Mitra Razi; Reza Darvishzadeh; Hadi Alipour; Hamed Doulati Baneh
Abstract
Genetic resources in each country are valuable assets for sustainable development. Accurate knowledge of genetic behaviour and identification of genomic loci associated with important economic traits will help breeders to run efficiently their breeding programs. Fourteen important pomological traits ...
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Genetic resources in each country are valuable assets for sustainable development. Accurate knowledge of genetic behaviour and identification of genomic loci associated with important economic traits will help breeders to run efficiently their breeding programs. Fourteen important pomological traits were measured on 45 table grape cultivars during three successive years (2016, 2017 and 2018). The molecular profile of the studied cultivars was prepared with 39 SSR primers pairs. Genetic structure analysis based on the SSR markers revealed two subpopulations in the association panel. In association analysis using the mixed linear model, seven loci were found to be significantly associated with the studied traits at the 5% probability level. Breeding values were also estimated for the pomological traits using BLUP. 'Saghal Solian', 'At Ouzum', 'Garmian', 'Rishbaba Qermez', 'Taifi', 'Shahroudi', 'Sahebi Qermez', 'Lal Qermez', 'Alhaghi', 'Sarghola', 'Chava Ga', 'Qzl Ouzum' and 'Agh Shani' table grape cultivars showed high and positive breeding values for cluster length, width and weight. Whereas 'Garmian', 'Rishbaba Qermez', 'Fakhri', 'Agh Shani', 'Lal Sefid' and 'Shirazi' had positive and high breeding value for pollen germination, fruit set in open pollination and fruit set under controlled pollination. Finally, 'Sarghola' and 'Qzl Ouzum' showed the positive and highest breeding value for berry weight, flesh weight, cluster length, cluster width, and cluster weight. The cultivar with high and positive breeding value can be used as a good parent for the breeding of the traits in hybridization programs because they can better transfer the desirable characteristics to the progeny in each case.
Lavin Babaei; Mohammad Mehdi Sharifani; Reza Darvishzadeh; Naser Abbaspour; Mashhid Henareh
Abstract
To investigate photosynthetic response of some pear (Pyrus spp.) species to drought stress, a pot experiment was conducted using as factorial experiment based on completely randomized design (CRD) with three replication under greenhouse condition. The factors included five pear species including: P. ...
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To investigate photosynthetic response of some pear (Pyrus spp.) species to drought stress, a pot experiment was conducted using as factorial experiment based on completely randomized design (CRD) with three replication under greenhouse condition. The factors included five pear species including: P. biossieriana, P. communis, P. glabra, P. salicifolia and P. syriaca and three levels of drought stress [(100%, 60% and 30% of field capacity (FC)]. According to the obtained results, different levels of drought stress significantly restricted morphological and physiological responses in all studied species. Increasing drought stress intensity reduced leaf relative water content (RWC), net photosynthetic rate, stomatal conductance, transpiration rate and intercellular carbon dioxide concentration when compared to their values in control plants. However, root/shoot dry weight ratio, specific leaf weight and stomatal density per unit of area were increased. In P. glabra exposed to severe stress (30% of FC), the values of root/shoot dry weigh ratio (0.85 g), specific leaf weight (23 mg cm-2), stomata density per unit of area, relative water content (73%) and net photosynthetic rate (3.9 µmol CO2 m-2 s-1) were significantly higher than the other species. P. syriaca, P. salicifolia, P. biossieriana and P. communis were placed in the next ranks, respectively based on their response to drought. In conclusion, P. glabra is reported as a more effective species in mitigating the adverse effects of drought by boosting its protective mechanisms than the other pear species.
