This paper reports an investigation of the effects of process parameters on the quality characteristics of polymeric parts produced by micro injection moulding (μIM) with two different materials. Four injection moulding process parameters (injection velocity, holding pressure, melt temperature and mould temperature) were investigated using Polypropylene (PP) and Acrylonitrile Butadiene Styrene (ABS). Three key characteristics of the mouldings were evaluated with respect to process settings and the material employed: part mass, flow length and flash formation. The experimentation employs a test part with four micro fingers with different aspect ratios (from 21 up to 150) and was carried out according to the Design of Experiments (DOE) statistical technique. The results show that holding pressure and injection velocity are the most influential parameters on part mass with a direct effect for both materials. Both parameters have a similar effect on flow length for both PP and ABS at all aspect ratios and have higher effects as the feature thickness decreased below 300 μm. The study shows that for the investigated materials the injection speed and packing pressure were the most influential parameters for increasing the amount of flash formation, with relative effects consistent for both materials. Higher melt and mould temperatures settings were less influential parameters for increasing the flash amount when moulding with both materials. Of the two investigated materials, PP was the one exhibiting more flash formation as compared with ABS, when corresponding injection moulding parameters settings for both materials were considered.

Two inbred parental lines, their f lt and six inbred lines selected for high yield after three cycles of recurrent selection in this population were evaluated at three locations for two years. The Fj yielded 32.6% more than the midparent value and exceeded the higher parent by 13.3%. The F! also exceeded the midparent values for several components of yield, including lint percentage, weight per boll, number of bolls per plot, lint index, and seed index.The mean yield of the six selected lines exceeded that of the F! by 5.5%. Each of the six lines was higher in lint yield and lint percentage than the higher parent of the original cross, which indicated that transgressive segregation for these traits had occurred.Fifteen possible crosses among the six lines were compared with the above entries at three locations in the second year. These hybrids averaged 9.6% higher in yield than the mean of their parents. Significant heterosis was also detected for lint percentage, weight per boll, number of seed per boll, and lint index.Estimates of general combining ability from the set of diallel crosses were significant for all traits except lint percentage, which demonstrated the importance of additive genetic effects for those traits. The variance for specific combining ability was significant only for lint percentage.

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Seven wheat genotypes were used in this investigation to study the effect of genotypes, levels of polyethylene glycol (PEG) concentrations and their interaction on immature embryo induction, as well as, estimating heritability for in vitro traits. The genotypes were in vitro evaluated for immature embryos culture ability at four levels of PEG concentrations. Significant differences between genotypes were obtained for some traits at four PEG levels. Levels of mean squares were significant for some traits such as number of green point, plant length and number of tillers. Whereas, mean squares of interaction between genotypes × PEG levels was insignificant for all traits except number of tillers. The results demonstrated that the greatest percentages for green points and plant weight were recorded by the hybrid Sakha 93 × Gemmiza 9. In addition, Sakha 93 × Sids 1 was the best genotype for root length and number of tillers. Whereas, the greatest value for number of plantlets was observed in Sakha 93 and sakha 94. The addition of 10 g/l PEG to MS nutrient medium and 1 mg/l NAA and 0.5 mg/l Kinetin in regeneration medium could be the best concentration for immature embryo purpose in wheat. Furthermore, the genetic variations were highly positive for some traits such as number of green point at levels A and B, number of plants at levels A,B and D, plant weight at level A, plant length at level C, root length at level A and number of tillers at levels A,B and D. The values of heritability were ranged between 53.66 to 90.48% for number of tillers at levels D and A, respectively. The results indicated that the genes controlled growing traits in wheat were highly affected by media composition.

