Root Restriction and Potassium and Calcium Solution Concentrations Affect Dry-matter Production, Cation Uptake, and Blossom-end Rot in Greenhouse Tomato

Abstract

<jats:p>Root restriction has been reported to reduce fruit yield, the incidence of blossom end rot (BER) and K concentration in tomato (<jats:italic>Lycopersicon esculentum</jats:italic> L. `F121') plant organs. The objectives of the present work were to study the effect of root restriction, and combination of K and Ca solution concentrations, on greenhouse tomato fruit yield, quality and cation uptake. Root restriction reduced total yield but improved fruit quality by increasing the dry matter concentration and reducing the incidence of BER. Increasing the K concentration from 5.0 to 10 mmol·L<jats:sup>-1</jats:sup> reduced the marketable yield, due to increased incidence of BER. Root restriction decreased K concentration and K/Ca ratio in tomato plant organs, but had no effect on K uptake rate per unit root fresh weight. Increasing K concentration from 2.5 to 10 mmol·L<jats:sup>-1</jats:sup> increased the K concentration in plant organs and K uptake rate, but reduced that of Ca. In contrast, increasing Ca concentration in the solution had no effect on K concentration in plant organs and K uptake rate. The incidence of BER correlated well with K/Ca concentration ratio in the leaves, whereas a poor correlation was obtained with K/Ca concentration ratio in ripe fruit.</jats:p>

Growing Plants in Soilless Culture: Operational Conclusions

“…In the study of Bar-Tal and Pressman (1996) in the aero-hydroponics system, root restriction decreased Ca uptake rate per plant, but there was a trend of increasing F Ca when root restriction was combined with low K concentration, which is consistent with the ability of the restricted-root plants to maintain Ca concentrations in plant organs similar to those in non-restricted plants. Choi et al (1997) reported that root restriction by small containers (190 ml) strongly suppressed transport of 45 Ca ions to new leaves and apices relative to the plants in the control containers (20 L).…”

“…But even constant supply (as is practical in closed systems) cannot overcome all the constraints posed by small root volume, as discussed in Chap. 9, and by Bar-Tal et al (1990, Bar-Tal and Pressman (1996) and Rieger and Marra (1994). It is therefore important to select the appropriate container size for each specific crop, based on its growth rate and final desired size and growing conditions.…”

“…Another useful approach is the use of liquid culture or aeroponics, where mechanical impedance is practically avoided. However, even in these conditions, increased root density leads, eventually, to growth inhibition (Peterson et al, 1991a;Bar-Tal and Pressman, 1996).…”

Comparative effect of partial root-zone drying and deficit irrigation on incidence of blossom-end rot in tomato under varied calcium rates

“…However, Bar-Tal and Pressman (1996) found that the incidence of BER correlated better with the K:Ca ratio in the leaves than with the K:Ca ratio in the fruits. Nevertheless, a significant antagonistic effect of K on Ca uptake has frequently been observed in hydroponically grown tomatoes; for instance, an increase in K concentration in the nutrient solution often reduces Ca uptake, thus increasing the risk of BER development (Bar-Tal and Pressman, 1996; Wada et al ., 1996; Taylor et al ., 2004). Besides the K:Ca ratio, here we also found that the Mg:Ca ratio in the fruit positively correlated with BER incidence (Fig.…”

Interactive Effect of Nutrient Concentration and Container Volume on Flowering, Fruiting, and Nutrient Uptake of Sweet Pepper

“…Root growth restricted plants produced higher soluble sugars content of strawberry fruits (39), and increased the fruit DW concentration of tomato (40). Root growth restricted plants produced higher soluble sugars content of strawberry fruits (39), and increased the fruit DW concentration of tomato (40).…”