Genetic studies on some vegetatable crops ( Corchorus olitorius L. and Lactuca sativa L. )

The present study aimed to estimate genetic variability and determine the relationships among eight Jew’s Mallow (Corchorus olitorius L.) accessions and five Lettuce (Lactuca sativa L.) accessions obtaining from National Gene Bank (NGB). This study was carried out 15 morphological traits of Jew’s Mallow and 11 characters for Lettuce, as well as karyotype and ISSR-PCR analyses. Significant differences were recorded for almost criteria of Jew’s Mallow, especially leaf length and leaf width, no. of leaves per plant, weight of harvested leaves and harvested index, except weight of total plant. Accessions 8 and 7 possessed higher values than others for important characteristics, leaf length and leaf width, no. of leaves per plant, weight of harvested leaves and harvested index. Estimate of heritability in broad sense was high (range from 67.56 – 93.55 %). Karyotype analysis confirmed that accession 8 was the highest values, while the accession 7 possessed the lowest values for chromosomal characters. Amplified DNA fragments produced a total 39 bands, ranging from 207 – 1807 bp. A total 36 bands were polymorphic with mean of polymorphism 92.31%. Investigated eight accessions was divided into two groups at distance 0.760. The first group includes accession 1; and the second group further divided into two subgroups. The highest similarity (0.99) was recorded between accessions 4 and 6. High significant differences were recorded for most traits specially position young leaf, position of leaves, size and weight of head. Accession 1 possessed the highest values for important leafy traits. The important leafy traits varied in heritability estimate (25.34 – 95.65%). The accession 5 recorded the highest values for chromosomal traits. Amplified DNA fragments produced a total of 25 bands ranging from 194 – 1247 bp. A total of 22 bands were polymorphic with average percentage of polymorphism was 83.30%. Investigated five accessions were divided into two groups at distance 0.95. The first group included accession 1 only. The second group was further divided into two subgroups at distance 0.99. The highest similarity (1.00) was recorded between accession 3 and accession 5.