BREEDING AND PRODUCING NEW INBRED LINES AND F1 HYBRIDS OF PICKLING CUCUMBERS

Pickling cucumber is considered one of the important types of vegetables in Egypt, but there is less interest in it; this due to the lack of hybrids charactercterized with high productivity and good commercial traits. Production can be increased through increasing genetic diversity and thus productivity via plant breeding. The present experiment was conducted at Kaha Vegetable Research Farm, Wady El- Natroon and Ismailia during 2016-2020. Six cucumber genotypes from Netherland and Sweden Gene Banks (18-CGN, 8-CGN, 16-CGN, 11-NGB, 15-CGN and 21-NGB) were selfed pollinated for 6 generations to have pure inbred lines. They crossed by half diallel method to produce 15 F1 hybrids. Evaluation of the 6 parents, 15 produced hybrids and two commercially hybrids (Livina F1 and Magdalina) was carried out for fruit length, fruit diameter, fruit weight, number of female flowers per node, node of the first female flower, number of fruits/plant and total yield/plant was done. Heterosis, heritability, inbreeding depression and number of genes controlling studied traits were estimated. The results in the cross P1 x P5 showed the highest mid-parent heterosis values for studied characters that were positive by contrast. Most high-parent heterosis values for studied characters were negative. High inbreeding depression was observed. The inbreeding depression was positively and negatively lower significant indicating the presence of vigor in F2. High estimates of narrow and broad sense heritability were observed in the cross P1 x P5, but were moderate for number of female flowers per node and node of the first female flower. Concerning number of effective genes controlling most characters were found to be 1-2 pairs of genes (or group of genes); only fruit weight and node of the first female flower traits controlled by (4) and (9) additive genes respectively.