高油玉米花粉直感等遗传效应对普通玉米产量及品质的影响

通过大田试验筛选出了高油玉米为普通玉米单交种授粉来达到增产和提高普通玉米含油量、蛋白质含量的组合。所筛选出的 3个组合 (SN3×HO115、SN3×HO2 98、SN98_1×HO2 98)中 ,与普通玉米自身相比较 ,子粒产量分别提高 145 7 6、146 5 1和 136 3 1kg/hm2 ,油产量分别提高 2 96 1、32 3 3和 30 0 8kg/hm2 ,蛋白质产量分别提高 2 96 0、15 6和 389 6kg/hm2 。高油玉米的花粉直感及与普通玉米杂交的杂交优势效应在大田玉米生产中应用前景广阔。

Heterosis Analysis of Nitrogen Use Efficiency for Grain Production of Brassica napus L.

[Objective]The aim was to study heterosis of N use efficiency for grain production （NUEg） of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N content of six B.napus parents （Zheshuang 3,Yangyou 7,ZJ1,Shilijia,Ningyou 14 and Huyou 16） and their F1 combinations from 6 × 6 complete diallel cross in maturity stage under two N levels were measured; heterosis of NUEg,combining ability and heritability size were analyzed and calculated. [Result]The results showed that NUEg has obvious heterosis; combining ability variance analysis indicated that NUEg was mainly controlled by additive,dominant and cytoplasmic effects; genetic variance analysis showed that additive effects and dominance effects were all significant in low nitrogen fertilizer and dominance effects were significant in high nitrogen fertilizer. [Conclusion]NUEg of B.napus has obvious heterosis.

Genetic Effects and Heterosis in Plant Height and Internode Traits of Japonica-Indica Hybrid Rice

[Objective] This study aimed to investigate the genetic effects and heterosis of plant height and internode traits of japonica-indica hybrid rice. [Methed] Incomplete diallel crosses were made between six japonica CMS lines and nine indica widecompatibility restorer lines; the genetic effects of plant height and internode traits of japonica-indica hybrid rice were analyzed using the additive-dominance genetic model. [Result] The ple, nt height, panicle length and the length of internode 1 of japonica-in- dica hybrid rice were mainly controlled by the additive effects; but the length of in- ternode 3, internode 4 and internode 5 were mainly controlled by dominance effects. Both the narrow sense heritability and broad sense heritability of plant height, panicle length, number of elongated internodes and length of most internodes reached signifi- cance level. The positive phenotypic correlation, genetic correlation, additive correla- tion and dominance correlation between plant height and panicle length, number of e- longated internodes and internode length were significant; and most of the other paired traits were significantly positively correlated. Heterosis analysis showed that the positive heterosis value over mid-parent and positive heterosis value over better- parent of the length of internode 3, internode 4, internode 5 and internode 6 reached significant level, and the heterosis value over mid-parent of plant height reached extreme significance level. [Conclusion] This study will provide reliable theoretical basis for the genetic improvement and heterosis utilization of plant height and internode traits in japonica-indica hybrid rice.

Estimate of Genetic Parameters of Grain Yield and Some Agronomic Traits in Durum Wheat Using Diallel Crosses

Five varieties of durum wheat were crossed in full diallel fashion through 2010/2011 growing season. The five parents and their 20 F1 progenies were grown in 2011/2012 at the farm of faculty of agricultural and forestry, Duhok university, Iraq, using randomize complete block design with three replications to estimate heterosis, heritability and some genetic parameters for yield and its components. The results showed highly significant difference among genotypes for all studied traits. The parent Um Raby-5 had a positive general combining ability effect for most traits including grain yield. The crosses （Kokorete71× LD - 357E）, （Crezo × Um Rahy-5）, （Cimeto×Um Raby-5）, （Cimeto×crezo） and （Cimeto × Kokorete 71） exhibited significant desirable specific combining ability effect for most traits. The dominance was greater than additive almost traits. Heritability inbroad sense was high but heritability in narrow sense was low. The expected genetic advance as percent of traits mean was low for all traits. Most crosses showed significant positive heterosis for most traits and two crosses, （Crezo Cimeto） and （Cimeto Urn Raby-5） had the highest positive heterosis for the most studied traits including grain yield.

