%）,可在早代进行选择;分蘖、穗粒重和千粒重广义遗传力较高,但其狭义遗传力较低（<50%）,适合在高代进行选择。     

几个玉米自交系主要数量性状配合力分析

本文按P₁×P₂不完全双列杂交设计,分析了本所利用的7个玉米自交系及其组配的12个组合的株高、穗位、穗长、穗粗、穗行数、行粒数、千粒重、产量等主要数量性状的配合力和遗传参数,根据配合力效应值筛选出4个优良自交系亲本和4个强优势杂交组合。配合力基因型方差与遗传力估算结果表明,大部分性状的加性方差明显大于显性方差,一般配合力表现出比特殊配合力较为大的遗传分量,为此,在选配组合时应注重选择一般配合力高的自交系作亲本。     

黄淮主推小麦品种主要农艺性状配合力及遗传效应分析

为明确黄淮麦区主要推广小麦品种的主要农艺性状遗传规律,通过不完全双列杂交试验研究了济麦22、周麦22、矮抗58、西农979等8个小麦新品种9个主要农艺性状(株高、有效穗数、单株生物学产量、穗长、有效小穗数、穗粒数、千粒重、单穗重、单株粒重)的遗传力和配合力。结果表明,矮抗58、西农979和郑麦366株高的一般配合力较低,济麦22和矮抗58有效穗数的一般配合力较高,烟农19和郑麦366穗粒数的一般配合力较高,周麦22和济麦22千粒重的一般配合力较高,周麦22和烟农19的单株粒重、单株生物学产量和单穗重的一般配合力较高,新麦26和周麦22主茎穗长的一般配合力较高。周麦22/烟农19、济麦22/西农979、济麦22/郑麦366、矮抗58/烟农19四个组合的9个主要农艺性状的特殊配合力效应值均为正向效应。9个主要农艺性状的狭义遗传力差别较大,变化范围为2.83%~97.39%,其中,株高的狭义遗传力最高,达97.39%,其次为主茎穗长(72.07%)、千粒重(40.64%),这三者在杂交育种时以低世代选择效果较好;株高和单株生物学产量受加性效应(24.4、6.8)和显性效应(6.1、14.67)共同作用,株高以加性效应为主,单株生物学产量以显性效应为主;有效小穗数、千粒重和主茎穗长受加性效应(0.22、3.09、0.27)控制,穗粒数和单株粒重受显性效应(8.88、6.29)控制。     

不同大麦品种（系）产量相关性状的杂交优势及配合力研究

为了解我国不同大麦品种（系）产量相关性状的杂种优势及配合力,以我国不同产区的17份大麦品种（系）及其按NCⅡ设计配制的72个杂交F₁为材料,考察其两年度株高、穗下节间长、穗长、单株穗数、穗粒数、千粒重、单株粒重等产量相关性状的表现,分析各性状的杂交优势与配合力。结果表明,株高正向中亲优势（MPH）与超亲优势（HPH）组合比例最高,两年分别为1.00、1.00与0.97、0.95,其次为穗下节间长、穗长及千粒重;穗粒数与单株穗数的MPH与HPH变幅较大,其次是单株粒重与千粒重。株高的一般配合力（GCA）与特殊配合力（SCA）的效应值和变异最大,其次是穗粒数与千粒重,穗下节间长、穗长、单株穗数及单株粒重相对较小。被测性状F₁表型与GCA及SCA均呈显著或极显著正相关。本研究可为我国不同产区大麦品种间的杂交育种及亲本选配提供参考依据。     

12个玉米自交系主要数量性状配合力分析

按(P₁×P₂)不完全双列杂交设计，分析了12个中晚熟玉米自交系的株高、穗位、穗长、秃尖长、穗粗、穗行数、行粒数、单穗重、单株产量、出籽粒、百粒重11个性状的一般配合力、特殊配合力和配合力的总效应，通过对配合力的分析筛选出5个优良自交系、10个优良组合，并对11个性状的遗传力进行了估算。表明每穗行数、穗粗的遗传力较高，在选育自交系时可在早代选择，而单株产量、每行粒数和单穗重的遗传力低，宜在高世代进行选择。     

影响青贮玉米生物产量关键指标的筛选及其遗传研究

采用NCⅡ设计,以26份不同农艺性状的青贮玉米材料按5×21组配了不完全双列杂交。经通径分析,明确了影响青贮玉米生物产量关键指标为秸秆产量、子粒产量、株高3个指标,建立了青贮玉米生物产量回归方程;估算了关键指标的一般配合力、特殊配合力和相应的遗传参数。结果表明：与关键指标显著相关的因素中,株高的一般配合力方差明显高于特殊配合力方差,基因累加效应占主导地位,其狭义遗传力h²_N最高为43.3%;穗长和千粒重的广义遗传力h²_B均在98%以上,环境因素对它的影响较小。说明青贮玉米株高指标宜在早代选择或加强对亲本自身的选择效果,而生物产量、秸秆产量、子粒产量、千粒重、穗长5个指标宜加强杂种优势的利用。     

黄淮麦区杂交小麦亲本的杂种优势和配合力分析

为了研究黄淮麦区普通小麦品种间的杂种优势和配合力的关系并划分杂种优势群,用GriffingⅡ遗传交配设计对10个黄淮麦区普通小麦品种配制45个杂交组合,对亲本及杂交组合进行8个农艺性状的杂种优势和配合力效应分析,再根据亲本的一般配合力和性状表现划分杂种优势群。结果表明：(1)杂交小麦具有普遍的中亲优势和较强的对照优势, 多数性状的超亲优势不强。单株穗数、主穗粒数表现为负向优势,致使单株产量的对照优势下降,是目前制约杂交小麦产量优势发挥的主要限制因素。(2)周98165、小偃22、西农889、郑麦366和偃展4110的产量一般配合力较高。强优势组合有豫农202×郑麦366、周98165×小偃22、小偃22×豫农202、西农2611×小偃22、烟农19×郑麦366、豫农202×邯6172、小偃22×郑麦366、烟农19×周98165、周98165×邯6172。依据双亲之一GCA或双亲GCA之和较大的要求进行亲本选配,强优势组合出现的几率较高。(3)利用配合力分析法将供试亲本划分为5类,利用性状聚类法将供试亲本划分为4类。这两种方法划分杂种优势群都是可行的。     

引进玉米自交系穗部性状的配合力和遗传力研究

选用6个引进的玉米自交系,按照NCⅡ遗传交配设计配制了9个杂交组合（3×3）,研究了8个穗部性状的配合力和遗传力。结果表明：（1）同一自交系不同性状的一般配合力效应值不同,不同自交系同一性状的一般配合力效应值表现也不相同。穗行数、行粒数、轴粗受母本一般配合力效应均达到极显著水平。穗行、秃尖长、穗粗、轴粗受组合特殊配合力效应也都达到了显著或极显著水平。（2）不同组合同一性状和同一组合不同性状的特殊配合力效应值也不尽相同。一般配合力不能够完全决定组合的特殊配合力,一般配合力都高的双亲配组,得到高特殊配合力组合的概率较大：（3）所研究的8个穗部性状的广义遗传力由大到小顺序是：行粒数、穗行数、千粒重、轴粗、秃尖长、穗长、穗粗、穗粒重。狭义遗传力由大到小的顺序是：穗行数、轴粗、穗粒重、秃尖长、穗长、千粒重、穗粗、行粒数。其中,广义遗传力和狭义遗传力都较高的性状有穗行数和轴粗,均在75％以上,它们可以作为进行早代选择的指标。     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.