"Rock-Ad" a New Cultivar of Wild Rocket
|Analysis of a new line of rucola named Rock-Ad has promise to become popular|
|Dalia Maurer, et al.|
|September 14, 2014|
Wild rocket (Diplotaxis tenuifolia) from the Brassicaceae family is a Mediterranean plant with the common name - Rucola. In Italy, rucola is widely consumed where its pungent qualities are appreciated, both in a salad and as a garnish. Rucola is a fast growing, cool-season crop and flowers under long days and high temperature. This crop is well adapted to the Israeli climate which offers the possibility of growing it all year round, in the open field and with season extension techniques as it is adapted to greenhouse culture. The main obstacles to this crop appear to be early flowering during spring and autumn and limited storability. Flower stems are not desirable at harvest time, because they continue to grow during storage and reduce the adjacent leaf quality.
Since rucola is edible and genetically modified organisms (GMO) are forbidden in Europe this method could not be usable to try to modify flowering time of the plants. An alternative method, used in this study to address the problem, was by mutagenesis of the commercial cultivar, and selection of mutant lines carrying the desired traits. Here we present the analysis of a new line of rucola named Rock-Ad, created by Ethyl Methane Sulphanate (EMS) mutagenesis. This cultivar has a delay in flowering time and improved postharvest storability compared to the commercial cultivar (Kenigsbuch et al. 2009) as seen in fig.1.
The crop quality
The quality requirements of the market for rucola are for leaves to be dark green, rough and lobed shaped. Flawless shaped leaves are known as Rocket /Eruca. Counting lobed shape leaves at the stage of bolting of rucla, grown under greenhouse conditions, gave the average of 13.5±0.9 leaves per plant of Rock-Ad, compared to 9.2±1.3 leaves per plant of the commercial type. Similar results were obtained when the rucola was grown in the field. These experiments showed that the percentage of leaves suitable for marketing from the Rock-Ad cultivar was 75% compared to 65% in the commercial cultivar.
This work was supported, in part, by the grant No. 430/0065 from the Herbs Growers Organization in Israel. Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, No.619/11
Thanks to Dr. Susan Lurie for critical review.
Martinez-Sanchez, A., Marin, A., Llorach, R., Ferreres, F. and Gil, M.I. 2006. Controlled atmosphere preserves quality and phytonutrients in wild rocket (Diplotaxis tenuifolia). Postharvest Biol. Technol. 40:26-33.
Kenigsbuch, D., Ovadia A, Ivanova, Y., Chalupowicz, D., Maurer, D., Aharon, Z., Vinokur, Y. and Aharoni, N. (2009) Wild Rocket (Diplotaxis tenuifolia) Mutant with Late Flowering and Delay in Postharvest Senescence. Acta Horticulturae. 830:91-96.
Fig. 1: Rucola in a net-house, both types sowed and planted at the same time: behind, the commercial
Fig. 2: percent of flowering plants per days.
Fig. 3: bunches of the two types after storage: the commercial rucola (left) is much yellower than the Rock-Ad (right).
Table1. Leaf yellowing after harvest. Freshly cut wild type rucola leaves from the commercial cultivar and mutant Rock-Ad were placed in modified atmosphere or in ventilated atmosphere for seven days at 20oC.
Dalia Maurer, Daniel Chalupowicz, Alona Ovadia, Shahar-Ivanov Yelena and David Kenigsbuch*.
Dept. of postharvest science of fresh produce, ARO, The Volcani Center, Bet-Dagan, Israel.