Yield trait improvement of bay scallops following complete diallel crosses between different scallop stocks

This study describes the complete diaUel hybridization between newly introduced bay scallop stock （W） from Canada and local commercial stock （D） grown under laboratory conditions, in China. Larval survival and growth during all life stages （larvae, spat, and adult） were compared among hybrid （DW, WD） and purebred （DD, WW） populations. Significant heterosis was detected for survival during the larval stage （〉 1% of the mid-parent values）. The mean heterosis （Hm） varied in growth throughout the life span. More than 50% of the Hm values were positive and negative in the DW and WD groups, respectively. The influence of maternal effects and mating types （intrapopulation vs. interpopulation crosses） on growth for all life stages was not consistent. Larval survival did not differ significantly （P〉0.05） with maternal effect or mating type. In the harvest stage, shell length （SL）, shell height （SH）, shell width （SW）, and total weight （TW） were larger in the hybrid compared with the inbred groups. Positive Hm values were observed in SL （1.5%）, SW （5.8%）, and TW （12.3%）, and were more significant in the DW groups （6.1%, 4.5%, 6.8%, and 27.2%）. These results suggest that hybridization between two geographic populations is a good tool for improving bay scallop growth. However, unstable heterosis between the two populations requires further study.

Innovative Technology to Produce Safe and High Quality African Catfish, C/arias gariepinus, Products from Aquaculture in Egypt

The present study was designed to test the intra-specific crossing of two Egyptian populations from African catfish （Clarias gariepinus）, EI-Manzalah catfish （MCF） characterized by tolerates for poor water quality and easily farmed in captivity and EI-Qanater catfish （QCF） characterized by rapid growth and high quality flesh, for hybrid vigor, production and food processing to create new high quality products. Crosses of these populations were carried out in EI-Gamalia hatchery, EI-Manzalah, Egypt, during spring of 2008 between MCF~~ QCF~. African catfish hybrid, MCF and QCF fingerlings with a mean weight of 24.02 ＋ 1.38 g were stocked at a density of 50-fish per m3 in cages （112 m3 each） suspended in lake El-Manzalah. Fish were fed a formulated diet containing 31.20% crude protein and cultured for 214 days. The growth, survival and production data confirmed that catfish hybrid has been successful and showed a strong heterotic effect. Hybrid catfish had a significantly highest production, 47.5 kg per m3 and best feed conversion ratio （1.33） which demonstrates that cages are a viable alternative to ponds for the commercial production of African catfish and its hybrids. Recently, the African catfish market has required more processed products. The results indicated that： （1） there are slightly variations in African catfish population＇s products quality; and （2） the hot-smoked and fried-coated fish fillets products are more safe foods and acceptable to consumers due to their physic-chemical properties and microbial load acceptable results.

Heterosis and Inbreeding Depression in Sunflower

Information on heterosis and inbreeding depression for yield and agronomic characters is essential for sunflower （Helianthus annuus L.） breeding programs. This research was conducted to evaluate heterosis and inbreeding depression for yield and agronomic characters of hybrids involving eight sunflower inbred lines. These inbred lines were crossed in 8×8 half diallel to obtain 28 F The 28 hybrids were self-pollinated to produce the F2 generation. The 8 parents, 28 F1 hybrids and 28 F2 populations hybrids were evaluated using a randomized complete block design with three replications at two locations in Nakhon Ratchasima （SUT Farm and National Corn and Sorghum Research Center） in 2009. Mid-parent heterosis and inbreeding depression were estimated for yield, head diamete oil content, 1,000-seed weight and plant height. Significant differences were found among the parents, F1 hybrids and F2 populations for all traits. F1 hybrid means were significantly higher than the parental means for all traits. In addition, F1 hybrids considerable heterosis and heterobeltiosis when compared with the mid-parent and better parents, respectively. Yield, showed oil content and plant height showed highly positive heterosis in F1 hybrids, ranging from 14.48 to 49.45%, 8.88 to 33.22% and 9.51 to 29 respectively. Similarly, heterobeltiosis were positive significant for yield （19.22 to 49.04%）, oil content （8.65 to 28.30%） and height （2,83 to 27.61%）. However, 1,000-seed weight showed a low level of heterosis in F1 hybrids （-9.36 to 8,07%） oil content, 1,000-seed weight and plant height in F2 populations were lower than their respective Fi hybrids the F2 populations was comparatively high for yield, oil content and plant height. The cross of lines 5A×for yield （49.45%） and 1,000 seed-weight （8.07%） but low 25%, plant Means for yield, Inbreeding depression in 2A gave the highest heterosis inbreeding depression for yield （10.06%）. Based on the mean performance and heterotic effects for seed yield, 1,000-seed weight and oil content, the inbred lines 2A and 5A are suggested for the development o hybrids,