The development of local squash hybrids or varieties that have the capacity for higher yielding and earliness over foreign cultivars or hybrids is a pressing need. The objectives of this study were to select the combinations which produce the best F1 by combining different germplasm in crosses. Furthermore, to study heterosis and the nature of gene action associated with this phenomenon. Four varieties belong to Cucurbita pepo L.; Militte (P1), Caserta Italian (P2), Zucchini Grey (P3), Eskandrani (P5) and one variety belongs to C. maxima Duch Abobrinha redonda (P4) were used in this study. In the summer season of 2014, these five varieties were selfed and also crossed to produce 20 F1 hybrids according to the complete diallel crosses mating design. In the spring season, 2015, all the F1 hybrids including their reciprocals and parental varieties were evaluated and grown in a randomized complete blocks design with three replicates. Data were recorded on the following traits: steam length (S.L in cm), the percentage of female flower (FF%), number of days to the first female flower (NDFF), early yield kg/plot (EY/P), number of fruits/plant (NF/P), average fruit weight (FW), total yield/plot (TY/P) and fruit length (FL). The performance of the five parents, the 10 F1 hybrids and their 10 F1r reciprocal hybrids were variable. The P5 appeared to be the best parent for vegetative traits. For yield and fruit traits, once more P5 was not only the best parent but also better than most the F1 hybrids for almost all traits. Heterosis from the better parent was not present for all vegetative traits where, many values were negative. The analysis of complete diallel crosses showed that both GCA, SCA and reciprocal were highly significant indicating their importance. The magnitude of GCA was always larger than SCA. The variances were larger than , although, variances were also present. These results were supported by absence of heterosis from the better parent. The hybrids including P4 as a male or a female parent would be consider as interspecific hybrids. The results indicated that the means of interspecific hybrids i.e. 1x4, 2x4, 3x4 and 4x5 and their reciprocals showed better performance from the other hybrids for many studied traits.

During 2010 and 2011seasons, two field experiments of rice experimental farm of Sakha, Kafr El-Sheïkh, Egypt, were performed through a 6 x 6 diallel system analysis to investigation the combining ability and heterosis and their component features of rice under normal irrigation and drought stress conditions.A broad range of genetic variation among research genotypes was indicated by the routine analysis of variance. As for all the features of normal irrigation and drought stress conditionsThe significance of non-additive genetic variation in the heritage of grain yield / plant has been established by GCA / SCA ratios. While the selection based on the accumulation of the additive effect will boost yield and assign it successfully. According to drought susceptibility index (DSI), four parents and six crosses were the lowest genotypes affected by drought.GCA shows all parental lines are intrinsically performing with a strong index of their overall ability to blend. The combinations of IR7887-176-B-2-B X IR80508-B-194-1-B to boost the output of grain per plant was the best possible cross, as reported by SCA.Under drought, the highest values significant for heterosis from better parent, five crosses for panicle length and seven crosses for number of branches / panicles and grain yield characters. In the general sense, higher heritability levels emerged in normal irrigation; genotypic variances played a major part in phonotypical yield variances and their components.Lower and moderate heritage tests for all yields and their components showed that selection for these characteristics would be successful in late generations.

The rice stem borer (Chilo agamemnon Bles.) is one of the most devastating insects of rice which reducing rice yield in Egypt. The use of resistant rice genotypes remains one of the most reliable methods to control this insect. This investigation aimed to study the mechanisms of resistance (antixenosis, antibiosis and tolerance) in seventeen rice genotypes were evaluated under greenhouse and field conditions. Level of larvae feeding on rice plant was one of the parameter for antixenosis, while weight of larvae or pupae were a measure of antibiosis. Percentage of dead hearts and white heads were used for estimating the tolerance to rice stem borer. The results showed that the hybrid: IR 58025A x Giza 178 R had the highest larval survival percentage, larval weight, pupal weight, dead hearts and white heads. Generally, the hybrid IR 58025A x Giza 178 R and Sakha 101 were the most susceptible and tolerant genotypes, respectively. The tolerant genotypes against stem borer, should have high number of tillers, narrow stem diameter and flag leaf angle. These genotypes could be considered as considers in breeding program to develop new plant type unsuitable for larva stem borer living.