Aegilops cylindrica var.kastorianum (Poaceae): A new variety from Greece

A native population ofAegilops cylindrica was encountered for the first time in Greece in 1980 (near Kastoria, NW. Greece), completely isolated and at a great distance from its main distribution area. There are morphological and chromosomal, but no protein and esterase pattern differences from otherAe. cylindrica populations. This justifies the recognition of a new variety: var.kastorianum. Our comparative and karyotypic observations support the view thatAe. caudata var.polyathera and not var.caudata (typica) is the possible donor of genome C of the new variety.     

Properties of thylakoids and thylakoid particles derived from structurally different chloroplasts

Structurally and functionally different tobacco chloroplasts were subjected to digitonin treatment and subsequent fractional centrifugation. The light-harvesting $\text{chlorophyll}\text{a}\text{chlorophyll}\text{b-}\text{protein}$ complex was found to be enriched in the most dense fraction regardless of the presence of grana in the original preparation. It is suggested that isolated thylakoid membranes and fragments thereof which contain sufficient light-harvesting protein may, under appropriate ionic conditions, form aggregates even when they originate from unstacked thylakoid systems. Comparative studies of fluorescence properties and polypeptide composition of the thylakoids suggest that the light-harvesting protein does not contribute significantly to the fluorescence spectrum of isolated chloroplasts as long as this protein is intimately associated with the Photosystem II (PS II) pigment-protein complex responsible for the 685 nm emission. While the PS II-deficient mutant chloroplasts of the variegated tobacco variety NC 95 lacked both the 685 nm fluorescence component and two or three PS II proteins, one of these proteins was found to be very prominent in our chlorophyll b-deficient mutant thylakoids which also displayed an intense 685 nm fluorescence peak. This correlation supports the contention that a 45 kdalton polypeptide is an apoprotein of pigments associated with the PS II reaction center.     

Effect of gametic disequilibrium on means and on genetic variances of autotetraploid synthetic varieties

Summary The occurrence and effects of a gametic disequilibrium (DSE) in the first generation of a theoretical two-population synthetic variety were investigated. Theoretical development was limited to the genetics at a single locus with two alleles in an autotetraploid species with random chromosome inheritance. Algebraic expressions were developed for the differences between the mean genotypic values of the two-population synthetic variety at generation one and in random mating equilibrium (RME). For the situation where both parents of the synthetic were in RME, a numerical analysis was performed for all possible allele frequencies assuming the following types of genic action: monoplex dominance, partial monoplex dominance, duplex dominance, partial duplex dominance, and additive. The result indicated that with non-additive genic action the DSE could, in some cases, greatly depress or inflate the mean genotypic value of the first generation (Syn-1_(RME)). Thus, any change of means over advancing generations with loss of DSE could be positive or negative. When additive genic action was assumed, there was no effect associated with DSE and when both parents had the same allele frequencies there was no DSE. The DSE, with only a minor exception, decreased the genetic variance and in numerous cases forced it near zero. Expressions were developed for mean genotypic values of a first generation synthetic with DSE in one parent (Syn-1_(DSE/RME)) or both parents (Syn-1_(DSE)). The deviation of these means from those of Syn-1_(RME) was a function of digenic and quadragenic population effects. An inspection of the response equations for Syn-1_(RME) indicated that in a series of crosses with one common parent the rankings of first generation means would be the same as the ranking of populations at equilibrium though the individual means would be biased. More importantly with DSE of one or both parents there are situations when a ranking of first generation mean genotypic values would not reflect relative frequency of desirable alleles in the populations. These results indicate that statistical analyses and selections based on means of the Syn-1 generation can have an error which is not avoidable by improvement in precision of evaluation.Cooperative investigations of the Alfalfa Production Research Unit, United States Department of Agriculture, Agricultural Research Service, and the Nevada Agricultural Experiment Station, Reno, Nevada, USAPaper No. 590 Scientific Journal Series, Nevada Agricultural Experiment Station     

A Simple Construction Procedure for Eesolvable Incomplete Block Designs for any Number of Treatments

A simple, straightforward procedure, which requires no special tables or generators, is presented for constructing resolvable incomplete block designs for v=pk, v=p²k, …, treatments, for k≥p, in incomplete blocks of size k. Also, it is shown, how to obtain incomplete block designs for any v in blocks of size k and k+1. The procedure allows construction of balanced incomplete block designs for p = k a prime number. For p = n not a prime number, incomplete block designs can be obtained by the procedure, but are not balanced. However, for p_s being the smallest prime factor of n, p_s + 1 for v = n², p_s²+ p_s + 1 for v = n³, …, arrangements can be obtained for which the occurrence of any treatment pair in the blocks is either zero or one. This is called a zero-one concurrence design. Procedures are described for obtaining additional zero-one concurrence arrangements. It is shown that the efficiency of these designs is maximum. Both intra-block and inter-block analyses are described.     

