TTE160

“EFECTO DEL RIEGO DEFICITARIO CONTROLADO SOBRE LA VARIACIÓN TEMPORAL DEL ÍNDICE DE CLOROFILA EN NOGAL ( Juglans regia L.) Y AVELLANO EUROPEO ( Corylus avellana L.)”

“Effect of controlled deficit irrigation on time-course of chlorophyll index in walnut ( Juglans regia L.) and hazelnut ( Corylus avellana L.)"

Felipe Javier Ignacio Jara Cavalieri (1)

(1) Alumno tesista, Universidad Católica de Temuco. Email: fjara2012@alu.uct.cl

ABSTRACT

Controlled deficit irrigation is an agrotechnical practice that consists in restricting irrigation during a particular development phase or throughout the growing season, causing mild to moderate stress with minimal impact on yields and/or fruit quality. The objective of this research is to evaluate the effect of controlled irrigation deficit on time-course of chlorophyll index in young pot-grown plants of walnut ( Juglans regia L.) cv. Serr and hazelnut ( Corylus avellana L.) cv. Tonda Di Giffoni. The experiment was carried out in the period between October 2019 and March 2020 in the facilities of the San Juan Pablo II Campus, Universidad Católica de Temuco. For the experiment, 18 plants of hazelnut Tonda Di Giffoni and walnut cv. Serr, were used. Half of the plants per species were randomly selected to apply a deficit irrigation treatment which was compared against a well-irrigated control. To determine the irrigation thresholds, the gravimetric method was used. From the results, the treatments were defined and consisted in supply of 50% of usable water (T50, deficit irrigation treatment) and 90% of usable water (T90, well watered treatment). The chlorophyll index as SPAD values, was measured with a chlorophyllometer (Apogee instruments, Logan, USA). The repeated measurements of the chlorophyll index were averaged and analyzed for each species using a t-student applied on each measurement date. Seasonal mean SPAD values by species were calculated and then values subjected to a two-way analysis of variance. In walnut, the average weight of the pots during the evaluation season was 5.32 kg and 4.4 kg for T90 and T50, respectively, which percentage-wise corresponded to a difference of 20%. In hazelnut, these values were 5.17 and 4.39 kg, reaching 18% of difference. Meanwhile, the SPAD values for walnut were 33.17 and 30.14 in the T90 and T50 treatments, respectively, while for European hazelnut they were 35.72 and 35.06 along the season. The results obtained in each evaluated date showed that SPAD values in in walnut were sensitive to deficit irrigation, contrasting with that observed in hazelnut where differences were observed

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