Broomrapes are holoparasitic weeds responsible for high yield losses in tomato. The efficacy of avail- able means to control them once they have attacked the crop is very limited. Due to this effective and environmental-friendly strategies to prevent these attacks on greenhouse tomato are needed. Both soil solarization and organic supplementation have been proposed to reduce broomrape attacks. However, a setup in their implementation, especially for eradicating broomrape seedbank from highly infested soils, is still needed before they can be widely adopted as a resolutive commercial practice. A set of two experiments was carried out in Southern Italy (37◦03?N, 15◦18?E, 10 m a.s.l.) to study (i) the effect of repeated solarization (for 1–3 consecutive years) and (ii) a single cycle of soil solarization combined with three levels of organic supplementation (0, 0.35 and 0.70 kg m−2), on broomrape seedbank dynamic and fruit yield of greenhouse tomato plants. Soil solarization alone during summer months increased mean maximum soil temperature by about 8.0–13.2 ◦C (at 5 cm depth) and 4.1–9.3 ◦C (at 15 cm depth). After one single cycle of soil solarization alone, seedbank mortality accounted for ∼99% of viable seeds, while induced seeds dormancy accounted for the remaining ∼1%. Complete seedbank eradication was achieved after the second year of solarization, while tomato fruit yield, starting from 3.43 kg plant−1 in unheated soil, peaked after the third year of solarization (6.58 kg FW plant−1). Organic supplementation prior to solarization further increased the temperature of solarized soil at both 5 and 15 cm soil depths (by up to 4.3 ◦C, on average) and enhanced the efficacy of solarization against broomrape seedbank. Indeed, total seeds mortality was induced after a single cycle of solarization combined with 0.35 kg m−2 organic supplement, while tomato yield was enhanced up to 0,70 kg m−2 supplement (9.44 kg FW plant−1). Our results show that in Mediterranean climatic conditions at least two consecutive years of soil solarization are needed to completely eradicate broomrape seedbank from a highly infested soil. However, the effi- cacy of this technique may be improved when combined with organic supplementation, with positive effects on the yield of greenhouse tomato.
|Titolo:||Eradication of Orobanche/Phelipanche spp. seedbank by soil solarization and organic supplementation|
MAURO, ROSARIO (Primo) (Corresponding)
|Data di pubblicazione:||2015|
|Appare nelle tipologie:||1.1 Articolo in rivista|