Susceptibility of selected apple cultivars to the Mediterranean fruit fly

Ceratitis capitata (Wiedemann), the Mediterranean fruit fly, is one of the key pest species affecting deciduous fruit orchards along the Mediterranean coasts. Because of global warming, C. capitata is gradually spreading north and is becoming a major pest of apples. Determining the susceptibility of the main apple varieties grown in the region will serve as a cornerstone to the management of this pest. In this study, we show the results of a field and laboratory no‐choice test conducted to determine the Medfly preferences on different apple cultivars. The seven main varieties of apples (Gala, Red Delicious, Golden Delicious, Granny Smith, Kanzi, Morgen Dallago and Fuji) were tested. The results demonstrate that C. capitata lays eggs on all apple cultivars in both field and laboratory conditions. The Granny Smith, Red Delicious and Morgen Dallago varieties showed the lowest susceptibility in laboratory conditions, (0.75, 1.55, 2 oviposition punctures/fruit, respectively), with significant differences in oviposition compared to the Golden Delicious, Kanzi and Fuji (3.27, 3.31, 3.1 oviposition punctures/fruit, respectively) varieties, which were shown to be the most susceptible to Medfly attack in laboratory conditions. On the other hand, only slight and not statistically significant differences emerged from the field trials. In relation to the physico‐chemical characteristics, the apple cultivars showing the lowest susceptibility (Granny Smith, Red Delicious and Morgen Dallago) had harder peels and pulps and lower sugar contents than the most susceptible cultivars (Golden Delicious, Fuji and Kanzi). These results were also confirmed through evaluation of larval development on different varieties. In fact, Granny Smith, Red Delicious and Morgen Dallago were the three varieties that did not allow adequate larval and adult development and reduced the possibility of the emergence of a new generation.     

快中子辐照结合组织培养培育花生新品种宇花7号

为开拓新的花生育种方法,对辐照诱变结合组织培养创造花生新种质、培育新品种进行了研究。以我国北方地区主栽花生品种鲁花11号成熟种子为试材,经快中子辐照处理后取种子胚小叶进行组织培养,通过胚胎发生途径获得再生苗。再生苗经嫁接驯化后移栽田间,83个单株获得种子。后代按系谱法进行选育,从83个再生植株后代中获得了107份突变体,分别在主茎高、分枝数、荚果形状和大小、种皮颜色、内种皮颜色、含油率、蛋白含量等性状上发生了明显变异。从突变体后代中选育出了低油早熟耐涝大花生新品种宇花7号,其产量比亲本鲁花11号增产14%以上;其含油率(47.0%)比鲁花11号低5.1个百分点。宇花7号2016年参加辽宁省新品种登记试验,比对照品种白沙1017平均增产13.8%。2018年通过了国家非主要农作物品种登记,登记号为"GPD花生(2018) 370105"。研究结果说明,辐照结合组织培养是创造花生新种质、培育新品种的有效方法。     

不同基质和处理对6种山茶花扦插成活率的影响

研究不同基质和处理对6个拟作为年宵花的山茶花新品种扦插成活率的影响。采用3种不同的基质配比和3种不同的处理对6个品种的山茶花进行了扦插试验。结果表明,泥炭与黄土或珍珠岩的混合基质最适合该6个品种的扦插生根,生根粉对6个山茶花品种的成活率影响不大,但插口加裹黄土后能有效提高其成活率。6个品种在最佳的扦插条件下的成活率在85%-92%之间。研究结果为快速大量地生产这些品种提供技术支持。     

中国水稻地方品种与选育品种遗传多样性的比较分析

利用98对SSR标记对202份中国水稻地方品种和选育品种的遗传多样性进行比较分析.结果显示供试品种具有较丰富的遗传多样性,共检测到等位基因1350个,每个位点的等位基因数(Na)变化范围为3～ 39,平均14个;Nei基因多样性指数变化范围(He)为0.125 ～0.955,平均0.733;多态信息量(PIC)变化范围为0.122 ～0.953,平均0.680;稀有等位基因数(Nr)913个;等位基因丰度(Rs)8.33.栽培稻地方品种和选育品种遗传多样性差异明显,地方品种等位基因数、Nei基因多样性指数、多态信息量、稀有等位基因数和等位基因丰度(Na=1219,He=0.747,PIC=0.710,Nr=756,Rs =8.50)均高于选育品种(Na =919,He =0.704,PIC =0.650,Nr=529,Rs =7.01).各染色体组水平的遗传多样性分析表明,选育品种仅在1号染色体上的遗传多样性高于地方品种,进一步分析显示选育品种的遗传改良在基因组水平上具有区间特异性.