Horticultural performance of ‘Marinada’ and ‘Vairo’ almond cultivars grown on a genetically diverse set of rootstocks

Abstract

Evolution of almond planted area and production has been mainly due to the arrival of new cultivars and rootstocks that have contributed to improve agronomic characters such as yield, precocity and efficiency. In recent years, are becoming available new cultivars that have contributed to provide late blooming time and self-fertility, and with ease to adapt for mechanical harvest and high-density. However, there is scarcity of studies where the interaction of these new cultivars with hybrid rootstocks has been tested. The aim of this study was to assess the performance of Cadaman ® , Garnem ® , INRA GF-677, IRTA-1, IRTA-2, Ishtara ® , Adesoto, Rootpac ® 20, Rootpac ® 40, and Rootpac ® R rootstocks with two promising almond cultivars such as 'Marinada' and 'Vairo'. Bloom and nut ripening dates were affected by rootstock genotype. Both 'Marinada' and 'Vairo' cultivars showed low biennial bearing, with some differences among rootstocks, with IRTA-2 and Adesoto inducing the lowest values. On the other hand, Adesoto had higher number of suckers than the rest of the rootstocks. Garnem ® provided the biggest trees, followed by Cadaman ® , and then a third group which comprised IRTA-2 and INRA GF-677. Rootpac ® 20 was the most dwarfing rootstock, followed by IRTA-1, Adesoto, Ishtara ® , Rootpac ® R, and Rootpac ® 40. In terms of yield efficiency and partitioning index, IRTA-1, INRA GF-677, and Rootpac ® R were the ones with higher values. Differences in tree volume and vigor for these rootstocks suggested that INRA GF-677 would be a suitable rootstock for low-medium planting densities with wide spacings; whereas Rootpac ® R and IRTA-1 would be suitable rootstocks for medium-and high-density 2 plantings. Findings of this study showed dramatic differences in tree vigor, yield, kernel weight, yield efficiency, and partitioning index, which provide a wide range of options to deem for each cultivar in a particular climate and management.

Remote Sensing Energy Balance Model for the Assessment of Crop Evapotranspiration and Water Status in an Almond Rootstock Collection

“…Garnem R , Cadaman R , and INRA GF-677 provided the highest values for the same structural traits. These results are in agreement with, for instance, those reported by Lordan et al (2019), who evaluated tree canopy vigor in the same rootstock trial for a longer period and also identified Garnem R , Cadaman R and INRA GF-677 as those with the greatest tree volume, and Rootpac R 20 as the most dwarfing rootstock in the trial. In agreement, Yahmed et al (2016) also observed that Garnem R and Rootpac R 40 were, respectively the most and medium vigorous rootstocks and that scions grafted on Rootpac R 20 were the most dwarfing.…”

“…The effect of rootstock on tree canopy vigor has been widely reported through in situ measurements of TSCA, canopy volume or LAI ( Russo et al, 2007 ; Gullo et al, 2014 ; Mestre et al, 2015 ; Yahmed et al, 2016 ; Lordan et al, 2019 ). However, this study demonstrates the feasibility of using very high-resolution multispectral airborne imagery to estimate the architectural traits of the vegetation in an almond rootstock trial and to use them to estimate ET a .…”

“…For many years, breeding programs for fruit crop rootstocks, as well as for obtaining scion cultivars, have used similar evaluation methods based on both agronomic and molecular traits. Some of the commonly measured agronomic traits are trunk cross-sectional area (TCSA), plant height, tree canopy vigor, phenology, yield parameters, and fruit quality attributes ( Reighard et al, 2011 ; Font i Forcada et al, 2012 ; Legua et al, 2012 ; Lordan et al, 2019 ). However, most of these agronomic traits are a consequence of differences in the root system architecture or the hydraulic properties of a rootstock, which contribute in influencing the transpiration rate through their effects on the stem water potential (Ψ s t e m ) and the control of stomatal conductance ( Hernandez-Santana et al, 2016 ).…”

Comparison of SHD and Open-Center Training Systems in Almond Tree Orchards cv. ‘Soleta’

“…With respect to the TCSA, the values for the open-center trees were very similar to those reported by Alonso Segura et al [25] (326.3 cm 2 ), but the reported yield efficiency, a widely used parameter for other fruit tree species (although not for almond trees), was much higher than those obtained in this study (49.9 g/cm 2 ). The lower TCSA values for the Rootpac-20 rootstock would be in agreement with Ben Yahmed et al [39] and Lordan et al [56], who studied the dwarfing effect through the significant slow growth of the trunk, finding that this rootstock would have 35−45% less vigor than GF677.…”

“…This could be explained by the effect of rootstock. Lordan et al [56] reported larger fruit size of 'Marinada' and 'Vairo' cultivars on GF-677 when compared with Rootpac-20 (both trained in open-center).…”