Introduction. Optimising agricultural water use implies the combination of physiological, technological and engineering techniques, especially those for continuously monitoring the water status of plants subjected to deficit irrigation. A methodology to estimate water stress of young almond trees from thermal images was developed based on assessing the physiological status of almond crops under limited water-supply conditions. Materials and methods. Two irrigation treatments were tested during the maximum evapotranspirative demand period (214th to the 243rd day of the year) in an experimental almond [Prunus dulcis (Mill) D.A. Webb, cv. Guara] orchard: a low-frequency deficit irrigation (LFDI) treatment, irrigated according to the plant-water status, and a fully irrigated treatment (C100) at 100% of crop evapotranspiration. Daily canopy temperature at midday (TC) was measured with an infrared camera, together with standard measurements of stem-water potential (ΨStem) and stomatal conductance (gS). The time course of these parameters and their relationships were analysed. Results and discussion. The time course of the parameters studied showed highly significant correlations among the differentials of canopy-air temperature (ΔT), ΨStem and gS. The methodological protocol for analysing thermal images allowed a time saving in processing information and additionally offered the possibility of estimating the ΨStem and gS values. Conclusion. Our results confirm that infrared thermography is a suitable technique for assessing the crop-water status and can be used as an important step towards automated plant-water stress management in almond orchards.

Introduction. Sweet cherry fruit is a very perishable commodity, because fruits decay and lose water rapidly after harvest as a consequence of their high respiratory rate. The objective of the present study was to evaluate the effect of the combination of hot water plus essential oil treatments and hot water treatment alone on the quality of ‘0900 Ziraat’ sweet cherries during cold storage. Materials and methods. Fruits were divided into four groups and were treated by dipping into water at 24 °C for 30 s (control), dipping into water at 60 °C for 30 s, and dipping into water at 60 °C for 30 s plus either menthol treatment or thymol treatment. After treatments, all fruits were packed in polypropylene bags and stored at 0–1 °C temperature and 90–95% relative humidity for 45 days. Physical and chemical changes were determined at 15-day intervals during storage. Results and discussion. All of the postharvest treatments improved fruit quality characteristics compared with fruit of the control. According to the data, after 45 day s of storage, combination treatments were found to be more effective in controlling decay. The treated fruits had higher total anthocyanin and total phenolic compounds. In control fruits, total anthocyanin and total phenolic compounds initially showed a slight increase, but their accumulation significantly decreased with time.

Introduction. Chinese jujube originated in China and has become a leading fruit tree in the northern part of China with total production of 4,250,000 t in 2009 and total planting area of 1,500,000 ha. Among the reported 944 Chinese jujube cultivars or strains, ‘Zanhuangdazao’ is the unique natural triploid cultivar; it is characterized by big fruit, high yield and good adaptability compared with the other diploid cultivars. Therefore, our group began polyploid breeding through colchicine induction starting in 2000. Cultivar origin. ‘Chenguang’ is a new Chinese jujube cultivar induced by colchicine on the stem apex of the diploid ‘Linyilizao’. Through three years of top-grafting and purification, its characteristics were observed in grafted and top-grafted experimental orchards continually. In 2009, ‘Chenguang’ was released by the Hebei Forestry Cultivar Examination and Approval Committee and became the unique tetraploid Chinese jujube cultivar in the world to date. Cultivar characteristics. The somatic chromosome number, botanical character, phenological phase, productivity and adaptability are given. ‘Chenguang’ is suitable for growing in Shanxi, Hebei, Shandong Province, where the annual average temperature is 12–14 °C and rainfall is above 400 mm, or similar soil and climate conditions. Main cultural techniques. Propagation, the training system, fruit setting and disease control are explained and recommended.