Combining Ability of Different Agronomic Traits and Yield Components in Hybrid Barley
Selection of parents based on their combining ability is an effective approach in hybrid breeding. In this study, eight maintainer lines and nine restorer lines were used to obtain 72 crosses for analyzing the general combining ability (GCA) and special combining ability (SCA) for seven agronomic and yield characters including plant height (PH), spike length excluding awns (SL), inter-node length (IL), spikes per plant (SP), thousand kernel weight (TKW), kernel weight per plant (KWP) and dry matter weight per plant (DWP). The results showed that GCA was significantly different among parents and SCA was also significantly different among crosses. The performance of hybrid was significantly correlated with the sum of female and male GCA (TGCA), SCA and heterosis. Hu1154 A, Mian684 A, 86F098 A, 8036 R and 8041 R were excellent parents with greater general combining ability. Five crosses, Hu1154 A×8032 R, Humai10 A×8040 R, Mian684 A×8037 R, Mian684 A×8041 R and 86F098 A×8037 R, showed superior heterosis for most characters.
Estimation Heterosis and Combining Ability for Yield and Yield Contributing Traits in Two -Rowed Barley Using Line X Tester
Original: 31/12/2017 Revised: 04/02/2018 Accepted: 06/02/2018 Published online: Five diverse genotypes of tow-rowed barley were crossed with a line × tester fashion. Combining ability for grain yield and yield related in tow-rowed barley was investigated in a set of two female lines, three male testers and their six F1’s hybrids. Analysis of variance detected highly significant differences for all of the quantitative traits studied among the genotypes, among the parents for GCA, among the crosses for SCA, while most traits among Parents x crosses and among Lines x Testers. The parent GOB (line) had a positive and significant effect for grain yield plant -1 only. Two crosses were found to be well enough specific combiners for grain yield plant -1 with maximum SCA effect in cross GOB x MSEL. The estimated value of σ2A was greater than its σ 2 D for grains spike -1 , thousand grain weight and plant height, which pointed out the predominance of additive gene action as the ratio of σ 2 A/σ 2 D was more than unity, whereas the rest of the traits viz., spike plant -1 , spike length, harvest index biological yield plant -1 and grain yield plant -1 appeared overbalance of non-additive gene action. The average degree of dominance values for spike length and 1000grain weight indicated partial dominance while rest of the traits showed over-dominance. All the crosses, excluding CANELA x MSEL, showed good positive and significant heterosis for grain yield plant -1 .
Comparison between Two Chemicals for Reducing Scale Formation in Reverse Osmosis Systems
In this present research was transacted with the calcium carbonate scale inhibition on the membrane surface of the reverse osmosis desalination system. Influence of changing feed solution flow rate (10-25)l/h, pH of the feed solution (6-10) on the recovery ,penetrate flow rate and total dissolved solid in (RO) system by using solution of calcium carbonate as feed solution was investigated, furthermore the effect of adding two types of scale inhibitor ,zinc chloride and polyamino polyether methylene phosphonate with difference concentration (2-8)mg/l for zinc chloride and (8-15) mg/l for polyamino polyether methylene phosphonate was calculated. The results showed that the permeate rate increases as the feed flow rate augmentation ,while it reducing with time, the total dissolved solids decreases as the feed flow rate increases while it increases with time and recovery rate decreases as the feed flow rate increases and it also decreases with time. It was concluded that the permeate rate decreases as the feed solution pH value increases and it cause high scale forming thus decrease the permeate TDS.By adding the scale inhibitor, it was found that the permeate rate and recovery rates increases as the concentration of inhibitor increases while the total dissolved solids decreases in the permeate with increasing the concentration of both inhibitors .It was discovered that Polyamino polyether methylene phosphonate more sturdy than zinc chloride as scale inhibitor for reverse osmosis desalination system in all concentrations was studied in this article.