Characterization and field performance of two strawberry cultivars under Moroccan conditions

This work aims to study some agronomic parameters on strawberry cultivars installed at the experimental field of Larache, National Institute of Agricultural Research of Tangier, Morocco. The study was carried out on two cultivars of strawberry Fortuna and Victory. The results showed that the Victory cultivar (11.85Kg / plant) had a better yield compared to the cultivar Fortuna (5.26Kg / plant). The sugar level between the different stages increased to 2.7c/o for Victory and 2.62c/o for Fortuna in the red stage 3⁄4 and then decreased to 2.5 for both varieties. The Victory cultivar showed greater leaf area and higher average stomatal conductance compared to the Fortuna cultivar, while the Fortuna cultivar showed higher chlorophyll content compared to the Victory cultivar. Keyword— Strawberry, Fortuna cv, Victory cv, Moroccan condition.

INTRODUCTION Strawberries (Fragaria x ananassa Duch.) are widely grown fruit crop in the world, adapted in geographically diverse area [1]. Strawberry varieties which widely consumed and desired by the people community is a sweet, brightly colored, and large of strawberry variety. The methods for determination of strawberry phylogenetic relationships is based on morphological and anatomical characters [2]. Variations in the strawberry plant are among the advantages of the plant, making it possible to create plant hybrids affected by the close phylogenetic relationships of several phenotypic appearances [3]. In Morocco, The strawberry sector has experienced continuous development in the northern zone of Morocco, mainly at the Loukkos perimeter. This development has been favored by the proximity of Europe, the availability of land, water and labor. The areas cultivated as well as the production have evolved significantly from 750ha with 31.00 T harvested in 1995 to 3500 ha on average in recent years with a production of 140 000 T before falling to 3050 ha (including 50 ha in organic) [4]. On the socioeconomic level, Morocco annually exports about 19 thousand tons of fresh strawberries and 47 thousand tons of frozen strawberries. On average, the turnover made by strawberry and other red fruits is of the order of 1.5 billion DH, of which nearly 90% is exported. The activity also generates 3 million working days over a period of 9 months, from September to May. The strawberry represents a great economic and agro-industrial interest; however its production faces some difficulties at the origin of the loss of its quality and its yield. For this Morocco have several physiological and morphological researches on red fruits. Indeed, as part of the national medium-term program for the genetic improvement of strawberry we conducted an agronomic study on two strawberry cultivars installed at the delta 9 greenhouse of the Larache experimental field, National Institute of Agricultural Research of Tangier, Morocco.

II.
MATERIAL AND METHODS Two cultivars of Fortuna strawberry of American and Victory origin of Spanish origin (Table 1) were installed at the Larache experimental station to evaluate their varietal behavior. These two cultivars are installed in delta 9 greenhouses, and were planted with 4 complete random block layouts. The Fortuna plantation took place on 01/10/207 and Victory on 20/10/2017. Flowering instead on the 10/11/2017 for Fortuna and the 25/11/2017 for Victory. Each elementary parcel is made up of a ridge 60 meters long and 7 meters wide with four rows spaced 60 cm apart. The space between two ridges is 70 cm. We studied some physiological parameters such as chlorophyll level [5] and stomatal conductance [6], so we assessed the sugar content and taste quality of both cultivars.

Leaf area:
We compared the leaf area of the two cultivars Victory and Fortuna, the results shown in Figure 3 show that there is a remarkable difference between the leaf area of Fortuna and Victory. The Victory cultivar shows a leaf area greater than 0.097 cm 2 compared to the Fortuna cultivar with a leaf area of 0.084 cm 2 .

The chlorophyll content:
The average chlorophyll level was measured for the plants of both varieties using a chlorophyll meter (SPAD). Fig. 4 shows the variation in the chlorophyll content of the two cultivars Fortuna and Victory, noting that the chlorophyll content of the Fortuna cultivar is higher compared to the Victory cultivar.

Stomatal conductance:
We studied stomatal conductance, to determine the effect of water stress on stomatal opening. Fig. 5 shows the mean stomatal conductance in both cultivars; mean stomatal conductance in Victory cultivar is very high than stomatal conductance in Fortuna cultivar.